dual Triode, 9 pin…mostly for the random tube swappers….
Like i mentioned, Keith a superb engineer has you covered…
Like i mentioned, Keith a superb engineer has you covered…
Channel Imbalance Mystery
Get a GOD**** Tube Tester! I cannot imagine loving tube sound and denying myself the ability to have confidence or find problems in active and replacement tubes. Test the tubes, short? good or bad? go from there. Have the tester for the rest of your life! Get or download the manual. It's not rocket science. I test new matched tubes when I receive them. https://www.ebay.com/sch/i.html?_from=R40&_nkw=tube+tester&_sacat=0&LH_TitleDesc=0&_... this little tester has given me confidence and found problems for over 40 years. I have a big fancy one, they always agree, I don't bother with the big one anymore, I'm gonna give it away or sell it someday when I get around to it. https://www.ebay.com/itm/165066777164?hash=item266ebf224c:g:h-IAAOSw96BhPXpQ I would take it apart, hose it's guts with contact cleaner/lube, twirl the controls this way and that, blow it dry, wait overnight for further drying, and get right to it. |
Paul, it is probably an illusion created by room acoustics and imbalances canceling each other. My system has always run 3 dB hotter on the Lt in my current room. There is an alcove on the left side wall. In preparation for a new turntable I finally completed the built in cabinet for that alcove. My left channel now runs 1 dB hotter. Now if my right channel electronics had 0.5 dB more gain switching channels like you did would cancel out the imbalance. This is what a balance control is for. Unfortunately, that imbalance is hardly ever equal across the audio spectrum so your frequency response curve is being shifted. This is where room control is very effective. For reference a 0.5 dB imbalance is just noticeable. A 1 dB imbalance is obvious. |
This will solve things until you ascertain what is going on. Gives you remote balance as well as remote volume. https://www.ebay.com/itm/234116696552?hash=item36827149e8:g:FOsAAOSwhNlgmIqc Then, after you 'fix' whatever is going on, you have it, it is noise free 120db s/n and neither I or my friends can hear whether it is in or out of my systems. I love having remote balance from my listening position for the few tracks that need a balance tweak. A small adjustment can make a large difference, so much ’opens up’ when the balance is spot on. It also has automatic ’Loudness’, progressively engaged ONLY for low volume listening, the primary benefit is retaining bass presence, a big part of maintaining involvement at low level listening for me. |