How to repair Sansui AU-G77XII Integrated Stereo Amplifier No Output D-lab Electronics
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- Опубліковано 6 жов 2024
- This amp arrived D-lab in need of repair. Initially, I did not want to take it. Then I was thinking of past memories of repairing these in the Dorm USAF. I knew that I could help the guy out. He bought it new and had a love connection, so I caved. I love repairing older electronics, especially when it makes a difference in someones life. Its a hobby of love, my friends. I dont make much $$, however am blessed in gratification. Hopefully this info is of value to you, my friends. TD
I bought my Sansui AU-G77XII in 1989 and I still have it. It works like a champ, haven't had any problems and I use it every day.
I have one also that I bought new back about that same time. I will never sell it. It has a beautiful sound ,fantastic dynamic range.
That Sansuich is on the top of the food chain compared to the other vintage Not much out there that commands a higher price than their models from beginning to end. Respect!
San sewage
When someone that knows nothing about electronics sees the complexity of these things it really is amazing that a team of designers, manufacturers,
engineers, sales people can deliver a product like this to my door and all I have to do is push a couple buttons and there's music. It really is a technological wonder that in this modern world doesn't even raise an eyebrow anymore.
I'M still trying to figure out how RADIOS work (lol) and I am 86 years of age!
Really appreciate your intelligent,thorough approach and clear explanations,thanks.
That bottom panel was a godsend. Until you've had to pull a board in a piece of gear like this, you just don't know what a pain it is. Thanks for another great vid, Terry.
That's why I don't work on newer stuff. Plus the quality is pretty horrid.
ចំរៀងថៃ
Hey man I watch all your vids! Keep it cool. I’m here just watching repairs because my carver amp is being fixed by hi teck audio in WA state and I’m hoping for the best.
My first stereo purchase was a sansui au-5900 integrated amp....great little setup, used it for many years and lost it in a bad house deal....D- Lab, you rock
I went through a whole lot of solder joint checking on an Onkyo amp that would not click, even shorted out the final transistor and had to buy another set! After all that, it turned out that the relay was bad. I got it working in the end, and I learned a lot in the process, so it was a win.
The main idea of SANSUI desiners SUSUMU TANAKA and SUSUMU TAKAHASHI was to minimaze TIMD ( transient intermodulation disdortions) in audio power amplifiers which was the main cause of harsh "transistor sound". They did it by using patented DD/DC differential stage in input stage of power amplifier and gettin high SLEW RATE of output signal. They followed and developed the ideas of MATTI OTALA - ther co-member of AES (AUDIO ENGINEERING SOCIETY ) firstly presented in 1971. Result was achived and natural sound from vinil LP and tape decks started giving a lot of joy to sensitive ears by means of bipolar transistors and not only with tubes . Idea also was developed by ROBERT CORDELL from BELL labs . He used power MOSFET"s and write a wonderful book " Designing AUDIO POWER AMPLIFIERS " in 2011
Very interesting indeed!
@@alexanderemul4559 Thank You !
Thank you Sir. I am an electronic technician and i do those repairs everyday. Today i find a lot of crap like Denon Amplifiers that have all the power supply components that become very hot, all in the same area one beside each other so the amp becomes so hot that those components unsolder by themselve. Real bad design. No radiator on the 15 and -15 volts TO-220 transistors, crap. So i modifie, i put radiators on those and sometimes i switch components place so no more heat but when i switch them i have to watch too for ocillation. But what i mean is that today's amplifiers are crap. And you are right Sir we can not either open the cover under the amp. That sucks. Good old time. Thank's for your video, very professionnal. I'll keep following you.
Why would you say Sansui is crap ? I worked for them back in the mid eighties, and have always found them to be exceptional audio gear until the last few years before their demise. I currently repair and restore vintage audio gear for collectors, and every once in a while, one of my customers will slide a beautiful old Sansui across my bench for me to restore. I don't care what Pioneer, Marantz, Sony, or Technics is already on the bench, it gets pushed aside so I can give some love to the Sansui. I know you were just trying to be funny, so just tell us more jokes about how Marantz were good amps. ;O)
If you want to hear one of the best stereo receivers ever produced, try to get your hands on a Sansui "Model Eight", now that is an exceptional piece of audio gear.
Take care, and have a great day.
I know they're not your favorite, but I feel like I learn a lot from each of your solid state repairs. You remind me of things that I thought I'd long forgotten when you troubleshoot. For that, I wish you and D-Lab a hearty thanks!
