My Stingray is my absolute FAVORITE amp/clean amp that I've ever heard! The EF86 tone circuit in that amp, is pure magic. Thank you for your wonderful amps, past, present, and the ones to come!
Have some black plate 12AX7 tubes (1957-58), many hours b4 I got them and still hold up for 1000s of hours and sound great in my HHScott 222D. Like your presentation.
Hey Doc, you never mention the 12AX7 is a DUAL triode tube. That would be important when you describe a Blackface preamp - you make it sound like you need two tubes.
That's right, a 12AX7 as more combined gain than an EF86 and lower output impedance, so 12AX7 can drive a circuit more easily. The only advantages of EF86 is low input capacitance and the unique carater that the screen grid voltage sag inparts on the tone. Anyway there is a lot of wrong and missing information on this video. Try puting a tonestack after an EF86, you will loose at least 15dB of gain, so your gain factor of 250 will be reduced to 44. Whereas the 12AX7 will be less loaded, and there is still another one in the same tube to add more gain.
Thank you. I’d never heard of the EF86 tube before. After this, I’ll definitely be on the lookout for any amps that use them. Very curious to hear what they sound like in person.
6EJ7 also works great .( Sharp cutoff pentode) . Commonly used in TVs and can be found at low cost . I built a custom tube amp and used one in the first stage and had excellent sound quality.
Interesting 🤔. That's an octal base isn't it? I got a lot of weird tubes, by weird I mean not common to guitar amps, but I've always wanted to do some circuits around some of them. I think I might have some of those in my tube horde
A little late to the game, but thank you for posting this! EF86 is quite a marvel. I always think of Vox with the EF86 and how unique they sound. I’m sure that is in some way helped by the EF86 in the preamp circuit.
Yes your right the EF86 is a big part of that sound being the first stage which is where alot of the tone of any amp comes from. I'll tell what I did. I got one of ao-35 Hammond organ reverb amps of ebay paid 100 bucks for it about ten years ago. I don't know if you can still get them and if so what they would cost. But if you're lucky enough to find one grab it! That thing is already about 3/4 of the way to being a VOX AC-15. You got the tubes (el84s) and the transformers which are the biggest cost when building an amp from scratch. I grafted on an EF86 preamp with a rotary selector switch that selects a different capacitor in each position, its basically a course tone control. Then I have a volume and a cut control. It's a little bit cramped work in a small chassis but all the schematics can be found online and not many changes are required. Oh and btw it is absolutely killer! Not much headroom but the most beautiful overdrive ever! It makes about 15 watts so you can crank it to get that crunch without being evicted or arrested which is also good👍
@@lauratanner8475 That’s awesome. I found the right iron for the PT/OT from Hawk electronics, gutted my Vox AC-15 C1TV, drilled out a new chassis, threw in a rotary switch for tone selection, and voila! Very cool sounding circuit. Take care!
I have had 12at7 amp it was capable of plenty of gain for blues to classic rock it was a "thick" sounding amp that took a boost well but broke down alot
When you are in prototyping and tinkering on a new design, do you ever intercept the signal at intermediate stages to listen to it? I have been really curious about when statements like "this tube sounds very sweet", etc. because it seems like it would be difficult to isolate a single tube's effect on tone.
Amps are a sum of the parts, so a tube that sounds great in one amp can sound totally different in another. We test with the tube in the full circuit to determine what we prefer.
Thx Doc, interesting and informative as ever. I have some matched EL844s coming, gonna give em a shot in my early Maz 18 NR head. I recall you were a bit nonplussed?
I have a Premire that has a EF86 and the amp screams however it dose get Harmonic.Now I am wondering if a your saying you can just swap out the 12ax7 with a EF86. Thank you for the information on this beautiful sounding tube. c];-)
I have both 60th Ann Vox AC30 and AC15... I love them both dearly, but the Ef86 is certainly a special sound. However... when I crank the AC15, those EF86s are noisy/microphonic. Do you have any tips to curb that? Edit: I asked this question mid video, but I see now watching until the end, perhaps wing Cs might do the trick.
