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EdisonRex
Site Admin
Joined: Mar 07, 2007 Posts: 4579 Location: London, UK
Audio files: 172
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Posted: Wed Jun 24, 2009 4:26 pm Post subject:
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to the forums Urosh. That is a very interesting and thoughtful post. I will try out your tests. I might even post the results here If someone else doesn't do it first. _________________ Garret: It's so retro.
EGM: What does retro mean to you?
Parker: Like, old and outdated.
Home,My Studio,and another view |
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torsig1967
Joined: Mar 29, 2006 Posts: 162 Location: Sweden
Audio files: 2
G2 patch files: 1
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Posted: Sun Jun 28, 2009 1:35 pm Post subject:
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recnsci wrote: |
Hi there,
IMHO reason is not poor or cheap circuit design, it's one of side effects of using DCO ... |
Interesting reading. Seems like there's no easy way to recreate old analogue oscillators using modern stuff like DCO then. In my opinion the whole point of using analogue oscillators is lost if there are artefacts like this (cheap or not).
How is this solved in the modern Moogs? |
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recnsci
Joined: Jun 24, 2009 Posts: 4 Location: Belgrade
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Posted: Mon Jun 29, 2009 11:57 am Post subject:
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torsig1967 wrote: | recnsci wrote: |
Hi there,
IMHO reason is not poor or cheap circuit design, it's one of side effects of using DCO ... |
Interesting reading. Seems like there's no easy way to recreate old analogue oscillators using modern stuff like DCO then. In my opinion the whole point of using analogue oscillators is lost if there are artefacts like this (cheap or not).
How is this solved in the modern Moogs? |
Sorry, I wasn't clear enough. "Cheapness" of DCO versus VCO is more historical reason. Today, it is not much more expensive to make true VCO synth, compared to DCO approach. Dave Smith, on the other hand, was forced to use DCOs because he uses custom manufactured CEM chips (AFAIK). Heart of evolvers and pro08s are chips similar to CEM 3396, used in Matrix 6 and Matrix 1000. "Waveshaper" part in those chips is analog portion of DCO.
And, AFAIK new Moogs use VCOs, as well as Andromeda and all SE synths. Probably cheapest VCO synth is that semi modular tabletop from MFB (KRAFTZWERG). You should check that one if you can.
cheerz
urosh |
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torsig1967
Joined: Mar 29, 2006 Posts: 162 Location: Sweden
Audio files: 2
G2 patch files: 1
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Posted: Tue Jun 30, 2009 2:52 pm Post subject:
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recnsci wrote: | Probably cheapest VCO synth is that semi modular tabletop from MFB (KRAFTZWERG). You should check that one if you can. |
There are some other MFB synths (Synth II, Synth Lite II e.t.c.) are these VCO as well?
Thanks for the info anyhow. |
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recnsci
Joined: Jun 24, 2009 Posts: 4 Location: Belgrade
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Posted: Thu Jul 02, 2009 3:14 am Post subject:
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torsig1967 wrote: | recnsci wrote: | Probably cheapest VCO synth is that semi modular tabletop from MFB (KRAFTZWERG). You should check that one if you can. |
There are some other MFB synths (Synth II, Synth Lite II e.t.c.) are these VCO as well?
Thanks for the info anyhow. |
As far as I know, only Kraftzwerg and Eurorack modules are VCO based. You should check this as well: http://www.spectralaudio.ch/neptuneII.htm .
Or, simply shop here: http://www.schneidersbuero.de/
(owner, Andreas Schneider, is one hell of a great guy). They have quite an extensive catalog.
cheerz
Urosh |
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Munchausen
Joined: Jun 18, 2009 Posts: 3 Location: PA
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Posted: Sun Jul 05, 2009 3:29 am Post subject:
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Urosh,
Please send your message to DSI support. You seem quite knowledgable about it and maybe they could tell you if an update would actually be possible. _________________ DSI MEK |
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gd
Joined: Jul 02, 2009 Posts: 16 Location: Canada
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Posted: Mon Jul 06, 2009 7:02 am Post subject:
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I agree with the above assessment as the P 08 suffers from the same so it must be due to the nature of the DCO's vs. the VCO. |
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Jinsai
Joined: Nov 19, 2005 Posts: 2 Location: San Francisco, CA
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Barely
Joined: Jul 07, 2011 Posts: 3 Location: somewhere else
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Posted: Thu Jul 07, 2011 3:05 am Post subject:
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recnsci wrote: | torsig1967 wrote: |
Seems they are well aware of the problem.
