JA! Sehr gutes Zeug und extrem weit verbreitet bei den Leuten, die damals Wert auf ordentlichen Sound gelegt haben. Die anderen hatten alle diese fürchterlichen Kompaktanlagen. :D
I always put a 120mm fan on the top of my amp to help the heat out. It won't need to spin very fast. I run a 12v fan at 5v (USB) and i can't feel any heat when touching the top of the case.
That's a good idea. I remember some amps from the era (especially Technics) had fans pre-installed from factory to keep the transistors a bit cooler. Most of them were temperature controlled even. :)
90s stereo equipment! Back in the day we need substantial hardware to enjoy our music. These days people listen to (mono)blue tooth speakers or in ear headphones, it's actually quite crazy!
Yeah, the younger generation doesn't appreciate the old school sound for the most part. Although there are exceptions, as witnessed by the recent vinyl revival and such. Plus, I have to admit that the modern headphones and portable speakers sound a lot more decent than what was available during my youth. But they are still no match for a decent analog amp with large speakers actually moving some air. ;)
Since the 70ies everything is being downscaled - just take a look at the big receivers of old. 90ies were good but it was the decade were things went downhill.
@@JanBeta I think it is still in active use, why do I think that? I had to sell it many many many years ago because of money problems, like so many other retro things. But one day... I will get it back. Sad story, I know, but that's life.
Nach einigen Jahren herumprobierens diverser Reinigungsmitteln für Switches und Potis(für das Metallteil) bin ich bei Edelstall- und Chromepolitur für die Küche gelandet. Es entfernt jede Oxidation in sekunden ohne die Oberfläche aufzurauen. Auf Wattestäbchen auftragen und reinigen, anschliessend mit Wasser und danach Isopropanol spülen.
Ah, klingt nach einer guten Idee! Radiergummis funktionieren auch sehr gut, aber für heftigere Verschmutzungen ist Politur sicher eine vernünftige Lösung. :)
oh jan! i had the same generation of Sony amp back in the day, I was only 16-17 at the time i bought it i had to pay it off (lay by) and sadly had nothing but troubles with it and had to return it several times as it was dead. it eventually did get fixed.
Oh, you must have gotten a bad one then. In my experience, the Sony stuff from the era was really decent most of the times. I had a lesser model myself around that time and I absolutely loved it.
I know this video is pretty old, but 10 - 15 minutes is not really enough before setting the bias. I found that after an hour it stops drifting. I would usually hook up 2 multi meters at the same time for each channel, and at 30 minutes start to tune it, and keep on checking and tuning until there is no drift for 15 minutes.
Hi I have the same model amp and have the same intermittent sound outs . Really interesting and informative vide. I will try cleaning my solenoids if I can get them apart.
When things were just knobs and switches, rather than menus and pre-sets, audio gear manufacturers certainly lost their way as technology changed, going from serviceability to "bang it out cheap and maximise profits!!!", all at our expense...
I think there's still some manufacturers around these days that deliver decent quality, unfortunately mostly on the very high end "audiophile" and vastly expensive spectrum. Times have definitely changed. :/
Gott, ich hab die Quellenschalter schon Kohlrabenschwarz gesehen. Wichtig, die Kondensatoren vor dem STK3102II leiden und wenn die sterben, stirbt auch der STK für den es nur sehr schwer, wenn überhaupt Ersatz gibt. Ansonst sind die ES Geräte von Sony echt toll. Das leidige Relaisthema.. man kann die reinigen, aber will man das überhaupt. Es gibt ja Ersatz. Ansonst schönes Video.
Hope you enjoyed it! I love to tinker with audio electronics from time to time. The channel actually started out as a vintage hifi channel before I got into retro computing. :D
I don't want to disassemble the switch after watching the video. I think it is safer to clean it with vinegar without disassembling it. Using an ultrasonic cleaner will shorten cleaning time. Then rinse with alcohol.
I have a sony F311 on the list of repairs needed. I just love the look of sony equipment from this era. Similar issues with switching and a bit of cracking or loss of channel when i move the balance. Might put it on the list for this weekend now you motivated me 😉
Chances are it just needs some contact cleaner in some strategic spots. The pots and switches in these are usually the main problem if you get noise and crackle in the signal. Hope you manage to fix it!
