- I’ve slowly switched over from a dead silent, but poor sounding AV receiver, to a mostly full set PS audio components that sound significantly better, but that have increased the background noise on my extremely sensitive 101db/1m speakers.
- Current Components: Panamax Power Conditioner —>PS DSJr —> PS BHK Pre—>PS M700 —> JTR 212RT Speakers. Interconnects are XLR
The M700’s alone with the preamp turned off or with the preamp set to volume 0 do produce white noise but it is not audible at the listening position, however this white noise does become audible within 2ft of the listening position so it is just barely below the noise floor of the room.
The M700’s directly connected to the DSJr without the Preamp adds a noticeable and listening position audible amount of background pure white noise. This noise is constant in relation to volume on the DSJr as one would expect.
Adding the BHK pre to the signal chain notably improved the overall sound but has had an adverse affect on my background noise situation and I want to check with the experts if this is normal or if I possibly have noisy tubes or some other issue in my setup that I need to investigate.
As soon as I switch the preamp from volume 0 to 1 I get a audible jump in background noise at the listening position. As I increase the volume step by step the background noise gets progressively louder until I reach the next major volume step. This noise sounds like a combination of signal gain white noise, which I’m assuming is coming from the adjustments in tube gain, and a less appealing “electricity” sound, not hum, but electricity. Some volumes have worse electricity sounds than others so therefore those sounds are not purely progressive like the signal gain white noise. By the time the preamp gets up near a major volume switch, such as volume 24 or 52 there is a lot of background noise, more than when running the DSJr directly into the amps. However, when you click over to the lowest volume of the next volume set, say 25 or 53, the tube gain noise drops significantly and all that remains is the “electricity” noise.
The quality of louder sound is very similar/identical between volume 24 and 25 or 52 and 53, however I can hear very different noise floor levels in these volumes and end up picking my volumes around low tube gain volumes. This tube background noise is not as pleasant sounding as the DSJr’s white noise, when I turn the BHK volume up to 80 to 100 (line level and above) I can hear the DSJr noise again like I could before the Preamp and it definitely has a different character than what I’m describing above.
Is this standard behavior of the BHK in the way that it utilizes tube gain for volume adjustments? Should there be noticble background noise differences immediately before and after the major volume steps?
Has anyone else noticed this background noise structure in their setup?
Any recommendations on what I could try to reduce this noise?