Stellar Pre / BHK250 - HT bypass issue

Hey everyone

Having a small issue. Just got a stellar preamp which is running into my bhk250 amp. Sounds really great and I’m happy with the combo.

I’m however having a small issue I’m trying to solve.

I’ve got my marantz AVR running into the stellar via RCA. It’s then running balanced into the bhk250. When I switch from listing to music on input 1 to input 2 which is set to HT Bypass i hear a small thump in the speakers and the BHK250 starts flashing (enters fault mode).

If I turn the bhk250 to standby then back on it works fine.

Am I doing something wrong? Is there a trick I’m missing.

Thanks.

That’s odd. I don’t think you’re doing anything wrong. Perhaps you can reach out to our customer service people.

Thanks Paul. Have sent them an email.

@Paul
Odd? Really? Yet you personally know very well about this issue.

@jhsg
There were several threads and posts about this issue.

See thread:HT bypass thump issues

A lot of work was performed by customers to provide detailed reports of investigations about this topic which is well known by PS Audio.

After a lot forth and back, the conclusion was that Paul Mc Gowan told me on the forum that they do not intend to pursue a satisfactory solution for the Steller Gain Cell DAC and after numerous complaints the forum got rather tired of hearing about it and Paul finally asked me in a personal message to stop complaining.

Not that it is yet solved though.

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Unless you have a dedicated Home Theater room, the solution is:
Don’t use the HT Bypass option or at least don’t put it on a different pre set volume than the other channels.
The gain cell can’t handle sudden volume changes.

I do not care for surround sound at home. But do care for less boxes and good sound quality from any source.
So, A/V sources are connected to the television directly, the TV is connected via optical to the Stellar Gain Cell DAC.

That sounds really good. No lip sync issues at all and no thumps.

The downside is that PS Audio provides 1 optical input only, so my old CD player is connected via analog RCA, which defeats the purpose of my upgrade to the Stellar for the CD. But all CD’s are ripped to the music server that is connected to the USB input. Sounds also very good.

Nevertheless the Stellar Gain Cell DAC is advertised with that HT bypass option and that should work without the thumps as you would expect from a US$ 1600 unit.

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Interesting! Thanks for posting.

Am I reading correct that a work around is not using HT bypass but instead switching over and manually turning the volume up to 76 (line level)?

My biggest concern is my very expensive bhk250 potentially getting damaged.

Or you could build a 12V switch for the power amp inputs. Paul’s reactions are still great. :smiley: Customer service will send you a new PIC and you have to swap it out which does not fix the problem. So skip it, do not waste your time. Buy another pre amp.

Jeez Louise Rudolph, get up on the wrong side of the bed this morning?

If you’d be so kind as to point me to where I said we do not intend to provide a satisfactory solution I’d be appreciative.

I believe what I said is that we have tested a number of units with a small thump when you switch to HT bypass and that thump was not enough to kick in any sort of problem, let alone put as BHK in standby. The problem as described recently is indeed odd to me.

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Oops… King Paul came out of the garden… :rofl: :rofl: :rofl: :rofl:

This happened to me, not on HT bypass, but when I unplugged the power to a phono preamp while my BHK Pre was unmuted. Basically, the source discharged itself into the preamp and caused a big thump downstream that put my monos into protection mode. Lesson learned.

HT bypass is likely worst since it’s sending the signal through at line level.

Ideally you power down the amp, then pre, before you power down the upstream component so it’s not discharging downstream.

If you use a harmony remote like I do, sequencing the power down is possible. Mute, switch inputs or power down the preamp or integrated amp before powering down/switching the upstream source.

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Read the thread and all related threads, the feedback you got from @spezwend and myself was that the problem persisted. Including measurement results and test descriptions.

Now instead of continuing working with us to a solution, having been provided proper feedback of the testing, the message was that PS Audio is not able to reproduce the errors. Which indeed is odd, I agree on that.

After having sent several reminders with requests to pursue this issue further resulted in the final word that PS Audio did not see another reason to pursue this further.

Conclusion for those affected is that the problem is not solved.

So this new complaint about the same well documented issue should not come as a surprise.

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This is completely different story. We are talking about selecting source/switching inputs, how do you do that when the preamp is powered down? :open_mouth: BTW, mute does not change anything, this was the first thing I tried.

Wow… looks like I’ve hit a nerve with this thread. Sorry. :flushed:

PS Audio has acknowledged a thump with some units when you switch to HT bypass. What is odd is @jhsg’s report his BHK250 enters fault/standby mode when switching to HT bypass. I do not recall anyone previously reporting this.

No problem! The forum is here to discuss issues. At times emotions run high.

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Full day of testing today. Importantly, when it’s working it sounds good.

When I switch everything off and switch it back on the bhk250 is fine. There’s a little thump but the bhk250 stays in its normal operating mode. However if I listen to music for an extended period and then switch to HT bypass - the bhk250 goes straight into fault mode. :confused:

People seem to be getting excited about the thump. That’s not really an issue for me as it’s minor and doesn’t worry me. The bhk250 going into fault mode is my concern.

I have tried muting the GCD - turning off my DSD before switching it over and I’ve also tried changing cables. Nothing seems to fix the issue. :frowning:

Sent an email to Ps audio support last night. No response yet. Will let everyone know once I hear back.

Thank you for the further information.

I am looking forward to your update after you work with PS Audio.

Let’s clear things out, not some units! I have tried many units in Europe, and some people who use HT bypass, all have problems. Most SGCD users do not use this feature! The bigger your speakers/subwoofers, the bigger the thump and problem. I would like to see Paul’s face when the SGCD is connected to IRS V and then switched to HT-Bypass. :slight_smile:

This thread is not about thumps, but @jhsg’s report his BHK250 enters fault/standby mode when switching to HT bypass. As he states the thump is “not really an issue for me as it’s minor and doesn’t worry me.”

Maybe not, but the issue is the same. It will go to fault mode when it receive’s a lot of DC voltage and that’s why @jhsg don’t head a loud th*mp. M700 don’t go into fault mode.

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Got it. That’s odd. The behavior is that of something discharging. Odd that it still happens on Mute – IDK how the SGCD handles muting, but the BHK uses a relay to disconnect the outputs on zero volume / mute / power down; so i can only imagine some kind of capacitance built up between that null connection and the amp. You’ve tried different cables? XLR vs SE, etc?