_Note: Amp is SOLD OUT as of December 24, 2023 due to incredible demand. It should be in stock again in a few weeks_ *SHOP for the ZA3 Here* amzn.to/41zmrjT SHOP for Fosi Audio V3 - amzn.to/3PkrK2g 48V 5A Power Supply - amzn.to/3L68Olc Elac Debut 2.0 B6.2 Bookshelf Speakers: amzn.to/3Mmdbcz *RELATED VIDEOS* Fosi Audio V3 Review: ruclips.net/video/U0JwSR0yS_A/видео.html Fosi Audio BT20A-PRO Review - ruclips.net/video/b1zFuLK655g/видео.html More Power in than Out? ruclips.net/video/c7QELbpKMuI/видео.html Mini Amps Video Playlist - is.gd/walminiamps *TEST BENCH EQUIPMENT* SMD / D'Amore Engineering Amp Dyno (AD-1): is.gd/wccad1 XS Power D1400 Batteries - amzn.to/2BPFCKW XS Power PSC60 Charger - amzn.to/2CHGcfs Fluke 1000A AC/DC Clamp Meter: amzn.to/2Rw5WDA Handheld Dyno AMM-1: is.gd/wccamm1 My Favorite Precision Screwdriver Kit: amzn.to/3RTO6c4 _DISCLAIMER: This video and description contains affiliate links, which means that if you purchase from one of the product links, I may receive a small commission. As an Amazon Associate I earn from qualifying purchases_
If it doesn't bridge in mono mode, then its a pointless feature and a waste of hardware and materials, its about as useful as fly screens on a submarine, im sure its a great little stereo amp, but without bridging, its selling snake oil.
The Fosi site and the TPA3255 data sheet both describe the mono mode as PBTL ... Parallel Bridge Tied Load. This is not a power increasing mode it is a mode that parallels the output channels and lets the chip work on lower impedance loads (2 and 3 ohms, per the data sheet) without destroying itself. The one that wouldn't turn on is worrying.... Wazzup wi' dat? Did it work in stereo mode? Also I'm still waiting to see someone flip that Stereo/Mono switch with music playing... The chip is not designed for "on the fly" reconfiguration so there is a doubt that it's safe to do and that switch is right out in "Daddy what does this do?" territory.
That switch definitely needs to be elsewhere, these companies almost get things right, they haven't made the complete package yet there's always something that is missing or misplaced. Very frustrating
@@crazyprayingmantis5596 Agreed ... It's almost like they have a "department of silly mistakes" to make sure of it. If it was up to me changing modes wold require removing the front cover.
Well, idiot me just did that today messing with cables on the fly. The amp stopped playing, but after a switch off/on, it worked again with apparently no issues, guess I was lucky, idk. However, it can't hurt to put the switch somewhere else and kinda foolproof.
@@34332 Oh man, that could have been a shitty Christmas present, for sure. I'm glad it came back on! But now we know... it's not a safe thing to do while the amp is powered up. I can't offer a guess how often you would get away with that, but I'm thinking you were lucky. Now I wonder if that's why one of the amps failed during Dereck's rather gushy video... Let me be plain here... I like Fosi and it's ambitions to bring excellence to inexpensive audio, but of late I seem to have a habit of calling them out on some pretty serious engineering mistakes... If you look at my other posts you will find one about the TB-10D, where they not only misunderstood the chip's control logic but left the thing in a state where it would actually play music while turned off. Now this stereo/mono thing. I wish I could say I didn't see it coming a mile away, but I did. Even worse is the matter that literally dozens of reviewers extolled the virtues of the TB-10D after Fosi's supposed upgrade... and none of them caught the problems. Not one of them. Not even the guys doing hardware testing caught it. Now, after more than a dozen ZA3 reviews and the only way this one is caught is by accident. This is not good. I'm betting the AO7Max has the same issue, except that they had the common sense to hide the switch in a spot where the kids won't play with it and it's unlikley to be flipped by accident. Dumb mistake Fosi ... really dumb!
The problem is those class D amps are not able to sustain the power for longer periods of time like the class AB amps. Producing high wattage for 1/10th of a second is not a problem but to even maintain half the power at 1 minute will sag the anemic power supply. Physics is physics...
I am curious why you didn't show any results for mono into 2 ohms. That is where there really should be some advantage since things are in parallel. Thanks for all that you do. Even though this is not bridged to get twice the power, there are some real advantages with two separate power supplies and the isolation between channels using separate monoblocks.
They also rated it for mono into 4 ohms and 8 ohms and yet, measurements were taken by Williston Audio Labs to verify Texas Instruments chip rating. So why not take the final measurement for us at 2 ohms as well? The whole purpose of these mono amps is the ability to drive 2 or 3 ohm loads. I would have liked to see the results as I'm sure many others would. Of course, a current output comparison between stereo and mono mode may have been even more revealing. @@SilmarilS79
The MONO mode doesn't bridge the amplifier it puts it into PBTL mode (Parallel bridge tied load) basically putting all the available channels in parallel, this way the amplifier can achieve higher power outputs at lower impedances but it only works under 4 ohms due to ohm's law, if you are using a 4 or 8 ohm load it's basically doing nothing extra vs the normal mode as the resistance is simply not low enough to pass the extra current. So basically, you are better off having 2 channels than one at anything 4 ohms or higher
@@SilmarilS79 i never said anything about 8 ohms Also given the 63v caps you can safely go to 50v however even though the chip is rated at a max of 54.5 i wouldn't go any higher because cooling might become an issue I had an aiyima subwoofer amp based on the 3255 and it also had 63v rail caps, i removed the top cover and installed a small fan to the heatsink and i was powering it from a 52.5v 12.5a PSU running at 2 ohms without issues for my 2 10" subs Good power from it, i still upgraded from it because it wasn't quite enough for 2 10" subs but it served me well.
@@Random_4400 "still upgraded from it because it wasn't quite enough for 2 10" subs but it served me" do you mind telling us, What;s that amp you upgraded to?
Another one jumping on the hype bandwagon. Yes, it is good, but you'll need a DAC. Check the SMSL AO300 ... Comparing both, the SMSL is better, and a bargain with excellent features topped with amazing resolution, power and dynamics. Imaging and depth is seriously impressive. You can safely use it with high end speakers. My power/pre combo costing considerably more has been made redundant. The Fosi is now used in the conservatory.
Love my Fosi Audio BT30D Pro they at least addressed the bluetooth priority by going into connect mode when power cycled, ie it kicks off anyone who stole the bluetooth on the amp. Cheap bluetooth Chinese amps have instant reconnect and no override so if the bluetooth is stolen by another device it won't log off until the offending device either goes out of range or is turned off. I actually checked the BT30D Pro and it has 50V input caps so up to 48V could be used but the overheating problem will pop up. Looks like they finally addressed that too AND balanced inputs for pro audio use. Awesome, only way to make it better would be to add 2.1 amp capability with adjustable low and high pass crossovers, you know like a car amplifier. Also wanted to post because I'm giving Williston Audio Labs a shout out on my channel. Your channel is basically my inspiration for starting my own electronics repair business and youtube channel. My first project is a customizable party tower speaker that people can build themselves. Your channel's testing inspired me to take my 20+ years of pro audio repair experience and show people with amps like you test you can build a party speaker that performs better, costs less, and is repairable and upgradeable rather than say a JBL Partybox 1000 in terms of both power output and sound quality. So thank you Williston Audio Labs. You're truly keeping the big boys honest.
Damn, kinda disappointed in this as i ordered 2. I thought it was bridged inside and would double the power output in mono mode. I guess i will be sending one back 🤷♂️ . You should do a test on the Aiyima A07 Max, that amp in mono mode uses both channels power which makes me wonder if they actually do bridge the amp. 🤔
The amp chip has 4 output channels and is technically running bridged in 2 channel operation. Fosi choose to run the 2 Bridged channels in parallel for mono mode for quality and stability over higher wattage. 2 channel is BTL, mono is PBTL. bridged tied load and parallel bridged tied load
What Josh said^^^ The outputs are already bridged in stereo mode. The mono mode parallels them for more current. The only real advantage of the monoblock setup is that you are using 2 power supplies for increased current output into low impedance loads.
