[sdiy] MN3207 and MN3102 Reissues

[Scott Stites]

Thank you, Mike.  That explanation clears it up quite a bit.

What threw me off was that it looked like switch 1 wasn't doing anything.

For a long while I've been wanting to build an ensemble chorus.  Until you
brought up what this is doing, it hadn't occurred to me that one could get
rid of obvious movement with two BBD's and anti-phase modulation.  Guess
I'll have to study JH's writings about the Dimension D a bit more now!

I've got a couple of NE570's, but many more SA571's.  I know that the 570 is
considered a superior device to the 571, but I may try both out when the
time comes to pull out the BBD's again.  I've got some 572's that would take
some reworking to fit into the circuit (no internal op amp, etc.).  I've got
a nice article in Polyphony about using those.

BTW, OnSemi's app sheet on the SA570/571 shows a method of using the 570/571
with an external (better) op amp and emphasis/de-emphasis for improved
operation (to eliminate breathing and pumping, etc.).  I don't recall seeing
that in the Philip's docs, though that doesn't mean it wasn't there =0).
Perhaps that might make the 571 perform acceptably.

Cheers,
Scott


----- Original Message -----
From: <mirwin at qouest.net>
To: "Scott Stites" <scottnoanh at peoplepc.com>
Cc: <synth-diy at dropmix.xs4all.nl>
Sent: Saturday, October 30, 2004 12:10 PM
Subject: Re: [sdiy] MN3207 and MN3102 Reissues


> Scott (and list),
> The pushbuttons  put in different resistor values for the LFO rate and
> Depth - you could use two pots instead. This is the effect "that you
> don't notice until it's turned off". What is most interesting is
> that the LFO rate does not correspond to the "beat rate", the LFO
> rate is much slower since what it is really controlling is the
> amount of detuning. What they don't mention is that some filtering is
> also applied in "bypass" mode.
> Regards, Mike