Horrible aliasing

The Cherry Audio CA2600 is a powerful, self-contained duophonic synthesizer inspired by the groundbreaking ARP 2600 synthesizer.
andro
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Re: Horrible aliasing

Post by andro » Sat Dec 05, 2020 1:34 pm

cherryaudio Greg wrote:
Tue Nov 24, 2020 11:16 pm
I suspect that your definition of "horrible aliasing" and theirs might differ.
I think aliasing is by definition horrible without the adjective.

I am writing some generator modules now and it takes an advanced knowledge of DSP (and a huge amount of work) to prevent oscillators from aliasing, which I regard as a primal sin. And indeed, as per the OP, I suspect many people do not have trained ears that can hear this junk for what it is and think it's some fat, desirable analog sound.

An example from the outside world is Bazille from u-he which I love in concept, but it has never been updated and aliases so badly all over the place that to me it is unusable as a synth. I think it was just an initial experiment.

Hoping you can fix it.

Andrew

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cherryaudio Greg
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Re: Horrible aliasing

Post by cherryaudio Greg » Sat Dec 05, 2020 7:50 pm

Hi,

Check out the next update, which should be ready within a week or two.

Greg

gentleclockdivider
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Re: Horrible aliasing

Post by gentleclockdivider » Fri Dec 11, 2020 10:14 am

Latest update installed
Osc sync aliasing issue is still there

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cherryaudio Greg
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Re: Horrible aliasing

Post by cherryaudio Greg » Fri Dec 11, 2020 11:01 pm

gentleclockdivider wrote:
Fri Dec 11, 2020 10:14 am
Latest update installed
Osc sync aliasing issue is still there
Hi,

What's the maximum modulation you're doing with TAL Mod? What's the range you're doing with CA2600?

Greg

gentleclockdivider
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Re: Horrible aliasing

Post by gentleclockdivider » Fri Dec 11, 2020 11:35 pm

Exactly the same as shown in the first post
I am not using any modulation at all , but just playing higher registers .
Sync slave osc is two octaves above the sync master ( both saw waves ) , now play higher notes and you hear the aliasing .
But even when both are the same it still happens
Modulation makes it worse

Here's another file , Sync master and slave have the same pitch , I will play the c for 4 octaves starting from c4
First part is cherry , second part is talmod ( talmod is clean as a whistle )
You can easily test this yourself since talmod has a demo version ( don't forget to set the subosc which is the syncmaster to +12 semitones , since it is tuned one octave below the others osc's )

https://app.box.com/s/eqgt2lafvdcbymlb6qwcdd1bg5kgtkxp

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haslo
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Re: Horrible aliasing

Post by haslo » Tue Dec 15, 2020 12:46 pm

Have you actualy upgraded? I tried to reproduce your results (hosted in Ableton 10 on Mac), and while my current CA2600 version still has more aliasing than the Talmod sample you provided, it's also much better than your CA2600 sample, and it also benefits from a higher host sampling rate (96k are much cleaner than 44.1k).

Edit, here's spectrograms of all three: https://photos.google.com/share/AF1QipM ... FrdGhIVE53

Edit: I've added a fourth image, which is the CA2600's oscillator without that sync, which produces absolutely no aliasing at 44.1k (just like Talmod, so the two pictures look almost identical). I also noticed that I hadn't switched off the reverb before, so the previous CA2600 images would be cleaner, too.

gentleclockdivider
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Re: Horrible aliasing

Post by gentleclockdivider » Wed Dec 30, 2020 12:55 pm

Just a saw ( osc 3 ) set to 2' or 4"' , synced to osc 2 (set to 16') makes it alias .
No rocket science
Result is and remains horrible
Changing internal sample rate to 96 Khz to reduce the aliasing simply proves it's bad dsp coding from the start .
It is what separates the good ones like talmod , u-he , cytomic , synapse audio which operate perfectly at 44khz from the bad ones ( cherry )

gentleclockdivider
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Re: Horrible aliasing

Post by gentleclockdivider » Thu Jan 07, 2021 1:06 am

Bump
Still waiting for better osc's when synced

gentleclockdivider
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Re: Horrible aliasing

Post by gentleclockdivider » Wed Feb 03, 2021 12:20 pm

One month later ..still nothing
Great company :mrgreen:

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cherryaudio Greg
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Re: Horrible aliasing

Post by cherryaudio Greg » Sat Feb 06, 2021 10:03 pm

Hi,

Sorry I don't have an immediate solution for you. The issue was brought to the attention of the software developers and there hasn't been an update, unlike the prompt updates we added for the other couple of issues that you reported here and on other forums. I guess just avoid using super high frequencies with synched oscillators if you don't like the way it sounds?

Greg

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