I just thought the power would of came close to double, not 10 to 20 watts over than running in stereo mode. To me it looks like one channel shuts down as if you did the same in stereo mode but unplug one channel. 🤷♂️
@@mattburgess2 First, since the outputs are bridged already in stereo mode you're not going to bridge them again. Thus the output voltage across the speaker _will not change_ If the voltage doesn't change, neither does the wattage. What they are doing is hooking the outputs from the left and right channels together to form one monophonic bridged amplifier. This gives them more current capacity for low impedance loads but doesn't increase power on the more common loads. Where the extra power comes from is lower speaker impedance... For example, if you are running 50 watts on 8 ohms, the same speaker voltage would produce 100 watts on 4 ohms... or 200 watts on 2 ohms. It's that last step that requires the Parallel Bridge Tied Load mode of the chip. So, if like most of us you're using speakers in the 4 - 6 - 8 range you won't get higher power in mono mode.
I love your videos, but you listed no USB for High Rez audio as a negative? It was designed as an amplifier and marketed as such, not a DAC. An external DAC can play any resolution level into this amp just fine. I'm sure you know that, but I was wondering why you listed it as a negative that it didn't have USB for high rez when this is not a DAC? It isn't a FM radio either but you didn't list that as a negative on the power amplifier.
Update: I just added a second one, mono config and both Sparkos chipped. The results are simply amazing... more power yes, but increased dynamics throughout the volume range and the sound-stage and mid-bass are really fantastic. How many watts total...? Mucho. No, you're not gonna host a rave but in a decent sized room you'll be jamming. Full disclosure: PCM input from computer @384, (Fosi SK02) speakers DALI Zensor 3s. Wow. Cheers all and thanks.
the tests are gold - thank you! But to sum it up, it appears there is not much (power) advantage to running these in dual mono mode, right? So why buy/use two? I've seen some comparisons of this amp running in stereo vs dual mono mode, and the latter does sound different - more open and differentiated. But yeah, this is just sampled over youtube with whatever mic's the host usesd, then running through my own less than perfect system. I feel like I have looked into this amp deeply but still know nothing :D
Comparing the max power results of the ZA3 to the V3 shows virtually identical results with the edge actually going to the V3 for most results. The only advantage power wise of the ZA3 in mono is about 10-15 watts over the stereo V3 output. I would guess that if only one channel of the V3 was tested it would be identical to the ZA3 in mono. As I see it the only advantage of the ZA3 is the XLR inputs and 12 volt trigger. I did get the ZA3 and listening to it with my Maggie 1.7 it sounds a bit brighter than my V3. Is this sample to sample variation or did Fosi actually change something in the ZA3 circuit? dunno
They're both based on the same chip. The difference in distortion specs is probably due to the extra Op-Amps (the NE5532 chips are a bit messy). The Mono mode parallels the two stereo channels for more output current. It's no surprise the power ratings are nearly the same.
Mono use will gives you more control of a 2 ohm load than in stereo configuration. Might be better for hard to drive speakers that dips below 4 ohm. Running a 6-8ohm load, it won't matter between stereo/mono.
@@SilmarilS79 I'm actually using the Fosi V3 with my Magneplanar 1.7's (amazing isn't it?) I bought the ZA3 wondering if using it in mono and getting a second one would be worthwhile and it is not for my purposes. Actually the V3 sounds great - currently playing wonderful Christmas Music - Merry Christmas to all.
@ernestojajan1419 I did the same thing , had 2 za3's and tested and compared against my v3. The 2 za3's vs my v3 was only 1 decibel louder but more harsh compared to my V3, to me the V3 sounds much nicer. All the za3 is doing is killing off 1 channel nothing more in my opinion, you can get technical all you want but 1 decibel isn't adding any power increases. Back to back the v3 wins in sound but looses with no sub out.
I got 2 of these. Instead of using mono for each speaker, I set it up as bi Amp. Using left channel for low and right channel for mid and high to power my tower speakers. Sound is amazing!
This is not the best idea due to crosstalk. It's better to use one amplifier for stereo low and second for stereo mid-high if you use an external crossover (a bit of crosstalk between left and right is perfectly fine, between low and high not so much).
@@AdamsOlympia yes I been running it in mono mode bi-wire for past few months. It’s really good. I am considering getting another amp for my center channel. I also considered getting an internal chip upgrade, not sure if its worth it and also for mono do I need one or two per amp?
In case anyone cares, TRS is also balanced. Tip/ring/sleeve. Standard 1/4 connector, TS, tip/sleeve is unbalanced. Most XLR inputs are both XLR and TRS...the hole in the middle is for TRS . :)
@@jimb1580Yes indeed. TRS are a lot cheaper, especially if you want angled plugs for tight spaces - a problem with XLR, as they're usually fixed angle and not simply rotating like TRS. There's also zero mechanical stability difference in a home situation. Both types last forever, the main advantage of XLR is that they lock in and are even more stable. Not a concern at home.
Hehe, XLR is mostly for noise. There is a chance it would not be that noticeable by ear. It requires you to spend a lot attention to what your hearing and most ppl just want to relax to there tunes .
Luckily, I was able to get an Emotiva BasX a2 (class A/B) on sale for $300. I have a lifeless class D amp like the Fosi and use it twice a year (Aiyima a07). Better than nothing.
Thanks for the tests, one thing I noticed is that from Ch. 2 the output registered a little higher than Ch. 1, but when you tested the 8 ohm mono, it was showing results on Ch.2, but when you did the 4 ohm test, it was on Ch.1, so would the 4 ohm mono results be better on Ch. 2 output?
Just a note: they _did_ have two op-amps on the XLRs. The NE5532 is two op-amps in one package. The better question is why they needed 10 total in that amp. Guessing they're doing lots of buffering internally? Maybe input impedance control? 🤷 Still, pretty cool, and good to see a TI TPA at the core.
2 for the XLR differentiators. 2 for the Sub filters then 2 for each channel's phase splitter ... total... 8 op-amps. The extra 2 are in the sub filter... so maybe it's got a really sharp cutoff.
@@c34webb 1 chip ... 2 op-amps. The board is marked. so you know what you're messing with. But if I might suggest, leave that one alone. The differentiators for XLR are a rather sensitive balance. They have to be just so to minimize distortion. Try leaving it alone at first. Change it only if you need to and be prepared to change it back later.
ZA3 has excellent sound. Similar to good headphones on a good headfi amp, but through your speakers. Excellent detail and dynamics. To do better would mean spending $2k+ on an audiophile amp. Class A or A/B. It compares favorable to my Krell KSA 100 through Mirage M3i in 1991. But that cost $5k then.
The trigger cables won't work between two ZA3s, needs one of their amps with a 12V OUT trigger jack. I didn't see your power supply setup for the dual mono test... you were using two PS, right? My dual mono Sparkos-chipped setup is working really nice. Added the Sparkos to the XLR circuit as well and things got even better, even using RCA to XLR conversion cable. Just an update, thanks again as always and cheers from Japan.
What's crazy is that this can be sold for barely north of $100, but the big home audio companies charge anywhere from $400-$1000 for a 100 watt receiver or integrated. C'mon! Do better!
The Mono mode from this ZA3 and Aiyima A07 Max seems to be a gimmicky scam, it's practically putting out the same power as running single channel in stereo mode with absolutely zero benefit, but introduced more distortion (higher THD) in mono @4ohm or less.
I don't get it if you don't get bridging and increase in power why wouldn't you run it laterally for 150% of power-why run two vertically in mono??????
just a new hype - boring. I don't say it is a bad amp, but is there anything new? Better sounding, smaller? 300Watts? At home are 5watts enough to let you bleed out of your ears.
The dogma surrounding XLR connections in HiFi systems seems very durable. Based on what I'm seeing on that PC board, the RCA jacks should offer superior performance.
@@AdamTait-hy2qh, quite honestly for most hifi-applications in residential environments, XLR is very much a nice-to-have for most people. The advantages are larger for longer cable-runs or much noisier environments than a normal living space. If you have long runs of RCA running along power cables or in-walls or such, there's a good case for XLR, but it's rarely necessary for things like hooking up a separate power amp with a cable of a few feet.
So realistically, is there any reason to use these in mono? The power difference doesn't seem that great, so what would be use cases for going mono? I did plan on buying two of these, but I'm having second thoughts now...
