Hello, can you show us where are you adjusting the tension from?
@user-xw2tj1kn1f3 күн бұрын
Great!! Thank you. this helped me open the D-105u I just bought! 🔥❤️🔥
@whatcouldgowrong79143 күн бұрын
Be very careful with the D105u and ensure you put the connectors back in the correct spots otherwise bad things happen
@LuckyX210 күн бұрын
Thank you so much for all your effort designing this and then giving it back to the community :)
@whatcouldgowrong791410 күн бұрын
Glad I could give something back 🙏🙂
@nothingelse152012 күн бұрын
Awesome! Wish there was something like this on the market
@whatcouldgowrong791412 күн бұрын
Il discussing with some people about doing a proper PCB. Still early days :)
@PeterMilanovski12 күн бұрын
Wow! Who would have thought that this was that good? Although I shouldn't have been surprised, when it comes to audio, there isn't anything that Yamaha hasn't done! Everything from playback to music production! I came across a Yamaha CD recorder with built in HDD by accident and I wanted to know why it was so expensive! It looked like a normal CD player! After searching for it specifically I found it being sold for a couple of hundred dollars and bought it, my son has one too and it's the most amazing CD player/recorder that I have ever seen, you can connect it to a screen for the music details, you can use its internal DAC for external components..... And it has a level metre which is in my opinion missing from the majority of CD players! They are going to have to pry it from my cold dead hands after I have died to get it! I'm considering having it buried with me LoL! The model number is CDR-HD1300. There is two different models, one has a larger user replaceable HDD than the other.... Another nice touch! Load all your favourite CDs or tracks into the HDD and let it play all week long! It's kinda like the DVD recorders with HDD.... If you have ever used one, editting out TV commercials or songs from RAGE that you don't like is so easy! I have a pioneer and a Sony DVD/hdd recorder, they run the exact same operating system and both are great and being sold for next to nothing! All highly recommend! Cl Check them out!
@PeterMilanovski12 күн бұрын
When it comes to finding what's causing the noise floor, a single tracer is your friend, especially if it has the RF mode where you can hold the probe above individual components and hear what's going on... Paul Carlson of the Mr Carlson's Lab channel showed how a bad carbon resistor was adding noise (sounded like a thunderstorm was going on inside the resistor). Sure you could have found it via an oscilloscope but the signal tracer was so much faster and easier to use since you don't have to keep looking up at a screen! I personally don't have one but I have always wanted one since I first saw one being used! It's a pity that Heathkit doesn't make the kit anymore! Or at least I think that they don't, haven't checked their website in ages, they are re- making their digital clock though.... Every workbench should have one!
@whatcouldgowrong791412 күн бұрын
Never had any luck with any of my tools as my those headphones are so sensitive that it is generally beyond the noise floor of my oscilloscope etc. That said I’m quite sure it’s normal for the era and minimal. Never heard a preamp or integrated preamp that had an SNR high enough from the 70s and 80s except maybe the Sansui Alpha’s. Probably some Yamahas also that would pull it off knowing how well they usually measure…
@PeterMilanovski11 күн бұрын
@@whatcouldgowrong7914 on the topic of the signal tracer, you can gain a similar effect using an old cassette deck head, using the playback function, it's pre amp is pretty high gain, with the head removed and attached to a piece of dowl, you can make a probe that simply by placing it near a component, you can hear what is going on inside... I'm not sure if it will work as well as a proper signal tracer like the one's built in the 1940's in America, Mr Carlson's Lab KZbin channel has built his own modern day version of it, he has videos of the build plus all the details behind the patreon wall.... It's an indispensable tool that will make problem solving so much earlier and faster. It's a whole other world going on inside each and every single component but we unfortunately can't hear it without help..... I don't personally have one yet even though I have wanted one for years, I will either make one by cascading a few opamps or if I'm lucky enough and have the money, I would get an eiko or Heathkit that has the RF signal tracer ability and have it delivered from the US! It's a bucket list item for me!
@PeterMilanovski12 күн бұрын
Great job! That puffer jacket screams Melbourne! Good to see someone putting in so much effort who possibly lives local to me..... I think that the benchmark for amplifier restoration is held by X-ray Tony B, he also does a talk over while he's soldering which works better than just listening to an extraction fan or at least that's what it sounded like to me! Besides that! And apart from installing the new diodes which I probably would have sat them a little bit higher from the PCB to give them a little breathing room but the original one's didn't appear to be generating enough heat to burn the PCB so I guess that it's not important.... I really have nothing to complain about! Going up in the voltage rating for the capacitors was definitely a good call! I especially like to go up in capacitor voltage rating if they are located next to or above any heat source, the higher voltage rating is the equivalent of higher temperature rating and helps keep those capacitors live longer.... Which is always a positive for a proper restoration.... I'm looking forward to watching more!
