Stellar Gain Cell DAC channel imbalance at low volumes

Hi all

I have recently got a GCD and S300 combo, which I use to drive a pair of Zu Druid speakers. These speakers are very sensitive, so the volume on the GCD is rarely higher than 20.

I have noticed a channel imbalance at low volumes. At lower levels there is clearly more sound in the right channel, and as I increase the volume it shifts to perfect balance at a volume of around 10. This happens regardless of inputs or outputs used, including the headphone output.

I have also noticed that there is still some sound coming from the GCD when it is in mute, again mainly in the right channel.

Is this behaviour normal? Or do I have a faulty unit?

Apart from these problems I truly love what Iā€™m hearing from the Stellar amps!

Thanks for your help
Lukas

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I have SGCD/ M700 drives LINN KEILIDH 4 ohm/92 dB efficiency. Initially, I felt some imbalance ( Right channel > Left, just little, but I seems can tell the difference). I do not have mono recording, so cannot really verify it. I did speaker adjustments (pull them away from wall) and recently add two subs. I no longer notice the imbalance on my current setting. I guess, in my case, the imbalance is balanced out by speaker placement now closer to my listen position.
PSA support are very helpful, I guess you might want to check with them.

Channel shifting to the right has been a consistent struggle that sometime keeps me from enjoying the music. I had SGCD/M700 combo in the past and occasionally the sound stage would shift to the right even while the music was playing. I later installed the GAIA footers and they did help a bit. After upgrading to the BHK250 and DSD Sr, shifting to the right still bothers me on a regular basis. I just did a measurement using white noise and decibel meter, and the reading came back largely the same on both speakers. So I must say itā€™s either my hearing or the room, or both.

Thanks for your feedback. Itā€™s interesting that channel imbalance appears to be a more common problem than I expected.

Do you notice the imbalance on the headphone output too?

And what about the ā€˜muteā€™ position that still produces sound? Do you have this as well?

My GCD right channel is a little bit louder than the left one. No one but me or you would notice I supposeā€¦
Also, when on 0 volume, the left is muted but the right is still there albeit in low volume.

Iā€™d love to know why. No, Iā€™m not complaining. But, I paid loads of money for it and would love more than ā€œstill sounds good right!? So shut up.ā€

Tested on my SGCD, turn volume down to 0 and mute ( lcd screen shows ā€œmute 0ā€) I hear nothing from either channels ( well, just the typical white noise, to be exact ) up the vol for one click, lcd screens shows ā€œ0ā€. I think it is 0.5 dB, I hear both channels ok. I guess you might want to talk to PSA directly. When I rcvd my SGCD / M700 / P12, I asked several questions. PSA supports/Engineers explain clearly on what happens on my systems. Such as software ā€œbugā€, no impact to the sound and normal operation. Since I am OK with these small non-essential problem, I am happy with my current setup with these PSA gears.

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Cool, thanks for testing that.
Though I live in Japan, and customer service here (as in not the flashy geisha stuff that tourists see) is pretty tyrannical and bureaucratic. SO when next I go to the USA I will take it with me myself.

Thanks guys for your feedback. Just like @danny Iā€™m not complaining, just curious if the channel imbalance is a problem that can be solved (perhaps with a software update). The imbalance does bother me, especially given that the gain cell technology is supposed to avoid this exact issue.

I contacted PS Audio but havenā€™t heard back yet. Maybe someone from PSA could chime in here and give us their thoughts on this?

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I just did a unscientific hearing test on youtube. If itā€™s even remotely accurate, it confirmed my suspicion that my left ear hearing is not as good as my right - by one indicator per the video. For those of you interested, here is the link and you do need a headphone or earbuds for this.

Adding to this thread as I donā€™t see any more recent on this topic. I had an issue with my GCD in Aug 2021 where the right channel dropped out almost completely regardless of volume and PS Audio replaced a board for me.
Fast forward to Sept 2023 and now I am seeing a problem similar to this thread where my right channel doesnā€™t kick in until volume setting 4 or 5 while the left channel can be heard at volume setting 1. The right channel balances out with the left channel at volume level 7 or 8.
Also, changing the balance from left to right has very little impact on the volume level in either channel and at any volume.

I too have a right channel imbalance. Longstanding issue. Hearing test indicates an ear issue. Room shape exacerbates the problem A LOT. GCD provides a balance adjustment (mandatory) thatā€™s set at 10 left. No system change could rectify the problem.

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