Yep... and when sitting on a bench or table likely to pick up lumps of dust that can degrade the cooling quite a bit. Best bet... buy some thermal paste, clean and re-paste every time. The fun part is that unless you want to waste a ton of paste, you need to put a thin line of it inside the case so the heatspreader will pick it up as it moves over it. Putting it on the spreader will just result in a big smear of wasted paste all the way along the case.
@myaudioquest 0 seconds ago I bought the Fosi ZA-3 (with 48V power supply) thinking it might be a keeper. What I discovered was a mixed bag...thin in the mid-range and bass. I also did not care for the volume control, cheap like in build and function. On the plus side is exceptional clarity in the treble but requires a sub-woofer to add body and weight to the music. Best used with a bass centric loudspeaker or possibly use two amplifiers. My two cents!
Or a strong preamp would do the job. I don't get why people are expecting these to perform perfect standalone, you MUST have a decent preamp to get solid performance.
@@JukeboxAlley People are expecting it because it is indeed an integrated amplifier and marketed as such. If it was just a power amplifier, you would have a point.
@@ropeburn6684 it's only marketed as an integrated because it has gain....alot of power amplifiers have gain controls, and their still power amplifiers that need a preamp.
It's funny, I've been making the transition from an at home audio consumer to a live audio professional. My standards for audio playback quality have lowered slightly in the transition but my requirement for inputs has changed DRASTICALLY. As a result, I look to XLR even at the cost of quality/fidelity for compatibility/ease of use with the rest of my equipment. I laugh to see XLR described as "audiophile grade" when half of the interfaces and signal modulators I'd use now in my actual professional career have MUCH shittier integrated circuits like dacs. The paper performance of my rca/ts based audio playback devices are better than the XLR based equipment that I can afford. Like.... Check out how the Scarlett Focusrite 2i2 performs and compare it to half your gear you own. That interface is the Toyota Camry of the professional audio world, with Apollo being like the AMG of it.
Can we PLEASE test the Eton ultra low distortion car amps? Core A2 claims distortion to be .001%. Mobile “hi-res” low distortion monster. Supposedly the absolute best car amp for “hi-res”. Inquiring minds want to know lol. I think it’s like $2000 for a 200w amp so I get the reluctance but a dyno of this amp would probably bring audiophiles to this channel
The on/off cycling of the amp at 2 ohms is no doubt the power supply. The power supply would likely get bogged down a bit even at 4 ohm. A 198 watt 2 ohm load would load the power supply to about 9.9 amps and the voltage would probably droop to about 19.9 volts on the power supply due to current limiting. At almost 10 amps on a 5 amp power supply it would certainly put itself into short circuit protection but I would have thought it would reach full protection before that. The TPA3255 also has over current protection but it is hard to tell which would trigger first without knowing what the circuit set the TPA3255 over current protection to.
honestly i think i ll pass on this one. i prefered the design choices of the v3 alot more aswell. here are some issues i have with it: 1. its actually not all that cheap at all. you can get used integrated for as low as 30 bucks. 2. i pay for stuff i dont need and some of it makes no sense to me either. The za3 is best run with a preamp in front ayways because remote, tone controls and all that so if i use it with a preamp to begin with: i dont need a volume knob on it, i dont need balanced inputs either, i dont plan on using it as a monoblock either because that would put it at a 300$ amp wich defeats its purpose. i pay for features i have no use for. i rather had a super simple barebones power amp thats 100 bucks instead of 150 with no volume knob, no balanced ins, no sub out, nothing. plain simple power amp black box i can hook to my preamp. that would make way more sense to me as a product. i dont really understand the fosi, its kinda semi integrated.. but then its not an integrated either, it really needs to make clear what it wants to be. an integrated? or a plain power amp. stereo amp? or a mono block. and specify in only that and sell different versions of it. 3. also the 150 Euros mark is a really weird one to me because spend a little more and you ll get really nice used amps with so many features, pay less and you get something thats not that much worse. so in that way it makes more sense to me to buy a used sony or yamaha for 30-40bucks and then save up to buy a great amp in a year. 4. resell value. i dont see it here. i had avrs and amps that i sold for more than i payed for them. established brands like yamaha or pioneer or denon or nad they hold their used market value pretty stable. on those fosi? who will buy a za3 used in 1-2 years if fosi allready released 10 new amps by then? 5. i dont like its design. this forced orange look makes it look like a childs toy. the v3 looked way better. i also dont like the volumeknob power button, give me an actual dedicated power button. to me the za3, tries to please too many people and do too much all at once. i dont like that. i like stuff that does one thing and does it really well. i would like fosi to have an entire lineup of matching devices instead. have a dac, a preamp, a tube preamp, a plain stereo power amp, a mono block power amp, and a integrated amp. all matching in design so you have a complete lineup to choose from.
The actual difference in sound from XLR to RCA in a home is minimal at best . I've had gear that had XLR inputs for 30 plus years and although I kind of went all in with headphone amps being balanced I drank the Kool aid and really I'm not sure any of it matters
Would 2 of these with a good preamp behind them be solid and sufficient for a set of klipsch rf7 flagships is the question? Enough low end grunt and control or maybe too much to ask? The rf7 is 97 db sensitivity, has a big impedance dip though, rated at 8 ohms.
I feel like these mini amps usually need some sort of preamp to have enough functionality to be useful for most people. No dac, no Bluetooth, no HDMI, no remote, no phono. There's just not much that people use these days with RCA out. So that just makes cost higher than the list price because it's not terribly useful without some of those features. And at that point why not just buy something a bit nicer that has all of that included? Never quite understood who these are for honestly. I can see them making a great amp for a couple of passive subwoofers for a home theater. Should be enough power for most people. Other than that I'm not really sure. Let me know though what you use yours for I'd be curious.
I had v3, like it but will return it because it pops when turning on. ASR reports that Za3 pops less louder but still pops. Is there any issue with the popping noise? Does yours pop?
I’ve been watching your context for a few years now and I really like your mini amp content. I use mini amps for vinyl and other two channel stuff like streaming. I would love to see much more content like this more from fosi, aiyima, and douk!
Pin 2 is hot for our western audio standard, as shown by the Fosi. That Sony CD player uses the Japanese standard of having pin 3 hot. Using mixed XLR units reverses the phase and hurts bass response unless you have a special XLR cable made for this issue.
TRS and XLR are the same from an electrical and noise reduction standpoint. Just the connectors are different. Don't forget, only attach the shield at one end.
I have some KEF LS50 Meta currently for stereo. I intend to upgrade them to KEF R3 Meta when/if they go on sale. I only have a Yamaha RX-A4A receiver that is rated at 110W/ch. Do you think this amp or any of the new little class D amps will be a significant upgrade to give the KEF a little more volume for Hi-Fi stereo playback?
Based on features and bench testing, the best deal from Fosi is still the TB10D. With a 48 volt 10 amp supply I easily got 220w/ch 0.1% distortion at 4 ohms out of mine. I generally run it at 36 volts where it's got good power but doesn't heat up much. With a couple of simple mods, that distortion figure can be gotten down to 0.03%.
@@MiguelAngelVelazquez Here ya go: As long as you can do some minor SMT soldering it's pretty easy... 1) At the left front corner of the main board there is a zener diode (tagged D1, I believe) that sets the logic control voltage. On the version 2.1 and earlier board it's setting that at 5 volts. You can test the voltage on the centre pin of the power switch. The control logic for the chip is 3.3 volts. You will need to parallel another zener onto the existing one to reduce that voltage for proper operation. I found the right value by experimentation, but IIRC it's 3.9 volts. 2) When off, the reset pin on the TPA3255 (Pin 18) is left floating. This actually allows the chip to remain on with the power switch in the off position. The fix here is to scratch away some of the solder resist, exposing copper on the bottom of the board, at the bottom of the rear leg of the power switch. Now solder bridge that pin to the exposed ground to force the chip to shut down when the switch is off. (Later versions have this done already) 3) The last mod involves a problem with the output coils. They're too close to the main heat sink. This causes all kinds of inductive eddy currents in the heatsink, and cross coupling between the coils which causes all kinds of minor havoc, including inductive heating of the heat sink. The fix here is to remove the heat sink, being careful not to lose the spacers and cut away one fin smooth with the bottom of the second fin, effectively making it one fin smaller on one side. Now, clean up your cut, redo the thermal paste and replace the heatsink so that the missing fin is nearest the coils. This creates about a 1cm gap which is sufficient to avoid most of the inductive coupling. The first two are for longevity of the amp. The last one cleans up the sound quality quite noticeably. Best of luck with it!
