Question About Capacitor Upgrade in Tube Amp

If your looking to upgrade coupling caps you can also play with the value of the

caps because they play a critical role in output impedance. For example,  I purchased a tube preamp which sounded terrible, no dynamics, no amplification.

Turns out there was an impedance mismatch between my amp(LSA class D) and the newly purchased preamp. After some research, I purchased a slightly upgraded cap with an increased value and surprisingly, it worked and am extremely happy with the outcome. Wanted to give my 2 cents cause coupling caps play a critical role, whether you're upgrading or changing the value, dismissing it's importance is  just anti-audiophile.

I've used most of the caps mentioned here and have found the Duelund Cast, in my case tinned copper version relegates every other cap to  a distant second place, really special cap, future plans for going into my speaker crossovers as well. I also like bypass film cap on electrolytic power supply caps if one doesn't have room for all film caps.

Charles is correct, SET circuits low parts count, so every single part change has bearing on sound. Resistor upgrades also worth investing into.

Once I get this one done I will take a look at the Muzishare X9 next. It is also a SET 300B and better built than the Willsenton. It also has the clarity of solid state with the warmth of tubes. But it is lacking in bass. It may improve with more run in but I suspect a few capacitor value changes will help. Although I am not knowledgeable enough about electronics to really follow what is happening in the circuit.

It certainly is a fun hobby and I appreciate all your expertise.

@calieng

You certainly have quite the amplifier stash. I wrote earlier that the Bottlehead tube products were although inexpensive they are well thought out engineered components. A price point is targeted and so the best quality parts can not be utilized.

Well, it seems that this principle is applicable to the Muzishare and Willsenton amplifiers. Good solid design with decent but not the best quality parts due to cost restraints. So very good candidates for upgrading part quality to achieve better sound. I believe that your project will turn out fine.

Charles

Yes too many amps right now. I ordered the Willsenton R300 and the Muzishare X9, X10 just in the past weeks with the intent of auditioning them and only keeping one or two. It is hard to decide before hand when there is nowhere to hear them before purchase.

The Muzishare R100 I have had for a while and is already for sale in the local craigslist. Very nice amp but I just do no need that much power or heat of the 845 tubes and it is also a bloody heavy thing to move. But no complaints on the sound quality. Very nice.

I have already decided the Muzishare X10 is a keeper as there is no other amp that I have that grabs the speaker drivers like those Kt150 tubes do. It would be the one for more modern / pop music. The bass is tight and bold and really gives you a punch to the chest when turned up.

Of course someone else may have different opinions as system matching is always much more important than the tweaking of capacitors and tubes.

Cheers.