@lovejahandlive891215 күн бұрын
I have the same power amp and it needs repairing, can I ask what happened to yours that it needed repairing?
@whatcouldgowrong791415 күн бұрын
I believe someone tried to adjust the bias without setting the correct impedance on the back per the service manual procedure
@focushub857119 күн бұрын
Thank you
@adaboy4z20 күн бұрын
I almost pushed the buy button on one of these as it wasn't expensive but glad I found your video first.
@professorxexplainsyouruniv843124 күн бұрын
Thz man! I'm searching what is AST and I also have ast A10 amp. You help me a lot.
@timomy824 күн бұрын
Well done stick to your guns only you need to be happy, no compromises unless you so desire. Thanks for sharing.
@horaciorecalde168925 күн бұрын
Excelente videos. Mirè los 5 y estan muy buenos. Hace muy poco, comprè un 5650 y tiene un sonido muy bueno. En los costados tiene una madera con vinilo que no me gusta y quiero preguntarte, que madera usaste? Se vè muy linda y el color tambièn.Muchas gracias...
@whatcouldgowrong791425 күн бұрын
Im not sure what the wood is sorry as I got it years ago but it was from the hardware store and some sort of laminate. Not an exotic wood as it wasn’t expensive :)
@horaciorecalde168925 күн бұрын
@@whatcouldgowrong7914 muchas gracias por tu atención. Esperamos vídeos nuevos.
@paulstubbs767825 күн бұрын
Interesting your comments about replacing all the transistors, I have a Toshiba SC330 amp kind of on the bench, having fun finding suitable transistors, one of the channels input stage - long tailed pair was starting to 'go', it would cause the amps output to spike up to the full supply rail, took out my test speaker, which surprised me as the spikes were quite narrow. So yes, old transistors are a problem.
@whatcouldgowrong791425 күн бұрын
They seem to become more problematic with age, I don’t recall it being such an issue a decade ago, the HK330B was really bad also
@mattiamanc25 күн бұрын
I find it surprising that it has a noticeable noise floor. I restored a few of the Sony V-FETS (about5-6 TA-5650, 2 TA-4650, a TA-8650 and a TA-F7), nowhere near your level (apart from killer diodes, recap and the usual for these I tend to leave semiconductors alone), and the only one that I found was noisy (hiss) was the TA-8650 (from a noisy pre-amp section, but it is likely because it uses very early ICs). The only thing that I noticed was that the TA-5650 and 4650 tend to buzz a lot if you use noisy inputs (desktop computers, mobile phones) because they are very sensitive to EMI. Not sure whether the noise floor you describe is a hiss or a buzzing noise, but maybe worth checking whether it has something to do with EMI.
@whatcouldgowrong791425 күн бұрын
The headphones I used are very very sensitive and pick these things up easily, it’s not an issue for my speakers or electrostats but definitely present. Not unusual for a 70s or 80s preamp-amplifier either. It could be the jfets but not as easy to substitute.
@bst873325 күн бұрын
Just love the transformer(s)/headphones idea. Brilliant!
@bpalpha25 күн бұрын
Thanks man. Handsome unit there.
@Roudaki67725 күн бұрын
I own several of the VFET family, in fact one of the 4650 since brand new. The 4650 has always been the sweetspot of the range. I own a bunch of vintage items from Sony’s golden era. If you ever run across a TA-2244 or a more widely available TAE-86 or TAE-88 you will find preamps that rival modern preamps after some minor restoration.
@whatcouldgowrong791425 күн бұрын
I shall keep an eye out for them!
@petermaurer32325 күн бұрын
If you want to do a full resto, it's no one's business to question as to why. I've followed all 5 parts and great outcome. Looking forward to future projects.
@adaboy4z25 күн бұрын
Been waiting on this video!! Parts list!! Thanks.
@whatcouldgowrong791425 күн бұрын
It’s in the video :)
@AN-ce1nd28 күн бұрын
Yeah but here’s the fact. More components in line with the inputs, added electronic distortion. Pretty but a complete failure. $2.37 tops and that includes shipping.
@whatcouldgowrong791426 күн бұрын
Well it measures better than it did before I started so.....
@ec167528 күн бұрын
By any chance you have the part number of the rectifier replaced? And the heat sink used on those 2 transistors on driver board? Nice video, very informative. Thx.
@whatcouldgowrong791426 күн бұрын
I believe I used a KBL type 4A rectifier. The important part is to cool it properly as they run hot. Didn't touch the other transistors other than adding a heatsink
@ec167524 күн бұрын
@@whatcouldgowrong7914 thx for your reply. Chasing my high dc offset at the left channel now. Will look into it more and the heat sink tip.
@whatcouldgowrong791424 күн бұрын
@@ec1675 How high is the DC offset?
