Anyone with a SCI Pro One?

[Urs]

Hey,

We're looking for people who call a Pro One their own and we'd like you to create a little audio file for us. It's nothing dramatic, just the raw filter self oscillation and the raw waveforms (including hards witching them on and off via the switches). We're not so much interested in the waveforms themselves, but merely in what happens in the moment of the switch, their volume relation and how the pitch/drive of self oscillation changes when resonance reaches max level.

Here's a little video we made with our own:



It'd be great to get an audio file (.wav at 44.1kHz would be sufficient) sent to us via WeTransfer, Dropbox or similar. The email is support at u-he dot com and the file should contain audio of the settings shown in this video:

Prepare: Set everything to zero, just OSC A/B fully up in mixer, pulsewidth to 50% and Volume/Sustain to a reasonable level.

1. High resonance filter cutoff sweep from lowest position to about 1kHz.
2. Slowly lower resonance until self oscillation stops, then slowly bring resonance fully up again
3. With filter fully open resonance 0, switch all waveforms and wavefom combinations on and off for each oscillator

The actual pitch of the oscillators doesn't matter, but Osc B shouldn't be in LO FREQ setting

We would expect some "wobbling" once a waveform is switched on. And we would expect a slight change of filter frequency from start of self oscillation till full resonance. Please do not alter the volume during any of these settings (that would defy the purpose, hehehe).

I hope this isn't too much hassle & thank you so much for your help,

- Urs

[aaron aardvark]

Urs,
I'm willing to help, but my Pro-One is not in pristine audio condition. There is a significant amount of unpleasant noise whenever it is being played. I would only use my Pro-One in a music recording if I put its output into a Line 6 PodXT amp modeler to add guitar amp distortion to cover up its unwanted noise. I could post a song with it (mostly with French competitor synths). By the way, have you ever considered adding a wah-wah effect on any of your synths? The song I was talking about uses Pro-One>PodXT>Cry Baby wah wah pedal. I have a Korg synth with a wah effect. Still interested in my marginal Pro-One?

[aaron aardvark]

oops, double post.

[Urs]

Hey Aaron,

Any Pro One is welcome. Freshly serviced ones as well as ones in need of such.

We're interested in bandwidth, i.e. "how different are two Pro Ones next to each other?"

Thanks,

- U

[Stupid American Pig]

Sounds like you have your worst case above! does this mean we are going to see a Pro-One Clone sometime soon?

[Urs]

Sounds like you have your worst case above! does this mean we are going to see a Pro-One Clone sometime soon?

Check our forum... there's a thread about something called RePro-1

[aaron aardvark]

Urs,
I'm still getting my act together with recording the Pro-One. It is being way less noisy for some reason, the best it has sounded in over 20 years! I turned it upside-down to dust it off and heard something rattling around inside. Not sure if that fixed it. On a probably unrelated note, did you know the (single female) output on the Pro-One is in stereo? It only took me over 34 years to notice that! Even though it's right in the instruction manual! For years I recorded on a 4 track cassette deck and tracks were at a premium in the 80's, and recorded the Pro-One in mono every time. And my keyboard amp (circa 1983) is in mono. I should have noticed how different it sounded with headphones earlier.

[aaron aardvark]

Urs,
I sent an audio file through Dropbox to u-he. In stereo, if that makes any difference in this case.

[bsterz]

Are you still looking for input? I have a later serial number unit that will likely work (dreaded membrane keybed)

I'm unaware of any component or circuit changes in the versions though. Feasibly, the age of the components is a bit different - but at this point... that's a rounding error in the big picture.

[zerocrossing]

Hey,

We're looking for people who call a Pro One their own and we'd like you to create a little audio file for us. It's nothing dramatic, just the raw filter self oscillation and the raw waveforms (including hards witching them on and off via the switches). We're not so much interested in the waveforms themselves, but merely in what happens in the moment of the switch, their volume relation and how the pitch/drive of self oscillation changes when resonance reaches max level.

Here's a little video we made with our own:



It'd be great to get an audio file (.wav at 44.1kHz would be sufficient) sent to us via WeTransfer, Dropbox or similar. The email is support at u-he dot com and the file should contain audio of the settings shown in this video:

Prepare: Set everything to zero, just OSC A/B fully up in mixer, pulsewidth to 50% and Volume/Sustain to a reasonable level.

1. High resonance filter cutoff sweep from lowest position to about 1kHz.
2. Slowly lower resonance until self oscillation stops, then slowly bring resonance fully up again
3. With filter fully open resonance 0, switch all waveforms and wavefom combinations on and off for each oscillator

The actual pitch of the oscillators doesn't matter, but Osc B shouldn't be in LO FREQ setting

We would expect some "wobbling" once a waveform is switched on. And we would expect a slight change of filter frequency from start of self oscillation till full resonance. Please do not alter the volume during any of these settings (that would defy the purpose, hehehe).

I hope this isn't too much hassle & thank you so much for your help,

- Urs

You might do a lot better posting this in the Electronic Music Instruments & Electronic Music Production section of the GearSlutz forum where these things are spoken of with a much higher frequency.

[Uncle E]

I'll upload recordings of both of my Pro One's. They both work great but the one with the early serial number sounds much, much better than the later one.

I'd be happy to send you the early one to model, if you like. Please feel free to PM or email me about it.

If it helps at all, I also have a couple Prophet 600's with the Gligli firmware.

[Urs]

Hi guys,

Yes, we're still looking for input, but I think we got the answers we were looking for by this request (gain and DC offsets of VCO outputs, harmonic distortion of filter resonance).

I'm contemplating to run another request some time soon to look at other aspects, such as envelope times and shapes.

However, we have plenty of Curtis chips around ourselves that we can swap inside our Pro One.

I'll make up my mind shortly... too exhausted from Superbooth today...

- U

[bsterz]

I'm excited to see this level of care and attention placed on the Pro One, but also glad to have caught the openness with which you are approaching dev side as well. Your blog posts are helping connect a few things that have remained confused for me - as applications in DSP to emulation in this realm has often been held much like a secret art.

[Urs]

as applications in DSP to emulation in this realm has often been held much like a secret art.

Well, you'll also see that matters of DSP are usually talked about in a secret language. It's like the protectors of the realm are talking to themselves, mainly, as if looking to be heard but not understood.

[bafonso]

as applications in DSP to emulation in this realm has often been held much like a secret art.

Well, you'll also see that matters of DSP are usually talked about in a secret language. It's like the protectors of the realm are talking to themselves, mainly, as if looking to be heard but not understood.

The classic art of obfuscation