I have bought today leak 30 plus in perfect conditions all original. Sound....? Wonderful. Very very pleasant sound. It is incredible how a so old amplifier sounds...I have a CA851a but the pleasure that comes from Leak is really different. Inside all components are in a particular order that confirm the good project. There are no noise or buzz or hiss...I love it! It is connected to a Jbl 4301b. Listening Jazz is pure melody. The bass are present with deep sound and body but are not intrusive, they are really balanced. Voices are present and the treble are not so metallic like modern amplifier. It is a masterpiece.
The Leak 70 was the second best amp you could buy in 1970 - at least in the UK (cost £56 without the wood case - £59 with it) I know coz I bought one from AT Labs in Enfield. Long gone now. Best amp was the Quad which was around £90. Most hifi mags of the time classed the Quad the best amp with the the Leak 70 a close second.
Great vid-thanks for sharing. Nice to see one of my favourite units getting some attention. I agree with another comment though that this particular amp might benefit from a service-especially as it was playing up when you first turned it on. I love my Leak Stereo 30 Plus, which sounds fantastic now I’ve replaced all its electrolytic capacitors-lots of clarity and detail, but it was playing up when I first got it.
I love this amp but, you need to recap it. This amplifier can be made to sing. The quiescent current needs setting. It is colourful and involving. Yours needs servicing. You can run it flat out and it doesn’t lose shape yours needs recapping by the sound of your description. I bought one from a secondhand shop when I was a student. I rebuilt it over one summer and it blew people’s minds. It impressed people running Hi Fi shops. It humbled lots of well respected equipment. Get yours serviced and most of your reservations will evaporate.
I was thinking the same thing. I have one and there's no hum (in fact the background is quieter than some modern amps) and it goes plenty loud without losing coherence. Also, the "missing centre", what? It says everything that he needed to leave it switched on for half an hour before it worked properly. I sure as hell don't have to do that with mine! I switch it on, it works. Yeah, this review made me think that amp's poorly and not representative of it's type and it was therefore an unfair review.
@Matthew Taylor Always fancied some of those but nowadays the trick is finding some that don't cost silly money. That and they're not what you'd call common. I'm intrigued by them though...
John sweda I think it was 1250microfarads per channel however, if you divide that between say eight or ten smaller capacitors in parallel. The bandwidth and power delivery improves and becomes more nimble. The boards are really easy to work on. This amp never cracks up even with full volume. It has lots of headroom. I took mine to a hi fi shop to audition speakers and everyone ended up in the room to listen. The one reviewed here needed recapping.
Because of this review I bought a Delta 70, sounded great till a channel stopped working- was a loose resistor. Checked smoothing and output capacitors and they were shot, replaced all 4 for a tenner and wow! As detailed as my Cambridge Audio CXA80, but much fuller and punchier bass. Liked it so much, I bought another Delta, replaced same caps again, same great sound, got a matching tuner too with the first one. Some of these amps have the speaker outputs wired backwards - my second amp has this prob, I just swap the speaker leads around. Love these amps! Thanks to Kelvin for getting me interested in this old gear.
@@stereoreviewx I can understand why these amps were regarded as giant killers in their day - pair them with decent speakers and a quality record deck and you would be very happy indeed!
The Stereo 70 is easy to work on; there are 2 identical preamp cards which you can unplug from the motherboard and switch. Easy to tell whether your problem is a preamp card, and which one it is. I think there are also 2 power amp cards (minus the final transistors), so you can do the same thing. If you have any electronics experience and can buy two "parts only" models cheaply, (and you replace the caps), you'll get a beautiful example of a Stereo 70.
Good review. My very first amplifier and intro into the hifi world was a Leak Stereo 30+. Great amplifier and provided me with a good grounding for later purchases to fuel an ongoing audio addiction.
I've just bought one for 90 euros based on this review....taking it to the tech as soon as it arrives for recapping and a service.....really looking forward to putting it in use with a Dual 1019 turntable and modern Q Acoustics 3050 floorstanders.....open to speaker suggestions from anyone....very much enjoy the channel and greetings from the Rock of Gibraltar.....
@@stereoreviewx thanks yes I will report exactly what the tech does to it and what it sounds like...and thanks for doing this review.....he was saying recapping from the off even before seeing it......bought it from a guy in Madrid
@@stereoreviewx finally got the Leak Stereo 70 from Madrid and took it straight to the tech in La Linea the town across the border from Gibraltar. We opened her up and he was loving it.....Nice and clean inside.....he was gushing....we are just going to change the two Potentiometers he said.....as the volume and balance were not as supposed to be......we're not gonna touch anything else as this is fantastic he said.....assembled by hand.....no robots used here......look he said.....gain switches on the back.....marvellous....hahaha he was loving it and the guy works on vintage amps 90 per cent of the time......powered up no problem and sounded great as is on even crappy speakers.....I have a question though......what speakers would you say this would be great with.....I have modern Q Acoustics 3050 floorstanders rated at 6 ohms and wondering whether they sure going to tax the amp too much?
Have been listening to the Leak Stereo 70 amp I bought for 2 days now. Have been running off a Rega and Dual turntable in turns connected to Q Acoustics 3050 floorstanders and QED cables. Two main albums I tested repeatedly: Van Morrison 'Keep on Singing' and Norah Jones 'Day Breaks' and to a lesser extent Bowie Zigggy Stardust and Miles Davis and John Coltrane albums. In summary I love this amp!!!!!! it's loud....certainly doesn't need the loudness button as you say.....esp connecting my Marantz tape deck and listening to The Doors LA Woman on that. Unlike yourself I like my bass and treble knobs and I find the bass powerful and the treble very different to my Marantz PM6006 modern amp.....it's a great amp for vocals that's for sure. It has a special way with treble, it goes further than modern amps. I didn't see the problem you found with stereo imaging as for example with the Norah Jones it placed the voice right in the middle. I found moving my listening position a bit helped move the stuff happening in the middle strangely enough. I find this amp detailed and it's like having a live concert in the living room. The 35w per channel are more than enough for me and I have enjoyed pumping out the music. I would recommend this amp for people who enjoy singers that's for sure. In summary I'm really happy I came across ur review as I went out and got one cos of it and I have retired the modem Marantz amp I have in favour of this that's from when I was born! I was born in 66 so theresbouts....
@@stereoreviewx thats the perfect way to describe it....it punches and I love it! Thanks for a great channel and great reviews and for putting this leak in my home!
I had never listened this Leak amplifier, in fact any Leak amplifier, but your vivid presentation reminded me of a receiver I had, B&O Beomaster 900 M, made during the second part of the 60s, with germanium transistors. What get your attention, almost immediately, when you listen Beomaster 900 M is the amount of bass you get. It’s just too much, not very focused, a bit loosen, but somehow, still pleasant - meaty, fatty bass. It felt like the loudness was always on, but only on bass, not on high frequencies, which were rather shy. The overall sound was clearly not hi-fi, especially in terms of resolution and you could feel, even on moderate volume, that there were some distortions. I wouldn’t dare to recommend this receiver to anyone, but it has his charm. Obviously, it needs very sensitive, easy to drive speakers - you know, old paper cone drivers. Thank you for sharing and keep up your good spirit!
It's possible a permanent loudness capacitor was installed across the volume pot, I get a lot of small amplifiers, suitcase record players and console grams that have that bullshit on them, I get in there and de-loudness them, much improved sound and no midrange honk when vol knob goes past 6
Great advice Kelvin regarding letting long sat gear power up for a considerable time before expecting too much of these old girls....let's show them some timely respect & our patience may well be rewarded... just say'in... :)
Great video Kelvin, as always......I was on a mid 2000's Denon PM720ish thing this weekend....really nice sound for a modern thing.....Clear and powerful! I'd like to check one of these Leaks.