Thanks for giving your time and knowledge its awesome that people like yourself give their time and expertise to show others that are just learning and want to improve as technicians so thankyou so much for your time fantastic!
One of the best UA-cam repair demo channel, show us the logic of each step with practical analysis and repair.
Terry
Thank you for generously sharing your wisdom. Much as I am addicted to collecting these vintage beasts of sound I am so ignorant of how they work and of course how to repair. To see you in action is like watching a great artist perform at the zenith of their game. If there's an Emmy for Electronic repair teaching you would certainly get my nomination. You sir are bloody marvellous to watch as you take us through the steps. Many thanks.
The older sansui equipment was a lot better made than it is in this example this was in the era where there equipment really went down hill i own a au719 au919 tu 719 and assorted other sansui of the vintage era good job terry 👏
Having been through a number of Marantz 22xx receivers & Sansui G/AU units, I much prefer the Sansui. Other than the glue issues, they were fairly easy to diagnose/fix. The Marantz units packed the boards in so tight it was a pain to work on, & they seemed to have more heat damage/stress. Sound-wise, I like them both.
Hey fellow USAF guy, I too did time in the Air Force, and I remember "audio heads" guys who would suggest various gear and tell you what was good and what was stuff to avoid. When I was stationed in RAF Upper Heyford, we had a small but good audio shop with all kinds of gear, some high quality stuff, I did buy a Carver 1.5T amp and a Carver preamp. and had to go with those British made Kef speakers, boy some great sounds. Those were the days....Thanks for showing this video. God bless.
When you start finding questionable solder connections it is a good thing to retouch all connections on the board while adding a little fresh solder. I have spent half a lifetime doing just that. Sometimes the wave soldering process at the factory was not good or certain parts had "dirty" pins that never soldered properly to begin with. What you did was good. A lot of older equipment had soldering problems from the factory that developed bad connections over time. Add excessive heat or vibration to the equation and you have a recipe for failure. Good job. Brought back old memories.
This is a great amp! Looking on Ebay they are priced at $900 and up. Def worth the fix/ restore.
Simply a simplistic solid state Sansui service serving seers senses.
Love this channel with the real time step by step debug procedures and your sense of humor!
hughmöör ? thöse öther geiss... the one with the roof room wood floor and few? amps ön a weihäerr v? v
It's not often I sit an watch a video ALL the way through. Great patience and camera work too!
My Sansui was starting to do this and I put it up. Should have checked here first.
Great video, thanks for covering all the potential issues with the protect fault.
Thanks d lab for posting all-ways learn.
Love your content, no nonsense attitude and sense of humour - wish I had your knowledge and experience but you help me improve my general electronic and fault finding skills.
´Rich böyy ^^
thanks again D-Lab, you did it again. warm regards from Australia
Great job. Love sansuiage 😊. Mine one is 35 years old but still kicking hard. Superb!
Very nice Sansui amplifier, very nice repair and very nice way to explain it. Thank you!!
Back in the 70s when I started being a "solder jock", we called em' San-Suckies! All the brands we had to work on had nicknames. You have the gift of not giving up. Thanxz
Collins
75a4
36 thumbs down...some body has a troll? Lol. I started with old 1950's Arvin, Hunt black and white televisions, whitney amps and fm tuners...until one morning B+ discharge went wrong..my skull print is covered by plaster of paris patch on living room wall..ha!.
Respect those 1x and 3x hv tubes..
My tv repair cyclopedia book set from 1958 look like new..color pictures were just coming in the market...
Great patience you have.
..🙂
you explain so good man . I'm learning a lot. and I'm Dutch so that's a big compliment
Yes I just did a repair on a JVC A-X1 amplifier which does not have a removable bottom panel !!!
A whole lot of unscrewing and deconstruction for just one bad electrolytic ! great fun.
Very informative for those of us early in the hobby. Thanks!
I currently own this exact model, that you just repaired. Knock on wood, it hasn't given me any issues yet and hopefully it never does...lol but if it does...I will know just what to look for to repair it. Thanks you so much for making this video! 👍
Hi Terry-second !
It is nice to watch you doing a repair sober!, it is great to listen to you not
slurring your words
You teach great stuff !
Thanks once again
I'm never bored watching those videos 👌
This is what my JC Penney MCS receiver from the early 80s does. It takes more than 10 minutes before it powers on. I have a modern surround sound receiver my buddy gave me but I'm still using my old piece of junk receiver. Thanks for the tips.
Gentle man. Good job. God smile with cup of 🍵. Like the style of sharing . Stay blessed sir.
