Search found 26 matches

by stefanv
Tue Apr 26, 2016 8:29 am
Forum: PAiA Jabber
Topic: 4700 Modular-Kbd question
Replies: 2
Views: 15787

Re: 4700 Modular-Kbd question

In theory, yes. The Stringz'n'Thingz has two contacts per key, one used to key the notes, the other to activate the noise gate. The latter could be replaced by adding diodes to the keying contacts, and deriving a gating signal from that, thus freeing up one set of contacts. Those contacts could then...
by stefanv
Mon Jan 11, 2016 8:55 pm
Forum: PAiA Jabber
Topic: Chord EGG 2015
Replies: 23
Views: 76563

Re: Chord EGG 2015

I've now finished the alarm clock for which the Chord EGG 2015 was meant to be a music source:

Building a Musical Sunrise Quartz Alarm Clock

Image
by stefanv
Wed Dec 23, 2015 9:04 pm
Forum: PAiA Jabber
Topic: Chord EGG 2015
Replies: 23
Views: 76563

Re: Chord EGG 2015

Thanks everyone for your input and encouragement. I've written an article describing this new Chord EGG design:

Chord EGG 2015: Remaking a PAiA Classic
by stefanv
Sun Nov 01, 2015 9:05 pm
Forum: PAiA Jabber
Topic: Chord EGG 2015
Replies: 23
Views: 76563

Re: Chord EGG 2015

Here's a photo of the completed board (click to see full size):

Image
by stefanv
Thu Oct 29, 2015 10:57 am
Forum: PAiA Jabber
Topic: Chord EGG 2015
Replies: 23
Views: 76563

Re: Chord EGG 2015

No, it's pretty much a direct remake of the original functionality, without using any hard-to-get parts.

However, it ought to be fairly easy to build a subset of it (for example, the note randomizer), for use as a pseudo-random control voltage source.
by stefanv
Wed Oct 28, 2015 8:50 pm
Forum: PAiA Jabber
Topic: Chord EGG 2015
Replies: 23
Views: 76563

Re: Chord Egg 2015

First recording!

http://www.stefanv.com/media/2015/10/ChordEgg2015.mp3

Photos of the rest of the construction to follow when I get a chance.
by stefanv
Wed Oct 28, 2015 2:40 pm
Forum: PAiA Jabber
Topic: Chord EGG 2015
Replies: 23
Views: 76563

Re: Chord Egg 2015

I'm not too worried about absolute stability. They are bound to drift with temperature. However, they should all drift about the same amount, so the relative tuning between the notes should be quite stable.

My redesign uses a single 12V supply, just like the original.
by stefanv
Sun Oct 25, 2015 6:19 pm
Forum: PAiA Jabber
Topic: Chord EGG 2015
Replies: 23
Views: 76563

Re: Chord Egg 2015

I just finished wiring and testing the part of the Chord EGG 2015 that I'm most proud of, the chord randomizer. First, here is the original PAiA chord randomizer circuit: http://www.stefanv.com/media/2015/10/PAiAChordRandomizer-276x211.png Two low frequency oscillators at different rates generate a ...
by stefanv
Sat Oct 24, 2015 9:03 pm
Forum: PAiA Jabber
Topic: Chord EGG 2015
Replies: 23
Views: 76563

Re: Chord Egg 2015

The original Chord EGG only alternates between four chords in one key (C-E-G, F-A-C, D-G-B, and E-G-C'), so only 8 notes are needed (C, D, E, F, G, A, B, and C'). Unlike the original Chord EGG, which used a top-octave synthesizer chip generating an equally tempered scale (of which only 8 of the 13 n...
by stefanv
Sat Oct 24, 2015 4:06 pm
Forum: PAiA Jabber
Topic: Chord EGG 2015
Replies: 23
Views: 76563

Chord EGG 2015 - Note Randomizer

I've completed the four low frequency oscillators that control the note randomizer. Once again, a TL074 quad op-amp is used:

Image

Next up are the chord randomizer oscillators, and the 2-bit to 4-line decoder.