# Worth it to restore stereo amps from the 80's?



## shadow19935

Pics?


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## Firestorm252

Quote:


Originally Posted by *shadow19935* 







Pics?

I'll try to get some up late tonight or tomorrow. I'm up at campus til late tonight (campus is like 75 miles away from home)

You can tell they came out of the 80's though. odd to say why, but you look at them and it's like "Back to the Eighties" (which just so happened to be one of my HS marching band themes







)


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## kingsnake2

From the little research I've done, home audio, especially at the mid-high level, hasn't changed much over the past 40 years really. A lot of the 1970s-80s speakers are quite good still and I would guess the same would hold true for the amps. Right now I am restoring some 1980's kenwood speakers.


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## D3FiN3 SiN

It's worth it IMO.

Like kingsnake2 said, home audio really hasn't changed enough for there to be a huge difference with a new mid-range set.


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## Chipp

The AU-505 has potential. It was from slightly before all the big-name Sansui amps of the 80s, but still should be a solid lower power performer. Massive power transformer in that thing.

All the older potentiometers Sansui used pick up dust and grit much easier than other brands I've seen, so it'll probably need a good cleaning if you find volume controls or other knobs to result in scratchy noises. (Caig DeOxit is great for that purpose).


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## Firestorm252

+rep for those that aren't mods
















hmm that sounds promising then. Although I just looked up the AU505 and the one I have is distinctly different. Also makes me sad that the speaker cabinets that were paired with the Fisher didn't make it. They were stored in a different place altogether and when I checked them, the wood cabinets themselves were rotting away and the cones were so brittle they fell apart when I touched them.

also here's the photos of them. As a courtesy to those on slower connections I used the OCN gallery's medium-size, but click them to open up a full resolution image. Sorry for the graininess, best I could do with a Point and Shoot.

*Sansui A505 (also pictured AM/FM tuner T505)*





*Fisher CA-861*




the Fisher has the largest power transformer I've ever seen in a consumer product


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## Barten

ha ha, that's awesome


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## bumsoil

Vintage amps are where it is at.







i use a pioneer SA-8500-II for my home stereo.


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## pioneerisloud

I'd say its worth it definitely. I just got a Pioneer VSX-504S (135w RMS / channel @ 8ohms, 350w RMS @ 2ohms). Its also bridgeable at 2ohms







.

I also just got some 26 year old Pioneer 12" speakers. They don't build them like they used to, that's for sure. Granted my amp isn't "vintage". But my speakers are







.

Personally, I love Vintage audio equipment. They used to build them REALLY good back in the day.


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## Firestorm252

had some time to play with it and the CA861 just seems to have cruddy inputs. need to clean them out and clean up the PCB they're all connected to.

found out a little more about it too: the CA-8** line all had 100+ RMS/channel.
what that means speaker-wise I honestly have no idea








I'm gonna have to do some reading in my spare time









and I need to get some new cables. all these old ones that came with them are just plain worn. they've each got intermittent line breaks >.<


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## valtopps

for the price of a new one its not worth fixing. its a 2 channel new one are 5 to 7 channel with surround.


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## Chipp

Quote:


Originally Posted by *valtopps* 
for the price of a new one its not worth fixing. its a 2 channel new one are 5 to 7 channel with surround.

New ones are class D designs, in most cases, and dont do much better than the old stuff in terms of simple amplification. There might be more stuff in them for the same price, but that also means each individual part costs less.


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## Firestorm252

there anyway to determine the amp class? I haven't seen any markings indicating it.

if memory serves, the efficiency is one way but I've never dealt with anything with this level of power (most of my projects are portable, and consequently low power)
I dunno if I'm doing this right, but here's my thoughts on the Fisher:
_Power consumption_
550W
_Output RMS_
100-120W/channel (varies according to model in CA-8** line)

well, at the most-efficient case of 120W individually the efficiency is like 21-23%.
but since it's per channel that's like 42-46% theoretical efficiency.
coincidentally, the Fisher runs hot pretty much all the friggin' time, moreso when I'm actually running something through it while testing. That's like a 1-to-1 W, output power v. power wasted as heat









anyone got any idea? If I'm totally making crappy observations and connecting the wrong dots please correct me.


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## Chipp

Quote:


Originally Posted by *Firestorm252* 
there anyway to determine the amp class? I haven't seen any markings indicating it.

if memory serves, the efficiency is one way but I've never dealt with anything with this level of power (most of my projects are portable, and consequently low power)
I dunno if I'm doing this right, but here's my thoughts on the Fisher:
_Power consumption_
550W
_Output RMS_
100-120W/channel (varies according to model in CA-8** line)

well, at the most-efficient case of 120W individually the efficiency is like 21-23%.
but since it's per channel that's like 42-46% theoretical efficiency.
coincidentally, the Fisher runs hot pretty much all the friggin' time, moreso when I'm actually running something through it while testing. That's like a 1-to-1 W, output power v. power wasted as heat









anyone got any idea? If I'm totally making crappy observations and connecting the wrong dots please correct me.

