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Subject: Re: [motm] bipolar output for MOTM-320 saw?

From: Mark <yahoogroups@...>
Date: 2007-06-22

On 6/20/07, Scott Juskiw put forth:
>The saw output on my 320s are all 10 Vpp (when outputting a saw or
>ramp wave). When the SHAPE control is in the 12 o'clock position it
>outputs a triangle wave that is 0 to +5V.

My bad. Upon further inspection, both of mine do the same thing. So
I changed my LED indicator to saw to remind me of that fact. I told
you I could be missing something :)

While I'm typing about the 320, how much of difference in frequency
range have you noticed between 320's?? For example, one of mine,
without any CV, has a top rate of 200 Hz, the other 30 Hz. Is this
due to parts tolerances?? I can't measure their lowest rates with
the frequency counter I have, but if anyone is that curious I could
try using a stopwatch.

On 6/20/07, Richard Brewster put forth:
>It's a feature, not a bug. To get a full sawtooth from the SAW output,
>the SHAPE pot has to be at 0 or 10. Either of these positions results
>in a 10V p-p signal. At 5 on the SHAPE dial you get a 0 to +5V triangle
>from the SAW out. That is useful. No other MOTM LFO produces a 0 to
>+5V triangle wave. In between on the SHAPE pot gives you in-between shapes.

Apparently, it also gives you in-between amplitude and offset.

>I have found that I use the SINE, TRI, and PULSE outputs of LFO's much
>more than the SAW outputs, anyway.

I rarely ever use pulse, except as an occasional clock, and the fixed
triangle is pretty much the same as any other triangle, but the
variable sine shape is awesome!! I built a couple of 10Vpp to 0-5V
converters so I could use the 320 outputs with pedal inputs.

>I suggest that if you want a constant 10V p-p SAW, you can use a
>MOTM-300 or 310 as an LFO.

Well, unless I'm missing something again, the 320 does produce a
constant 10Vpp saw.

On 6/21/07, Andre Majorel put forth:
>
>Don't know but if you can't, the Oakley Little LFO has a single
>sawtooth/triangle output that has, I believe, a constant output
>amplitude regardless of the shape. It's not voltage-controlled,
>though.

I was surprised to hear that Oakley was back in business. Imho, the
issue with third party PCB's is the difficulty in getting panels and
mounting brackets, and the issue with Synthesis Technology diy is
the cost of the parts -- where the just pcb, panel, bracket and
billet parts, not including the knobs, jacks, and all the more common
parts, can cost more than the entire kit did.