Well I haven't remembered that of Sanskrit (I did remove the SGM7310 a few times, not for beginners as said before) but with my SU-1 there is no problem except of course at power on/off. Contrary to general opinion I am absolutely not fond of semis for muting as they practically always have a detrimental influence on sound quality. Even worse is series switching so IN the signal path. Non linear parts for variable voltages, bleh. Remove them and hear the difference. If nothing is done expect power on/off plops of the annoying kind. Even if the SGM7310 would be the best one can find with most beautiful MOSFETs, stellar datasheet, approved by Mr. X etc. it still is prone to failure so it is a question of time before one has to do something.
Power on/off muting:
Relays shorting outputs to GND at power on/off are much better as they are not in the signal path. However that works only OK for power on/off plops. Retrofitting can be done with mini PCBs with micro relays on them and a simple timing circuit.
Bit error muting:
When playing CD I suspect bit errors to give plops when no semi muting its used. Practically never experienced those the past 20 years when playing files from an audio player.
Power on/off muting:
Relays shorting outputs to GND at power on/off are much better as they are not in the signal path. However that works only OK for power on/off plops. Retrofitting can be done with mini PCBs with micro relays on them and a simple timing circuit.
Bit error muting:
When playing CD I suspect bit errors to give plops when no semi muting its used. Practically never experienced those the past 20 years when playing files from an audio player.
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IMHO DC plops usually are a serious defect/imperfection. Sometimes they are just a negative experience that keeps returning. Allowing such daily returning and easily solved imperfections is a weakness. So IMHO it should be solved one way or another. Expecting a predefined power on/off sequence of stuff in a family or partnership situation is just madness. It is just 1 micro relay and a handful of parts with the bonus of better sound quality as well.
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DSD may cause loud thumps at start/stop unless muting is done correctly. This is due to using zero data as silence which in DSD playback results in DC. Don't know if SGM3710s in Sanskrit are used for this type of muting.
Never play DSD so never experienced that. Well it is dead anyway and replacing it for another one that may die is a possibility 🙂
Really if one thinks muting transistors already are a nuisance, this particular IC is a curse.
Really if one thinks muting transistors already are a nuisance, this particular IC is a curse.
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I don't do DSD either so no problem there but I would like to avoid injecting DC into my drivers via my DC coupled power amps... is there a risk of harming say a compression driver?
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Pssst! There are ingenious ways to solve that. Just 2 caps or the muting relay. Or both. What keeps you from retrofitting a tiny circuit?
No caps at all in a fully DC coupled situation is asking for trouble.
No caps at all in a fully DC coupled situation is asking for trouble.
CAPS - shure ;-D ... but no - I'd rather live on the dangerous side...
Is there a "slot-in-place" relay product?
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Is there a "slot-in-place" relay product?
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Many have regretted to omit the input caps in power amplifiers 🙂 The so-called "DC fuse"'.
No a member here sold tiny PCBs. Hardwired them too but dislike sloppy stuff. I would have to draw new ones in KiCAD. Maybe I will as my SU-1 needs it too, they would then have the smallest relays available.
Found them: https://www.diyaudio.com/community/...level-audio-output-delay-retrofit-pcb.358940/
No a member here sold tiny PCBs. Hardwired them too but dislike sloppy stuff. I would have to draw new ones in KiCAD. Maybe I will as my SU-1 needs it too, they would then have the smallest relays available.
Found them: https://www.diyaudio.com/community/...level-audio-output-delay-retrofit-pcb.358940/
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Hi, something like this. It is very small (27 x 19 mm) but it has an M3 mounting hole for sturdy mounting. It can be used for both unbalanced and balanced setups.
Motto is "1 M3 hole is no M3 hole" but it really is too tiny for 2 mounting holes 🙂
Motto is "1 M3 hole is no M3 hole" but it really is too tiny for 2 mounting holes 🙂
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We'll see. It is my SU-1 which does not resemble the original. I changed it a little as one M3 hole really is not OK. It is now 32 x 22 mm and uses 78xx as I replaced too many 78Lxx and also everyone has a few TO220 78xx. Relay is NAIS AGN series. The files are already sent to the PCB factory.
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I recommed Cambridge Audio Dacmagic Plus with Bluetooth dongle, I have it with a Cosel 12V industrial power supply. It works fine.
Now is DacMagic 200M on market but I haven't seen.
It's not in your scope budget, but I think there is not much more better alternatives.
Now is DacMagic 200M on market but I haven't seen.
It's not in your scope budget, but I think there is not much more better alternatives.
Could the SGM7310 control signal be used to control another circuit, that has less effect on the output sound?
Of course but then probably a transistor or small MOSFET is needed as well and ... it won't be fast enough for bit errors AFAIK. Since I am not into all details of current chips and do not care to know all the added bells and whistles I can not tell if these solve bit errors by internal muting. Maybe someone knowledgable knows. I only focussed on making a copy with added functionality of the muting circuit in the linked thread.
Worst of all generally are power on/off plops.
Worst of all generally are power on/off plops.
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Unfortunately, for some SMSL DACs (e.g. D300), if the files to be played are of different sample rates (44.1kHz/48kHz ...), a loud plop will be heard when playback starts if the output is not properly muted for the period.
I experienced the same phenomenon with the ESS9038Q2M chip.
I experienced the same phenomenon with the ESS9038Q2M chip.