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DSM01 VCA

chysn

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DSM01 VCA
« on: August 29, 2016, 08:10:11 PM »
The DSM01's input is not DC-coupled, which means that it doesn't really work well as a VCA for CV. For most practical purposes, it's an audio VCA. Its value is that it frees up other VCAs that are DC-coupled. For this reason, almost all of my patches make their way to the DSM01 eventually, even if I'm using other filters.

However, it's worth noting that the Make Noise LxD low pass gate does have DC-coupled inputs. When designing modules, I think it's important to consider CV, even if you think it's a module for processing audio. One of the important strengths of modular synthesis is the interchangeability of audio and control, and my opinion is that an AC-coupled input was a design mistake for the DSM01, due to the fact that it does have a built-in VCA.
DSI: DSM03; previously: Mopho Keyboard, Desktop Mopho, Evolver, DSM01
Hardware: Eurorack, Moog Little Phatty w/ CV Outs, Arturia MicroBrute, KMI QuNexus
Software: macOS, Ableton, MuseScore
Modular Grid: https://www.modulargrid.net/e/racks/view/354385
GitHub: https://github.com/chysn

Steven Morris

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Re: DSM01 VCA
« Reply #1 on: September 03, 2016, 01:46:58 AM »
When designing modules, I think it's important to consider CV, even if you think it's a module for processing audio. One of the important strengths of modular synthesis is the interchangeability of audio and control, and my opinion is that an AC-coupled input was a design mistake for the DSM01, due to the fact that it does have a built-in VCA.

You have made a very important point. I love modular for the fact that I can patch things that are not standard, so I like to choose my modules accordingly.

In other words, I agree with you 100%!

chysn

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Re: DSM01 VCA
« Reply #2 on: September 03, 2016, 05:13:02 PM »
Don't get me wrong. My system is only 144HP, so if I didn't think the DSM01 was worth 8HP, it would be off the team. Not only is it a filter sound that I want, I value the audio VCA quite a bit.

But I've noticed that with eurorack companies, there's a two-way dialogue between the musicians and the company. For example, the original Intellijel Triatt was just a three-channel attenuator. After feedback from the eurorack community, the designer added a DC-coupled mixer function to future Triatts. I've got several such examples, but the point is that there's a lot of agility.

If DSI had solicited feedback from the eurorack community prior to releasing the DSM01, somebody would have said, "Is that input DC-coupled so we can use the VCA for CV? If not, why not?" There would have been no reasonable answer for "why not?" so I think it wasn't even considered.

So my main point here isn't that the DSM01 is no good, because it damn well is. My point is: if you want to make eurorack modules, knowing that you don't have tons of experience with it, get the target users to give you some free ideas. We love to talk about this stuff.

DSI does seem a little secretive. Even as the DSM03 is going into production, we can't wrench out any information about its LPF. Any other company, they'd be bragging about it, getting everyone excited about it.  Now that I've seen how other companies communicate, DSI seems a little off.
« Last Edit: September 03, 2016, 05:18:54 PM by chysn »
DSI: DSM03; previously: Mopho Keyboard, Desktop Mopho, Evolver, DSM01
Hardware: Eurorack, Moog Little Phatty w/ CV Outs, Arturia MicroBrute, KMI QuNexus
Software: macOS, Ableton, MuseScore
Modular Grid: https://www.modulargrid.net/e/racks/view/354385
GitHub: https://github.com/chysn

Steven Morris

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Re: DSM01 VCA
« Reply #3 on: September 04, 2016, 12:54:52 PM »
I understand what you mean, and I don't doubt that it is a great module. Regarding your point about user-feedback during the development stage (and subsequently after production, looking forward to v2 modules), it seems like something that smaller companies can get away with in smaller communities... and it's something that DSI have seemed to shy away from AFAIK.

I think this is for good reason as well. Often Dave Smith will talk about how he doesn't like the idea of having too many features thrown onto one instrument-- the kind of thing that happens when you hire (or simply ask) a group of too many people to help you come up with ideas. That kind of thing takes away from the original design idea and often hinders the ergonomics of a design.

At any rate, I think that the module could have benefited greatly with the feature that you suggested and it's not really a feature inasmuch as it is a standard in terms of Eurorack. Again though, I think the whole idea of the built-in VCA, as you said in your OP, is that 'its value is that it frees up other VCAs that are DC-coupled'.

Re: DSM01 VCA
« Reply #4 on: September 04, 2016, 03:24:31 PM »
Maybe there is something about the filter itself as a synthesis tool or signal-path component that lends a nod to other things that are coming down the pike - after all, the SSM- and SEM-style filters in the Pro-2 certainly point toward the Prophet-6 and OB-6, and, there is always something new in each DSI product....
Sequential / DSI / Pioneer stuff: Prophet-12 desktop, Pro-2, AS-1, Prophet-600 Gligli, Prophet 2000

chysn

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Re: DSM01 VCA
« Reply #5 on: September 04, 2016, 03:38:56 PM »
Maybe there is something about the filter itself as a synthesis tool or signal-path component that lends a nod to other things that are coming down the pike - after all, the SSM- and SEM-style filters in the Pro-2 certainly point toward the Prophet-6 and OB-6, and, there is always something new in each DSI product....

I think that's reasonable. The filter is apparently a new design, and I very much doubt that they'd design a new filter for use only in a eurorack module.

However, it also wouldn't make much sense to just jam any old filter into a feedback module. Lowpass filters are pretty ubiquitous in euro systems, so a random filter--no matter what it is--wouldn't be much of a selling point. There has to be some design motivation to including a specific filter. A vactrol-based filter would have been a great match for a feedback module, especially one geared toward Karplus-Strong synthesis. Anticipating the DSM03, I bought a lowpass gate for exactly this reason; the slower response time of vactrols will lend a nice, organic sound to a plucked-string or struck-surface sort of signal.
DSI: DSM03; previously: Mopho Keyboard, Desktop Mopho, Evolver, DSM01
Hardware: Eurorack, Moog Little Phatty w/ CV Outs, Arturia MicroBrute, KMI QuNexus
Software: macOS, Ableton, MuseScore
Modular Grid: https://www.modulargrid.net/e/racks/view/354385
GitHub: https://github.com/chysn