Yamaha m-4, C2a preamp, and matching tuner: usual repair and opinion?

ryuker16

Active Member
So I recently recapped my first reciever(a HK590i) and when I told my uncle he mentioned having the above Yamaha components. He said he paid a pretty penny so he wants me to pay $150 for it.

He hasn't used it in years and doesn't know the condition very well(a friend sold it to him).

What's Likely to be busted? Are the caps expensive and numerous? I read a few stories of repairs and I heard this unit(m-4) can be expensive to work on. I'm really short on cash so even $150 is pushing it.

Lastly, how's the SQ? I heard it's amazing but would it put my recapped Harman kardon 590i to shame or merely sound different? I'm pretty happy with my vintage setup as is but the reviews are simply amazing.
 
Thats a steal...Lights,dirty switches and solder connections are the norm..
T-1 or T-2 tuner?
 
I believe it was the t-2 tuner. I don't ever listen to radio*. Maybe I should recap the tuner and sell it?

*Radio choice in my area is pretty bad. Clear channel did us no favors.
 
I believe it was the t-2 tuner. I don't ever listen to radio*. Maybe I should recap the tuner and sell it?

*Radio choice in my area is pretty bad. Clear channel did us no favors.

If its a T-2 ,let a pro tackle that and a full alignment..
 
The M4 is one of the easiest amps ever to work on. IDK who told you that it costs alot to repair and what not. I have 2 of those amps and love them. One i'm in only $50 with it and its fully recapped minus the big power caps but thats it. Was dead in one channel but brought it back to life and sounds awesome!!!

The C2a is a pretty nice pre-amp and rare i do believe. And the T2 is one very good tuner which i would keep but if you have no use for it then sell it but do give it a listen and see if you like it!

$150 for that whole stack i would RUN for it!!!
 
The M4 is one of the easiest amps ever to work on. IDK who told you that it costs alot to repair and what not. I have 2 of those amps and love them. One i'm in only $50 with it and its fully recapped minus the big power caps but thats it. Was dead in one channel but brought it back to life and sounds awesome!!!

The C2a is a pretty nice pre-amp and rare i do believe. And the T2 is one very good tuner which i would keep but if you have no use for it then sell it but do give it a listen and see if you like it!

$150 for that whole stack i would RUN for it!!!

I think somebody said if the PSU is bad it was a pain and hard to find a replacement.

:banana:

Awesome! I'm reading up more on it. Apparently it used higher quality mylar and film caps mostly so I'll assume I'll have less caps to replace on the M-4?

Less-caps? Sounds like my kinda refurb!
 
Do a search here in AK on the Yamaha M-4. There are lots of threads about recapping the M-4.
 
think somebody said if the PSU is bad it was a pain and hard to find a replacement

I think someones blowing smoke up your wazoo...:D
 
So I just got a parts list for the C2a preamp and yamaha m-4.

Seems they used Nichicron caps.......would using panasonic FM/FC series replacements be alright? I know it will work but will I change the character of the sound significantly(for the worse)? The Yamahas in this series seem to use alot more polystrene and mylar caps for the more important functions(I assume).

The replacement parts list came out to $10(!) for the C2A and the Yamaha M-4 I'd doing the price search now.

Worth getting audiophile grade caps? I'm on a budget... but these don't have many electrolyte caps at all...much cheaper than my HK recap!

EDIT: I used Panasonic FM/FC series caps on the HK. Sounded much better and most of those caps were good(Rubycon and TK caps originally).
 
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Panasonics will due just fine...Use Nichicon ES 'MUSE' series for the NP/BP caps in the C-2a.

So panasonic for the AMP and save the good stuff for the Preamp.

One more question....I heard the big electrolyte caps rarely go bad. If my gigantic 15,000 uf caps appear fine is it best to leave them and recap the smaller one. I'm waiting to hear back about 2 new jobs and money is tight.
 
So panasonic for the AMP and save the good stuff for the Preamp.

There is only 2 non-polar/bi-polar caps in the M-4's PS/Protect circuit.The C-2a uses them for audio coupling (audio path) Nichicon ES audiograde.
 
T-2, C-2a and M-4 is a sweet Yamaha stack!

Get them healthy and up to spec and you should be set for some time.
 
Got it!

Heavy and built like a tank!

2CvtS.jpg
 
Just opened the C-2a preamp....

Flawless....not a single fleck of dust(the board is mounted on the case ceiling).

Caps apear to exhibit zero doming or damage/leakage.

It's like brand new....jesus; you guys weren't kidding....build quality and the soder joints look like it was brand new...

Now trying to get deoxit inside the jewel case pots...some have holes luckily.

In terms of vintage I think more people should be buying these yamaha elite stuff....aside form deoixt and bulb replacement; the maintenance is utterly minimal....

Compared to my HK reciever; this is a cake walk.

Restoration seems to be an oxymoron....doesn't look like it aged a day.

EDIT: nix that about being easy.....reaching the pots to put in enough deoxit is painstaking.....literally nightmare level.

The volume pot box is long and hard to reach....let alone difficult to get into it....I'm afraid to crack open the pot boxes at this point.
 
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