@@MiguelAngelVelazquez Just a quick update ... I've just gotten TB10Ds in. The board version is now 2.2. The power switch problem is fixed, that back pin is now firmly grounded as it should have been. The logic voltage is still sitting well above the 3.3 expected. I just read 4.7... so you will need to fix the zener diode controlling that. On the V2.2 board it is at the board edge next to the power switch, tagged as D3. Of course the heatsink is still touching the coils which affects the sound quite noticeably. Comparing the new stock with one of my modded units the bass is a bit boomy, not clear and the highs are less distinct. So cutting one fin off the heatsink is still a viable modification. Hope this helps.
@tikkiu7345 For the distortion figures I asked an associate to run an unmodified unit and one with my mods it through a QuantAsylum analyser. But there's more to this than simple distortion testing. There are issues of over voltage supplies and heat that also need fixing.
$100 would be a better price. I would love to see Fosi audio to make just a multi-filter(Lowpass/highpass) unit with phase adjust knob and switch for freq slopes 24dB/oct and 12dB/oct...
Thanks for the video review! One thing that is confusing, which you partially glossed over, then dismissed altogether is the fact that the measured output power and the available power from the included AC power supply bear no resemblance to one another. It would be great if you could follow through with your train of thought and explain why the numbers are so vastly different. When I make technical measurements and something is out of whack, I dismiss the measurements and figure out what I did wrong in performing the tests, then fix it before publishing it. I have been following this "mini-Class-D" amp market for a while and have yet to see one amp where these kinds of advertised numbers match up. Things like "Our 600W amp only requires a 108W supply! How? It's magic! Just trust us....honest!" I continue to remain unconvinced. One last thing is that when an amp has XLR inputs, the pinouts are in the manual. The reason is that there is more than one standard convention for wiring up XLRs. Also - the connector appears to accept 1/4" plugs, which is not mentioned. Hmmm... Best thing so far is that it's so ding dang cute! So cute that it needs a Hello Kitty sticker on it. Technically...I'd keep shopping.
The answer is simple: the power supply is conservatively rated. It can actually put out more than 5A for a short time. I've read online that people tested it and it went to a good 7A without shutting down, which is consistent with the measurements in the video. Of course the advertised "2x300W omg lol" is still grossly exaggerated. It's a theoretical 10% THD power with the chip driven to maximum specification (52V 12A or something like that), and not possible with the device at hand and the available power supplies. Much like you, I wish they changed their advertising towards more honesty. "2x150W @ 4Ohm with 48V supply" is still impressive enough for my taste and a tiny amp this cheap, and wouldn't stop me from considering buying it at all.
@@ropeburn6684 I bought one of these little amps and I would not use it all of the way up, but all of the manufacturers lie in their specs. It's a fun phenomenon to watch. People gobble this stuff right up! "I got a gigawatt out of the amp using a single penlight cell!"
@@ropeburn6684 7A sustained, or just for a few milliseconds? I'm not complaining, but people who are agreeing with the comical claims from the manufacturers make themselves look slightly silly. While I did buy one of these things (a 2.1), it was about $40, so I don't feel badly if it sounds lousy. I don't expect much from it. It's only for travel use and it will be battery powered @ ~22V. anyway, this little industry is fun to watch. Lots of online people say that these cheap Class-D amps will take over the world and sound better than Macintoshes.
Hopefully I won't have to remove it as the track itself is public domain, but not sure about the Telarc recording. I had a lot of fun listing to a ton of CD's with this setup! Too bad the experience cannot be shared over RUclips
That looks like a Nice desktop solution. This looks like the type of thing that will be good for somebody that's going to college and living in an apartment or a dorm.
Hi! Stupid question but how would you wire it in a setup with an additional central speaker? I really love my old NAD... It gives a LOT in terms of soundstage vs most amps I tried. Perhaps this mini amp could be interesting to add. (btw, what music did you use for the test?)
In Pro audio, TRS is balanced, just like XLR. Audiophiles be trippin and are the craziest customers to have when doing audio repair. Like being able to think you can hear the difference between different coupling capacitors. As long as they are in spec and used within spec, you will never hear the difference.
I did not pay for the amp but this doesn’t matter as I have more amps than I need and my goal is to share the info for others and not to promote any amplifier brand
_Note: Amp is SOLD OUT as of December 24, 2023 due to incredible demand. It should be in stock again in a few weeks_
*SHOP for the ZA3 Here* amzn.to/41zmrjT
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Elac Debut 2.0 B6.2 Bookshelf Speakers: amzn.to/3Mmdbcz
*RELATED VIDEOS*
Fosi Audio V3 Review: ruclips.net/video/U0JwSR0yS_A/видео.html
Fosi Audio BT20A-PRO Review - ruclips.net/video/b1zFuLK655g/видео.html
More Power in than Out? ruclips.net/video/c7QELbpKMuI/видео.html
Mini Amps Video Playlist - is.gd/walminiamps
*TEST BENCH EQUIPMENT*
SMD / D'Amore Engineering Amp Dyno (AD-1): is.gd/wccad1
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What about the remote?
Thanks for the link...but it is SOLD OUT
Can you provide a paylist for the songs that you have used?
Will this thing handle 60 volts? Thinking about putting a stereo on my 5600w electric scooter
@@buddsmokengood
No. 48 max ...
If it doesn't bridge in mono mode, then its a pointless feature and a waste of hardware and materials, its about as useful as fly screens on a submarine, im sure its a great little stereo amp, but without bridging, its selling snake oil.
The Fosi site and the TPA3255 data sheet both describe the mono mode as PBTL ... Parallel Bridge Tied Load. This is not a power increasing mode it is a mode that parallels the output channels and lets the chip work on lower impedance loads (2 and 3 ohms, per the data sheet) without destroying itself.
The one that wouldn't turn on is worrying.... Wazzup wi' dat? Did it work in stereo mode?
Also I'm still waiting to see someone flip that Stereo/Mono switch with music playing... The chip is not designed for "on the fly" reconfiguration so there is a doubt that it's safe to do and that switch is right out in "Daddy what does this do?" territory.
That switch definitely needs to be elsewhere, these companies almost get things right, they haven't made the complete package yet there's always something that is missing or misplaced.
Very frustrating
@@crazyprayingmantis5596
Agreed ... It's almost like they have a "department of silly mistakes" to make sure of it.
If it was up to me changing modes wold require removing the front cover.
@@Douglas_Blake_579 or maybe a recessed switch in the rear.
Well, idiot me just did that today messing with cables on the fly. The amp stopped playing, but after a switch off/on, it worked again with apparently no issues, guess I was lucky, idk. However, it can't hurt to put the switch somewhere else and kinda foolproof.
@@34332
Oh man, that could have been a shitty Christmas present, for sure. I'm glad it came back on!
But now we know... it's not a safe thing to do while the amp is powered up. I can't offer a guess how often you would get away with that, but I'm thinking you were lucky. Now I wonder if that's why one of the amps failed during Dereck's rather gushy video...
Let me be plain here... I like Fosi and it's ambitions to bring excellence to inexpensive audio, but of late I seem to have a habit of calling them out on some pretty serious engineering mistakes... If you look at my other posts you will find one about the TB-10D, where they not only misunderstood the chip's control logic but left the thing in a state where it would actually play music while turned off. Now this stereo/mono thing. I wish I could say I didn't see it coming a mile away, but I did.
Even worse is the matter that literally dozens of reviewers extolled the virtues of the TB-10D after Fosi's supposed upgrade... and none of them caught the problems. Not one of them. Not even the guys doing hardware testing caught it. Now, after more than a dozen ZA3 reviews and the only way this one is caught is by accident. This is not good.
I'm betting the AO7Max has the same issue, except that they had the common sense to hide the switch in a spot where the kids won't play with it and it's unlikley to be flipped by accident.
Dumb mistake Fosi ... really dumb!
but no remote control..
