@bruce-in-philly
A problem I am experiencing is a 120 hz buzz when DSJR is hooked to preamp.
If you could ignore the loud buzz, the soundstage and everything else is much better than the dsjr going direct in to power amps.
as to the hum…the unit is at ps audio now, searching for an answer.
This is what I have done so far in my experiments (any suggestions?):
Issues: 120 HZ buzzzz when DSJ attached to two different pre-amps, AND, a Digital Gurgle sound when attenuator is out and DSD player input to USB port when vol. above 77.
1- When the DSJ was outputted to a just received used ARC LS3 with the DSJ attenuator in or out, I heard a very loud 120HZ BUZZING noise. I immediately returned the ARC LS# figuring it was broken in shipping.
I purchased a new Quicksilver Line Stage preamp and hooked up the DSJ. When the preamp volume is above 40% there is the same 120HZ buzzing noise. After some simple research I understand this to be a Ground Loop. The Buzz increases as the preamp’s volume increases. The most I can possibly stand is 49% Pre-amp volume. Not optimal.
With other sources the preamp is dead quiet, yet with the DSJ hooked up to either an SS pre, or a Tube pre I get the same 120 HZ Buzz. I have tried lifting the ground on the DSJ with a cheater adapter, and even power cords with the third prong removed. I have tried many variations: DSJ ungrounded and the pre-amp grounded, Pre ungrounded, and the DSJ grounded, one mono block ungrounded and the DSJ and the Pre-amp and one mono block grounded, both mono blocks ungrounded and the DSJ and pre-amp grounded… You name it I tried it. I even tried both a dedicated 4 way outlet box and several different outlets in different configurations, nothing helps.
I hooked up a SACD player to the pre-amp, dead quiet, PS4 to the Pre-amp dead quiet, nothing hooked up to the pre-amp dead quiet, etc, but as soon as the DSJ is hooked up to a pre-amp…BUZZZZZZRRRRRRRRRRZZZZZZZZ. Sounds like an ungrounded Turntable. Not White Noise.
2- When attenuator is out and I have a DSD player inputted to the USB port and the volume is above 77 I get a digital gurglely sound out of the speakers during the silent lead ups to a track (to hear it specifically you need to put ear close to the speaker on the silence sections, but causes general distortion fatigue during normal listening).
I have dealt with this by keeping the DSJ at below 70, not optimal. In order to bypass this problem I ordered an Audio Research LS3Pre-amp used from "The Music Room, and later a Quicksilver Linestage Pre-amp new. (see above), but instead discovered another worse problem.