@@JanBeta I am not really familiar with audio stuff so had it on the backburner and was a bit reluctant to even open it up. Seeing you work on a similar model does give some good insights. Didn't know about setting the bias so a little bit more knowledge gained from you.
That's quite non-trivial but doable. As far as I know, you basically feed the amp a 1kHz sine wave at line level, monitor the outputs on the speaker terminals with an oscilloscope and then adjust to the point where there's the highest output before the waveform starts to clip. Not 100% sure if that is the "professional" way to do it (because I'm just a hobbyist myself), so please do some research before attempting something like that. It's very easy to blow up the transistors in case you set them up incorrectly.
Yep, the voltages (actually 7mV, 7V would be WAY too high) and the whole procedure is described in the service manual. You should be able to find the exact service manual for your model online, too. Highly recommended to read through the thing before you start working on your amp. Sometimes there are some peculiarities you have to keep in mind before changing anything.
My Kenwood receiver from 1999 only has audio through the headphones jack. Not through the speakers. Anyone has a diagnoses for me? For many years I left it on standby instead of shutting it completely off with the other button. My bad!
Depends on what model it is. If it has a dedicated headphone amplifier, there’s likely something wrong with the power amp section. If it just derives the headphone signal from the regular power amp output, maybe you have an issue with the relays or somewhere else in the speaker protection circuit.
New sub. Love these older Sony amps. I hate the newer ones; ever since the Sony Corp. of Japan decided it would be cheaper to have their stuff manufactured in Mexico, and other such countries. The build quality went RIGHT down.
The interior of that amp looks so good. It looks carefully designed and assembled. Well worth your time to bring this amp back to full function. I hope you enjoy listening to music with it. Cheers!
I use a T-AF630ES....in storage for 15 years runs like a charme when revived. The ES series was the top range of Sony. Can run 4 and 8 ohm speakers. I had 4 ohm 401 on them back in the day until these died. Now I'm running 8 ohm Yamaha's. And a Sony 55ES, will buy a Sony CD player of this range soon. And a Technics turntable of course.
Ahh, the sound of alcohol soaked q-tips on metal contacts... Anyone else getting goose bumps all the way down their spines? It's like chalk on a blackboard! :D Nice repair! Reminds me that I really have to clean the potis in my old Fisher amplifier. It's not as fancy as this Sony, but it still has a decent sound for being, like, 35 years old or something... ;-)
I have the TA 700 es - it's a wonderful amp ( weights a Tonne ) had it serviced recetly . The engineer said that to buy a n amp of that Quality today would cost thousands , I got mine for £200 from Fleabay. Best thing was the Tape monitor function , My amp is connected to a Studer Reel to reel and an Aiwa xks7000 Tape deck. Love me some Analogue sound
Don't have sony always been a marantz man I have the model 9 at the moment have a model 2 in storage that my wife wants me to sell I may just tell her I did 😂. You are correct about vintage equipment much better built with a beautiful unique sound that modern stuff cannot touch in my humble opinion.
Back when Sony made heavyweight amps. My two home cinema receivers from the early 2000's are poles apart. Both look outwardly similar, but the older one is far more substantial internally. Not everything improves with miniaturisation.
Yeah, they don't make them like that anymore unfortunately. Thankfully most of the 70-90s stuff is still serviceable and can be fixed these days. I still prefer the old equipment over any new receiver/amp, even if the newer ones are a tiny bit better technically (regarding signal to noise etc).
Pretty nice amp, those MUSE caps are decent. Btw that STK ic can be rebuild but it's a lot of work. This is the problem with these amps using these STK or RNS ic-s, like Technics, Panasonic, etc. These ic-s are very difficult to find, and sometimes this is the reason why these older amps getting thrown out, the lack of that ic and too much hassle to rebuild.
I love 90s Sony separates. So cool. My parents had the full stack. Amplifier, record player, dual tape deck, cd player, and radio tuner. Same era as the amplifier you showed here but theirs was a higher model. I'm pretty sure it cost them nearly 2 grand back in the day! And they still have it all. I'm pretty sure it will be mine one day. I cant wait to service it and play around. Really enjoyable watch Jan. Good work.