It is likley class AB. D was not really around yet, and class A would not put out that much power without enormous energy wastes.


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## Almost1974

Quote:



Originally Posted by *Firestorm252*


found out a little more about it too: the CA-8** line all had 100+ RMS/channel. 
what that means speaker-wise I honestly have no idea








I'm gonna have to do some reading in my spare time







>.<


Hey Firestorm, I have 2 of the CA-861 amps just like the one u have ( they both work, just have 1 for standby), and must say YES it would definitely be worth it to have them fixed, I have had mine for about 16 years and still love it, oh and the CA-861 is 150w peak per channel, tho only 2 channels it kicks ass IMO,, I have 2 Technics SB-LX90 15" speakers on it, BUT a few years ago I replaced the stock Technics woofers with 2 Rockford Fosgate S2 15" 8ohm subs, they require a lil bit more power but the amp still kicks the hell out of them, I will post pics if anyone would like to see them, anyway if u have any questions just emai me

Almost1974


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## rollemup

Hi, first post here. It's a good bet they are class AB/B or some variation thereof. Not all new amps are Class D, and not all Class D are middle grade in terms of either quality or price, some of the absolute best and most expensive are Class D. Most of what you'll find in COTY stuff though? Pure junk, and that's regardless of class, but especially for class d. I make high end class d amps myself, and most companies using them don't know what they're doing, or use them just to save that extra penny, which is not the basis of a good product.

Based on these pictures, these look like very standard, mid grade or worse components. That doesn't mean they're not worth fixing, because if you spent an equal amount of money representative of what these suckers were worth back in the day to get a new amp today, I can almost promise you, it's just not going to last you thirty years, in fact you'd be lucky if it lasted you thirty days. Yeah, it is a sign of the times.

At least with this old stuff, you're paying less for gimmicks and junk, standards they try and shove down your throat that aren't really and never will be truly standard, but merely push you to purchase based on new features that they try to make you feel the need for.. pure gimmicks.

Even if these are mid to low grade junk amps, many of them had great reputations, and as I pointed out already they lasted awhile so they can't be all bad. I would say they're worth fixing just for the lessons they can teach you on their own.

A few months ago someone gave me a broken down thirty year old yamaha "natural sound" amp, they'd even cut the power cord off and were ready to throw it out. I took one look at it and said sure... I"ll see what I can do with it. Why? A glance showed me it had some seriously high quality audio grade components in it, like Elna Cerafine caps in the main power supply. They don't make caps like that anymore because of the flood of cheap junk from China, and manufacturers always strong armed into making something at a price point people want to afford. Quality like that costs money, and they felt they no longer had the market for them. When I got the amp home I discovered it was also stuffed full of Black Gate caps, Nichicon audio grade and other types of Elna audio grade, along with some very high quality audio grade choice transistors.

There were almost no toys in this amp, and just a few "flaws" preventing it from being seriously high quality, but it was a commercial product after all. More so it used some really smart design topologies and tricks that gave it certain "natural sound" characteristics that thirty years later people still aren't smart enough to aspire to in new products, like a flat, load invariant frequency and THD response across the full audio band and beyond.

The guy gave it to me for junk parts because he knew I was into that sort of thing, but I spent a month fixing it and sold it back to him for a small fee, because you just don't find that kind of quality these days at an affordable price. I was also able to fix it without needing any new components, I just bypassed an open pot that had worn out, nobody really needs "balance" controls anyway, and repaired a few cooked traces that occured when he tried to drive an amp with an amp because the open pot was preventing real volume. Additionally I resoldered the entire board, cleaned it all up, checked the bias, and gave it a few very simple and easy little tweaks. It could last another twenty years.

What you'll want to do is check out the pots /sliders/switches because they can and do wear out or get dirty. You'll also save yourself some trouble if you just start by resoldering the entirety of it, because solder actually ages and becomes brittle over time, where it then develops micro cracks, probably right across the board but especially for heavier components like power caps and switches which get depressed/stressed frequently. As they heat and cool with load they'll kind of rectify and you'll hear it as noise, crackling, popping, etc.

Resoldering alone could fix what ails it. Also be careful cleaning it because while it probably looks gunked up it's likely coated in varnish or some sort of conformal coating to protect it from the elements. Give it a good dusting but don't take the cleaners to it needlessly.


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