Had a couple of Leak Delta 70s , very powerful and clear , not the muddiness of modern amps , just somewhat tizzyness in the treble , problem in the main was overheating.
The muddiness of which modern amps are you talking about? If anything, modern amps are clearer, more detailed, balanced and well defined across the frequency range, than many old vintage amps. PS. I am talking about good quality amps and not cheap rubbish amps.
I own kenwood ka 4002 and its from 1970 . Its really diffrent sound as well. Very interesting in presentation. Sound is liquid ( valvey) warm and charming, bass is huge and middel smooth and lovely. I don't have much experience but sound is very different to nad 3020 , pioneerA-400 or my new Technics Su g700 mk2. I love it and I may keep it for a long time . Maybe even recup found the future . Amazing power for 18w amp
Great channel Kelvin . I originally had a Rodgers HG88 mk11 back in early 70s Fancied a transistor amp . Really bad move ! Had several until I found a second hand Leak Stereo 70 . Loved it Being in the trade I've had so much gear Including valve amps . also still have a Mission Cyrus which is pretty good I've got a Sonneteer class D amp which is definitely a keeper but both of your two amps are very different and enjoyable
There are two plug in boards for the preamp, and two for the driver stages, the contacts on these sometimes need cleaning. Improved sound can be obtained by feeding into the tape input, missing out preamp stages and the tone controls.
@@stereoreviewx It should be a noticeable improvement going into the tape input, this also applies to the Stereo 30 plus and (I think) to the Stereo 30. I still own all of these amps and the matching Sterofetic FM tuner.
@@Radfordperson I have the 30 plus and just compared it again to other amps I own. The mids and highs are what I would describe as clean and detailed and the bass tight but light which is different to Kelvin's experience. Overall preferred to low powered early Marantz, Sansui who bass despite being more dominant can be a loose/woolly. Now interested in hearing a 70. With added bass sounds like a perfect amp. Agree it losses its shape when volume is turned up.
I have a Stereo 70 and some Ditton 15xr's too, I have a Lenco Goldring GL75 turntable instead though. Has a great sound, my 70's records sound great on it.
My dad had one of these when I was a kid and i inherited it for a couple of years when I went to Uni. Very pleasant easy going sound with smooth highs and natural tone. Not the last word in detail or dynamics but nothing sounded bad on it. Was very disappointed when I bought my first Kenwood amp (at 80 Watts a channel) by how bright and fussy the sound was by comparison.
Nice one Kelvin, I asked you for your opinion on the kef cresta 2 the other week and thanks for the reply, I wired them up but wasn't overly impressed, very loud but every song I played I had to adjust the bass & treble constantly trying to get them to sound good, gone back to my TDL monitors which are smaller but more responsive and much better sound quality, to my ears anyway....
Hi, I think you should compare the 70 to the only solid state leak amplifier you really need, the stereo 30 (no, not the plus) if you have high efficient speakers. By the way what you say about the time it needs to start after a long time of not using it it's really strange. When something stays on a shelf for more than 5 years you really should start it using a variac and consider a change of all the electros or at least the ones that measure out of specs. If everything is ok and after the right idle current and offset tuning you are ready to go after the first two or three minutes of warming up. Never lit up something after more than 5 years of sleeping without a variac. I've seen so many amps in smoke in the last 30 years of activity ...
I really like what you do here. It's good to know there are others who are as crazy about vintage audio as myself. I have the Sansui QR 500, I'd like to know what you think about it and other quadrophonic systems as well.
I have a Leak Stereo 70 stashed in the attic which was working perfectly when I put it into storage 20 years ago. Inside it has a "motherboard" with four daughterboards plugged into it. This makes it easy to repair (have done it). Well within the skill set of an audio electronics amateur who knows how to use a multimeter and an oscilloscope. By modern HiFi standards I would rate it as a "party amp". Still OK if you're a student on a budget. When it comes to retro HiFi, there are some great speakers out there, great decks and great valve amps (if you can get someone to replace all the capacitors) but early transistor amps like the Leak show their age more than any other component. As ever with HiFi, your mileage may vary. 😀
I picked this amp up in the early 90’s and is a really good amp. Sound is very realistic. Very good amp if you can get cheap and with the appropriate speaker plugs. I also had the Delta 30 and is good. Is that a Cyrus 2? If it is fantastic. Cyrus 2, Stereo 70 and Delta 30 in that order.
Had mine partnered with a pair of Heybrook HB1 (green outline) and sounded amazing. On a good day the Stereo 70 sounded out if this world. Unfortunately it was sensitive to dirty mains and spikes and would make random popping and electrical noises. As you mentioned it extracted a lot of detail out of the source, but it wasnt very clean. If you had a hissy tape you would hear a lot of hiss. In contrast the Cyrus 2 was very clean and stable for its day. I use to run it through a pair of Monitor Audio mid floor standers. Cant remember the model but they were deep and came with small stands. That sound was very authoritative with great scale.and timing. Great memories thank you.
You can get the speaker output plugs changed for modern binding posts by your friendly local engineer but I appreciate this lowers value as it makes them non standard but is beter really. I may do this with mine.
Imo the stereo 30 was the best leak transistor amp and the best sounding was the first gen with germanium transistors and that was according to my 20yr old daughter who actually had full hearing capabilities. But both types were really good with early Kef Celeste’s anyway.
I'm considering it in combo with a pair of old Goodmans G Mezzo 3's. I use them with a Pioneer SA - 408 now. They have an excellent space but the upper mid range is a bit too much and th every high's are not very pronounced. Do you recommend to switch, or with this amp the upper mid range will be even more strong? Thanks!
I picked a leak stereo 70 up the other week for £20 iv dropped it off at a repair shop to be checked out before i try it out, hopefully not a lot wrong with it, i really wont to try it out and like it id love one of them mission Cyrus amps vintage amps and speakers have got me i can ot stop looking at them, i love your videos they are great
I think im going to go for it on the repair and recap of my leak 70 and get all of the plug ins changed in the back so i can just plug everything into it RCA and banana Plugs for my speaker's i love your video on the spender bc1 im listening to mine as i type im running my quad 303/33 it all sounds fantastic to me you have got me wanting some Rogers LS3/5A now the misses got me some kef cadenza speakers for my birthday i love ber lol great speakers do a video on the nad 3020 i think its a classic id love too known your thoughts up on them keep up your great videos they are great
If you're using a CD player with it you can't go full volume because it's over driving the pre amp. The CD line level out is well in excess of the max input sensitivity of the amp. Try some attenuated phono connectors or the sensitivity switch on the back. I have both the 30 plus and the 70. I need to get around sorting the 70. The best thing to do with them is gut them; remove and bin all the old capacitors, all of them, including the film caps. Bin all the now well drifted carbon composite resistors and pots, and bin the driver transistors. New uprated Panasonic FM FC, electrolytic caps throughout, new PSU reservoir and Decoupling caps, wima and vishay MKP, new metal film resistors and I can't remember what driver transistors I fitted, new pots and finally some decent phono and speaker connectors. oh and new rectifier diodes, buse the uprated PSU Caps will destroy the old ones. Some might say "that's not how Harold Leak intended it as you're changing it all". Well, the ones with all original components in them are less like how he intended as they are all well out of spec even new old stock. The difference will be night and day and for me it was worth every penny beautiful lovely detail and calming. Listen if you want to relax at medium volume and hear the music. Oh and make sure you have a really good source. Not worth it if you can't rebuild it yourself.
Wow! I'd been wondering about Leaks. There are always quite a few for sale near me, and usually for little money. How do they sound in comparison to the Sugden you reviewed?
Matt. When I bought my FIRST CDP (AR CD04) in 1987 I pitted my then Leak 2200 (mid 70's) against a Dealers Sugden A48 (overhyped IMO) and the Leak was much better all round......punchier, sweeter, better bass. Was expecting the opposite to be honest.
