Bought a BHK set and it makes to much noise

Hi I bought a used BHK 250 amp and pre-amp
the combo makes more noise than my LM845P tube amp, Also when I use the volume control it makes noise in my speaker. There’s no noise when uisng the volume control on the remote.

Does the combo needs some new tubes?

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My combination is almost silent except 1 inch from the tweeter where you can hear a faint hiss. The likely culprit are the tubes. If you find the thread there are many choices. I stick with NOS 60-70’s tubes, Telefunken in the Pre and Lorenz in BHK amps. Hard to go wrong with NOS European tubes.

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Hi do you live in Europe? I live in Denmark and would like recommendations for some tube stores

I’m in Canada. I’ve been building a collection of tubes for BHK’s over the years. Others can recommend some European tube sellers. I’ve used Langrex in England and they are reliable and have good support. JAC Music is a German store I have used also. Both are good and know their tubes.

I too operate the BHK Preamp and BHK 250 amp in my system and using 12 volt tubes in the preamp makes for the most quiet performance. Every 6 volt tube I have tried has had tube rush noise. I am currently running Conn (Sylvania) NOS tubes and the preamp is very quiet. I get no noise from adjusting the volume levels either manually or by the remote. My speakers are 93db per watt sensitive and I would have to put my ear in front of the tweeter to hear and noise at all and even when doing that it is barely audible.


Are you using RCA or XLR interconnects? I’ve heard that the BHK gear is definitely nosier if you’re using single ended RCA’s.

XLR cables

This may be subjective, but I feel by design Schuko is prone to inversion of N&L. Also, I feel that all equipment in the stack must have the same L & N orientation otherwise, there could be noise issues. Just a personal view.

Edit: I found this which better explains my thought.
AC Polarity - HiFi Reference

If you plug the cable pictured on the right into the socket pictured on the left the proper connections would be made. No inversion.


You are correct. However, the illustration could help checking for correct polarity with plugs that are susceptible to inversion such as this:

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I just ordered a BHK250 from The Music Room and it’s on its way. I watched the videos with Bascom and Arnie. Was very impressed. Bascom designed for Constellation and using same sex devices. Wow. Then I read the manual. I’m hoping someone can calm my fears. The manual reads 250 watts at 8 ohms long term and 200 watts at 4 ohms long term. 500 watts at 4 ohms short term. I’ve never seen a power amp give less watts at 4 than 8 ohms. I have 4 ohms speakers. What’s going on here? Any help would be appreciated.

The BHK 250 is a bridged amplifier. Do not be concerned with the lower rating you will never ever drive the amp to 200 wpc contiuously. It is 500 wpc at 4 ohms playing music!

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Bascom is not the only designer to use all same sex output devices. John Bedini did as does Plinius. I am sure there are also other designers doing the same.

That’s kinda weird… :thinking:

I’ve looked at the specs for those amps a number of times, and don’t remember ever seeing the ratings presented in that format before. I looked at the referenced standard (IEC 60065) and it has to do with safety for mains powered electronic equipment. It almost seems like PS Audio is saying that the amp is more than capable of producing 500 watts continuous into 4 ohms, but anything more than 200 watts steady state causes it to violate the referenced standard.

Stop morosing about 200 watts steady state you could never drive it that way!

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