New Sequencer Schematics Posted

[JDMcEachin]

At 03:47 PM 12/20/96 -0800, Sean Costello wrote:

>I just posted the Moog 960 Sequencer Schematics on my fabulously ugly and
>spartan web page, located at http://www.seanet.com/~costello.  The talk
>about sequencer design made me think that having these schematics available
>might help you designing folks out there, to come up with super features for
>a simply fabulous sequencer board.  
>
>I'll be trying to scan other sequencer schematics in soon, including the
>simply super ARP Sequencer, as well as other fabulous super things.  This
>will be done soon, as I have to go to Kinko's today to complete some long
>neglected photocopying for a select few of you (that have been waiting far
>too long), super fabulous.

I've spent quite a bit of time perusing sequencer schematics (for a possible
commercial product).  Of the SuperSeque, Arp, EML, Serge, System100m, and
System700, I'd recommend using the SuperSeque as a basis for design, with
features adapted from the others.  As far as the digital front end goes, a
little logic will make the SuperSeque do anything the others will do.  The
analogue end is also adaptable and easily modified.  Remember that a
sequencer is a mostly digital device, and there's no "magic" about using
different chips as there is with analogue circuits.  Focus on what features
are useful, and implement them w/ readily available 4000 series CMOS.  Avoid
anything weird, esoteric, and hard-to-get.

I'd say the two features that you probably want to look elsewhere for (or,
dare I say, roll your own) are the clocking VCO and the quantizer.  The
ADC->DAC quantizer is probably the best way to go.

Features I'd like to see - the 3 gate busses from the Arp, a 16 position
"end" switch w/ a pulse out, and a 16 position "cascade" switch w/ a pulse
out, which outputs a pulse when the selected step is reached  (beats
drilling 16 holes for individual step outs, allows you to keep all the patch
cables on one side, and gives you 98% of the usefulness of having individual
outs).

JDM