So I got myself a Novation Super Bass Station instead (analog too) and it's quite funny (or annoying) but this machine has a similar problem but less noticeable.
None of my truly vintage analog synths (MicroMoog, Korg MP, Pro One and others) has this artefact. So it has nothing to do with being "vintage" or being "analog". It's just poor and cheap circuit design. |
Hi there,
IMHO reason is not poor or cheap circuit design, it's one of side effects of using DCO (whitch Bassstation uses as well).
Classical VCO has circuit that converts voltage into current, and that current charges capacitor, which results in linear rise of capacitor voltage. When voltage reaches some threshold, electronic switch of some sort is triggered that discharges capacitor. Thus, you have sawtooth waveform on capacitor with constant amplitude, but with ramp rise rate (and thus VCO frequency) proportional to capacitor current. Problem is (among other things) that you need high quality voltage to current converter at VCO input, which means its expensive and a bit trickie to do.
(...)
Urosh |
Hi there and sorry for digging out such an old post.
I can hear the Oscillator clicking, yes.
But might I just draw your attention to this little song:
http://www.youtube.com/watch?v=RyLmV1yQJFg&feature=related
It's the almighty ARP2600, and it clicks as hell.
I actually like it that way So I'd say that the evolver is in best company sonically |
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Antimon
Joined: Jan 18, 2005 Posts: 4145 Location: Sweden
Audio files: 371
G2 patch files: 100
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Posted: Thu Jul 07, 2011 3:23 am Post subject:
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If you mean the faint sequence that opens the sound, that sounds like common clicks due to a steep attack to me. The noise you get on an Evolver is due to the pitch gliding, and is only apparent when you play two successive notes that have a large difference in pitch.
Another synth where this does appear though, is the Arturia Origin bafflingly enough. I've reported it here:
http://www.arturia.com/evolution/smf/forums.html?topic=3794.0
I can't for the life of me understand how someone could recreate this problem on a VA...
/Stefan _________________ Antimon's Window
@soundcloud @Flattr home - you can't explain music |
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Barely
Joined: Jul 07, 2011 Posts: 3 Location: somewhere else
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Posted: Thu Jul 07, 2011 3:55 am Post subject:
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Antimon wrote: | If you mean the faint sequence that opens the sound, that sounds like common clicks due to a steep attack to me. The noise you get on an Evolver is due to the pitch gliding, and is only apparent when you play two successive notes that have a large difference in pitch.
Another synth where this does appear though, is the Arturia Origin bafflingly enough. I've reported it here:
http://www.arturia.com/evolution/smf/forums.html?topic=3794.0
I can't for the life of me understand how someone could recreate this problem on a VA...
/Stefan |
Yeah, now I hear the difference, too. I couldn't reproduce it so quickly on my PEK. Maybe it's because the phase is started again at a new key press, and the oscillator has trouble finding the right phase AND frequency? Just a guess...
Besides that, how do you like your Origin? I stalked around one for some time and then decided to buy a Virus. Which is much better than I expected, btw... |
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Antimon
Joined: Jan 18, 2005 Posts: 4145 Location: Sweden
Audio files: 371
G2 patch files: 100
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Posted: Thu Jul 07, 2011 4:17 am Post subject:
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The Origin is ok, I guess. I just think that the whole VA deal isn't for me - too often I struggle to make it sound anything else than bland. I was hoping that the Origin would be the polysynth with classic-like structure that fills a space between the PEK and the Nord Modular G2 Engine.
The hardware interface on the Origine is nice. I see it as a template machine - you use (and occasinally make) ready-made structures that are tweakable if you feel the need. Being accustomed to the Nord Modular I don't see the Origin as something you patch from scratch a lot - too cumbersome. _________________ Antimon's Window
@soundcloud @Flattr home - you can't explain music |
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BobTheDog
Joined: Feb 28, 2005 Posts: 4044 Location: England
Audio files: 32
G2 patch files: 15
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Posted: Thu Jul 07, 2011 4:41 am Post subject:
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I quite like patching the Origin.