I bought a sansui stereo system years ago don’t remember model but I had it hooked up to infinity SM-155 speakers and wow could that system rock unfortunately a few years later I traded the system for a car. Great video
I love the repairs to this SS equipment. Not much available anywhere. Many of my guitar amps are tube types but I have several Transistor models and many power amps. This helps me troubleshoot and often repair my stuff that otherwise ends up in a landfill.
You are very laborious Mister D-lab ! Congratulations ! Keep up the good work !
If there were a Nielson rating on electronic fix-it videos, yours would have a commanding lead ---you know what you're doing, you show confidence in your techniques (like arranging the leads on the speaker relay to fit the pcb), and I feel like I might have a chance on tracing down my driver board amp's problems on my AU-7700. I just got it and one channel works wonderfully; the other is shooting craps -- extremely low output. This is my first Sansui and whoever had it before me took out parts and unsoldered wires to this board. At least I have a schematic but my test equipment is very few: a DOM with a diode checker. I'm over my head but i'll learn. I've heard this AU-7700 is definitely worth the patience and learned skill. Thanks again for these great videos!
very interesting video - I have a Sansui Z-9000 receiver that i bought back in the early 80's that did the same thing a short time after i bought it - got it fixed under warranty.
I grew up with a Marantz 4300. I really wish I still had it. We do have another one in the family that I will restore with your help.
Good work 👍.
It works great the old sansui.❤️
Thanks, Dear-lab! You kept me soldering and saved my Amp!
its Been years since iv seen a Sansui amp.......great video keep it up!
I still have this kind of Amp, sane problem,,,BUT i LOVE THIS amp, HOPE will work some day....Thanks
I have a couple of amps that are missing one channel and they have resisted all my attempts to fix them. I have checked all of the components, but didn't think to check the solder joints because at first glance they looked good (bright and shiny). I am embarrassed that I didn't check the joints because for years I worked on instruments that were notorious for having cold solder joints. I will have a much closer look at the solder joints. Thanks for the great tip!
All your video and work was wonderful but the best part was the last...A Great cup of Wine !
Good job! one of my worst nightmares is running into multiple cascade failures due to poor solder connections; relay output protection makes a big difference when it comes to saving components.
looks very interesting, Integrated Stereo Amplifier with great construction worth repairing and putting it right
Hi, I sincerely invite you to come to my stereo shop. The following is the address of my shop
hiendchina .com
Excellent repair and diagnostics. Thank you
Great for vídeo,thanks D-Lab!
Mr. D-Lab is the last of his kind. So sad to think that HIFi stereos have become extinct. I never thought it would happen and what really get my goat is that the mini disc players had incredible sound quality but we ended up with the mp3 players. People wanted quantity over quality. I just don't understand how so many people gave up on home stereo systems. I suppose the advent of the internet killed HIFi stereo systems.
There are still many of us that collect and use vintage stereos from the golden age of stereos- the 70's and 80's. Sales prices are way up. I am a retired tech, and maintain all my own gear.
True, there aren't that many of us left, and techs like us are highly sought after. I won't work on anything made in the last 25 years because they are largely parts unavailable & unrepairable, disposable gear.
Good vid with good circuit board hints. Makes me want to take a more in-depth & intense look at my old RS Pro-2004 scanners board.
Great job Sir. You deserve much more than a cup of wine. Bravo☺
Crapsui was also a popular nickname! But I still love all of mine!!
Fantastic Terry, thank you. We need another amp build from scratch. Thanks again!
In 1985 at the PX in furth Germany I got the AUd11-2. At 130 watts very clean. Then I got the polk sda-2s and the harmon cardons cassette player and Onkyo turntable with an ortofon mc. Paid about 1,5oo.oo still have them today.
I love the San sewage that was funny as,hell ,I no when I.was in the milatary all the guys in Germany bought a lot of stereo equiptment,I bought a lot of camera equipment my self ,they had a good size stereo shop on the base ,the selection.was amazing ,I bet you a lot of your friends change brands ,after that can sewage crack .
One thing I love about Tubes Less Parts.
COOL! Nice repair, great glass of wine.
great video. I also very much appreciate the message in the description. Humility is becoming increasingly rare in our world these days, but I do believe you have it. Thanks for the great video, as it taught me about the hobby I'm very slowly learning about. Keep up the good work, my friend. :)
Your videos always thrill me from the first second I hear a unique intro sound. Boy, this roots reggae bass line was stuck in my head for the rest of the day :D Thanks for sharing your awesome knowledge with us!