Great video thank you, the diagnostic path really helped me. I mange to get my relay board out without removing the front panel by; unscrewing the transformer and sliding it to the rear, removing the trace board, sliding the transformer towards the from, removing the relay board. I didn’t need to remove the transformer wiring but had enough slack to tip the relay board over for its removal and clean. Wouldn’t have attempted any of this without your video so thanks again.
Why in the world did we move away from these designs, e-waste levels had to be better back then when things could be repaired. I mean, I get the power issue, it’s maybe 30% efficient, but there’s gotta be a tradeoff for that efficiency. Though I guess nobody listens in stereo anymore, mono on a crappy Bluetooth speaker. I’ve done several “make it sound good on my phone” mixes and cringe when it all goes center to mono.
Most of it is due to maximizing profits I guess. I still have a bit of hope that eventually the "right to repair" movement is going to succeed in more significant ways. Would be better for the planet as well as for us tinkerers.
Nice job Jan! 👍🙂 I was doing basicaly the same on a Sony TA-F490 while watching your video... Without desoldering or replacing protection relays. On the part of disassembling the input or source switches there's not really a trick but you have to be really careful in taking them apart for not breaking anything and making a tight fit possible when reassembling.. Keep up the good work! George
Excellent video Jan. Great job repairing/restoring the Sony. I'm on the tail end of the same task with an old Pioneer A-447 stereo amplifier that I saved from landfill. It spent the majority of its life in the front bar of a hotel, a lot of it during the times that smoking was still allowed indoors. I even went to the extent of stripping it apart to send the chassis off to get electroplated in gold zinc. Repairing 1990s tech is so rewarding. The electronic repair wasn't too bad... but restoring the amplifier back physically has been quite a journey!
For those potentiometer tabs I would try a vice to crush them in or a hammer and tapered chisel or tap to hammer them down flat. The vice may work best for the control it offers but may not be able to bend the metal in a specific direction as easily as the hammer method would. (PLEASE! Do not use superglue(Cyanoacrylate) on electronics. It's corrosive and it gases Cyanide while curing which is also corrosive. It's also a jerk thing to do to the next service guy who comes along to fix it.)
Bias must be adjusted in room temperature which is 21-22 Celsius - your room is far too cold as shown on your multimeter which was only 14-15 degrees 🥶 you must adjust it again. STK and some of the TO-257 transistors also resolder for dry joints. Always the same in thouse Sony.
Good call! I’m going to double check. I think the room temperature was slightly higher in reality (the multimeter is a couple of degrees off usually) but it still wasn’t 21-22C. Thanks for pointing that out!
@@JanBetarember also to resolder the STK ic and all the TO-257 housing transistors - the almost always have dry joints. Very importen. If the STK3102 break, replace it with STK3152
The room temperature reading on the DMM is usually a couple of degrees off, it was probably more like 17C or something. I have the window open and the heating turned off in the lab most of the time because of the soldering and contact cleaner fumes I produce. :D
Incredible Video. Thanks. I have this amp and the attenuator when turned is erratic, usually actually turning volume down or off. I’m thinking this is the potentiometer and wonder is it possible to treat that without taking the whole appliance apart like you did and if so how? Thanks.
I think you can get in with a contact cleaner can that has a long straw. Should be possible to get to the openings in the potentiometer from the side of the front plate (after taking the lid off).
Judging by the amps I’ve worked on, they were quite commonly used in the early to mid nineties. Marantz did it a lot, in the PM-50 for example and some of their higher class amps, too. I guess it was a relatively inexpensive way to get good quality driver circuits at the time. Many STKs actually sound great and have good specs, the only trouble is that they often break because of heat/too tight integration. At least most manufacturers seem to have stopped using them as the power amp modules at that point. :)
Jo Jan! Das Video kam genau zur richtigen Zeit! Ich habe den gleichen Verstärker und dein detailiertes Video hat mir wirklich sehr geholfen die Relais zu tauschen! Mein Sony spielt jetzt wieder wie neu. Tausend Dank!
Hi I want to replace some parts sony es amplifier, need audio grade capacitors like ELNA,Nichicon and resistors etc. Where can i find these online? I am in Europe.