Bought a Leak Stereo 30 Plus for 55 euros in Spain and had it serviced back to brilliance! Its the amp Jimi Hendrix had in his home in London that's now open as a museum with Lowther speakers and a Band and Olufson turntable plugged to it. You should get hold of one and see what you think....it's impressive!
Nope! He had a Stereo 30, not a PLUS! He and Barrett had the same amp. The only one with Germanium transistors. When you hear one you get hooked to that damn thing ... The Stereo 30 Plus is nothing but a simple integrated amp with average sound.
@@sirnosedavoidoffunk I stand corrected.....was only based on what I had read. Here's what HIFI NEWs say: "The Stereo 30 used germanium transistors because that was all that was available at the time. They worked but were noisy and prone to thermal runaway, making it a challenge to design practical hi-fi amplifier circuits using them. Nevertheless, the Stereo 30 was well regarded and sold successfully until the appearance of silicon transistors in the middle of the decade signalled a step change in amplifier performance. Quieter and more stable, silicon made it possible to build high-gain, high-power circuits with relative ease. The Stereo 30 Plus was essentially the original concept built around a complete lineup of silicon devices. It was the same, only better.
I'm very interested how do they sound in comparison to the Sansui AU101.? Both have a very similar electrical circuit. The difference is in the supply voltage of the Leak 74 Volt, Sansui 44 Volt. Leak has a larger output capacitor. Probably better bass. The rest is the same. The question is who copied whom.
Yeah I got the sensory 101 the difference is very big the leak is hugely bold and big in the base and the mid range Sansu is delicate fast light on its feet. K
This is the holy grail......classic Brit sound. Most would pass these days, I believe. There is a hipster 130 now, but only in name. Those terrible hipster diseases.....
I have a Leak Stereo 30 Plus (bought for 55 euros, needed service) and a Stereo 70 - bought for 90 euros (needed service) and Leak Mini Sandwich speakers (have put in a new crossover)
@@cameronkrause4712 the stereo 70 uses silicon transistors - like bc148, bc149, bc107 etc in the pre amp and some beefy 2n3055s among others in the output stage. The schematic is available on line. It’s quite a complicated design. As far as know the delta 70 and the stereo 70 are pretty much the same design, just a different chassis. EDIT. On further inspection, it’s not that complicated after all...
Much prefer your reviews to the modern magazine Reviewers BS such as brightly lit, macro dynamics, micro detail ?? etc. and other words we DO NOT understand.
Thanks for that k. I did plug in headphones and it did work on both channels. Though still no sound from Left speaker. We used to smack the side of our old Grundig tv once in a while I remember as a kid and the thing would always come back to life until one of the valves would blow of course and we all knew a guy who knew a guy who doubled up as tv repair man in his spare time and would do the deed in the middle of our living room for peanuts... sorry I went off on a little tangent for a there... was referring to my sansui 331 above
Had to do an Elvis special with it - ‘return to sender’. .. but the sound out of myTannoy speaker has never sounded so warm and not leaving me ‘wanting’- even though it was one functioning channel out of the mighty 331...
@@stereoreviewx Sansui S-65 on e bay now... 12" woofer, 4" midrange, and a 3 inch tweeter. All tested working fine, apparently! I'm guessing these are not great as unable to find much positive vibes on line....Look beefy though...
When people came in and asked what an amplifier sounded like we would connect one up and let them listen. Reviewers that worked for Hi Fi Magazines would always argue that an amplifier should sound neutral. A straight wire with gain was coined as the perfect amplifier. Then makers went mad on eliminating all switches and tone controls from the signal path they were removed completely. Bare naked amp with a volume control.
Hi Kelvin, I've acquired an old Leak 2000 amplifier. It seems to switch on but that's as far as I've gone with it. Its in terrible cosmetic condition, do you have any experience of this model? I suppose my question is do you think its worth sorting out ?
They are quite easy to work on for the most part, the electrolytic caps are past their best and often a cause of problems. The push switches on the front/back generally need some contact cleaner, along with the volume/tone controls, they all carry signal at some point. If the lights don't come on when you power it up make sure the bulbs aren't loose, they have a habit of backing off. Once serviced, the Leak 2000 sounds very nice.
These kind of amps are really for vintage lovers only who want to feel like at the time these amps were built. They are comparatively cheap nowadays BUT it’s another thing if you really want to put something like that in your regular system - if you’re not a collector of that kind of stuff. On the other hand these amps (like all amps) also take space and collect dust. That at least for me is a reason to only have the amp I really want to listen to all of the time. But there certainly are different views/ approaches out there...
I own a Sony TA-2000F and TA 3200F fully revised and mint condition. They are made 1971 and they sound detailed, rich with a wide open stage, full spectrum. I also use a modern avrDenon X6400H, which sounds different, straight forward bass , less detailed, smaller stage. Not bad just different but i prefer the way the old Sony's reproduce music . I was surprised and impressed how good this old stuff sounds. A bit different is my experience with loudspeaker: You can get good loudspeakers made in the 70' s or 80' s ( like my KEF 103.2 reference or my Rogers Studio 1a) but it is much easier to find good loudspeaker made in the 90's as technical progress made it easier and also cheaper to produce good loudspeaker. I really enjoy watching your videos and looking forward to see more of them regards Oliver from Berlin / Germany
The reason it takes so long to get working is most likely capacitors reforming, I believe this is germanium Transistors first generation they were never the greatest. Still a very impressive amp for the time I have some Armstrong amps of a slightly later vintage I have restored a few of them might be worth a look.
Enjoyed watching this. I always thought these sounded pretty rough and Leak had at this time been bought out by the Rank organisation and nothing would be the same again..Compared with a Stereo 20 from the year before, blimey I always thought about people 'upgrading' to the latest Leak at the time. Must have been an awful disappointment. For people looking in re. ''old amp not working' there is a certainty the switches will require a clean. These Leaks have a whole bunch of switches between the source and amplifier actual. Cleaning these will solve 90% of problems and improve quality by same amount. The other thing is of course the state of the electrolytics. The silicon or germanium devices will either work or not and are mostly reliable.So if it is generally giving a clean output with no hum or noise, clean switches and pots.
I actually have a 2004 year model NAD amplifier and it is obviously solid state but I really think it sounds better after some heat builds up in it. I know that's counterintuitive but I'm positive it's so. It isn't a figment of my imagination. On a side note I've been wanting to pick myself up a Cyrus 2 but I just haven't found one I like yet. I prefer to buy from electronic techs that service and clean them and put at least some warranty on them.
It would stand a mild update. Baxendale diode to quasi output stage. 250 VA toroidal transformer.. Better quality but same size capacitors. Capacitors in general. Don't retain the transformer and fit big capacitors . MA4, yes please.
j ai cette ampli avec les sandwich 600 c est vraiment exceptionnel ,et je partage votre ressenti sur se leak stéréo 70 ,et je suis encore en hésitation entre lui et la série Kenwood l 1000 m-c-d qui est aussi exellente mais haut de gamme pour vous dire que cette ampli est vraiment surprenant
It doesn’t sound like the niad exactly which I have had it’s bigger and bolder . Both have great bass grip. The night is smoother bit more sophisticated and you can listen to the nad all day It’s less tiring I mean
sorry have to say,if on turn on amp is not good for that long?Then its probably going to be one that has never been maintained,capacitors,dont last that long,you could only A/B this amp,if it was re-capped all.And cleaned all pots and switches.
Capacitors might need to reform and push buttons will need contact cleaner then bombproof. Harold Leak always aimed for less than 0.1% distortion from his earliest post-war designs. Try pairing with original Leak Sandwich speakers which were decades ahead of their time using stiff cones and damped cabinets.
