Nasty artifacts ...in signal path

The Cherry Audio CA2600 is a powerful, self-contained duophonic synthesizer inspired by the groundbreaking ARP 2600 synthesizer.
gentleclockdivider
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Re: Nasty artifacts ...oscillators

Post by gentleclockdivider »

Can a developer chime in and aknowledge the issue ,and if they will do something about it .?
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cherryaudio Greg
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Re: Nasty artifacts ...in signal path

Post by cherryaudio Greg »

Hi,

Thanks for your feedback, I'll pass it along!

Greg
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cherryaudio Greg
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Re: Nasty artifacts ...in signal path

Post by cherryaudio Greg »

Hi again,

Can you please send us a preset that demonstrates this issue?

Greg
gentleclockdivider
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Re: Nasty artifacts ...in signal path

Post by gentleclockdivider »

cherryaudio Greg wrote: Wed Nov 11, 2020 9:51 pm Hi again,

Can you please send us a preset that demonstrates this issue?

Greg
Serious , I reported bugs in detail not only on this forum but also on kvr audio , pictures + sound
It's all documented in this thread , routing a sine osc ( set to low freq ) or an lfo straight to the vca output ommiting the filter , the overtones are at 4Khz, 8Khz etcc

Set host to 44.1 Khz
And here 's an example of how it's perceivable in a musical context , 3 squares low pass fitered , once the higher harmonics are filtered out , the nasty tones are audible
P.s. I have an exceptional good hearing , which might explain why other people don't hear it
Attachments
3 squares.rar
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cherry .rar
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Last edited by gentleclockdivider on Wed Nov 11, 2020 10:09 pm, edited 1 time in total.
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cherryaudio Greg
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Re: Nasty artifacts ...in signal path

Post by cherryaudio Greg »

Hi,

Thanks for those presets.

Greg
Steve W
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Re: Nasty artifacts ...in signal path

Post by Steve W »

I have high frequency hearing loss but heard a low frequency rumble coming from the LFO set at an audible frequency that seems to be piped into the mixer. Is that one of the nasty artifacts?

EDIT: That one is ugly 2. The low frequency sound in ugly 1 seems to be coming from Initial Freq for Osc. 3.
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2020-11-11 CA2600 LFO.png
2020-11-11 CA2600 LFO.png (757.3 KiB) Viewed 3266 times
gentleclockdivider
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Re: Nasty artifacts ...in signal path

Post by gentleclockdivider »

No , that low frequency rumble is the LFO (it's supposed to be low :) , look at the provided screenshots for the artifacts (5 Kilohertz range ) , if you have high frequency hearing loss ...good for you ;)
It's not just the osc's and lfo's but literally anything you route directly to the vca output ,always at the same frequency .
Just route modwheel to vca out and modulate it ..same stuff

Reason why I posted the sine osc and lfo examples is becasue these are the most .
Sure , the lfo to vca out routing is not something we use in a musical context ( unless you want to make music for elephants ) , but even when filtering a saw or square , those frequencies are still there ., even when all harmonics of the waves are filtered out .
Is it becasue of a downsampling process , as someone said it runs natively at 48Khz ..and 44Khz brings out the artifacts , maybe .
polyandy
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Re: Nasty artifacts ...in signal path

Post by polyandy »

So here is an example of what sounds so wrong to me, also with the recent update. I'm using the latest Logic and UAD Apollo Twin (I don't even know if that matters). The first example is at 96 kHz and the second example is at 88.2 kHz. 88.2 and 44.1 both have the ugly harmonics, while 96 and 48 sound fine.

https://www.dropbox.com/s/47ed8t9t0qqpu ... t.aif?dl=0
gentleclockdivider
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Re: Nasty artifacts ...in signal path

Post by gentleclockdivider »

There is clearly aliasing in the last audio part ( 44 k )
Not sure if this has anything to do with the ugly harmonics I have mentioned
ColinP
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Re: Nasty artifacts ...in signal path

Post by ColinP »

OK, so if it sounds fine at 48 and 96 then almost certainly the native sample rate is 48 kHz and the artifacts you dislike are caused by re-sampling.

High quality interpolation is computationally quite expensive so I imagine CA are using something that's not top-of-the-range as a trade off so that it still has reasonable performance on modest horsepower computers, which seems completely reasonable to me.

Is there some reason why you can't operate at 48 kHz?

If you need to change the sample rate for mastering then perhaps you could record live work at 48 kHz and then apply third party re-sampling off-line that uses state-of-the-art interpolation in order to achieve the pristine results you are after.
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