I installed some upgrades to my Quickie:
I have replaced the stock volume potentiometer with an Alps RK27 100k Ohm. That got rid of a slight channel imbalance and also improved the sound quality noticeably.
Additionally, I have replaced the stock RCA 3S4 tubes and installed NOS Telefunken’s DL92 (3S4).
The next upgrade will be a replacement of the output coupling capacitors. Following a discussion at the Bottlehead forum, I have ordered 2.2uF 630V ClarityCap MR Range polypropylene (CCMR-030) from the UK, which I will install once they arrive.
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