It cleans the dirt of the contacts and especially the pots (electronic parts of the volume controls). Better off buying and fitting new pots if you can find them and fit them.
Please don't take this the wrong way, but when I've seen your reviews they've been comprised solely of your talking about the product. You;re not alone in this, but when I click on a review I'm expecting to hear the product being demonstrated. Is this unrealistic in your view?
It's difficult to really provide an accurate picture of a leak st70 in any review unfortunately..nor of any piece of vintage kit that age. The reason is that with almost certainty the components internally will be miles out of spec...caps esiecially but even transistors of that age were notoriously unreliable. I have a similar Leak in my collection but wont fire it up until I can get around to servicing it. Once done they tend to sound better and there's less chance of any dc offset due to drift frying your speakers😉
This amplifier and the delta series that came later all used quasi complementary output stages and therefore produced odd harmonic distortion. This distortion produced a sibilant sound which was quite unpleasant.
@@jeffsimon9594 Yes I did back in the 1970's. I then moved on and designed dc servo power amplifiers with lateral power mosfet output stages. Vastly better sound quality compared to the old Leak amplifier. Harmonic distortion 0.01% and frequency response within 0.1dB from 2Hz to 60Khz. Output power 272W into 8 ohms and 450W into 4 ohms. Each channel has it's own 625VA toroidal power supply for dual monaural operation. I have two of these stereo power amplifiers driving my Tannoy's in bi-amplified mode. The result is stunning with astonishing detail and kick ass low distortion clean bass.
I have one of each of these amps. I prefer the Leak. I don't have to let it "warm up" for half an hour, it works perfectly straight away. There is no hum. What I'm saying is the amp you reviewed seems far from healthy and as such, this wasn't a fair review. After all, no one would take a car review seriously if the test car hadn't been run in years and had worn suspension and brakes and the engine needed a rebuild, it wouldn't be representative of it's type. The "missing centre image" isn't something I've experienced with mine, nor the inability to go loud. It becomes uncomfortably loud long before noticeable distortion sets in. What I do agree with is the "up front" sound characteristic, the mid does tend to be strong although this isn't to a problematical degree. It appears to be a characteristic of early solid state hi fi amps, my Rogers Ravensbourne is the same. As you said, careful speaker matching pays dividends when using devices such as these. The Cyrus. Technically it's a more "correct" sound, the amp melts into the background and adds no characteristics of it's own or at least to a much lesser extent than the likes of the Leak or the Rogers. It seems pretty much bomb-proof although it's worth bearing in mind the speaker output protection leaves a lot to be desired. Like the Leak and the Rogers, on the Cyrus the only output protection is a fuse for each channel. I'm given to understand sometimes the fuses aren't enough, they don't act quickly enough and the output stages can become cooked at very short order! I find the Cyrus less flexible than the other two amps, no mono switching, no tone controls, basically a power amp with input attenuation and a (very good) phono pre-amp. It's gutsy enough and involving to listen to but I just find the Leak more exciting to listen to, frequency imbalances and all! It's true that solid state hi fi was still in it's infancy in the late 60's, the basics were there but the execution still needed a bit of work. The state of the art would still be another 5 or more years in the future but at the same time I can't help thinking something may have been lost in the process...
Thanks for your comments very interesting regarding the leaks temperamental behaviour I’m just trying to warn innocent people that these amps are often not functioning good. Could you tell me your favourite and for any other insights about whT sounds good old or new cheers K
@@stereoreviewx Ok, 2 amps I regrettably no longer own: FAL Phase 44, 1969-73, 20 watts RMS per channel @ 8 ohms, same left/right mono switching arrangement as the Leak, amp sounds much more powerful than it is, doesn't have the typical midrange heavy early transistor sound but tending toward a warm sound. Trio KA4002A, 1972-75, 25 watts per channel RMS @ 8 ohms, physically slightly smaller than the Leak but has even better facilities, 2 aux inputs, 2 turntable inputs (although both same sensitivity) 1 tuner and 1 tape loop, pre-power inputs and outputs, not sure now if it had a mono output for subwoofer, very solidly built and sounded quick and modern. I severely regret parting with these amps! They both sounded awesome playing through Wharfedale Dovedale mk3 speakers. The Trio fed with an Ortofon VMS3 cartridge in a Pioneer PL-512 turntable sounded better than it had any right to! The PL-512 was a budget deck. They had an rrp of £49.95 in 1979 and were a development of the earlier PL-12-D which I also owned at the time. However, due to clever plinth design, gone was the PL-12-D motor rumble. The PL-512 was for the time a minimalist deck. Totally manual but powered by a mains synchronus motor, it at least featured a mechanical speed selector instead of having to mess about removing the platter and refitting the belt as with some later minimalist designs... I still own the 512 and although it's fair to say it's cosmetically challenged (I obtained it with burn marks in the lid and the plinth is grubby and wouldn't even clean up when I tried oven cleaner on it!) it's been absolutely reliable, never goes out of tune no matter how long it's left unused for and fitted with an Ortofon VMS 10E cartridge, is kind to records and gives suprisingly good, stable stereo imaging. I've got a house rammed full of this kind of stuff dating from about 1965 - 1990. My mates call me eccentric. They also call me when their stereo gear fails them because I have a soldering iron and a multimeter and know how to use them...
I have bought today leak 30 plus in perfect conditions all original. Sound....? Wonderful. Very very pleasant sound. It is incredible how a so old amplifier sounds...I have a CA851a but the pleasure that comes from Leak is really different. Inside all components are in a particular order that confirm the good project. There are no noise or buzz or hiss...I love it! It is connected to a Jbl 4301b. Listening Jazz is pure melody. The bass are present with deep sound and body but are not intrusive, they are really balanced. Voices are present and the treble are not so metallic like modern amplifier. It is a masterpiece.
Great the leak really gives you something unusual It’s exciting and alive
The Leak 70 was the second best amp you could buy in 1970 - at least in the UK (cost £56 without the wood case - £59 with it) I know coz I bought one from AT Labs in Enfield. Long gone now.
Best amp was the Quad which was around £90. Most hifi mags of the time classed the Quad the best amp with the the Leak 70 a close second.
Great vid-thanks for sharing. Nice to see one of my favourite units getting some attention. I agree with another comment though that this particular amp might benefit from a service-especially as it was playing up when you first turned it on. I love my Leak Stereo 30 Plus, which sounds fantastic now I’ve replaced all its electrolytic capacitors-lots of clarity and detail, but it was playing up when I first got it.
Yeah new to your channel and pretty addictive. Sensible reviews and well balanced pros and cons of old equipment. Well done mate keep em coming
Love the look & style of the Leak Stereo 70, a classic amplifier.
I love this amp but, you need to recap it. This amplifier can be made to sing. The quiescent current needs setting. It is colourful and involving. Yours needs servicing. You can run it flat out and it doesn’t lose shape yours needs recapping by the sound of your description.
I bought one from a secondhand shop when I was a student. I rebuilt it over one summer and it blew people’s minds. It impressed people running Hi Fi shops. It humbled lots of well respected equipment. Get yours serviced and most of your reservations will evaporate.
What was the capacitance of the filter caps did you increase it
I was thinking the same thing. I have one and there's no hum (in fact the background is quieter than some modern amps) and it goes plenty loud without losing coherence. Also, the "missing centre", what?
It says everything that he needed to leave it switched on for half an hour before it worked properly. I sure as hell don't have to do that with mine! I switch it on, it works.
Yeah, this review made me think that amp's poorly and not representative of it's type and it was therefore an unfair review.
@Matthew Taylor Always fancied some of those but nowadays the trick is finding some that don't cost silly money. That and they're not what you'd call common. I'm intrigued by them though...
