Question About Capacitor Upgrade in Tube Amp

ANY cap upgrade is useful, power supplies included.

In general, the type of capacitor is more important than brand. From cheapest (and least good) to best: metallized insulator, film and foil, air gap, vacuum. There is a good discussion of this in 'Art of Electronics.

Next most important are the materials: polypropylene, styrene, teflon (insulators); aluminum, tin, copper, silver (conductors).

Polypropylene is not as clear, teflon can be a little harsh. To my ears, styrene is just right. Conductors are not as important, although there are differences. Aluminum is prone to corrosion and can be a little harsh. Copper is expensive. I find tin to be a good compromise.

I mainly use air gap and vacuum caps for the most important components, such as RIAA compensation. For amps, I usually use styrene.

For brand, I use MIT or Relcap for signal path, Solen for power supply. Phono stage uses Solen teflon for the final power supply filter. Good luck!

YMMV

From my understanding the existing non-polarized caps are silver film. I do not think they are junk but for a reasonable cost certainly am willing to upgrade them.

So no love for the Mundorf Supreme SGO 1000VDC caps here? I had originally been thinking of those.

And thanks for the advice to replace all three of them.

The electrolytics are Nichicon so I will leave those be.

The small film caps that are put across the electrolytics, are bypass capacitors.

A small high quality bypass cap can greatly improve the SQ from the bigger electrolytic.

I recently recapped a tube amp and I put Myflex capacitors with great success.

Also recapped a Marantz 7T and because of space restrictions, used Audionote electrolytics with Myflex bypass capacitors on each one. Also sounds fantastic.

Deoending on how long you plan on keeping the amp, buy the best capacitors you can justify putting into it. They will make a difference. Humblehifi’s capacitor list has served me well in the past when deciding on what caps to use.

And ignore the comments about your amp not being worth the effort. It’ll be worth the effort. Anyone who has done a recap, either themselves or by a tech will tell you it’s worth it. 

Paul from PS audio on caps…

He discusses caps/bypass caps.

Thanks! I will take a look. I have watched a few of his other videos before. Seems like a nice guy in addition to all his knowledge.