blueshift dim-c clone

Done done done. I made the holes for the switches a bit too big, might need some bigger washers.

Aion Blueshift boxed

Really boring round the back, it’s pretty tight.

Aion Blueshift inside back

Inside! it’s packed out. If I’d’ve designed this board it would’ve ended up about two feet square.

Aion Blueshift inside

If you’re going to build it, use the specified capacitors – the ones I used were too tall, although I’ve just about got away with it.

I’ve recorded some basic demos just to get an idea of what the Blueshift does to a source.

Here’s the Blueshift on DC power (hence the hum, unfortunately) having a simple polyphonic JX3P sequence shoved through it while I flip the switches at random. See if you can tell when I turn the Blueshift on:

And here’s another one on battery power, first section no effect:

It seems like it’s very shy of higher levels – I had to notch the JX3P down to its “M” output level to avoid distortion, and like I say, it seems to hum with the DC adaptors I’ve got, although I don’t necessarily trust any of them.

But I really like the way it sounds, and it can do exactly what I wanted, which is to widen a mono source without sounding too obviously swooshy and chorused.

The pedal format isn’t really ideal in my studio but I just wanted to get it done. I’ll pretend now that I could make it into a half-rack or something, but that won’t ever happen.

It’s so nice I’m tempted to have a look at making a more rack/studio-ish Dimension-D-type thing, maybe J├╝rgen Haible’s Subtle Chorus or something. But this will do for now.

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LED indicator noise in System 700

I’ve never been able to get the LED indicators to work well in any of the System 700 circuits I’d made. Even with no input, the green light would stay on and horrific screechy noise would get injected into the output.

Vowing to finally get it sorted out I connected up my 703E VCF clone, got the expected horrible noise and stuck my oscilloscope on the +14.4V LED power line. It showed that the power line was oscillating at about 32MHz, at an amplitude of about 200mV.

Then I tried some stuff like bunging different capacitors on the LED power line and different power supplies, but nothing did the trick.

Some of the schematics suggest that CD4001AE is the right version of the IC to use, although confusingly, not all of them. Also all the pictures of the boards I’d seen have AE or UBE versions of the 4001 in place. Found some old RCA AE variant chips on eBay and gave them a go:

CD4001AE in the 703E filter

DAMMIT IT WORKS.

I wasn’t keen on relying on 35+ year old CMOS chips, so I ordered a few 4001UBE, and they work too.

Mystery solved, put the kettle on.

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100M 140 envelope panel

100M 140 envelope clone

My clone-ish 100M panels were from Schaeffer using their UV print process. Not as good as screen printing but still really good.

Shame about the “env 1 out” on the second envelope out, could’ve been worse though. Would have liked to have it in grey but couldn’t see that as an option, so strangely it looks a bit 700-ish. And pretty much as big, which I realised later, wasn’t really the point of the 100M.

Oh well – it’s built now, and it’s bloody massive.

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