Hi fi repairs

[lowell]

This is mostly a question for Enzo, JM, Markus, Steve, RG, anyone else I may be forgetting. I just fixed that SVT Pro 7 which is Class D and SMD... and it has led me to think about offering repairs on more of this type of gear such as home stereo equipment. Thought I'd pick your brains as to what this may entail as far as equipment, parts, repair skills etc... My biggest question is are parts for stereo equipment repairs generally available? Is this service MUCH different than repairing bass amps?

[Jazz P Bass]

My thoughts on home stereo.
The schematics may be a bit difficult to find.
There is an awful lot of separate circuits
Most of the newer ones use one or more microcontrollers. Imbedded logic that is difficult to ascertain.
The good news is the output sections are output sections.
An awfull lot of the stereos use an output chip.
That makes it relatively "easy" to repair a blown output.

[lowell]

Cool. Do you yourself do this kind of work?

[Jazz P Bass]

Yup.

[lowell]

Do you only repair the power amp parts? Or all parts? Where do you source such specific parts from? Do home stereo manufacturers sell replacement parts and or have tech support?

[plec.22]

I would agree with jazz p bass there, most new hifi equipment has stk modules and all manor of ic's that control things... the older hifi stuff used op-amps/s s parts and made life a little easer to turn the repair round faster even cd player's with not playing the cd's you just replaced the opto unit and it was up and working again..

Getting schematic's on some unit's can be hard as manufactures want you to send it to them and they charge the earth for what?? a few minutes work changing a board and saying that will be ex amount of£££ or$$$ please... I would say it's getting harder to fix things these days as they cramp so much stuff on to smaller pcb's...we've all seen that..

[Ronsonic]

I can and have fixed a lot of stereo pieces. The catch is this, the fun simple old stuff has not historically had much cash value. The big money has been in high end home theater stuff that is generally not suited to component level repair and not subject to the usual fixes.

That's changing. People are increasingly willing to pay good money to get the classic silver-faced Marantz, Pioneer and other gear fixed. Those fall in the category of being "just electronics." You will have to deal with tuners to some extent. Otherwise it's just audio electronics.

Me, I get singing furniture all the time. Especially old tube Grundig and Zenith and such.

[52 Bill]

Ditto here, vintage stuff can be a joy to work on.

It's hard to find profit in repairing disposable stereos made in China, when the retail price is often half the repair costs.

[plec.22]

Ditto here, vintage stuff can be a joy to work on.

It's hard to find profit in repairing disposable stereos made in China, when the retail price is often half the repair costs.

Total agree there with bill aswel... older vintage audio is built to last and once repaired to spec they have that warm sounding effect unlike the china crud.... I've a mid 80's pioneer sliver amp and the only repair it's had is one channel as it was leant for a party many years ago.. still it sit's on my unit now in full working order.... the older units had more head room than there quoted power.

[jrfrond]

A lot of current run-of-the-mill hi-fi gear is disposable junk. I was an audio/video repair tech for a major NE chain called Crazy Eddie all through the 80's, then another place for a couple of years after that, at which point I got back into the "pro" market. BTW- you can all laugh at the commercials and sillyness of Crazy Eddie, but our tech shops were the best in the business, and it's where I learned to run a shop properly and at a profit. Anyway, equipment was actually "real" back then, and repairable with good parts availability. Toward the late-80's, I started to see the trend toward disposable gear, starting with "small goods" e.g. Walkman/Discman-type units, then VCR's, etc. It started to get ugly after that.

I try to avoid consumer good repairs like the plague here in our shop, which is geared for the professional market, but there ARE occasions when we will take in cool vintage stereo pieces to repair. There is also a lot of "Pro-sumer" gear floating around that we tackle. The lines have been blurred on some items.

If I were in your shoes, I'd approach it cautiously, and attempt to repair only the items you feel you'd be successful at.

[lowell]

Thank you all for the tips. So what is consider Pro-sumer? Can you list a couple makes and models for me so I can do some reasearch?

[plec.22]

Jrfrond..I also started in the 80's and worked on old wooden tv's such as redfustion.. Grundy.. gold star..normindy..and and plenty of top loading video's... and plenty of sony gear.. there was the good side of working within a repairs shop..you got to pick the junk pile for parts and put together a solid peace of equipment mmm the good old days.. I even got plenty of spare from that pile... that's when you had old engineers who had plenty of time to teach you there skill's... and you learned your trade.... one of my pet hate's is keyboard's there a real pain, full of plastic parts that break all to easy..

[Jazz P Bass]

Me, I get singing furniture all the time. Especially old tube Grundig and Zenith and such.

Ha, ha , ha.

Thanks for the laugh.
"Singing Furniture"

[pdf64]

Hifi schematics - grrr! I'm still trying to track one down for my Marantz PM-48 amp (BF! ha); I seem to have found everything but.
The upside is that I worked around it by taking a post volume feed to my old Rogers stereo tube power amp. Pete.

[Enzo]

Old Pioneer, Sansui, Marantz stuff is easy enough to repair, but later stuff, I have found suffers from parts problems. I have no problem swapping out an STK chip, but often on some Technics receiver, or JVC or whatever, there will be a custom IC that does all the analog switching - channel selection etc - and it will be bad. Not a generic part, you have to but a replacement from Panasonic or whoever for $35 plus S/H. Or some similar situation.

Companies like MCM, B&D, etc often have a lot of specific parts.

I am not so interested in consumer audio these days.