The problem is those class D amps are not able to sustain the power for longer periods of time like the class AB amps. Producing high wattage for 1/10th of a second is not a problem but to even maintain half the power at 1 minute will sag the anemic power supply. Physics is physics...
I am curious why you didn't show any results for mono into 2 ohms. That is where there really should be some advantage since things are in parallel. Thanks for all that you do. Even though this is not bridged to get twice the power, there are some real advantages with two separate power supplies and the isolation between channels using separate monoblocks.
Texas Instrument rated the chip in PBTL mode for 2 ohm loads.
They also rated it for mono into 4 ohms and 8 ohms and yet, measurements were taken by Williston Audio Labs to verify Texas Instruments chip rating. So why not take the final measurement for us at 2 ohms as well? The whole purpose of these mono amps is the ability to drive 2 or 3 ohm loads. I would have liked to see the results as I'm sure many others would.
Of course, a current output comparison between stereo and mono mode may have been even more revealing. @@SilmarilS79
It's safe to assume 2ohm Mono isn't going to be too far off from @200w and dynamically around 260~280w.
The MONO mode doesn't bridge the amplifier it puts it into PBTL mode (Parallel bridge tied load) basically putting all the available channels in parallel, this way the amplifier can achieve higher power outputs at lower impedances but it only works under 4 ohms due to ohm's law, if you are using a 4 or 8 ohm load it's basically doing nothing extra vs the normal mode as the resistance is simply not low enough to pass the extra current.
So basically, you are better off having 2 channels than one at anything 4 ohms or higher
The amp chip is voltage limited to 48v, so it won't make more power at 8 ohm.
@@SilmarilS79 i never said anything about 8 ohms
Also given the 63v caps you can safely go to 50v however even though the chip is rated at a max of 54.5 i wouldn't go any higher because cooling might become an issue
I had an aiyima subwoofer amp based on the 3255 and it also had 63v rail caps, i removed the top cover and installed a small fan to the heatsink and i was powering it from a 52.5v 12.5a PSU running at 2 ohms without issues for my 2 10" subs
Good power from it, i still upgraded from it because it wasn't quite enough for 2 10" subs but it served me well.
@@Random_4400 "still upgraded from it because it wasn't quite enough for 2 10" subs but it served me" do you mind telling us, What;s that amp you upgraded to?
Another one jumping on the hype bandwagon.
Yes, it is good, but you'll need a DAC.
Check the SMSL AO300 ... Comparing both, the SMSL is better, and a bargain with excellent features topped with amazing resolution, power and dynamics. Imaging and depth is seriously impressive.
You can safely use it with high end speakers.
My power/pre combo costing considerably more has been made redundant.
The Fosi is now used in the conservatory.
Love my Fosi Audio BT30D Pro they at least addressed the bluetooth priority by going into connect mode when power cycled, ie it kicks off anyone who stole the bluetooth on the amp. Cheap bluetooth Chinese amps have instant reconnect and no override so if the bluetooth is stolen by another device it won't log off until the offending device either goes out of range or is turned off.
I actually checked the BT30D Pro and it has 50V input caps so up to 48V could be used but the overheating problem will pop up. Looks like they finally addressed that too AND balanced inputs for pro audio use. Awesome, only way to make it better would be to add 2.1 amp capability with adjustable low and high pass crossovers, you know like a car amplifier.
Also wanted to post because I'm giving Williston Audio Labs a shout out on my channel. Your channel is basically my inspiration for starting my own electronics repair business and youtube channel. My first project is a customizable party tower speaker that people can build themselves. Your channel's testing inspired me to take my 20+ years of pro audio repair experience and show people with amps like you test you can build a party speaker that performs better, costs less, and is repairable and upgradeable rather than say a JBL Partybox 1000 in terms of both power output and sound quality.
So thank you Williston Audio Labs. You're truly keeping the big boys honest.
Going to check out your channel since my uncle wants to buy that jbl Bluetooth speaker
Christ everyones shilling this amp lol
Damn, kinda disappointed in this as i ordered 2. I thought it was bridged inside and would double the power output in mono mode. I guess i will be sending one back 🤷♂️ .
You should do a test on the Aiyima A07 Max, that amp in mono mode uses both channels power which makes me wonder if they actually do bridge the amp. 🤔
The amp chip has 4 output channels and is technically running bridged in 2 channel operation. Fosi choose to run the 2 Bridged channels in parallel for mono mode for quality and stability over higher wattage. 2 channel is BTL, mono is PBTL. bridged tied load and parallel bridged tied load
What Josh said^^^
The outputs are already bridged in stereo mode. The mono mode parallels them for more current.
The only real advantage of the monoblock setup is that you are using 2 power supplies for increased current output into low impedance loads.
I just thought the power would of came close to double, not 10 to 20 watts over than running in stereo mode. To me it looks like one channel shuts down as if you did the same in stereo mode but unplug one channel. 🤷♂️
@@mattburgess2
First, since the outputs are bridged already in stereo mode you're not going to bridge them again. Thus the output voltage across the speaker _will not change_ If the voltage doesn't change, neither does the wattage.
What they are doing is hooking the outputs from the left and right channels together to form one monophonic bridged amplifier. This gives them more current capacity for low impedance loads but doesn't increase power on the more common loads.
Where the extra power comes from is lower speaker impedance...
For example, if you are running 50 watts on 8 ohms, the same speaker voltage would produce 100 watts on 4 ohms... or 200 watts on 2 ohms. It's that last step that requires the Parallel Bridge Tied Load mode of the chip.
So, if like most of us you're using speakers in the 4 - 6 - 8 range you won't get higher power in mono mode.
I think I understand now, thank you
Only want 2.1 amps. Also needs earc.
I love your videos, but you listed no USB for High Rez audio as a negative? It was designed as an amplifier and marketed as such, not a DAC. An external DAC can play any resolution level into this amp just fine. I'm sure you know that, but I was wondering why you listed it as a negative that it didn't have USB for high rez when this is not a DAC? It isn't a FM radio either but you didn't list that as a negative on the power amplifier.
You killed me smallz with that Grey poupon reference!! 😂😂😂😂
Update: I just added a second one, mono config and both Sparkos chipped. The results are simply amazing... more power yes, but increased dynamics throughout the volume range and the sound-stage and mid-bass are really fantastic.
How many watts total...? Mucho. No, you're not gonna host a rave but in a decent sized room you'll be jamming.
Full disclosure: PCM input from computer @384, (Fosi SK02) speakers DALI Zensor 3s.
Wow.
Cheers all and thanks.
Hi , What pre amp you are using ?
@@RanTausi Preamp is the Fosi SK02, sources: PC PCM @384/32 bit and a Cambridge Audio CD player optical connection.
Looks great...but a bit concerned about getting a dead unit sent out to you.
the tests are gold - thank you! But to sum it up, it appears there is not much (power) advantage to running these in dual mono mode, right? So why buy/use two? I've seen some comparisons of this amp running in stereo vs dual mono mode, and the latter does sound different - more open and differentiated. But yeah, this is just sampled over youtube with whatever mic's the host usesd, then running through my own less than perfect system. I feel like I have looked into this amp deeply but still know nothing :D
I don't like "audiophools" but let's be real, I doubt they'd even want to waste their time with something like this.
Comparing the max power results of the ZA3 to the V3 shows virtually identical results with the edge actually going to the V3 for most results. The only advantage power wise of the ZA3 in mono is about 10-15 watts over the stereo V3 output. I would guess that if only one channel of the V3 was tested it would be identical to the ZA3 in mono. As I see it the only advantage of the ZA3 is the XLR inputs and 12 volt trigger. I did get the ZA3 and listening to it with my Maggie 1.7 it sounds a bit brighter than my V3. Is this sample to sample variation or did Fosi actually change something in the ZA3 circuit? dunno
They're both based on the same chip. The difference in distortion specs is probably due to the extra Op-Amps (the NE5532 chips are a bit messy).
The Mono mode parallels the two stereo channels for more output current. It's no surprise the power ratings are nearly the same.
Mono use will gives you more control of a 2 ohm load than in stereo configuration. Might be better for hard to drive speakers that dips below 4 ohm. Running a 6-8ohm load, it won't matter between stereo/mono.
@@SilmarilS79
The only real difference at 6 and 8 ohms is the chip will run a bit cooler in Mono mode.