@ec167524 күн бұрын
@@whatcouldgowrong7914 it was around 190 mv at left, 24 mv at right (ok). So I found C7109 (47uf) in 1st differential on driver board totally off by a lot. Like at 300nf. So I replaced with a new one hoping to fix the issue. But instead it goes up even higher to 360 mv. I post my issue in some forum here but got no response. Totally desperately need some guidance. Probably will continue to pull and test the cap on the driver board to see.
@whatcouldgowrong791424 күн бұрын
@@ec1675 I haven’t looked at the schematics for a long tome but check the gain of the differential pair. If there is a mismatch, it will create significant offset :)
@tarzancountrydance9534Ай бұрын
Hi what are the new tubes you put as a replacement? And why did you replace them?
@whatcouldgowrong7914Ай бұрын
6CG7 Electro Harmonix tubes. I changed them because I do not have a tube tester and removing the tubes is not simple / the holder is fragile and cannot be dismantled many times before breaking completely.
@phuocnguyen8774Ай бұрын
I can make my own electrostatic headphones. But what I can't do is the amplifier. I am not an electronics person. That hindered my passion.
@batmandestroys1978Ай бұрын
You are a modest genius!
@whatcouldgowrong7914Ай бұрын
Many thanks!
@maheensulaiman1410Ай бұрын
Hi .Iam a subscriber of your channel . Your video is amazing. I have a same cd player but the previous version. The cd is not spinning. Pick up is new .it spins sometime but no TOC in display. Eject ,play ,stop and pause micro switches do only the eject function . Any set up to ne done with transport mechanismAny advise could be appreciated.Thanks
@whatcouldgowrong7914Ай бұрын
Check to see if the lens moves up and down first which means it’s starting the detect process before spinning up
@RoyFJ65Ай бұрын
Like you I have collected a bunch of amplifiers, all from Yamaha including a P2200, PC2002m, M50 and a MX-1. Can't get myself to get rid of any of them.😄
@whatcouldgowrong791429 күн бұрын
Yamaha MX-1 is on my radar!
@martinbutirich4680Ай бұрын
Do you work on these for customers?
@whatcouldgowrong7914Ай бұрын
Occasionally do work for people but the magnitude of these restorations are beyond any normal customer’s budget and I do them as personal challenges / statement pieces for my collection
@jtfoto1Ай бұрын
Great idea for the speaker terminals but I have to admit I'am not a fan of the deviders.
@whatcouldgowrong7914Ай бұрын
Banana plugs can bend when pressed against something and short on each other. Audio ones usually aren’t insulated
@janinehugo8988Ай бұрын
I had one of these. Bought it brand new in 1983. It is part of a stack, with the record player on the bottom, amp, radio and tape deck units on top, with everything playing through the amp where the speakers attached. Was a fantastic unit
@mistermac56Ай бұрын
Excellent work. The silicone pads are so much better for thermal than mica wafers and heat sink grease for the V-FETs.
@whatcouldgowrong7914Ай бұрын
Yup I hate thermal paste!
@iceberg789Ай бұрын
except bare boards and cabinets everything got changed. 🤔
@whatcouldgowrong7914Ай бұрын
Its a 50yr old amplifier… the boards are original, everything was changed based on ensuring it keeps working for another 50yrs
@tinsoesoesoe1346Ай бұрын
Please give me some circuit diagrams.
@whatcouldgowrong7914Ай бұрын
All the documentation is on HIFI engine / google :)
@BaskaranBaskaraАй бұрын
Rummy circle vilambaram podaathadaa they..., paiyaa
@garygranato9164Ай бұрын
noob question but why would he change out good components ? particularly the resistors ?
@whatcouldgowrong7914Ай бұрын
Good is debatable these days, amplifier is almost 50yrs old and everything degrades. Capacitors are mostly fine still, transistors have drifted too much and needed to be changed / some are known to be problematic. The other resistors, some were a service bulletin, some had failed and the others i changed were in the signal path with high modern high precision resistors to try and improve thermal noise. Was it working before I started, sure. But as I said you get one shot with the VFETs and if something fails absolutely damages them, the amplifier becomes useless unfortunately.
@markwroblewski6500Ай бұрын
Great idea to include 3D Printing into the project.Shows your expertise in many fields.Out of curiosity -What printer did you use?Thanks in advance.
@whatcouldgowrong7914Ай бұрын
Snapmaker Artisan, there are some videos in my channel if you want to see more on it :)
@repsychАй бұрын
Thanks; what is the solution that you use in the ultrasonic cleaning machine?
@whatcouldgowrong7914Ай бұрын
Ambersil ultrasonic cleaner with some IPA mixed in :)
@markwroblewski6500Ай бұрын
Love your perfectionist approach.2 questions - What's the make of the green soldering iron you're are using so skilfully?As well you've mentioned pairing/coupling of transistors.How would you pair NPN/PNP output ones in a Class 'A' power amplifier[Krell for example].Many thanks in advance.