I usually use Panasonic FC or FM capacitors, available from Reichelt.de for example. If you want to go full-on "audiophile", mundorf.com has you covered. Resistors etc are available from Reichelt or Conrad. There’s no point to go too high quality/price though. As long as the parts meet the specifications, you are not going to get any better sound with esoteric audiophile stuff, it’s just more expensive. Good brand, properly specced parts are the way to go in my opinion (and experience).
Great Video thank you. Maybe it would be better to work with an 1 khz Sinus signal at input for testing and an osziloscope at the speaker out connectors. Then you can see every problem very quick. 100 % would be 4 or 8 ohms power resistors for load.
Yup, would have been a good way to test things usually and I’ve done that a couple of times in previous videos when testing amplifiers. In this case, I had already heard the amp before I got it on the bench and was pretty sure about the fault(s) so I decided to skip that step. :)
My friend... Sometimes it's the things you say that you may just assume that everyone knows that can make a headache repair an easier job. I'm working on a Sony as well, but not the same model. But they seem to be different versions of the same thing . Thank you for doing this one. One question... Why the baking soda with the super glue?
Thanks! Glad this was helpful! The baking soda acts both as a filler (to build up extremely solid material) and as an instant kicker for the cyanoacrylate glue. It's an old trick from the model making world, actually (I learned it a while back from Adam Savage's channel). If you haven't tried it, I recommend doing so. It's kind of a game changer. ;)
One, often overlooked, aspect of relay replacement is coil resistance. It is prudent to ensure, the value isn't appreciably lower, than that of the factory fitted. Moreover, holding and must drop-out voltages may differ, which can lead to timing issues under certain cicumstances. Then there's contact material variation, which again, affects performance.
Good point! I found the ones I used recommended as replacements in several forums and the resistance doesn’t seem to be too far off. Would have been worth mentioning of course, thanks for the tip!
Hello, can you comment on the weird and thick base of this amp seen in the video? It looks like a concrete bunker but is surely not a Sony G-chassis at this price point.
I think it might actually be what Sony called a "G-chassis". This amp is from the ES series after all. It's just a metal frame covered in thick felt to minimize vibrations, no concrete or extra weight or anything like that involved. I've not seen any other amps from that series from the inside so I'm not sure if there's something else they added to make it a real g-chassis. Certainly, the felt helps a bit with minimizing vibrations but I would guess probably close to unmeasurable, more of a marketing thing from Sony.
Can you imagine when they assembled these, how many times folks put in the transformer before putting in the speaker terminal board. Then having to take out the trans lol.
My guess is that the board makes a more reliable connection and offers the shortest possible signal path. A ground plane in the board also offers better shielding than a ribbon cable. So it’s actually a good idea to use that strange board. :)
The baking soda just acts as both a kicker (to make the glue stick VERY quickly) and as a filler. The result is a very solid plastic-like material. It's a quick and dirty method to get the superglue to become extremely robust and fast acting. It's widely used by model making hobbyists. :)
Ah this is great. I had never heard of this! I build a lot of models and use 2 part epoxy a lot but never this trick. Thanks again. People like you is why RU-vid can still be great. @@JanBeta
Oh, some of those STKs actually sound extremely good. They were used in many higher end amps at the time for driving the power amp transistors (I know that at least Marantz and Denon used similar circuits in some of their higher end models, too).
Very interesting, I own a Denon PMA-560 amplifier that I've had since 1993 and I know it has some dust in it's contacts but since it pretty much just sits connected and i never really do anything with the selecting switches or pot meters anymore (all settings are handled before the input from an external sound board) I havn't really thought it necessary to do anything about it yet. The front layout of the amplifier in this video is remarkably similar to mine and watching this I think I'm about ready to do my own deep cleaning on mine. Thank you Jan, always fun and informative to watch 😊
It's a matter of comparing data sheets usually. You want something with similar values, especially regarding voltages. In this case, I found the replacement type by reading some older forum posts where people had successfully used this type as a replacement. Which is always a nice reassurance. ;)
Many thanks for this video, I like amps from 90s era , that is why I have bought my ADCOM GFA 555MK2 and 545MK2 , They are phenomenal amps ,sounds awesome and build like a tanks.
