Moog Subsequent 37 noise when keys played/envelopes are opened but no Oscillators on/up

[sandy555]

Hi, firstly please excuse me if my question is a bit newbie.
I have my first hardware analogue synth (given ive only ever used software to date) - Moog Subsequent 37.
I noticed on headphones a high frequency noise (like a low level noise generator of sorts) that is audible when playing notes on the keyboard but without any oscillators on or up (and definitely no resonance or anything else active to afford self generation etc)
I've looked online and i think this phenomena is universal to this product and some other analogue synths.
Defiantly not a earthing or ground loop matter as its only evident when the amp envelope is triggered otherwise silent.
However, I thought id double check as its a little bit annoying on a couple of patches ive heard to date.
That said, I appreciate headphone monitoring is as about as immediate as you can get and whilst there in the line out, its not so apparent listening through speaker monitors and is low level in terms of metering.
The other 'issue' is a clicking sound again that is audible when keys played with no oscillators on (that is low frequency) - i appreciate this can be remedied by affording some attack and release time which i understand allows some ramp to negate the waveform cycles falling at non zero crossing points? - that im sure is normal as this is the case with VI synths ive used and standard science as i understand it. Just interesting it is being generated with no oscillators on or up again.
Ultimately I understand the amp envelopes act kinda like a gate to 'open' and hear the sound but its just a bit confusing re the high frequency noise aspect in particular with this given no oscillators are on or up....? maybe its impossible to actually completely switch them off in a pure analogue synth and some signal will always be leaked and heard when triggering the amp envelopes such as this or maybe its the envelope circuits themselves generating the sounds post the oscillators ?

Just thought id ask for peace of mind given the forum info ive found elsewhere doesn't completely or clearly define although others have asked about it with the product.....

[The Elf]

I would definitely expect *some* noise through the envelope with oscillators turned down. As to how much and of what nature... that's down to the electronics.

[Hugh Robjohns]

I have a Subsequent 37cv. I've not noticed the noises you describe, but then I dont play it with the oscillators turned off!

I would expect some very low level digital control noise, though — it's pretty much inevitable. ADSRs will often generate clicks and thumps, especially at very fast settings.

I'll fire mine up tomorrow and check out your findings... but I suspect what you're hearing us entirely normal for an analogue synth. Virtual synths can be made to behave with theoretical perfection; analogue synths cannot!

[skipper01]

I had some weird issues with noise with my sub37 but mine was faulty and not these

[sandy555]

I'd be very grateful if you could have a listen Hugh.
Its kinda like white noise ish on all patches and init patch.
Perhaps init a patch and switch off all the 5 buttons in the mixer for the oscillators/generators, press a key and listen on cans.
I've set my output to max and headphones to around 7 to test with my headphones and its there for sure.
Others online in a few places have asked both this but there's no definitive answer.
Maybe a facet of the instrument and nothing to worry about.
Thanks in advance

[Hugh Robjohns]

If it didn't hiss a bit with the headphones on max it would be broken. All audio electronics generate noise — white noise. This is normal... but I'll try and get some figures from mine tomorrow for comparative purposes.

[Arpangel]

I have my first hardware analogue synth (given ive only ever used software to date)

Welcome to the lovely world of analogue.
Without noise I'd think it was dead, noise is comforting, it assures you all is well, noise in analogue hardware is the sound of it "breathing" that it's alive.

[sandy555]

It was just I could hear it on a couple of patches even when an oscillator or oscillators were on and then heard/traced it to being in isolation only when keys are pressed.
That made me question whether it’s normal for that instrument or even others?
I’ve heard a noise floor across everything but this is just when keys are pressed and is quite a specific noise at that following the amp env stage settings.
I’ll be interested to hear if others are the same.
I appreciate headphone monitoring is very immediate…!