John sweda I think it was 1250microfarads per channel however, if you divide that between say eight or ten smaller capacitors in parallel. The bandwidth and power delivery improves and becomes more nimble. The boards are really easy to work on. This amp never cracks up even with full volume. It has lots of headroom. I took mine to a hi fi shop to audition speakers and everyone ended up in the room to listen. The one reviewed here needed recapping.
@@christopherward5065 sounds about right what a brand and type of capacitor did you use you didn't swap out any of the resistors or transistors
Because of this review I bought a Delta 70, sounded great till a channel stopped working- was a loose resistor. Checked smoothing and output capacitors and they were shot, replaced all 4 for a tenner and wow! As detailed as my Cambridge Audio CXA80, but much fuller and punchier bass. Liked it so much, I bought another Delta, replaced same caps again, same great sound, got a matching tuner too with the first one. Some of these amps have the speaker outputs wired backwards - my second amp has this prob, I just swap the speaker leads around. Love these amps! Thanks to Kelvin for getting me interested in this old gear.
Yes they are kick arse amps
Literally that bass will be kicking you around the room
Glad you liked it cheers
@@stereoreviewx I can understand why these amps were regarded as giant killers in their day - pair them with decent speakers and a quality record deck and you would be very happy indeed!
The Stereo 70 is easy to work on; there are 2 identical preamp cards which you can unplug from the motherboard and switch. Easy to tell whether your problem is a preamp card, and which one it is. I think there are also 2 power amp cards (minus the final transistors), so you can do the same thing. If you have any electronics experience and can buy two "parts only" models cheaply, (and you replace the caps), you'll get a beautiful example of a Stereo 70.
Good review. My very first amplifier and intro into the hifi world was a Leak Stereo 30+. Great amplifier and provided me with a good grounding for later purchases to fuel an ongoing audio addiction.
Just bought a Leak 70 and a Leak FM Stereofetic receiver - both sound fantastic
I've just bought one for 90 euros based on this review....taking it to the tech as soon as it arrives for recapping and a service.....really looking forward to putting it in use with a Dual 1019 turntable and modern Q Acoustics 3050 floorstanders.....open to speaker suggestions from anyone....very much enjoy the channel and greetings from the Rock of Gibraltar.....
Hi Steven yeah let us know what you think of the sound it’s got huge tight bass
@@stereoreviewx thanks yes I will report exactly what the tech does to it and what it sounds like...and thanks for doing this review.....he was saying recapping from the off even before seeing it......bought it from a guy in Madrid
@@stereoreviewx finally got the Leak Stereo 70 from Madrid and took it straight to the tech in La Linea the town across the border from Gibraltar. We opened her up and he was loving it.....Nice and clean inside.....he was gushing....we are just going to change the two Potentiometers he said.....as the volume and balance were not as supposed to be......we're not gonna touch anything else as this is fantastic he said.....assembled by hand.....no robots used here......look he said.....gain switches on the back.....marvellous....hahaha he was loving it and the guy works on vintage amps 90 per cent of the time......powered up no problem and sounded great as is on even crappy speakers.....I have a question though......what speakers would you say this would be great with.....I have modern Q Acoustics 3050 floorstanders rated at 6 ohms and wondering whether they sure going to tax the amp too much?
Have been listening to the Leak Stereo 70 amp I bought for 2 days now. Have been running off a Rega and Dual turntable in turns connected to Q Acoustics 3050 floorstanders and QED cables. Two main albums I tested repeatedly: Van Morrison 'Keep on Singing' and Norah Jones 'Day Breaks' and to a lesser extent Bowie Zigggy Stardust and Miles Davis and John Coltrane albums. In summary I love this amp!!!!!! it's loud....certainly doesn't need the loudness button as you say.....esp connecting my Marantz tape deck and listening to The Doors LA Woman on that. Unlike yourself I like my bass and treble knobs and I find the bass powerful and the treble very different to my Marantz PM6006 modern amp.....it's a great amp for vocals that's for sure. It has a special way with treble, it goes further than modern amps. I didn't see the problem you found with stereo imaging as for example with the Norah Jones it placed the voice right in the middle. I found moving my listening position a bit helped move the stuff happening in the middle strangely enough. I find this amp detailed and it's like having a live concert in the living room. The 35w per channel are more than enough for me and I have enjoyed pumping out the music. I would recommend this amp for people who enjoy singers that's for sure. In summary I'm really happy I came across ur review as I went out and got one cos of it and I have retired the modem Marantz amp I have in favour of this that's from when I was born! I was born in 66 so theresbouts....
Hi there great to hear you’re enjoying that leak it is something else punchy as hell makes almost all modern amps seem gutless and lifeless cheers K
@@stereoreviewx thats the perfect way to describe it....it punches and I love it! Thanks for a great channel and great reviews and for putting this leak in my home!
The Leak amplifiers of that era used quasi-complementary output stages which produced odd harmonic distortion. This made them sound sibilant.
I had never listened this Leak amplifier, in fact any Leak amplifier, but your vivid presentation reminded me of a receiver I had, B&O Beomaster 900 M, made during the second part of the 60s, with germanium transistors.
What get your attention, almost immediately, when you listen Beomaster 900 M is the amount of bass you get. It’s just too much, not very focused, a bit loosen, but somehow, still pleasant - meaty, fatty bass. It felt like the loudness was always on, but only on bass, not on high frequencies, which were rather shy. The overall sound was clearly not hi-fi, especially in terms of resolution and you could feel, even on moderate volume, that there were some distortions. I wouldn’t dare to recommend this receiver to anyone, but it has his charm.
Obviously, it needs very sensitive, easy to drive speakers - you know, old paper cone drivers.
Thank you for sharing and keep up your good spirit!
It's possible a permanent loudness capacitor was installed across the volume pot, I get a lot of small amplifiers, suitcase record players and console grams that have that bullshit on them, I get in there and de-loudness them, much improved sound and no midrange honk when vol knob goes past 6
@@manFromPeterboroughgood info, thank you!
Great advice Kelvin regarding letting long sat gear power up for a considerable time before expecting too much of these old girls....let's show them some timely respect & our patience may well be rewarded... just say'in... :)
Great video Kelvin, as always......I was on a mid 2000's Denon PM720ish thing this weekend....really nice sound for a modern thing.....Clear and powerful! I'd like to check one of these Leaks.
Had a couple of Leak Delta 70s , very powerful and clear , not the muddiness of modern amps , just somewhat tizzyness in the treble , problem in the main was overheating.
The muddiness of which modern amps are you talking about? If anything, modern amps are clearer, more detailed, balanced and well defined across the frequency range, than many old vintage amps. PS. I am talking about good quality amps and not cheap rubbish amps.
I own kenwood ka 4002 and its from 1970 . Its really diffrent sound as well. Very interesting in presentation. Sound is liquid ( valvey) warm and charming, bass is huge and middel smooth and lovely. I don't have much experience but sound is very different to nad 3020 , pioneerA-400 or my new Technics Su g700 mk2. I love it and I may keep it for a long time . Maybe even recup found the future . Amazing power for 18w amp
Great channel Kelvin . I originally had a Rodgers HG88 mk11 back in early 70s
Fancied a transistor amp . Really bad move ! Had several until I found a second hand Leak Stereo 70 . Loved it
Being in the trade I've had so much gear
Including valve amps . also still have
a Mission Cyrus which is pretty good
I've got a Sonneteer class D amp which is definitely a keeper but both of your two amps are very different and enjoyable
There are two plug in boards for the preamp, and two for the driver stages, the contacts on these sometimes need cleaning. Improved sound can be obtained by feeding into the tape input, missing out preamp stages and the tone controls.
Will try that thanks K
@@stereoreviewx It should be a noticeable improvement going into the tape input, this also applies to the Stereo 30 plus and (I think) to the Stereo 30. I still own all of these amps and the matching Sterofetic FM tuner.