Hi Jan. I just bought this amplifier used and I have followed your guide. Thank you. I did notice that you didn’t mentioned the RCA connectors on the back. Mine had cold soldering so that the left channel dropped out every now and then. So my advice is to resolder the connectors to the PCB.
You have to admire how these were put together. Its like Jan says - "Built to be repaired" , Don't suppose many amps are built like these anymore . Good Job, you can do mine next time ! LOL
Even if Amps look repairable these days they remove part numbers off components in many devices that make them difficult and potentially hazardous to fix. I was trying to see if the schematic was in the lid like some of the older amps.
Yeah, different times. The 90s stuff is already less serviceable than the earlier devices but still reasonable to work on. Modern equipment often isn't reasonably fixable at all unfortunately. Unless you replace the whole innards or something.
Yes, definitely a higher end amplifier. I didn’t fully realize that while I shot the video. It’s very well made but relatively generic inside so it didn’t occur to me to be particularly high end. :)
@@JanBeta Real high end stuff are often very simple I guess :) I think the only problem of these amplifiers were its switches, which Sony and probably most other companies changed for relays after this. And ICs on lower end models of course :) But you did a great job fixing these problems!
Stimmt, von denen habe ich sogar schon mal Ersatz-STKs bestellt für einen Technics-Amp, den ich vor Jahren mal auf der Werkbank hatte und für einen Marantz PM-50 (der benutzt einen STK als Vorverstärker, so ähnlich wie der Sony aus diesem Video). :)
Baking soda is very messy. There is a super glue accelerator spray which bonds parts in few seconds :). You could have used water pump plier or vise grip to press the parts tighly together. My hats off to all of your commodore repairs :)
I love using baking soda to add some body to the glue. The problem in this particular case was to make the switches still moveable while getting the contacts as closely together as possible. Clamping down too much wouldn’t work because they would get stuck. So far, my workaround works very well. Hope it’s going to last. :)
I think most of the amps from that era need some cleaning and general TLC at this point in time. Most of the times, a bit of contact cleaner in strategic spots is going to resolve the issues at least temporarily in my experience. :)
Genau diesen hatte ich auch. War ein tolles Teil, was ich sehr lange genutzt habe. Wurde erst ersetzt, durch einen 5,1 Reciever Toll, das du den reparierst
The transformer, though round, is not necessarily toroidal. In this era, Sony put traditional squarish transformers in cylindrical cases to make you think they were toroidal, at least according to one authoritative source.
Hi Jan . I have a Rotel RA01 amp. I am going crazy with the hum from the phono stage . Even if there is no turntable connected , the hum is still very loud . If there is no cables connected it goes quiet , but as soon as I plug in two phonos ( even with nothing connected at the other ends ) the hum surges .. Is my phono board ruined ? Can you help ?
Sounds like a grounding issue. I didn’t find any info about that particular Rotel but it probably has a ground screw for the phono that has to be connected to the ground wire of the turntable. If you just connect cables, they are going to act as antennas basically and pick up all the noise of the surroundings which then is amplified by the phono board. So the hum is normal. With a properly connected turntable the hum should go away. If that doesn’t help, maybe there’s an internal ground connection missing on the phono board or there’s some bad capacitors in the amp.
@@JanBetaThanks for quick response Jan . Firstly, the Rotel RA01 was a great amp from around 2003 ( won what hifi amp of the year somewhere I think ) ..I have a Teac turntable 300 from around 2015 .It's a fully modern turntable with no earth connection on it or even needed. The amp has an earth bolt provided . The problem happens as soon as any pair of phonos are connected to the amp, even if no turntable is connected at the other end . When I do connect the turntable, it goes down a little but still very present and unlistenable. I'm sure it's not an earthing issue Jan, it just happens when a wire is connected . ( With no phonos connected at all , all is quiet ) but I need my turntable . If I knew what and where those capacitors were , I might have a go at replacing them myself ...can you help ? Thanks anyway 😊 0:44 0:44
@@JanBeta Hi again . I looked at the circuit board just below the phono stage on the Rotel amp and couldn't see any bad soldered joints ( although I don't know what I'm looking for ) . After I put the case back on again , I tried another suggestion I was given using a mobile phone . I used my 1 metre long stereo phono ( red & black ) cable with a stereo 3.5 mm jack at the other end ... I used a phone radio app , found a station , turned the volume ( on the phone ) down low and plugged it in to the Rotel phono amp section . The music came through loud and clear of course , but as I pressed pause on the radio app ( to stop the music and allow me to listen for the hum ) ....there was none ? The hum had gone ? As soon as I unplugged the jack from the headphone skt on the phone , it came back in force ....but for the time it was connected to the phone , there was no hum ? What does this mean Jan ?
