A few weeks ago, I noticed that the volume of my late night listening session (in 2 channel) had gone up from setting 10 to about 25 on my preamp (this represents 7.5db gain difference). I have an integrated MCH system, and sure enough my five channel calibration disc, indicated the volume level of my mains were now 6 db below center and surround. When I initially calibrates they were at the same level. I had mysteriously lost 6 db of gain on my mains.
Since my MCH calibration disc plays in a modded Oppo, and my 2 channel is different digital source (music server with USB), the digital source cannot be the cause. I also rule out my poweramps, which are monoblocks. Unlikely they both take a 6 db hit at the same time.
This leaves my DAC (MSB Signature IV) and my preamp (Arc Ref 5SE) as the only two components that could be the root cause. Any idea what to look for, and what could have caused this 6Db drop? Only thing I changed recently are powercords, but losing 6db gain through PC switch seems too much of a stretch.
Since my MCH calibration disc plays in a modded Oppo, and my 2 channel is different digital source (music server with USB), the digital source cannot be the cause. I also rule out my poweramps, which are monoblocks. Unlikely they both take a 6 db hit at the same time.
This leaves my DAC (MSB Signature IV) and my preamp (Arc Ref 5SE) as the only two components that could be the root cause. Any idea what to look for, and what could have caused this 6Db drop? Only thing I changed recently are powercords, but losing 6db gain through PC switch seems too much of a stretch.
It is well known that removing earwax and switching from unbalanced to balanced increases volume by exactly 6db.