I have the 60th anniversary ac15 it's a wonderful amp I put a brimer meshplate ef86 in mine my point being changing that jj ef806 to a better valve is a significant upgrade Cheers
Dr Z. I wanted to ask your stance on the COVID vaccines? Ok I realize now I'm in the wrong place 😕 strangely enough this was just about the same amount of info I've gotten anywhere else on that matter. I also want to build an EF86 based preamp for some reason 🤔
I know the name might be confusing, but talk to your qualified healthcare provider on decisions related to your health. Our qualifications are only in rock and sometimes roll.
I'm aiming to get a Dr.Z amp but since I don't have a place to try them here in Toronto I was wondering what low watt amp with an ef86 60's vox influenced if u will or with thick midrange? If I could get an idea. Cause I think I need another amp to replace my badcat witch has been giving me a lot of problems lately. Thank you.
Hi SIlvio, we don't currently sell new EF86 amps. Also most of our EF86 amps are on the cleaner end of the spectrum. The VOX stuff tends to be dirtier. The lower watt amps that we in our line up were the M12 and Z28.
#drzama Have you ever considered doing a cheaper solid-state amp that would be more affordable to the public but still serve Dr. Z quality? Thanks, Cooper Kerby
Still Supro I personally own a tube amp and I love it, however, solid state amps have recently proved their worth, with amps like the Kemper Profiling amp and the Boss Katana series. Besides, I think it would be really cool to have a boutique amp company develop a solid state amp... We've seen VOX build solid state versions of the AC-30 and AC-15, so what if there was a solid state Maz-18 or a solid state Z-Wreck? For certain, nothing beats the sound and warmth of tubes, but solid state technology is quickly advancing, and I think having a lighter and cheaper option available would do pretty well in the amp industry.
Buzz Crumhunger it can be fine if the signal is balanced in the subsequent gain stages. Also remember in a typical cathode follower (say like a Marshall), you will have flipped the phase from the previous stages, there by allowing both sides of the waveform potential for clipping. It's all about balancing in the circuit.
What the?.. I don't get it,... Whats the point in a comparison /shootout..If you can't go "OK I like the EF86 sound... Think ill use those''...when you actually can't😒
@@derpdorf7054 He was simply answering a question about why he uses them in designs and what he likes about him. This is about his choice in designing around them, not our choice in using them
My Stingray is my absolute FAVORITE amp/clean amp that I've ever heard! The EF86 tone circuit in that amp, is pure magic. Thank you for your wonderful amps, past, present, and the ones to come!
Totally agree. My Stingray is a fantastic amp. Can't wait to hear more about the re-release of that amp.
One of my favorite AMAs yet. Great info Doc!
thank you I learn from every show you do
Think i'm going to buy a carol ann amp but i could listen to this guy all the day, such a nice person.
Have some black plate 12AX7 tubes (1957-58), many hours b4 I got them and still hold up for 1000s of hours and sound great in my HHScott 222D. Like your presentation.
I love my Dr Z Z-28-amp head. With the ef86 V1 tube, effects pedals literally become part of the preamp. A very nice sounding amplifier. Cheers!
they are our favorite preamp tube!
Hey Doc, you never mention the 12AX7 is a DUAL triode tube. That would be important when you describe a Blackface preamp - you make it sound like you need two tubes.
That's right, a 12AX7 as more combined gain than an EF86 and lower output impedance, so 12AX7 can drive a circuit more easily. The only advantages of EF86 is low input capacitance and the unique carater that the screen grid voltage sag inparts on the tone. Anyway there is a lot of wrong and missing information on this video. Try puting a tonestack after an EF86, you will loose at least 15dB of gain, so your gain factor of 250 will be reduced to 44. Whereas the 12AX7 will be less loaded, and there is still another one in the same tube to add more gain.
what a great explainer/teacher! of how the different tubes function
Thank you. I’d never heard of the EF86 tube before. After this, I’ll definitely be on the lookout for any amps that use them. Very curious to hear what they sound like in person.
Vox AC 30
Thanx doc... always appreciate your snippets. cheers
My 65 amps London Pro has an EF86 in the preamp section. Along with 2 12 AX7s. Easily the best British based amplifier I own! It has chime for days...
