BHK Pre Amp Volume Clicking

I hear the continuous clicking with the BHK pre volume control through my Quad 2905 speakers when using XLR Iconoclast interconnect cables and Inonoclast speaker cables connected via BHK 300 monoblocks.
I don’t hear the clicks when I replace the BHKs with a pair of
(March Audio) Class-D monoblocks even with the volume matched between the BHK & March amplifiers.

I did just change from the factory tubes to some 6V tubes from Upscale Audio. Made a nice difference in clarity and body of sound. However, now I have very distinct pops on the BHK preamp at specific volume transitions. 32-33, 40-41, 52-53, 68-69. Other increments have a minor clicking noise, but these transitions are LOUD. I have balanced inputs from DAC to preamp, and RCA from preamp to amp.

I have the same with Mullard Tubes and the stock ones. I believe those are expected. Read up the thread.

My experience with volt tubes is that they are noisier than twelve ones. It is very important that the tubes are not only matched paired to each other but also triode matched. I personally only get the mechanical click from the preamp, nothing from the speakers and no noises between the other steps. Are you runnig unbalanced cables to the amp? My sytem is fully balanced.

The noise I get is not mechanical I believe. That happens on power on. What I get is each click up in vol is a pat pat sound…very soft. But at 2 or 3 spots 52-53 is one i remember is not just a louder click but a more significant increase is volume. But it was that way with original tubes but the new ones as well.

Thanks for the replies. i did read the whole thread. For me the pops are coming from the speakers, not mechanical. Balanced xlr from DAC to pre, RCA from pre to amp. I had mild popping with factory tubes, much louder pops with the new 6volt tubes. Happens only at specific transitions (52-53, 40-41, 68-69, etc.). I understand that a resistor explains 52-53, not sure what causes the other transition points.

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I know I hear more than just 53… And yes mine are from speakers too.

The unbalanced connection to the power amp is the reason you are more bothered by the clicks. There are resistor steps 24 25, 52 53 that I am aware of never pushed higher to see if there are any more.

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i had a problem in the past with loud clicks with volume changes after i changed tubes, and failed to move the jumpers. You might want to make sure jumpers are in proper setting for tube type - 6v or 12v, and 4 or 5 mA bias. Prior owner may have made quick tube change and forgot to do that…
James has great video on tube rolling and those jumper settings

I have always used appropriate strapping when rolling tubes. The mechanical clicks of the relays which are a function of the design of the volume control are the ones that I was speaking of. If you use tubes that are not triode balanced you can get noise at all other steps of the volume control. 6 volt tubes use a higher bias setting of 5 ma and yes they will also work with 4 ma with slightly less tube rush. Using balanced connections results in much quiter transitions than when using unbalanced RCA connections.

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