@@SilmarilS79 I'm actually using the Fosi V3 with my Magneplanar 1.7's (amazing isn't it?) I bought the ZA3 wondering if using it in mono and getting a second one would be worthwhile and it is not for my purposes. Actually the V3 sounds great - currently playing wonderful Christmas Music - Merry Christmas to all.
@ernestojajan1419 I did the same thing , had 2 za3's and tested and compared against my v3. The 2 za3's vs my v3 was only 1 decibel louder but more harsh compared to my V3, to me the V3 sounds much nicer. All the za3 is doing is killing off 1 channel nothing more in my opinion, you can get technical all you want but 1 decibel isn't adding any power increases. Back to back the v3 wins in sound but looses with no sub out.
Even a cheap remote would be nice. Pretty nice Fosi product.
I got 2 of these. Instead of using mono for each speaker, I set it up as bi Amp. Using left channel for low and right channel for mid and high to power my tower speakers. Sound is amazing!
Hi! Do you have a diagram for such wiring please? Woukd you know how to also add a Subwoofer to the setup in this case? Thank you
This is not the best idea due to crosstalk. It's better to use one amplifier for stereo low and second for stereo mid-high if you use an external crossover (a bit of crosstalk between left and right is perfectly fine, between low and high not so much).
@@jd5787dude a lot of home audio amps are bi amp ready. What he is doing is ideal.
@@AdamsOlympia yes I been running it in mono mode bi-wire for past few months. It’s really good. I am considering getting another amp for my center channel. I also considered getting an internal chip upgrade, not sure if its worth it and also for mono do I need one or two per amp?
@Zeck88522 Sorry...this doesn't make sense....
In case anyone cares, TRS is also balanced. Tip/ring/sleeve. Standard 1/4 connector, TS, tip/sleeve is unbalanced. Most XLR inputs are both XLR and TRS...the hole in the middle is for TRS . :)
If they wired it up correctly, inserting a TS to RCA cord should also work as an unbalanced input.
Wow! Thank you for the reminder. It's easy to start thinking in terms of big fat XLR cords and overlook TRS connectors. 👌
@@jimb1580Yes indeed. TRS are a lot cheaper, especially if you want angled plugs for tight spaces - a problem with XLR, as they're usually fixed angle and not simply rotating like TRS. There's also zero mechanical stability difference in a home situation. Both types last forever, the main advantage of XLR is that they lock in and are even more stable. Not a concern at home.
“…power sackled oaf an ohn…” Love the southern accent Big D!🤠
Hehe, XLR is mostly for noise. There is a chance it would not be that noticeable by ear. It requires you to spend a lot attention to what your hearing and most ppl just want to relax to there tunes .
Luckily, I was able to get an Emotiva BasX a2 (class A/B) on sale for $300. I have a lifeless class D amp like the Fosi and use it twice a year (Aiyima a07). Better than nothing.
Mono appears to be a total waste of money then why even offer it
It benefits low impedance loads- go check out cheap audio man's review as he has a good demo of it.
@@jbrc1322 Thank you for explaining. Amazing power from this tiny box.
A mono setup also offers audible benefits and less to none crosstalk issues. Also see Z-reviews.
Thanks for the tests, one thing I noticed is that from Ch. 2 the output registered a little higher than Ch. 1, but when you tested the 8 ohm mono, it was showing results on Ch.2, but when you did the 4 ohm test, it was on Ch.1, so would the 4 ohm mono results be better on Ch. 2 output?
Likely those are just "per-run" testing errors. It happens.
Just a note: they _did_ have two op-amps on the XLRs. The NE5532 is two op-amps in one package. The better question is why they needed 10 total in that amp. Guessing they're doing lots of buffering internally? Maybe input impedance control? 🤷 Still, pretty cool, and good to see a TI TPA at the core.
2 for the XLR differentiators. 2 for the Sub filters then 2 for each channel's phase splitter ... total... 8 op-amps. The extra 2 are in the sub filter... so maybe it's got a really sharp cutoff.
Interesting. Thank you for the breakdown. @@Douglas_Blake_579
So if you were to swap the op-amp for the xlrs would you need one or 2?
2 op-amps, but only 1 chip package. @@c34webb
@@c34webb
1 chip ... 2 op-amps.
The board is marked. so you know what you're messing with.
But if I might suggest, leave that one alone. The differentiators for XLR are a rather sensitive balance. They have to be just so to minimize distortion. Try leaving it alone at first. Change it only if you need to and be prepared to change it back later.
Damn, I wanted to hear Bachbusters. I've been listening to that cd since it came out.
ZA3 has excellent sound.
Similar to good headphones on a good headfi amp, but through your speakers.
Excellent detail and dynamics.
To do better would mean spending $2k+ on an audiophile amp. Class A or A/B.
It compares favorable to my Krell KSA 100 through Mirage M3i in 1991.
But that cost $5k then.
I have just received the P3 preamp, it is very nice, I wish it had a remote control at least for the volume.
The trigger cables won't work between two ZA3s, needs one of their amps with a 12V OUT trigger jack.
I didn't see your power supply setup for the dual mono test... you were using two PS, right?
My dual mono Sparkos-chipped setup is working really nice. Added the Sparkos to the XLR circuit as well and things got even better, even using RCA to XLR conversion cable.
Just an update, thanks again as always and cheers from Japan.
What's crazy is that this can be sold for barely north of $100, but the big home audio companies charge anywhere from $400-$1000 for a 100 watt receiver or integrated. C'mon! Do better!
The Mono mode from this ZA3 and Aiyima A07 Max seems to be a gimmicky scam, it's practically putting out the same power as running single channel in stereo mode with absolutely zero benefit, but introduced more distortion (higher THD) in mono @4ohm or less.
I don't get it if you don't get bridging and increase in power why wouldn't you run it laterally for 150% of power-why run two vertically in mono??????
just a new hype - boring. I don't say it is a bad amp, but is there anything new? Better sounding, smaller? 300Watts? At home are 5watts enough to let you bleed out of your ears.
The dogma surrounding XLR connections in HiFi systems seems very durable. Based on what I'm seeing on that PC board, the RCA jacks should offer superior performance.
Unbalanced is subject to noise from errant electromagnetic sources. Balanced is not. It is not dogma, it is a technical solution.
@@AdamTait-hy2qh, quite honestly for most hifi-applications in residential environments, XLR is very much a nice-to-have for most people. The advantages are larger for longer cable-runs or much noisier environments than a normal living space.
If you have long runs of RCA running along power cables or in-walls or such, there's a good case for XLR, but it's rarely necessary for things like hooking up a separate power amp with a cable of a few feet.
@@AdamTait-hy2qh Try measuring/hearing that noise on a 1M interconnect and compare that to the noise floor of the equipment and recording.
The maximum power ratings for these amplifiers are usually for 48v 12a psus where in my teating in mono it slightly exceeds the power ratings.
Allowing for a 3DB headroom this is actually a 50W per channel amp at 8 ohms.
Ahh the good old TELARC CD, loved that label!
Love that 7ES player, I have it's little brother 5ES and it still blows minds. What ever you do.. don't sell it ;)
I don't plan on letting it go. Have the original box, manual, remote and it's such a nice piece and the sound is amazing
I have the 5es also weights a ton eh..problem being the laser failed after many moons and cannot get a replacement..bugger
Thanks for the review!
So weird that it doesn't bridge with mono mode regardless of power rating 😅
Next stop Aiyima A07 MAX?🎉
It's already bridged in stereo mode.
TRS IS balanced
... Or Stereo ... or wired up completely wrong ....
So realistically, is there any reason to use these in mono? The power difference doesn't seem that great, so what would be use cases for going mono? I did plan on buying two of these, but I'm having second thoughts now...
The best use case would be for very low impedance speakers, under 4 ohms.
@@Douglas_Blake_579 Thanks. That won't be my use case, so I'll just stick with one and put the rest into an svs sub. 👍
@@NWGR
Sure thing ... and a pretty good choice too.
Heat Sink Paste disturbed when opened?
Reggae, Funk & Brass 🔈🔉🔊
Yep... and when sitting on a bench or table likely to pick up lumps of dust that can degrade the cooling quite a bit. Best bet... buy some thermal paste, clean and re-paste every time. The fun part is that unless you want to waste a ton of paste, you need to put a thin line of it inside the case so the heatspreader will pick it up as it moves over it. Putting it on the spreader will just result in a big smear of wasted paste all the way along the case.
