BHK Pre Volume "Click"

I have a BHK Pre and BHK 250 combination.

Since the beginning I find that the pre has a noticable “electical” sounding “click” whenever changing the volume.

When increasing the volume it “clicks” each numerical volume increase. When decreasing, it only clicks every second numercial.

Is this normal or could there be an issue?

Strange that the volume control/increment isn’t completely silent.

Thanks in advance.


That is normal and to be expected. The BHK volume control is the heart of this preamplifier. Unlike a standard volume control or stepped attenuator, the BHK instead changes gain of the vacuum tube stage in small 1/2dB steps and this is what you are hearing.

It is this unique volume control that helps the BHK be as good as it is.

This issue has come up before. Paul explained that designing a volume control that doesn’t negatively affect sound quality is a difficult job. The system that Bascom King devised does exhibit the clicks; I can’t explain all the details, but the clicks seem to be the price to preserve the SQ.

That said, I noticed:

a) the clicks became much softer when I switched from an RCA to an XLR interconnect between the preamp and amp (I also have a BHK 250). I now hardly hear them unless I listen for them.

b) there was inconsistency; as you said, clicks did not behave the same way going down as going up. Even going up I occasionally got a “skip” in the clicks.

So I don’t think your unit is faulty.

Edit: Paul posted his reply while I was typing.

Thanks for both replies! Glad to hear it is normal. Certainly having some clicks and maintaining the sound quality is the best outcome!!

I am using RCA interconnects at the moment, but will change to XLR in the next few weeks. Will be interesting to compare.

Only had the units for a few weeks now and loving them.

(Also have a P10)