Yamaha C-4. Capacitor types on the main board.

[Hifibythekg]

Hello..
Does anyone have a list (BOM?) for replacement of capacitor types ('low ESR,' or 'good for power supply' designations is what I'm really after) on the Yamaha C-4’s main board?

(The ‘Function C Board NA 07149.’)

Could probably buy all Nichicon FG or Panasonic FC but would be grateful if anyone can offer a more finessed list.

Tried looking through previous posts but just couldn’t find one.

 

[Nashou66]

I like Panasonic FC and FM for power supplies. I think Nichicon KW's are used there by many as well.

But some timers I just use what I have in stock

In the coming months I need to replenish my supply so I'll get another storage cabinet for PS caps only.

Athanasios

 

[Hifibythekg]

Thanks Athanasios.
I'm attaching a snap of the board in question. Apart from the Bipolars, should I use Nichicon UPW, or Panasonic FM's in all the areas circled with the black marker pen?
Or would some areas benefit from caps with other qualities?
Are MUSE caps best for the bipolar replacements?
And the Yamaha blue box 1uF/100V what's an ideal replacement?
As I can choose from Mouser, look forward to hearing views on the ideal selection.

 

[Hifibythekg]

Is there an ideal cable gland for the C-4?
I'd like to replace the power cord. Might be an @avionic grade question..

 

[raycarr00]

on the yamaha 1uf's, i used solens. nichicon and muse on everything else. was working on diodes and off spec resistors, last. this thread might motivate me to keep going- lots of parts...

 

[Hifibythekg]

Thanks @raycarr00
Looking at this, and other threads..
Thinking I should populate the area 'A' with UPW's or Panasonic FM's.
The remaining areas with Nichicon KT's. If they're not available, use Panasonic FC's.
Bipolars all to be Nichicon Muse / ES
Anything wrong with this?

 

[mbz]

Will send you a pm with spreadsheet of my refurb, it's a start. Today, I'd do it slightly different, prefer Nichicon KZ/FG over silmic II in audio path.

 

[avionic]

FG over silmic II in audio path.

Silmics are EOL discontinued..

 

[avionic]

Is there an ideal cable gland for the C-4?
I'd like to replace the power cord. Might be an @avionic grade question..

I don't replace them unless there bad. I don't care for IEC plugs.. IMHO most installs look like ass unless one uses and IEC hole punch. <-- That cost around $250 --

 

[Hifibythekg]

Thanks guys!
@avionic can the original cable glands be reused, or does extracting them ruin them?

@mbz , spreadsheet received and incredibly helpful for this amateur.

 

[HPMguy]

The 1uF looks like a film cap to me, check the parts list if possible. No need to replace if that is the case, but if you do, I'd use a film cap there. Should be some with 22mm lead spacing, or whatever those are.

For power supply I use Nichicon UPW, UPM, or UHE depending on what I can get. 105C and long life, and use the "low impedance" selection if there is one (Digikey). Nichicon, Panasonic, Kemet, CD, any low impedance series is what you want. NOT "audio" grade, you want the lowest heat generation in power supply caps. Same goes for de-coupling caps anywhere.

If you look closely though, you will notice that almost all the caps installed at the factory are the same series and probably "general purpose" ones at that. Only caps with yellow or orange jackets from Elna are special, and those are always low leakage and nearly always test just fine. The only difference in using specific types is lower distortion/noise and longer life in high ripple locations. I really doubt anyone would be able to tell the difference in the output if you used all general purpose caps except for the ones originally low leakage, and even then modern caps are probably as good as the original low leakage ones.

 

[Sparkplug]

Thanks @raycarr00
Looking at this, and other threads..
Thinking I should populate the area 'A' with UPW's or Panasonic FM's.
The remaining areas with Nichicon KT's. If they're not available, use Panasonic FC's.
Bipolars all to be Nichicon Muse / ES
Anything wrong with this?

I’d use Toshin UTSJ series for audio path where necessary, they’re more expensive but higher quality and more transparent than anything else. I think they’re available at Farnell. Also outside the power supply board, changing caps en masse will noticeably (very noticeably in fact) change the Yamaha sound signature … bear that in mind.

 

[avionic]

Thanks guys!
@avionic can the original cable glands be reused, or does extracting them ruin them?

Yes..If not ..

https://www.mouser.com/c/wire-cable...t/?q=strain relief&type=Strain Relief Bushing

 

[Hifibythekg]

Thanks @avionic what an array, all 56 of them.
I don’t have the C4 on the bench at this time, can you tell me which one you use?

 

[Hifibythekg]

Thanks @HPMguy and @Sparkplug all good to know.
Cheers

 

[avionic]

Thanks @avionic what an array, all 56 of them.
I don’t have the C4 on the bench at this time, can you tell me which one you use?

You will need to measure the diameter of the panel opening. If you destroy the original strain relief gland.

 

[HPMguy]

Eh, don't sweat capacitor choice too much. Anything new you put in will be better than the 40+ year old ones in vintage electronics.

 

[Hifibythekg]

You will need to measure the diameter of the panel opening. If you destroy the original strain relief gland.

Thanks, will do.

 

[Hifibythekg]

Eh, don't sweat capacitor choice too much. Anything new you put in will be better than the 40+ year old ones in vintage electronics.

Thanks, that’s quite reassuring actually, greatly reduces the anxiety that one might make a ‘mistake.’

 

[Sparkplug]

For electrolytic non-polar (no polarity, bi-polar) use, you could also consider Nichicon DB series:
https://www.mouser.com/c/?q=udb1h

These are designed for hifi speaker systems but can be used in any hifi audio equipment. I find their sound to be very transparent and clear. For me they outperform the Muse ES series, they also cost twice as much or more.