Sequential Switch and general sequencer confusion....

[Bodega]

Hi all!

I was going to make a project where I'd have an 8-step sequencer and each step would have a simple octave control, the design for which I've already picked out.

That leads me to believe that what I need is something that generates a cv, selects between 8 send/returns and then routes that to one master output. In other words, a fairly standard sequencer (from what I understand a sequencer to be, anyways).

From a look at the Sequential Switch page it appears that it can choose between 8 inputs but not 8 outputs. Am I right in thinking the Switch is not what I need, or is there a way to set it up that would work in my setup?

thanks lots!
Matthew

[Bodega]

Nobody?

I guess it is a bit of a newbieish question....

[blue hell]

[The Bad Producer]

Hi Bodega,

Not sure if this is helpful, but I built a sequencer using the CGS 07 boards.

This has the individual pulse outputs for each step going to a 1 pole 8 way rotary switch, meaning you can send each steps pulse to one of 8 outputs.

If you put a pot wired as a voltage divider before each switch, you could change the voltage going to each switch (only lower though I suppose).

I guess it would be easy to apply each of these 8 outputs to 'thingamajig (octave thing)', and then sum them all together after 'thingamajig (octave thing)'.

Not sure if this is what you had in mind though!

Charlie

[Bodega]

Thanks for the replies, guys.

I'd like to use this circuit to adjust the pitch of each of the 8 steps:

http://electro-music.com/forum/post-251404.html&highlight=#251404

So it would be N>1 (i.e. the switch cycles through the 8 steps, which goes to a single out)

[fluxmonkey]

i believe you make 8 simple voltage dividers: 8 pots, ground all the left lugs, positive voltage to all the right lugs, each wiper going to on of the 8 inputs. so as the sequential switch cycles thru the 8 inputs, it will output whatever voltage it sees from each pot/divider, in sequence.

b

[Bodega]

Right. I just corrected my previous post.

Obviously I'd need 8 of the octave switches and not just one.

So it looks like the SS would indeed work for what I need.

And just for the record - I know controlling a sequencer's output with just octave switches is a little boring, but I'm doing this for an art installation and I want something maximally simple.

[Bodega]

Now that I've got it in front of me, I'm wondering:

1) what are the 4 holes that are just in front of the power connector, by where -0.6v is written? They look like posts for heat sinks, but I'm sure that's not why they're there. There doesn't seem to be anything in the parts list that corresponds with those kind of holes.

2) Are the arrows after the LEDs just to REALLY make sure you know which direction they are going, or do they indicate something else?



3) Finally, just to save me a trip around town: the 10n cap by the power connector - can that be substituted with another value? I don't happen to have any 10n/.01uF caps on hand. I see that it's in the path of the Reset In, but I'm not sure how crucial that value is.

Any thoughts would be much appreciated...
Matthew

[andrewF]

[neandrewthal]

[Bodega]

Oh, no diodes for me - I do like the blinknenlights!

[Bodega]

Hi again, collective EM group mind,

Finally decided I'd better get this thing working property. It cycles fine, and switches direction fine, but I can't seem to get it to reset. So it goes 1-8 or 8-1 but I can't seem to dial up shorter sequences. It seems that P1-8 all put out a voltage in the +5v neighbourhood.

If I connect, say, P4 directly to RST OR RSS, that should reset every cycle on the 4th step, right? Mine doesn't seem to do that.

Incidentally, I've been assuming that the RST is looking for a +5v Gate or Trigger, and the vertical line on the schem above between RSE and +15v means a momentary switch. If either of those aren't the case, it might explain some stuff.

Any help would be greatly appreciated! I've been looking at this thing for months without having the wherewithal to get it working....

Matthew

[andrewF]

[Bodega]

Thanks Andrew!

So in terms of which voltages go where in your build:

RST - 0v, or the +5v of an individual gate output if it's plugged in
RSS - not connected to anything
RSE - always connected to +15v, except when broken by the momentary switch

Is that right?

When I hardwire RSE to 15V, one of the Up/Down switch's positions locks the sequencer in first position until I flip the switch again. That gives me the impression that it should be an Normally-closed type. Unless, of course, something else is wrong in my build....

[andrewF]

[Bodega]

It does!

I'll give it another look tomorrow and see if I can't bridge the gap between it making sense and it making the sounds I want it to make.