From PPilgrim@Teleglobe.CATue Jun 13 10:38:14 1995
Date: 13 JUN 95 07:28:42 EDT
From: PPilgrim@Teleglobe.CA
To: electronica@andrew.cmu.edu
Subject: re: Delta

Forwarded to:      INTERNET [electronica@andrew.cmu.edu]
          cc:      
Comments by:       Philip Pilgrim@PENNANT POINT@OPS
Comments:      


I thought someone else may like this info too.

   -------------------------- [Original Message] -------------------------      
Matt

The Korg delta is a poor replacement for a PPG. It is more of a string 
machine than a synth. I bought mine used in 1984 for $500 but now I would
only pay $100.

The main problem with the Delta is that all polyphonic voices seem to share
one envelope. This results in the loss of decaying notes when new ones are
played. It is like a monophonic in this respect. This effect can be used
creatively but one quickly tires of it. The roland RS-09 string/organ has
this same economy.

The synth section was the weakest point of my synth for 8 years until
I removed the rubber stoppers on the top and tweaked the trimmer pots
underneath. Boy can that filter self oscillate now! It was the whimpiest
filter before hand. Now it sends children running!
I use the synth section only for percussive sounds.

Interfacing is also a weak point. It complies to the non-Roland Hz/V ratio.
Also you have to get schematics to add an external CV in (the gate is there
already. It is called trigger in) A trigger out is also present.

The synth architecture is straight forward:

VC0>VCF>VCA
 |   |
  LF0

The LFO is only Sine
The VCF has Freq, Res, +/- slope knob with env mod amount
The VCO has 4 frequency multipliers so it  has 5 sliders from 32' to 2'
I think that the VCO is only square wave.
A noise slider is also provided
Envelope is ADSR

I would recommend a Yamaha CS-50 or 60. They are heavy but inexpensive.
They also have a ring modulator and true polyphonics. 
I just picked up a Jupiter 4. It is wonderful too and cheap.

I hope this helps. I'm still up for more questions too.

Philip