@CaptainDarrick I‘m still pretty sure it’s a ground issue. You can try adding a ground wire to your turntable. That should help eliminate the hum. Here’s a good explanation: www.soundswow.com/ground-turntable-without-ground-wire/
Ground in this case doesn’t mean earth by the way. The ground wire just brings ground levels from both devices to the same level. If they are at different levels for some reason, you naturally get lots of noise in the signal.
The relays opened up after the amp was running for a while. I think that’s what the owner meant with the fault description they gave me. It wasn’t technically going into protection (as in the LED going red and the protection triggering the relays), it would just go silent after a while.
My guess would be a dirty/corroded input selector switch. But as I said in the video, there's quite a few potentiometers and switches the signal travels through before reaching the amplification stage. All of those might need cleaning. Usually a bit of contact cleaner resolves the issues at least temporarily.
Basically, yes. I also meant that later receivers/amps often had digital channel switches and all kinds of displays (that were rather prone to failure). This is just a very down to earth class A/B analog amplifier without any fancy shenanigans. Lovely device. :)
I have the 530ES. Same problems with the switches and pots, all scratchy. Also there is a significant loss in high frequencies. I think it needs a good recap on the preamp/tone control stages.
I found that cleaning the switches and pots already improved the high end quite a bit in this particular one. Recapping with good brand caps is always a good idea for equipment that is a couple of decades old in my opinion though. :)
@@JanBeta I agree. Your video will be a good guide on how to disassemble mine when I start the TLC. They look identical in appearance, maybe there is a power difference. Thank you.
Maalesef aynı sorunları ben de yaşadım. Yağsız kontak temizleyici kullandım. Volum potansiyometresi idare edemez duruma gelince değiştirmek istedim ve tabii ki bulamadım. Sonunda Çin den 2x4 pinli benzer pot alarak monte ettim. STK yandı. Yine orijinal bulamadım replika stk3152 taktım. Röleler değişti. Kapasitörlerden biri bozulunca DC offset problemi oldu ve tiz hoparlör yandı. Şimdi kötüleşen kapasitörleri değiştirmekle meşgulum. Artık ülkemizde bu tür ürünleri satın almak çok zor. Onun için sonuna kadar uğraşıyorum çünkü tamir ettirmek de pahalı. Bir amatör olarak bunları yaparken zorlanıyorum ama değer.
@@ynahit3746 Siz çok dert yaşamışsınız gerçekten. Benim de korkum STK'nın arızalanması. DC offset işi de fenaymış, hoparlörlerin cross over devrelerini geçemez diye düşünürdüm.
@@borayurt66 STK yı korumak için kasanın üzerine STK yı hizalamaya çalışarak 12 cm lik PC kasa fanı yerleştirebilirsiniz. 12 voltluk fan 5 voltluk cep telefonu şarj aleti ile de çalışıyor. Hızlı dönmesi gerekmez sıcak havayı çeksin yeter. Unutmadan cızırtıya sebep olan elemanlardan bir tanesi de MUTE tuşu.
I've just been gifted a nice 90s Technics Amp/tape deck with separate CD and Vinyl decks after years of saying I don't need a 'fancy' stereo and I love it! It might need some work in future so good to get some tips, cheers!
I tried that but wasn't able to make it work. There was still too much wiggle in the switch housing for my taste. They are going to work and hold together without the glue though, it was just a preventative measure. :)
@@JanBeta In many cases, plastic degrades and breaks down over time, so gluing it together after a good wash and cleaning is the most rational method. It works well and that's the main thing. Good work worthy of respect. Taking off my hat!