6EJ7 also works great .( Sharp cutoff pentode) . Commonly used in TVs and can be found at low cost . I built a custom tube amp and used one in the first stage and had excellent sound quality.
Interesting 🤔. That's an octal base isn't it? I got a lot of weird tubes, by weird I mean not common to guitar amps, but I've always wanted to do some circuits around some of them. I think I might have some of those in my tube horde
@@lauratanner8475 9 pin miniature .
Another great one. Thanks again for your knowledge!
Watched again!
Thanks Doc but its hard to concentrate on ef86 when the z80 is in the frame when will demos be available?
I'll save you from searching: Dr Z says no you can't replace your 12ax7 with an EF86. You're welcome.
This series mad me start shopping around for your amps more affordable on the used market I was watching for a carr Lincoln I may change my mind
Great info. Considering an amp with the ef86 and was not familiar. Thanks!
it's a spectacular tube
All the Grundig & Ferrograph Valve Reel to Reel tape recorder; the main preamp valve was the Pentode Valve was the EF86.
The demo circuit shown on the EF86 data sheet was widely used in consumer equipment.
A little late to the game, but thank you for posting this! EF86 is quite a marvel. I always think of Vox with the EF86 and how unique they sound. I’m sure that is in some way helped by the EF86 in the preamp circuit.
Yes your right the EF86 is a big part of that sound being the first stage which is where alot of the tone of any amp comes from. I'll tell what I did. I got one of ao-35 Hammond organ reverb amps of ebay paid 100 bucks for it about ten years ago. I don't know if you can still get them and if so what they would cost. But if you're lucky enough to find one grab it! That thing is already about 3/4 of the way to being a VOX AC-15. You got the tubes (el84s) and the transformers which are the biggest cost when building an amp from scratch. I grafted on an EF86 preamp with a rotary selector switch that selects a different capacitor in each position, its basically a course tone control. Then I have a volume and a cut control. It's a little bit cramped work in a small chassis but all the schematics can be found online and not many changes are required. Oh and btw it is absolutely killer! Not much headroom but the most beautiful overdrive ever! It makes about 15 watts so you can crank it to get that crunch without being evicted or arrested which is also good👍
@@lauratanner8475 That’s awesome. I found the right iron for the PT/OT from Hawk electronics, gutted my Vox AC-15 C1TV, drilled out a new chassis, threw in a rotary switch for tone selection, and voila! Very cool sounding circuit. Take care!
I have had 12at7 amp it was capable of plenty of gain for blues to classic rock it was a "thick" sounding amp that took a boost well but broke down alot
That really helped make sense. I get asked a lot about my Z28 and that helps me explain it. These series are really cool. What about EL’s vs 6L’s?
Great presentation...thanks. I used to own a Rt. 66, but sold it and bought a MAZ-18 NR head.
I had a Maz38Sr and what an amp but was way too loud Should have held on to it Using a 61 Princeton and Valco stuff
When you are in prototyping and tinkering on a new design, do you ever intercept the signal at intermediate stages to listen to it? I have been really curious about when statements like "this tube sounds very sweet", etc. because it seems like it would be difficult to isolate a single tube's effect on tone.
Amps are a sum of the parts, so a tube that sounds great in one amp can sound totally different in another. We test with the tube in the full circuit to determine what we prefer.
desde Mexico un saludo Dr Z me ha sacado de una duda que tenia
Thx Doc, interesting and informative as ever. I have some matched EL844s coming, gonna give em a shot in my early Maz 18 NR head. I recall you were a bit nonplussed?
I have a Premire that has a EF86 and the amp screams however it dose get Harmonic.Now I am wondering if a your saying you can just swap out the 12ax7 with a EF86. Thank you for the information on this beautiful sounding tube. c];-)
No, absolutely not, it will not take a 12AX7 as a replacement, and it can damage your amp!
@@DrZAmplification Thank you 👍
Anyone notice how Dr Z is no longer selling amps with ef86 tubes? Check their site
I have both 60th Ann Vox AC30 and AC15... I love them both dearly, but the Ef86 is certainly a special sound. However... when I crank the AC15, those EF86s are noisy/microphonic. Do you have any tips to curb that?
