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SEQUENTIAL/DSI => Tempest => Topic started by: vscomputer on October 24, 2016, 07:15:14 PM

Title: Keyboard sounds - partially bypassing filter?
Post by: vscomputer on October 24, 2016, 07:15:14 PM
Hi all!

I was messing with my Tempest this evening trying to make some sweepy pads.

I've got both my analog oscs turned on; both digital oscs are turned off. Filter frequency is set to 0, all Lowpass filters are set to 0.

Theoretically, I shouldn't hear any sound, right? I still hear the analog oscillators, unfiltered, at a very low level. If I tweak the filter knob or add any of the low pass envelopes, I hear the much louder "real" sound but it's always accompanied by this much quieter unfiltered sound.

It's particularly obvious when I add a lot of Attack time to the filter envelope trying to make big filter sweeps. My intention is for it to sound like "bwooOOOMMM" but instead it always goes "*tzzzzzz*bwoooOOMMM."

Is there something I'm missing or does some of the oscillator sound just always "get around" the lowpass filter and I just have to live with it? The unfiltered sound is affected by the amp envelope so I guess I could work around it using that but what a pain.

Warmest regards,
Vscomputer
Title: Re: Keyboard sounds - partially bypassing filter?
Post by: Yorgos Arabatzis on October 24, 2016, 11:52:59 PM
Do you have the feedback cranked up?
Title: Re: Keyboard sounds - partially bypassing filter?
Post by: muleskinner on October 25, 2016, 09:34:09 AM
Is the 'unfiltered' sound coming from the main outs?

I ask because I have noticed crosstalk on the main outs before - I'm not sure if it was pre or post filter though. It was particularly noticeable with compression cranked up (as you'd expect I guess).

I have also noticed you can hear one of the analog oscillators sometimes even if the osc mix it set completely the other way!

I always put this stuff down to the 'joy of analog'!
Title: Re: Keyboard sounds - partially bypassing filter?
Post by: vscomputer on October 25, 2016, 06:18:23 PM
Quote from: Yorgos Arabatzis
Do you have the feedback cranked up?
I do not. That's at zero.

Quote from: muleskinner
Is the 'unfiltered' sound coming from the main outs?
Yes. Compression and distortion are also at zero.

I also see now that this *only* happens with the analog oscs; the digital oscs do not exhibit this behavior.


Title: Re: Keyboard sounds - partially bypassing filter?
Post by: John the Savage on October 26, 2016, 02:34:30 AM
Quote from: Yorgos Arabatzis
Do you have the feedback cranked up?
I do not. That's at zero.

Quote from: muleskinner
Is the 'unfiltered' sound coming from the main outs?
Yes. Compression and distortion are also at zero.

I also see now that this *only* happens with the analog oscs; the digital oscs do not exhibit this behavior.

Are you using one of the factory projects by chance?  I'm asking because oscillator bleed does happen on the Tempest, but it's most noticeable when the compressor is cranked, and many of the factory projects are saved with heavy compression settings or the distortion engaged.  So you may be looking at the knobs and seeing that they're in the 'off' position, when in fact those effects are active.  Anyway, you might try turning the knobs to reset those two parameters just to be sure.

It should also be noted that the distortion and compression parameters can be saved for each individual beat as well, depending on your system settings; so you may have to reset them for every beat within the project.  And if you don't save these changes they will come back to haunt you every time you turn on the Tempest.

At any rate, here's hoping it's that simple, and not something actually wrong with your Tempest.  But again, oscillator bleed is not uncommon.  Sometimes it quits if you hit six or more pads at once and max-out the voice count... (shrug).

Cheers!
Title: Re: Keyboard sounds - partially bypassing filter?
Post by: Shea on October 31, 2016, 03:51:40 PM
i experience osc bleed as well. there's the bleed, the distortion pop, etc etc, but i just ignore it...

overall, there is a lot that needs to be done to hone the analog osc's, but once you do, i think the T is just as capable a poly as the P6. I've gotten all of the lush round warm tones I've ever wanted out of it after a year of trying.
Title: Re: Keyboard sounds - partially bypassing filter?
Post by: LucidSFX on October 31, 2016, 09:48:39 PM
What are those random pops when no distortion or compression is applied? Is that a cause of bad patch programming?