MOTM

>From: Steve <eboyz@...>
>
>I think the MOAS idea is wonderful. However, a small 'utility' sequencer

could

>also be very useful, and this could be realized much sooner than the MOAS.
>Something like 8 steps with a couple of gate buses, externally clocked,

ability

>to be daisy chained so 2 could give 16 steps, or 2 rows of 8 steps. This is

a

>simple design, but it would be nice if it was in the same style as the rest

of

>the MOTM system. Kind of a 1/2 arp sequencer in a 3U panel thing, 2 columns

of

>4 knobs each and then a column of switches 2 wide. What do you guys think?

Hi Steve,

My suggestion is that you get one of the MOTM breadboards and build a 8 X 2
row sequencer. I've had one of these boards for awhile now, but I can't think
of anything complex enough to justify using it (they are very good, and can
hold a number of components). A sequencer would be perfect for this board.

I would build it on a 3U MOTM panel using smaller knobs on a smaller hole
pattern than the standard MOTM one. It would have 16 pots in a 4 X 4 pattern,
with room for 18 jacks (three rows of 6) below. You could have: clock in, 2
sequencer outputs, 8 pulse outs (1 for each stage), reset, hold, up/down, with
4 leftover for good luck!

I would suggest not using a 4017 decade counter, but rather using a CD 4516 as
the "driver" connected to a 4051 for stage select. With the 4516 you'll be
able to have up/down which the 4017 won't do. I have a schematic of this
around here, and would be surprised if one wasn't on the web.

John B.

How about a small sequencer design contest? On paper, a 2U or 3U wide panel.

Design it out, scan it or fax it to me (817-498-3782) and I'll eye-ball it.

In fact, there is no 'winner'. What I'll do is summerize each one.

Here is a good MOTM Module Sequencer Calculator (not what I use, but it will
give you an idea)

Baseline cost = $65 (pcb, res/caps/ICs, wires, brackets, overhead, profit,
blah blah blah)
Panel adder 1U = $12, 2U = $22, 3U = $36
Each pot/knob = $10
Each Switch = $5
Each jack = $4
Each LED = $3

Difficulty factor

Easy = 1X
Not that hard = 1.2X
Pretty hard = 1.6X
A Mother! = 2X

So a 3U wide, 8 pot/8 LED with a manual STEP button (counts as a switch),
int CLK pot,and
EXT CLK IN, 1 MASTER CV out, 8 individaul stage jacks (gate/trig cv
whatever) would be.....

65 + 36 + 9x10 + 5 + 8x3 + 10x5 x 1.2 = $324 kit price (roughly!)

In reality, there are games to play with the pot quality (shudder!), but the
point is that sequencers
can get expensive quickly in the MOTM way of thinking. Note that it really
does NOT matter
what the exact nature of the electronics is: this is the rule in every
module so far (the VCO is
another story!). The cost everyone pays for is NOT the electronics: it's the
quality of the pots, jacks,
and panels.

Have fun!

Paul S.

Well folks,

I've sent my sequencer designs to Paul. Where's yours? I cheated, however.
There's no way to get a bunch of knobs on a 3U panel and all the jacks
needed to do anything really interesting. I submitted 3 modules, based on
ideas stolen from the Emu modular sequencer, but in a MOTM format:

1. A 2U 4 stage address generator, with chaining capability, set inputs and
pushbuttons for each position, hold, rnd, and down. Don't need a reset
because of the set inputs.

2. A 4U 4x4 matrix voltage source.

3. A 2U gated 4 input mixer, that can be used with the address generator for
a simple 4x1 sequence, or to control the matrix voltage source output to get
8x2 or 16x1 configurations.

Later!

Dave Bradley
Principal Software Engineer
Engineering Animation, Inc.
daveb@...

> -----Original Message-----
> From: Paul Schreiber [mailto:synth1@...]
> Sent: Saturday, February 06, 1999 5:21 PM
> To: motm@onelist.com
> Subject: [motm] Re: Why not breadboard a small MOTM sequencer?
>
>
> From: "Paul Schreiber" <synth1@...>
>
> How about a small sequencer design contest? On paper, a 2U or 3U
> wide panel.

In a message dated 2/9/99 5:08:52 PM, "Dave Bradley" <daveb@...> wrote:

>1. A 2U 4 stage address generator, with chaining capability, set inputs and
>pushbuttons for each position, hold, rnd, and down. Don't need a reset
>because of the set inputs.
>2. A 4U 4x4 matrix voltage source.
>3. A 2U gated 4 input mixer, that can be used with the address generator for
>a simple 4x1 sequence, or to control the matrix voltage source output to get
>8x2 or 16x1 configurations.

Brilliant Dave!

I'd been drifting back towards this (modular) idea since you got me thinking
back to the EMu. I'm wondering what you mean by the 4X4 voltage source matrix?

John B.

John sez:

> Brilliant Dave!
>
> I'd been drifting back towards this (modular) idea since you got
> me thinking
> back to the EMu. I'm wondering what you mean by the 4X4 voltage
> source matrix?
>

I meant merely the classic rows of pots - 4 rows of 4. In this scheme, the
address generator module just generates the states, and the pots belong to a
separate module. The address generator has binary output jacks, which is a
more compact way of describing the current state than the individual gate
outputs. A 4 stage generator would need 2 binary state jacks, an 8 stage
would need 3. The voltage source matrix (pots) has matching binary input
jacks to stay in sync. Why separate these functions, you ask? Panel real
estate is one issue, another is flexibility. I may want to clock 4 of these
address generators in parallel, and use a 5th to be clocked from various
gate outputs, and in turn feed its gates back into the others. Also, the 4x4
matrix could be left out entirely if you just needed a simple 4x1 sequence,
as mentioned below. On the original Emu scheme, the address generator was 8
positions, and the pot matrix was 8x4. That took up 9" and 12" respectively
horizontally. If I was building this for myself in a MOTM context, I'd
probably build both 4 and 8 position versions. The sequencer is just going
to take up more real estate than other system components.

> -----Original Message-----
> From: JWBarlow@... [mailto:JWBarlow@...]
> Sent: Tuesday, February 09, 1999 8:00 PM
> To: motm@onelist.com
> Subject: [motm] Re: Why not breadboard a small MOTM sequencer?
>
>
> From: JWBarlow@...
>
>
> In a message dated 2/9/99 5:08:52 PM, "Dave Bradley"
> <daveb@...> wrote:
>
> >1. A 2U 4 stage address generator, with chaining capability, set
> inputs and
> >pushbuttons for each position, hold, rnd, and down. Don't need a reset
> >because of the set inputs.
> >2. A 4U 4x4 matrix voltage source.
> >3. A 2U gated 4 input mixer, that can be used with the address
> generator for
> >a simple 4x1 sequence, or to control the matrix voltage source
> output to get
> >8x2 or 16x1 configurations.
>

Dave Bradley
Principal Software Engineer
Engineering Animation, Inc.
daveb@...