Upgradng Yaqin MC-13S - Parts Questions

First, my appologies, I may not know the best formatting as I'm new to this forum, so I hope my post is functional enough. If not I'm willing to learn!

I have an audio repair person helping me with some upgrades for my Yaqin MC-13S. I am also getting started with DIY audio and am planning to try a preamp soon - but I'm not ready yet and I want my amp functional before the holidays :) Also, I might not have gotten the specs right from my repair guy. I think I'm close, but looking for help there too.

The upgrades we are attempting are listed here... although the documentation is a bit sparse:

Yaqin MC13s Upgrades and Switchable Feedback Installed – AD Audio Consultants


An externally hosted image should be here but it was not working when we last tested it.


The quick version is that they made these changes:
Elna Silmic bypass capacitors,Mundorf ZN coupling capacitors, and Takman carbon film resistors, and a switch to disable negative feedback.

My repair person gave me the parts I would need, although I wanted to double check because he's ultra busy - and I want to make sure I understand as best I can.

1) Coupling Capacitors: .47mF 600v(or more) x 4
2) Bypass capacitors: 470mF 25v x2
3) Grid Resistors: 2w (or 3) at 820 ohms
First - could someone confirm this is accurate from this schematic:

Second I was planning on:

Mundorf Supreme SilverGoldOil caps
and Audio Note Silver non-magnetic Resistors (820R Ohm, and 2Watt).
Are these decent choices?


Thank you in advance for looking over and helping me.
 
Hi, I know this is a year old thread but i'm also interested on this!
Did you go ahead with the mods? I thought the major change would come from swaping the 4 coupling caps, not the bypass caps. Can anybody share their experiences about changing caps on this or similar amps?

I was thinking about using cheaper caps, the most I'll be willing to pay for would be Audyn Cap Plus, Mundorf Evo Oil or Jantzen Superior Z... I'm considering too Jantzen Cross-caps, Solen Fast, Wima MKP10, Russian PIO k40y or k42y, Illinois Caps...
 
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I was reading this post yesterday as I got my hands on a MC-13s recently. In past I have used WIMA and JFX coupling caps in Cayin amps with good results. Russian pio caps surely have better SQ but the size is something I am not sure will fit underneath preamp board in MC-13S.