@@Radfordperson I have the 30 plus and just compared it again to other amps I own. The mids and highs are what I would describe as clean and detailed and the bass tight but light which is different to Kelvin's experience. Overall preferred to low powered early Marantz, Sansui who bass despite being more dominant can be a loose/woolly. Now interested in hearing a 70. With added bass sounds like a perfect amp. Agree it losses its shape when volume is turned up.
I picked up one of these recently. Playing vinyl with an LP12 and Celestion Ditton 15xr speakers is very enjoyable
I have a Stereo 70 and some Ditton 15xr's too, I have a Lenco Goldring GL75 turntable instead though. Has a great sound, my 70's records sound great on it.
My Dad had the big Leak 'Sandwich' speakers. Where is pride and joy :)
I felt sure you were going to make a joke out of sandwich and Mothers pride
My dad had one of these when I was a kid and i inherited it for a couple of years when I went to Uni. Very pleasant easy going sound with smooth highs and natural tone. Not the last word in detail or dynamics but nothing sounded bad on it. Was very disappointed when I bought my first Kenwood amp (at 80 Watts a channel) by how bright and fussy the sound was by comparison.
Nice one Kelvin, I asked you for your opinion on the kef cresta 2 the other week and thanks for the reply, I wired them up but wasn't overly impressed, very loud but every song I played I had to adjust the bass & treble constantly trying to get them to sound good, gone back to my TDL monitors which are smaller but more responsive and much better sound quality, to my ears anyway....
Hi, I think you should compare the 70 to the only solid state leak amplifier you really need, the stereo 30 (no, not the plus) if you have high efficient speakers. By the way what you say about the time it needs to start after a long time of not using it it's really strange. When something stays on a shelf for more than 5 years you really should start it using a variac and consider a change of all the electros or at least the ones that measure out of specs. If everything is ok and after the right idle current and offset tuning you are ready to go after the first two or three minutes of warming up. Never lit up something after more than 5 years of sleeping without a variac. I've seen so many amps in smoke in the last 30 years of activity ...
Long term storage is the worst thing you can do to any vintage hifi, but EVERYONE does it.."Oh yes I have one of those in the loft..." 🙄
I really like what you do here. It's good to know there are others who are as crazy about vintage audio as myself. I have the Sansui QR 500, I'd like to know what you think about it and other quadrophonic systems as well.
I have a Leak Stereo 70 stashed in the attic which was working perfectly when I put it into storage 20 years ago. Inside it has a "motherboard" with four daughterboards plugged into it. This makes it easy to repair (have done it). Well within the skill set of an audio electronics amateur who knows how to use a multimeter and an oscilloscope.
By modern HiFi standards I would rate it as a "party amp". Still OK if you're a student on a budget. When it comes to retro HiFi, there are some great speakers out there, great decks and great valve amps (if you can get someone to replace all the capacitors) but early transistor amps like the Leak show their age more than any other component. As ever with HiFi, your mileage may vary. 😀
"I put it into storage 20 years ago", ah, there was your first mistake.
I picked this amp up in the early 90’s and is a really good amp. Sound is very realistic. Very good amp if you can get cheap and with the appropriate speaker plugs. I also had the Delta 30 and is good. Is that a Cyrus 2? If it is fantastic. Cyrus 2, Stereo 70 and Delta 30 in that order.
Had mine partnered with a pair of Heybrook HB1 (green outline) and sounded amazing. On a good day the Stereo 70 sounded out if this world. Unfortunately it was sensitive to dirty mains and spikes and would make random popping and electrical noises. As you mentioned it extracted a lot of detail out of the source, but it wasnt very clean. If you had a hissy tape you would hear a lot of hiss. In contrast the Cyrus 2 was very clean and stable for its day. I use to run it through a pair of Monitor Audio mid floor standers. Cant remember the model but they were deep and came with small stands. That sound was very authoritative with great scale.and timing. Great memories thank you.
You can get the speaker output plugs changed for modern binding posts by your friendly local engineer but I appreciate this lowers value as it makes them non standard but is beter really. I may do this with mine.
Excellent as always , thanks kelvin
I think I need one of these. I have the Leak 3400 which I love but this looks more fun snd juvenile.
its a total hooligan
Imo the stereo 30 was the best leak transistor amp and the best sounding was the first gen with germanium transistors and that was according to my 20yr old daughter who actually had full hearing capabilities. But both types were really good with early Kef Celeste’s anyway.
+1
They use modular pcb sections that plug in to a motherboard... these sockets get a bit dodgy over time
I'm considering it in combo with a pair of old Goodmans G Mezzo 3's. I use them with a Pioneer SA - 408 now.
They have an excellent space but the upper mid range is a bit too much and th every high's are not very pronounced.
Do you recommend to switch, or with this amp the upper mid range will be even more strong?
Thanks!
I picked a leak stereo 70 up the other week for £20 iv dropped it off at a repair shop to be checked out before i try it out, hopefully not a lot wrong with it, i really wont to try it out and like it id love one of them mission Cyrus amps vintage amps and speakers have got me i can ot stop looking at them, i love your videos they are great
Hi Michael glad you’re enjoying the channel let me know what you think of the leak when you get it is something else
K
I think im going to go for it on the repair and recap of my leak 70 and get all of the plug ins changed in the back so i can just plug everything into it RCA and banana Plugs for my speaker's i love your video on the spender bc1 im listening to mine as i type im running my quad 303/33 it all sounds fantastic to me you have got me wanting some Rogers LS3/5A now the misses got me some kef cadenza speakers for my birthday i love ber lol great speakers do a video on the nad 3020 i think its a classic id love too known your thoughts up on them keep up your great videos they are great
I got my leak amp back just before Christmas and it really dose sound fantastic iv played it every day since picking it up from the repair shop
wow...20 pounds? would love to get one though
@@michaelharris4389 can you tell me where that repair shop is please
If you're using a CD player with it you can't go full volume because it's over driving the pre amp.
The CD line level out is well in excess of the max input sensitivity of the amp.
Try some attenuated phono connectors or the sensitivity switch on the back.
I have both the 30 plus and the 70. I need to get around sorting the 70.
The best thing to do with them is gut them; remove and bin all the old capacitors, all of them, including the film caps. Bin all the now well drifted carbon composite resistors and pots, and bin the driver transistors.
New uprated Panasonic FM FC, electrolytic caps throughout, new PSU reservoir and Decoupling caps, wima and vishay MKP, new metal film resistors and I can't remember what driver transistors I fitted, new pots and finally some decent phono and speaker connectors. oh and new rectifier diodes, buse the uprated PSU Caps will destroy the old ones.
Some might say "that's not how Harold Leak intended it as you're changing it all".
Well, the ones with all original components in them are less like how he intended as they are all well out of spec even new old stock.
The difference will be night and day and for me it was worth every penny beautiful lovely detail and calming. Listen if you want to relax at medium volume and hear the music.
Oh and make sure you have a really good source.
Not worth it if you can't rebuild it yourself.
Get attenuators for cd playback.
Wow! I'd been wondering about Leaks. There are always quite a few for sale near me, and usually for little money. How do they sound in comparison to the Sugden you reviewed?
Matt. When I bought my FIRST CDP (AR CD04) in 1987 I pitted my then Leak 2200 (mid 70's) against a Dealers Sugden A48 (overhyped IMO) and the Leak was much better all round......punchier, sweeter, better bass. Was expecting the opposite to be honest.
Bought a Leak Stereo 30 Plus for 55 euros in Spain and had it serviced back to brilliance! Its the amp Jimi Hendrix had in his home in London that's now open as a museum with Lowther speakers and a Band and Olufson turntable plugged to it. You should get hold of one and see what you think....it's impressive!
