Project PRO2021 - A Pro-One keyboard synth

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Cablebasher
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Re: Project PRO2021 - A Pro-One keyboard synth

Post by Cablebasher » Mon Sep 14, 2020 3:20 pm

Kevin, thanks for the very detailed info on matching my own resistors.

But in order to get this synth up and running ASAP I have ordered some of those SMD resistors from Farnell.

Thanks Devin.

Cablebasher
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Re: Project PRO2021 - A Pro-One keyboard synth

Post by Cablebasher » Sat Oct 10, 2020 5:52 am

Hey guys.

So I have got to the audio and MIDI wiring.

Nearly there.

Just to confirm:

For the Audio: I need to get both the Black cable and the shield into one of the molex pins? That will be fun...

For the midi:

I just leave the shield hanging (not connected) at the PCB end.

Cheers as always .

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devinw1
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Re: Project PRO2021 - A Pro-One keyboard synth

Post by devinw1 » Sat Oct 10, 2020 12:57 pm

That is correct! On the audio one, It's not hard though, there is a uninsulated wire that runs through the cable that is connected to sheild. You just twist the 2 together. There is plenty of room.

Cablebasher
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Re: Project PRO2021 - A Pro-One keyboard synth

Post by Cablebasher » Mon Oct 26, 2020 2:53 am

Finished!

and everything works first time. Mine was number 9 of the original 14 (I think)

Great synth, amazing build doc, very easy to put together, a serous effort gone into every part of the project.

That mod and Pitch wheel? Yum!

Wonderful work Devin.

If I could describe the synth in 2 words it would be loud and angry.

I’m a little sad it’s finished to be honest.

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devinw1
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Re: Project PRO2021 - A Pro-One keyboard synth

Post by devinw1 » Mon Oct 26, 2020 10:33 am

That's great! I know the feeling, but that's why you've just got to keep a steady stream of projects cued up! :D

Cablebasher
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Re: Project PRO2021 - A Pro-One keyboard synth

Post by Cablebasher » Sun Nov 01, 2020 5:23 pm

So I have most things working and calibrated.

The only thing I can’t do is get the audio in to gate the envelopes.

The gate in jack does it and when set to external mode this also syncs the LFO (should it be doing that?, not mentioned in manual).

When I then plug in an audio signal the audio stops (I mean the sequence or arp is no longer synced to the external gate (as per the manual) but I get no gating from the audio in.

I have tried a guitar and also a synth but neither do it regardless of volume

Have others got the envelope follower to work?

I will get the scope out and poke around U107.

Thanks as always.

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devinw1
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Re: Project PRO2021 - A Pro-One keyboard synth

Post by devinw1 » Mon Nov 02, 2020 11:55 am

First off, it's a little weird the way they (SCI) wired the audio in jack. You need to for sure make sure you use a mono (TS) cable, not a sterero/balanced (TRS).

I honestly haven't played with the audio in a lot, but I believe the way it's set up and what I've read in the Technical Manual, yours is working the way it was intended. The AGATE signal will only be affected by the LFO (which is clocking the sequencer) when there is enough audio to trip the audio comparator, I believe. The amount of audio signal the audio comparator sees depends on where the Audio/Noise mix knob is. So, try adjusting that. I remember when briefly playing with this, that it wanted a fairy "hot" line level signal too.

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