@@Douglas_Blake_579
Good info, tx!
Can I send you a soundtown pro amplifier because I’m curious how much power it’s putting out
Good ole Bachbusters at the end! Tocata and Fugue in D Minor! Gotta love Don Dorsey!
You should hear tocata and b by bass mekanik- I think that’s how he spells it…
A Big D video on Christmas eve!
And another great mini amp review too
I'm also doing 8 videos straight on my Old School Stereo YT channel starting tomorrow! An old school amp test each day for 7 days!
Can’t wait for those videos Big D!!! Thanks for the early Christmas present!!! May God bless you my brother!
@myaudioquest
0 seconds ago
I bought the Fosi ZA-3 (with 48V power supply) thinking it might be a keeper. What I discovered was a mixed bag...thin in the mid-range and bass. I also did not care for the volume control, cheap like in build and function. On the plus side is exceptional clarity in the treble but requires a sub-woofer to add body and weight to the music. Best used with a bass centric loudspeaker or possibly use two amplifiers. My two cents!
Or a strong preamp would do the job. I don't get why people are expecting these to perform perfect standalone, you MUST have a decent preamp to get solid performance.
@@JukeboxAlley People are expecting it because it is indeed an integrated amplifier and marketed as such. If it was just a power amplifier, you would have a point.
@@ropeburn6684 it's only marketed as an integrated because it has gain....alot of power amplifiers have gain controls, and their still power amplifiers that need a preamp.
Cool nice mini amp👍👍👍
It's funny, I've been making the transition from an at home audio consumer to a live audio professional. My standards for audio playback quality have lowered slightly in the transition but my requirement for inputs has changed DRASTICALLY. As a result, I look to XLR even at the cost of quality/fidelity for compatibility/ease of use with the rest of my equipment.
I laugh to see XLR described as "audiophile grade" when half of the interfaces and signal modulators I'd use now in my actual professional career have MUCH shittier integrated circuits like dacs. The paper performance of my rca/ts based audio playback devices are better than the XLR based equipment that I can afford. Like.... Check out how the Scarlett Focusrite 2i2 performs and compare it to half your gear you own. That interface is the Toyota Camry of the professional audio world, with Apollo being like the AMG of it.
Can we PLEASE test the Eton ultra low distortion car amps? Core A2 claims distortion to be .001%. Mobile “hi-res” low distortion monster. Supposedly the absolute best car amp for “hi-res”. Inquiring minds want to know lol. I think it’s like $2000 for a 200w amp so I get the reluctance but a dyno of this amp would probably bring audiophiles to this channel
The on/off cycling of the amp at 2 ohms is no doubt the power supply. The power supply would likely get bogged down a bit even at 4 ohm. A 198 watt 2 ohm load would load the power supply to about 9.9 amps and the voltage would probably droop to about 19.9 volts on the power supply due to current limiting. At almost 10 amps on a 5 amp power supply it would certainly put itself into short circuit protection but I would have thought it would reach full protection before that. The TPA3255 also has over current protection but it is hard to tell which would trigger first without knowing what the circuit set the TPA3255 over current protection to.
honestly i think i ll pass on this one. i prefered the design choices of the v3 alot more aswell.
here are some issues i have with it:
1. its actually not all that cheap at all. you can get used integrated for as low as 30 bucks.
2. i pay for stuff i dont need and some of it makes no sense to me either. The za3 is best run with a preamp in front ayways because remote, tone controls and all that so if i use it with a preamp to begin with: i dont need a volume knob on it, i dont need balanced inputs either, i dont plan on using it as a monoblock either because that would put it at a 300$ amp wich defeats its purpose. i pay for features i have no use for. i rather had a super simple barebones power amp thats 100 bucks instead of 150 with no volume knob, no balanced ins, no sub out, nothing. plain simple power amp black box i can hook to my preamp. that would make way more sense to me as a product. i dont really understand the fosi, its kinda semi integrated.. but then its not an integrated either, it really needs to make clear what it wants to be. an integrated? or a plain power amp. stereo amp? or a mono block. and specify in only that and sell different versions of it.
3. also the 150 Euros mark is a really weird one to me because spend a little more and you ll get really nice used amps with so many features, pay less and you get something thats not that much worse. so in that way it makes more sense to me to buy a used sony or yamaha for 30-40bucks and then save up to buy a great amp in a year.
4. resell value. i dont see it here. i had avrs and amps that i sold for more than i payed for them. established brands like yamaha or pioneer or denon or nad they hold their used market value pretty stable. on those fosi? who will buy a za3 used in 1-2 years if fosi allready released 10 new amps by then?
5. i dont like its design. this forced orange look makes it look like a childs toy. the v3 looked way better. i also dont like the volumeknob power button, give me an actual dedicated power button.
to me the za3, tries to please too many people and do too much all at once. i dont like that. i like stuff that does one thing and does it really well. i would like fosi to have an entire lineup of matching devices instead. have a dac, a preamp, a tube preamp, a plain stereo power amp, a mono block power amp, and a integrated amp. all matching in design so you have a complete lineup to choose from.
The actual difference in sound from XLR to RCA in a home is minimal at best .
I've had gear that had XLR inputs for 30 plus years and although I kind of went all in with headphone amps being balanced I drank the Kool aid and really I'm not sure any of it matters
The TRS comment makes no sense. You can have balanced TRS, it will just carry a mono signal just like XLR does. Audiophiles smh
Would 2 of these with a good preamp behind them be solid and sufficient for a set of klipsch rf7 flagships is the question? Enough low end grunt and control or maybe too much to ask? The rf7 is 97 db sensitivity, has a big impedance dip though, rated at 8 ohms.
I=E/R. 14.22v/8ohms=1.7775amps 1.7775 amps x 14.22volts=25.27watts What kind of tester can be jimmied to give the inflated watt reading yours had?
I feel like these mini amps usually need some sort of preamp to have enough functionality to be useful for most people. No dac, no Bluetooth, no HDMI, no remote, no phono. There's just not much that people use these days with RCA out. So that just makes cost higher than the list price because it's not terribly useful without some of those features. And at that point why not just buy something a bit nicer that has all of that included? Never quite understood who these are for honestly. I can see them making a great amp for a couple of passive subwoofers for a home theater. Should be enough power for most people. Other than that I'm not really sure. Let me know though what you use yours for I'd be curious.
I had v3, like it but will return it because it pops when turning on. ASR reports that Za3 pops less louder but still pops. Is there any issue with the popping noise? Does yours pop?
This model is good to music? Price now?
No wifi? Thats a definition go for me. I bought a really great mini amp off Amazon with wifi for airplay. Works amazing
I’ve been watching your context for a few years now and I really like your mini amp content. I use mini amps for vinyl and other two channel stuff like streaming. I would love to see much more content like this more from fosi, aiyima, and douk!
can you say shill
Can u please test out zeroflex 12k please ive been using i wanna know how much im wattage its producing as its a popular brand in newzealand
could it power my 2 little vintage GE speakers?
Would you pair this up with a DAC? Or is it not recommended for headphones??
If so any recommendations??
Hi everyone, how will this amp perform with a Acoustic Research AR-3A. ?
That is not the best sounding mini amp, the Bru5 is leaps and bounds above it. It has a full dsp built in. That's the one you should test.
Pin 2 is hot for our western audio standard, as shown by the Fosi. That Sony CD player uses the Japanese standard of having pin 3 hot. Using mixed XLR units reverses the phase and hurts bass response unless you have a special XLR cable made for this issue.
What does the trigger thing do?
💥 🔫 ❔
TRS and XLR are the same from an electrical and noise reduction standpoint. Just the connectors are different. Don't forget, only attach the shield at one end.
ALWAYS attach the shield at both ends unless you want to build an antenna.
No balance knob....but why though.
I have some KEF LS50 Meta currently for stereo. I intend to upgrade them to KEF R3 Meta when/if they go on sale. I only have a Yamaha RX-A4A receiver that is rated at 110W/ch. Do you think this amp or any of the new little class D amps will be a significant upgrade to give the KEF a little more volume for Hi-Fi stereo playback?