Suggestion on the rosin removal, especially the old stuff. Try Acetone! Takes it right off and does not harm the PCB or solder mask. However be careful around plastics like capacitors. I will eat into plastic.
Hey i like how you explain the process...to bad i didnt had this 20 yrs ago...
You must use an Ac filament Bulb 80w-100w in series with the Ac plug , act as a short-circuit protection it will light up so bright if a short is present..
sansewage. love it. do love the older SS gear though mate.
Good job D-Lab! Thanks for the tips.
after such a great job, you can ring that bell many times.
I recommend using a dim bulb tester, may save the day.
Seen your E6000! That stuff is almost a cure all! Thanks for the informative videos. Great work!!!!
Nice repair But to put away those worries while plugging it to AC mains just put a series filament bulb or halogen = 60w/80w -110v - 220v as a fuse to avoid big bang if bulb glows bright indicates shorted, if it glows low means OK; thanks for sharing
Don't let the silly commenters disparage your wine. They're just jealous they don't have a 1/100th of your knowledge and personality!
The only thing I did not like was the powering on of the amplifer , without a variac, or even a Light bulb limiter. This would save it from a short on power up.
Congrats!... I enjoy the end with a cup of wine... greetings from Lima-Peru.
i total agree with your topology
Excellent video. boss
I'm on slowly restoring my late father's sansui stack system, speakers aswell. The original amp an A 80 blew up so I managed to track down an AU D7. As I doubt I will get the A 80 repaired as many "hifi repair" are like no wouldn't bother.
You just don't get the volume and clarity, I ain't saying it's the best but damn well will knocks the spots of a few modern equilvants and factor it's age ....
Sansewage! love it...
Amazingly clear and thoroughly explained tutorial sir! Thank you for taking the time to create it. I’ve been searching for a stereo dummy load test device like the custom one you made, but I don’t see anything similar available. Do you know of anything on the market that’s like it?
I stupidly junked an AU317 mk2 many years ago . I wish I hadn't because it was 80 W per channel , sounded great . It all seemed far to complicated when I was younger , and past it's useful life . Compared to equipment of today , it would have been an easy to service item . It wasn't sewage at all . I'm sure we've all got rid of so much cool old gear , that we should of kept for another 34 years until it was desirable again . My worst being a 60's VOX AC30 for a few quid , back in the late 80's .
I agree man, At one time I had a beautiful Marantz 2275 in the wood cabinet with a pair of JBL-100's. Would love to have that set again. TD
Wonderful! How I wish I had your knowledge :-)
Excellent video.
Hi. Nice channel I need to view all your videos. I don't know how many of those AV amps I've repaired that have the fractures on the solder pads. Both the output transistors, and higher current components like resistors. Heat cool cycles until they fail. Thanks and take care sir.
Terry you should try lacquer thinner to clean the flux from the board. It even cleans away old flux.
That intro was pertty dang cool Terry lol great job.
Bravo!!!
Well explained issue, thanks.
Obrigado from Portugal
this type of amplifire are all power i like old unites more than the new ones
Great job!
Hi Terry, another great video - thank you. Would you consider doing a video on the stereo dummy load wattmeter and detail how you built it? I would love to have one on my bench!
Back in the day when I was a bench tech nine times out of ten the problem was leaky differential amp in the front part of the power amp. I replaced thousands of these transistors on just about every Japanese brand. Pretty much every manufacture recommended changing the diff pair on both channels if any DC was present in the output. Must be a matched pair to actually work properly or you'll get extra noise in the output...
Tom Messina I've done that before too but on a Yamaha P2200 to compensate for lack of DC offset adjustment trimmer. I put in a socket and two KSA992s, changing one for lowest offset. What do you recommend as a part for a new diff pair? I know it's best to use an IC
I have often successfully replaced the diff pair with two matched discretes.(I used a Sanwa analog vom that could measure hFE at several values of Ic to match them )
Well, Most importantly I was today's years old when I learned how to pronounce Sansui I guess. Always figured it was SAN-SWHY lol
Great video and it's explained in layman's language! I'll buy you a gallon of the finest port wine if you can go over four old Harman Kardons I have sitting here!
Oh, Man, These used to be common in the UK, people don't seem to understand how awesome they are, Still!... I've been looking for an amp for a media centre I'm building for my movie collection with driven by Kodi. Think I'll give eBay another look, later.
Great job ! Just wondered why you didn't just use a signal generator for the inputs...
Excellent!