Analog Sequencer Poll

[Magnus Danielson]

> blerkum shminkum gstopp, waltz Re: Analog Sequencer Poll larmy teapot coffee
> table hatstand waltz...
> >     I think the Roland System 700 had the capability of setting note
> >     length per step with a rotary switch. The Emu modular sequencer had
> >     the pot panel split off from the step counter, so you could patch up
> >     the binary address lines in strange ways to make the pot steps jump
> >     all over the place.
> 
> This sequencer stuff was just WAITING to be brought up! I'm real interested
> in this area...
> 
> I have in front of me here an ARP Sequencer manual. On the ARP sequencers,
> they have this funky random mode, where it picks out which notes to play at
> random... how would ya implement this ? (without using a CPU!!!). I had the
> idea of using a high speed oscillator, and selecting voltages off it
> periodically... would this work ?

One simple method of generating pseudo-random numbers is by using a shift
register and a handfull of XOR gates. They can cheaply be created with quite
long length and very long sequence before repetion occur. I don't know if this
is the method used in the ARP Sequencer, but it could very well be. A few
resistors and a op-amp buffer and hey, you got random notes...

(I wouln't mind a copy of that manual.... but that is a diffrent issue :)

Cheers,
Magnus