Yes I’ve seen that photo of Hendrix and his stereo
@@stereoreviewx try get hold of one. I have both and there's something great about it perhaps your experience can tell us about
Nope! He had a Stereo 30, not a PLUS! He and Barrett had the same amp. The only one with Germanium transistors. When you hear one you get hooked to that damn thing ... The Stereo 30 Plus is nothing but a simple integrated amp with average sound.
@@sirnosedavoidoffunk I stand corrected.....was only based on what I had read. Here's what HIFI NEWs say: "The Stereo 30 used germanium transistors because that was all that was available at the time. They worked but were noisy and prone to thermal runaway, making it a challenge to design practical hi-fi amplifier circuits using them. Nevertheless, the Stereo 30 was well regarded and sold successfully until the appearance of silicon transistors in the middle of the decade signalled a step change in amplifier performance. Quieter and more stable, silicon made it possible to build high-gain, high-power circuits with relative ease. The Stereo 30 Plus was essentially the original concept built around a complete lineup of silicon devices. It was the same, only better.
What would be the purpose of having two mono buttons.
I'm very interested how do they sound in comparison to the Sansui AU101.? Both have a very similar electrical circuit.
The difference is in the supply voltage of the Leak 74 Volt, Sansui 44 Volt. Leak has a larger output capacitor. Probably better bass. The rest is the same. The question is who copied whom.
Yeah I got the sensory 101 the difference is very big the leak is hugely bold and big in the base and the mid range Sansu is delicate fast light on its feet.
K
This is the holy grail......classic Brit sound. Most would pass these days, I believe. There is a hipster 130 now, but only in name. Those terrible hipster diseases.....
I have a Leak Stereo 30 Plus (bought for 55 euros, needed service) and a Stereo 70 - bought for 90 euros (needed service) and Leak Mini Sandwich speakers (have put in a new crossover)
You should try and get hold of the Stereo 30. It should sound somewhat different as it uses Germanium transistors.
the Stereo 70 has germanium transistors.. the Delta 70 has silicone transistors
@@cameronkrause4712 NOPE!
@@cameronkrause4712 the stereo 70 uses silicon transistors - like bc148, bc149, bc107 etc in the pre amp and some beefy 2n3055s among others in the output stage. The schematic is available on line. It’s quite a complicated design. As far as know the delta 70 and the stereo 70 are pretty much the same design, just a different chassis. EDIT. On further inspection, it’s not that complicated after all...
Much prefer your reviews to the modern magazine Reviewers BS such as brightly lit, macro dynamics, micro detail ?? etc. and other words we DO NOT understand.
Thanks for that k. I did plug in headphones and it did work on both channels. Though still no sound from Left speaker. We used to smack the side of our old Grundig tv once in a while I remember as a kid and the thing would always come back to life until one of the valves would blow of course and we all knew a guy who knew a guy who doubled up as tv repair man in his spare time and would do the deed in the middle of our living room for peanuts... sorry I went off on a little tangent for a there... was referring to my sansui 331 above
Swap the speakers over that will tell you if it’s the amp or the speakers
Had to do an Elvis special with it - ‘return to sender’. .. but the sound out of myTannoy speaker has never sounded so warm and not leaving me ‘wanting’- even though it was one functioning channel out of the mighty 331...
@@stereoreviewx Sansui S-65 on e bay now... 12" woofer, 4" midrange, and a 3 inch tweeter. All tested working fine, apparently! I'm guessing these are not great as unable to find much positive vibes on line....Look beefy though...
When people came in and asked what an amplifier sounded like we would connect one up and let them listen.
Reviewers that worked for Hi Fi Magazines would always argue that an amplifier should sound neutral.
A straight wire with gain was coined as the perfect amplifier.
Then makers went mad on eliminating all switches and tone controls from the signal path they were removed completely.
Bare naked amp with a volume control.
Jeremy Travis _Straight_ wire with gain. Coined by Peter Walker of Quad.
@@EJP286CRSKW Typo Corrected. John Linsey Hood also used it.
Hi Kelvin, I've acquired an old Leak 2000 amplifier. It seems to switch on but that's as far as I've gone with it. Its in terrible cosmetic condition, do you have any experience of this model? I suppose my question is do you think its worth sorting out ?
Well I would look for fuses internal fuses I mean it’s probably never going to sell for a lot of money
They are quite easy to work on for the most part, the electrolytic caps are past their best and often a cause of problems. The push switches on the front/back generally need some contact cleaner, along with the volume/tone controls, they all carry signal at some point. If the lights don't come on when you power it up make sure the bulbs aren't loose, they have a habit of backing off.
Once serviced, the Leak 2000 sounds very nice.
@@SeasickUpload cheers for the information, I'm planning to give it a good going over. I'll let you know how it goes.
These kind of amps are really for vintage lovers only who want to feel like at the time these amps were built. They are comparatively cheap nowadays BUT it’s another thing if you really want to put something like that in your regular system - if you’re not a collector of that kind of stuff. On the other hand these amps (like all amps) also take space and collect dust. That at least for me is a reason to only have the amp I really want to listen to all of the time. But there certainly are different views/ approaches out there...
I have lots of amps and always end up listening to the same few ones, mostly Leaks from the 50s and 60s and it's not a nostalgia thing.
I own a Sony TA-2000F and TA 3200F fully revised and mint condition.
They are made 1971 and they sound detailed, rich with a wide open stage, full spectrum.
I also use a modern avrDenon X6400H, which sounds different, straight forward bass , less detailed, smaller stage.
Not bad just different but i prefer the way the old Sony's reproduce music .
I was surprised and impressed how good this old stuff sounds.
A bit different is my experience with loudspeaker:
You can get good loudspeakers made in the 70' s or 80' s ( like my KEF 103.2 reference or my Rogers Studio 1a) but it is much easier to find good loudspeaker made in the 90's as technical progress made it easier and also cheaper to produce good loudspeaker.
I really enjoy watching your videos and looking forward to see more of them
regards
Oliver from Berlin / Germany
The reason it takes so long to get working is most likely capacitors reforming, I believe this is germanium Transistors first generation they were never the greatest. Still a very impressive amp for the time I have some Armstrong amps of a slightly later vintage I have restored a few of them might be worth a look.
Nope, it's not a germanium transistors amp.
@@sirnosedavoidoffunk that was the earlier Stereo 30
The amp uses germanium transistors. Is silicon that we currently use in almost all solid state designs the "inferior semiconductor"? 🤔
No no no! You are wrong. Germanium only in STEREO 30.
Enjoyed watching this. I always thought these sounded pretty rough and Leak had at this time been bought out by the Rank organisation and nothing would be the same again..Compared with a Stereo 20 from the year before, blimey I always thought about people 'upgrading' to the latest Leak at the time. Must have been an awful disappointment. For people looking in re. ''old amp not working' there is a certainty the switches will require a clean. These Leaks have a whole bunch of switches between the source and amplifier actual. Cleaning these will solve 90% of problems and improve quality by same amount. The other thing is of course the state of the electrolytics. The silicon or germanium devices will either work or not and are mostly reliable.So if it is generally giving a clean output with no hum or noise, clean switches and pots.
Thanks for that
I actually have a 2004 year model NAD amplifier and it is obviously solid state but I really think it sounds better after some heat builds up in it. I know that's counterintuitive but I'm positive it's so. It isn't a figment of my imagination. On a side note I've been wanting to pick myself up a Cyrus 2 but I just haven't found one I like yet. I prefer to buy from electronic techs that service and clean them and put at least some warranty on them.
Hi Kelvin.Would you happen to have one for sale?
It would stand a mild update. Baxendale diode to quasi output stage. 250 VA toroidal transformer.. Better quality but same size capacitors. Capacitors in general. Don't retain the transformer and fit big capacitors . MA4, yes please.