Edit: I asked this question mid video, but I see now watching until the end, perhaps wing Cs might do the trick.
I have the 60th anniversary ac15 it's a wonderful amp I put a brimer meshplate ef86 in mine my point being changing that jj ef806 to a better valve is a significant upgrade
Cheers
@@gregoryirwin263 Thanks!
@@joeschlicht no worries man happy tone hunting 👍
Is Eric Barbour the guy from metasonix?
Thank you doctor Z
Dr Z. I wanted to ask your stance on the COVID vaccines?
Ok I realize now I'm in the wrong place 😕 strangely enough this was just about the same amount of info I've gotten anywhere else on that matter. I also want to build an EF86 based preamp for some reason 🤔
I know the name might be confusing, but talk to your qualified healthcare provider on decisions related to your health. Our qualifications are only in rock and sometimes roll.
Would it be possible to have a Z-Plus style circuit with EF86's in it?
Not exactly.... buy you could make a parallel singled ended output section with an EF86 preamp.
I thought I was done getting amps Now I have too get one that benefits from this tube.
Can I unbalance the phase inverter with a 12 wd7 to get more positive harmonics?
No
I'm aiming to get a Dr.Z amp but since I don't have a place to try them here in Toronto I was wondering what low watt amp with an ef86 60's vox influenced if u will or with thick midrange? If I could get an idea. Cause I think I need another amp to replace my badcat witch has been giving me a lot of problems lately. Thank you.
Hi SIlvio, we don't currently sell new EF86 amps. Also most of our EF86 amps are on the cleaner end of the spectrum. The VOX stuff tends to be dirtier. The lower watt amps that we in our line up were the M12 and Z28.
How come no ef86 amps is current Z lineup anymore?
not much demand
@@DrZAmplification demand drives production totally get it. But IMO ppl are cray. The EF86 is a very special thing.
Hey Doc, I have a question: Can I replace a EF86 with a 12ax7 in a tube mic preamp? Or it won't be a good idea? thx
No, it does not have the same pin out. 9 pins vs 8 pins.
@@DrZAmplification Both the 12AX7 (ECC83) and the EF86 have a 9-pin base, but each tube requires different circuitry to operate.
My wife always tells me to focus the spray on my hose for more accuracy. Maybe need a ef86 🥴🥴
#drzama Have you ever considered doing a cheaper solid-state amp that would be more affordable to the public but still serve Dr. Z quality? Thanks, Cooper Kerby
Cooper Kerby
No solid state crap
Buy a tube amp big boy
Still Supro I personally own a tube amp and I love it, however, solid state amps have recently proved their worth, with amps like the Kemper Profiling amp and the Boss Katana series. Besides, I think it would be really cool to have a boutique amp company develop a solid state amp... We've seen VOX build solid state versions of the AC-30 and AC-15, so what if there was a solid state Maz-18 or a solid state Z-Wreck? For certain, nothing beats the sound and warmth of tubes, but solid state technology is quickly advancing, and I think having a lighter and cheaper option available would do pretty well in the amp industry.
I thought the asymmetric clipping was a good thing? Like in a cathode-follower driven tone stack?
Buzz Crumhunger it can be fine if the signal is balanced in the subsequent gain stages. Also remember in a typical cathode follower (say like a Marshall), you will have flipped the phase from the previous stages, there by allowing both sides of the waveform potential for clipping. It's all about balancing in the circuit.
Dr Z Amplification cool, thanks!
Can an ef86 replace v1 in a modern vox ac15c1 ?
no it can not. 9 pin vs 8 pin socket.
Dr. Z
Can we use EF86 instead of 12AX7
No, the tube socket wiring is different and you can short the amp if you try to substitute.
What the?.. I don't get it,... Whats the point in a comparison /shootout..If you can't go "OK I like the EF86 sound... Think ill use those''...when you actually can't😒
@@derpdorf7054 He was simply answering a question about why he uses them in designs and what he likes about him. This is about his choice in designing around them, not our choice in using them
I enjoyed this, I thought Telefunken EF86 tubes were the absolute best !!
The best EF 86s are the ones that aren't microphonic ;-)
What's that Z 80 ? Doc
it's the amp he's been teasing us with since before Christmas grr