I think it is because it is fairly simple, there are not that many modules to complicate things. Whereas the G2 makes my mind boggle and steam start appearing form my ears!
I find it easy to make the Origin sound good (to my ears) while I find it very hard to make the G2 sound good, although I know that people here with a bit more savvy than me make exceedingly good sounding G2 patches, if only I could understand them! |
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Pym
Joined: Apr 13, 2010 Posts: 2 Location: San Francisco
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Posted: Fri Jul 08, 2011 7:01 pm Post subject:
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On page 7 of the 3396 preliminary data sheet (link: http://www.synthtech.com/cem/c3396pdf.pdf) you'll read about range of the oscillator and describing how the chip has a practical range of about 6 octaves with a reasonable error rate. To increase this range it's advisable to use a second resistor to switch over when the range goes from the low to high registers. That's probably what you're hearing. In most instruments using these chips and similar ones the total response time of the voice (envelopes, filters, etc) is pretty slow and thus masks small artifacts like this one. In our gear we err on the side of responsiveness, the envelopes and filter response are extremely quick, with the downside that you hear some artifacts that are naturally inherent in the analog circuitry. It's always a matter of compromise with things like this. |
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Barely
Joined: Jul 07, 2011 Posts: 3 Location: somewhere else
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Posted: Sat Jul 09, 2011 3:07 am Post subject:
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Pym wrote: | On page 7 of the 3396 preliminary data sheet (link: http://www.synthtech.com/cem/c3396pdf.pdf) you'll read about range of the oscillator and describing how the chip has a practical range of about 6 octaves with a reasonable error rate. To increase this range it's advisable to use a second resistor to switch over when the range goes from the low to high registers. That's probably what you're hearing. In most instruments using these chips and similar ones the total response time of the voice (envelopes, filters, etc) is pretty slow and thus masks small artifacts like this one. In our gear we err on the side of responsiveness, the envelopes and filter response are extremely quick, with the downside that you hear some artifacts that are naturally inherent in the analog circuitry. It's always a matter of compromise with things like this. |
That is the most precise answer we will ever hear about this Thanks for digging that up! Still, I don't find it too terribly bad, I still love my PEK *pat pat* Now I have the sudden urge to test my other analogues on second resistor switches |
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recnsci
Joined: Jun 24, 2009 Posts: 4 Location: Belgrade
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Posted: Fri Jul 15, 2011 2:03 am Post subject:
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Hi Pym, thank you for your response.
...
I have few questions (if OP doesn't mind a bit of hijack). First, if it's not trade secret, what is sample rate of control signals in Evolver (that is, sample rate of DACs that generate Cutoff, Resonance, Pulsewidth, etc Control Voltages) and what is their resolution (in bits)? Second thing, should we expect adding few bits and pieces in firmware, or development of Evo FW has reached it's final phase? I'm interested in just two things, adding signal just after VCA and before Pan as mod source and adding feedback level as mod destination.
Best Regards |
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littletinymonkey
Joined: Dec 11, 2018 Posts: 1 Location: USA
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Posted: Tue Dec 11, 2018 8:12 am Post subject:
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I am new to the Evolver and spent way to much time trying to track down what I was doing wrong before learning that this issue was more widespread than just my "new to me" unit.
I guess for future internet travelers, here's how I was able to recreate this problem reliably using a different method than what is discussed and by playing the same note over and over.
1. I created an init preset from page 8 of Anu Kirk's 'Definitive Guide To Evolver'.
2. I ensured that my Key Off/Xpose was set to Zero.
3. I copied the init preset that I just created to a neighboring slot so that I could easily toggle between the two identical presets.
4. Turn the program knob to change to one (or the other) of the init presets.
5. Press a key on my MIDI controller and listen for the DCO and VCO not firing at the same time. Press the same key again (without changing programs) and everything sounds as expected.
6. Repeat 4 and 5 until sad because by now you've noticed the issue.
7. Sigh and be sad. |
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