I detest loudness boost, for 1 it's too high a jump and 2 if you have weak recording and turn the vol knob over 6, the midrange honk kicks in
j ai cette ampli avec les sandwich 600 c est vraiment exceptionnel ,et je partage votre ressenti sur se leak stéréo 70 ,et je suis encore en hésitation entre lui et la série Kenwood l 1000 m-c-d qui est aussi exellente mais haut de gamme pour vous dire que cette ampli est vraiment surprenant
Moi aussi, j'ai le Stereo 70 avec les Sandwich 600 🙂
These were produced 1968-72 before the Rank takeover. I doubt that HJL designed it himself.
Sounds like it just needs a good recapping job... It should sound work perfectly after.. And might sound even better. Leak was good stuff.
Is this product similar to Nad 3020 amplifier ?
It doesn’t sound like the niad exactly which I have had it’s bigger and bolder .
Both have great bass grip.
The night is smoother bit more sophisticated and you can listen to the nad all day It’s less tiring I mean
sorry have to say,if on turn on amp is not good for that long?Then its probably going to be one that has never been maintained,capacitors,dont last that long,you could only A/B this amp,if it was re-capped all.And cleaned all pots and switches.
Capacitors might need to reform and push buttons will need contact cleaner then bombproof. Harold Leak always aimed for less than 0.1% distortion from his earliest post-war designs. Try pairing with original Leak Sandwich speakers which were decades ahead of their time using stiff cones and damped cabinets.
Nice review.
Very correct.
im guessing this needs a pre-amp?
No it’s an integrated
What is deoxy or whatever you said?
It cleans the dirt of the contacts and especially the pots (electronic parts of the volume controls).
Better off buying and fitting new pots if you can find them and fit them.
Thanks for that. M
Leak - класс , мой-30 , видимо , где-то долго хранили.
I love my cyrus 2
Leaks behave like an old diesel engine.
It takes a lot of time to run.
Like me on a monday morning after
a hot weekend in the late Sixties..
Hello HiFi friend from Serbia.
Please don't take this the wrong way, but when I've seen your reviews they've been comprised solely of your talking about the product.
You;re not alone in this, but when I click on a review I'm expecting to hear the product being demonstrated. Is this unrealistic in your view?
I tried it by the time it’s comes out in your house it’s been quite changed
By microphones and you tube
Amp design is obviously a black art. They definately just didn't keep getting better and better.
It's difficult to really provide an accurate picture of a leak st70 in any review unfortunately..nor of any piece of vintage kit that age. The reason is that with almost certainty the components internally will be miles out of spec...caps esiecially but even transistors of that age were notoriously unreliable. I have a similar Leak in my collection but wont fire it up until I can get around to servicing it. Once done they tend to sound better and there's less chance of any dc offset due to drift frying your speakers😉
Well kind of true but you can still tell the general sound and I have had a few of those leaks so I kind of generalise based on a few experiences
This amplifier and the delta series that came later all used quasi complementary output stages and therefore produced odd harmonic distortion. This distortion produced a sibilant sound which was quite unpleasant.
Do you own one?
@@jeffsimon9594 Yes I did back in the 1970's. I then moved on and designed dc servo power amplifiers with lateral power mosfet output stages. Vastly better sound quality compared to the old Leak amplifier. Harmonic distortion 0.01% and frequency response within 0.1dB from 2Hz to 60Khz. Output power 272W into 8 ohms and 450W into 4 ohms. Each channel has it's own 625VA toroidal power supply for dual monaural operation. I have two of these stereo power amplifiers driving my Tannoy's in bi-amplified mode. The result is stunning with astonishing detail and kick ass low distortion clean bass.
@@jimdavis5230 Sound quality is subjective
It's quite a long (and eyebrow-raising) story which I can link to if you like, but old Harold did not design the Stereo 30 / 30+ / 70 etc
If the Beatles loved it, it's legit
If my memory serves me correctly the leak camp is what Jimi Hendrix had and it’s in the Hendrix house here in London I think I have that right.
@@stereoreviewx Syd Barrett had a Leak Stereo 30.
I have one of each of these amps. I prefer the Leak.
I don't have to let it "warm up" for half an hour, it works perfectly straight away. There is no hum. What I'm saying is the amp you reviewed seems far from healthy and as such, this wasn't a fair review. After all, no one would take a car review seriously if the test car hadn't been run in years and had worn suspension and brakes and the engine needed a rebuild, it wouldn't be representative of it's type.
The "missing centre image" isn't something I've experienced with mine, nor the inability to go loud. It becomes uncomfortably loud long before noticeable distortion sets in.
What I do agree with is the "up front" sound characteristic, the mid does tend to be strong although this isn't to a problematical degree. It appears to be a characteristic of early solid state hi fi amps, my Rogers Ravensbourne is the same. As you said, careful speaker matching pays dividends when using devices such as these.
The Cyrus. Technically it's a more "correct" sound, the amp melts into the background and adds no characteristics of it's own or at least to a much lesser extent than the likes of the Leak or the Rogers. It seems pretty much bomb-proof although it's worth bearing in mind the speaker output protection leaves a lot to be desired. Like the Leak and the Rogers, on the Cyrus the only output protection is a fuse for each channel. I'm given to understand sometimes the fuses aren't enough, they don't act quickly enough and the output stages can become cooked at very short order!
I find the Cyrus less flexible than the other two amps, no mono switching, no tone controls, basically a power amp with input attenuation and a (very good) phono pre-amp. It's gutsy enough and involving to listen to but I just find the Leak more exciting to listen to, frequency imbalances and all!
It's true that solid state hi fi was still in it's infancy in the late 60's, the basics were there but the execution still needed a bit of work. The state of the art would still be another 5 or more years in the future but at the same time I can't help thinking something may have been lost in the process...
Thanks for your comments very interesting regarding the leaks temperamental behaviour I’m just trying to warn innocent people that these amps are often not functioning good.
Could you tell me your favourite and for any other insights about whT sounds good old or new cheers K
@@stereoreviewx Ok, 2 amps I regrettably no longer own: FAL Phase 44, 1969-73, 20 watts RMS per channel @ 8 ohms, same left/right mono switching arrangement as the Leak, amp sounds much more powerful than it is, doesn't have the typical midrange heavy early transistor sound but tending toward a warm sound.
Trio KA4002A, 1972-75, 25 watts per channel RMS @ 8 ohms, physically slightly smaller than the Leak but has even better facilities, 2 aux inputs, 2 turntable inputs (although both same sensitivity) 1 tuner and 1 tape loop, pre-power inputs and outputs, not sure now if it had a mono output for subwoofer, very solidly built and sounded quick and modern.
I severely regret parting with these amps! They both sounded awesome playing through Wharfedale Dovedale mk3 speakers. The Trio fed with an Ortofon VMS3 cartridge in a Pioneer PL-512 turntable sounded better than it had any right to!
The PL-512 was a budget deck. They had an rrp of £49.95 in 1979 and were a development of the earlier PL-12-D which I also owned at the time. However, due to clever plinth design, gone was the PL-12-D motor rumble.
The PL-512 was for the time a minimalist deck. Totally manual but powered by a mains synchronus motor, it at least featured a mechanical speed selector instead of having to mess about removing the platter and refitting the belt as with some later minimalist designs...
I still own the 512 and although it's fair to say it's cosmetically challenged (I obtained it with burn marks in the lid and the plinth is grubby and wouldn't even clean up when I tried oven cleaner on it!) it's been absolutely reliable, never goes out of tune no matter how long it's left unused for and fitted with an Ortofon VMS 10E cartridge, is kind to records and gives suprisingly good, stable stereo imaging.
I've got a house rammed full of this kind of stuff dating from about 1965 - 1990. My mates call me eccentric. They also call me when their stereo gear fails them because I have a soldering iron and a multimeter and know how to use them...