The truth ... "No" ... until your Yamaha breaks it should be just fine for your needs.
Don know your price there. Happy that in China only cost me $100.
Based on features and bench testing, the best deal from Fosi is still the TB10D.
With a 48 volt 10 amp supply I easily got 220w/ch 0.1% distortion at 4 ohms out of mine. I generally run it at 36 volts where it's got good power but doesn't heat up much. With a couple of simple mods, that distortion figure can be gotten down to 0.03%.
Hello, Doug. Can you provide details about those mods?
@@MiguelAngelVelazquez
Here ya go:
As long as you can do some minor SMT soldering it's pretty easy...
1) At the left front corner of the main board there is a zener diode (tagged D1, I believe) that sets the logic control voltage. On the version 2.1 and earlier board it's setting that at 5 volts. You can test the voltage on the centre pin of the power switch. The control logic for the chip is 3.3 volts. You will need to parallel another zener onto the existing one to reduce that voltage for proper operation. I found the right value by experimentation, but IIRC it's 3.9 volts.
2) When off, the reset pin on the TPA3255 (Pin 18) is left floating. This actually allows the chip to remain on with the power switch in the off position. The fix here is to scratch away some of the solder resist, exposing copper on the bottom of the board, at the bottom of the rear leg of the power switch. Now solder bridge that pin to the exposed ground to force the chip to shut down when the switch is off. (Later versions have this done already)
3) The last mod involves a problem with the output coils. They're too close to the main heat sink. This causes all kinds of inductive eddy currents in the heatsink, and cross coupling between the coils which causes all kinds of minor havoc, including inductive heating of the heat sink. The fix here is to remove the heat sink, being careful not to lose the spacers and cut away one fin smooth with the bottom of the second fin, effectively making it one fin smaller on one side. Now, clean up your cut, redo the thermal paste and replace the heatsink so that the missing fin is nearest the coils. This creates about a 1cm gap which is sufficient to avoid most of the inductive coupling.
The first two are for longevity of the amp. The last one cleans up the sound quality quite noticeably.
Best of luck with it!
@@MiguelAngelVelazquez
Also note ... these mods apply to the TB10D *only* .
@@MiguelAngelVelazquez
Just a quick update ... I've just gotten TB10Ds in.
The board version is now 2.2.
The power switch problem is fixed, that back pin is now firmly grounded as it should have been.
The logic voltage is still sitting well above the 3.3 expected. I just read 4.7... so you will need to fix the zener diode controlling that. On the V2.2 board it is at the board edge next to the power switch, tagged as D3.
Of course the heatsink is still touching the coils which affects the sound quite noticeably. Comparing the new stock with one of my modded units the bass is a bit boomy, not clear and the highs are less distinct. So cutting one fin off the heatsink is still a viable modification.
Hope this helps.
@tikkiu7345
For the distortion figures I asked an associate to run an unmodified unit and one with my mods it through a QuantAsylum analyser.
But there's more to this than simple distortion testing. There are issues of over voltage supplies and heat that also need fixing.
$100 would be a better price. I would love to see Fosi audio to make just a multi-filter(Lowpass/highpass) unit with phase adjust knob and switch for freq slopes 24dB/oct and 12dB/oct...
This is why I wanted to put of my purchase until after it was launched. Thanks.
The power supply becomes the limit here I feel like?
Imagine a version 2.0 with just HDMI input to connect to tv arc hdmi to control with tv remote
For 150 bucks? Hell for 179 u van get a 3k Brazilian.
Thanks for the video review! One thing that is confusing, which you partially glossed over, then dismissed altogether is the fact that the measured output power and the available power from the included AC power supply bear no resemblance to one another. It would be great if you could follow through with your train of thought and explain why the numbers are so vastly different. When I make technical measurements and something is out of whack, I dismiss the measurements and figure out what I did wrong in performing the tests, then fix it before publishing it. I have been following this "mini-Class-D" amp market for a while and have yet to see one amp where these kinds of advertised numbers match up. Things like "Our 600W amp only requires a 108W supply! How? It's magic! Just trust us....honest!"
I continue to remain unconvinced. One last thing is that when an amp has XLR inputs, the pinouts are in the manual. The reason is that there is more than one standard convention for wiring up XLRs. Also - the connector appears to accept 1/4" plugs, which is not mentioned. Hmmm...
Best thing so far is that it's so ding dang cute! So cute that it needs a Hello Kitty sticker on it. Technically...I'd keep shopping.
The answer is simple: the power supply is conservatively rated. It can actually put out more than 5A for a short time. I've read online that people tested it and it went to a good 7A without shutting down, which is consistent with the measurements in the video.
Of course the advertised "2x300W omg lol" is still grossly exaggerated. It's a theoretical 10% THD power with the chip driven to maximum specification (52V 12A or something like that), and not possible with the device at hand and the available power supplies. Much like you, I wish they changed their advertising towards more honesty. "2x150W @ 4Ohm with 48V supply" is still impressive enough for my taste and a tiny amp this cheap, and wouldn't stop me from considering buying it at all.
@@ropeburn6684 I bought one of these little amps and I would not use it all of the way up, but all of the manufacturers lie in their specs. It's a fun phenomenon to watch. People gobble this stuff right up! "I got a gigawatt out of the amp using a single penlight cell!"
@@ropeburn6684 7A sustained, or just for a few milliseconds? I'm not complaining, but people who are agreeing with the comical claims from the manufacturers make themselves look slightly silly. While I did buy one of these things (a 2.1), it was about $40, so I don't feel badly if it sounds lousy. I don't expect much from it. It's only for travel use and it will be battery powered @ ~22V. anyway, this little industry is fun to watch. Lots of online people say that these cheap Class-D amps will take over the world and sound better than Macintoshes.
Where did you get your royalty-free source material? Thank you!
Odd that the mono isn't coupled because the chip can produce coupled.
I had a few ES components back in the day but never one of those baller CD players!
Merry Christmas
Love your stuff, can you include 6 ohm measurements in you vids ?
Hey man can you do a review on the MTX Terminator subs and amp?
Those last few seconds! That’s one of my favorite CDs of all time. Cool to know that you enjoy it as well! Cheers and Merry Christmas!
Hopefully I won't have to remove it as the track itself is public domain, but not sure about the Telarc recording. I had a lot of fun listing to a ton of CD's with this setup! Too bad the experience cannot be shared over RUclips
I recognize it but can’t remember that song. I think I used to own it.
Help a brother out?
@@effectivetactics422 it’s a Telarc recording. I’ll find a link and paste it in the comments.
Bachbusters, an awesome sound quality disc.
@@550n440THANK YOU! I think I STILL have that disc! You rock
That looks like a Nice desktop solution. This looks like the type of thing that will be good for somebody that's going to college and living in an apartment or a dorm.
Biggest cons is : No volume bypass.
U missed it..
Sorry, just now subscribed 😮, happy new year.
Hi! Stupid question but how would you wire it in a setup with an additional central speaker? I really love my old NAD... It gives a LOT in terms of soundstage vs most amps I tried. Perhaps this mini amp could be interesting to add. (btw, what music did you use for the test?)
I have a few NEW 2000 ppl amps…precious power
Did you see any issues with the balances circuits? I saw somewhere or might be an inferior typr of balancing.
Why would I want "USB for hi res audio" ... on a POWER AMP ?? 😖
Since it's a rhetorical question, no need for me to respond 👈😝
@@wal Not being funny or negative, just a genuine question... why would you see absence of USB input a 'con' on this device? 🤔
What amplifier do you recommend for two bass 12 audio pipe 4 magnets?
In Pro audio, TRS is balanced, just like XLR. Audiophiles be trippin and are the craziest customers to have when doing audio repair. Like being able to think you can hear the difference between different coupling capacitors. As long as they are in spec and used within spec, you will never hear the difference.
Yep ... I amazes me how much of their "science" exists only in their own group. In the real world people don't fix things that aren't broken.
Have you paid for the amp ? Are you sending it back or keeping it ? we just need to know ...
I did not pay for the amp but this doesn’t matter as I have more amps than I need and my goal is to share the info for others and not to promote any amplifier brand
🤔 I can DIY this one for less then have the price. But another great review test sir thank you
Awesome, thanks for watching and commenting!
I've been waiting for your say on the amp. Just waiting for it to get back in stock.