@whatcouldgowrong7914Ай бұрын
It’s a Thermaltronics TMT-9000 inductive soldering iron, had it for a decade :) Inductive soldering irons will change your life, no waiting for joints to heat up / turning up or adjusting temperature etc
@ZoomerlandАй бұрын
These things were big, ugly, stinky, dusty, and I don't miss my massive Sony receiver.
@markwroblewski6500Ай бұрын
Nice clean job.What's the brand of the suction pump you are using.Looks very effective.
@whatcouldgowrong7914Ай бұрын
It is very good, its a GOOT solder sucker, had it for over a decade. It has its bad days but its never has anything replaced on it and should probably get a new one. Only problem is it’s not single handed use but I just use my hip to reload it
@LuizMoraes-fn5irАй бұрын
Fantastic work. Greetings from Brazil.
@musicscratchponyАй бұрын
Hello! Could you please share a link to the service bulletin you are referring to in the video? The one that I found doesn't have the info about the necessary resistors' parameters for replacement. I believe they are different for each grade of V-FETs? That's why I would really appreciate you sharing the link! I'm starting restoration of my 4650 and will follow your videos thoroughly. Keep it up and good luck!
@whatcouldgowrong7914Ай бұрын
There are 2 service bulletins, this is the one for the resistors and bias change. Just take it slow and leave out the vfets until you confirm all the voltages and do the service bulletins. The other bulletin covers testing the VFETs and setting the bias voltage to maximum before reinstalling. Link www.robuust.nl/~maarten/forum/Sony%20VFET%20bulletin%20[MAE].pdf
@musicscratchponyАй бұрын
@@whatcouldgowrong7914 Thank you very much, I appreciate it! By any chance, do you know if any components should be replaced in the TAN-8550? Or is there a same kind of a note for it? According to my research, it all goes down to replacing the VD1221's and recapping + using the correct resistors to match the grade of V-FETs according to the regular manual. Seems kinda strange to me that 4650 and others have some changes and have to have their resistors replaced for the bigger value and the 8550 seemingly does not.
@whatcouldgowrong7914Ай бұрын
@@musicscratchpony I don’t have any experience with the 8550 (yet) but im sure some people have experience on audiokarma. General practice for me is to replace any adjustment pots and those double diodes at a bare minimum. But if you want to be really really sure the whole unit should be gone through testing transistors, capacitors etc. It used to just be recapping vintage gear but we’re approaching 50yrs old now and transistors are becoming a big problem also with age. I believe the resistor changes were in relation to the bias change and a design modification. It was just a value change but I generally use higher power resistors because technology has shrunk them drastically
@MrJohnBosАй бұрын
Beautiful restoration, the amplifier is stunning indeed. Better than new. I think you could definitely cut way down on the time lapse. I'd much rather see and hear your thoughts on why you are doing what you are doing. Other than that, I loved the entire series on this amp, well done.
@johndcosta1259Ай бұрын
Impressive work. Can you please share the name of the glue remover you use?
@whatcouldgowrong7914Ай бұрын
Toluene or carby / throttle body cleaner seems to do the job but use it sparingly as it can attack plastics etc
@johndcosta1259Ай бұрын
@@whatcouldgowrong7914 thank you very much for sharing the information. I have a Sansui AU-717 and Sansui 5050 receiver which I plan to restore soon. Both of those units have that corrosive glue on the board.
@whatcouldgowrong7914Ай бұрын
@@johndcosta1259 best to dab it on the glue and let it sit, the glue should turn to a gel eventually once you break the top layer.
@savvassidiropoulos5952Ай бұрын
Those time lapses are not doing justice to the work. I understand the reasoning behind wanting shorter videos, but I don't mind long good ones. Perhaps showing important details for each section in real time? Or including chapter marks so people can jump these sections if they are bored with details? Anyway, it was my first time watching your work and I need to offer my compliments to a job well done.
@whatcouldgowrong7914Ай бұрын
I agree, I’ll ponder how I can strike a better balance, split more videos or something, unfortunately I can only go off KZbin analytics and long videos seem less popular. Thanks 🙏
@RegiPavanАй бұрын
Absolutely gorgeous restoration
@whatcouldgowrong7914Ай бұрын
Thanks! 🙂
@ukrainehamradioАй бұрын
Great job!
@kirtanajaya1782Ай бұрын
Hello, i'm also trying to convert my srd7 to be able to drive pro bias stax headphones so could you please make a tutorial or tips as to how you've done it, thanks!
@whatcouldgowrong7914Ай бұрын
Sure, my original SRD-7 was based on STAX’s original bias design but I actually have a video coming soon for what is hopefully my final design based on current technology. Ill add in some video the original one I built :)