[sdiy] Seeking for help, building a bass synthesizer.

[Scott Gravenhorst]

Triangle is also fairly simple and is easier to waveshape into sine using
various techniques.  Most triangle VCOs also have a square output as well.

The B waveform looks like a clever dual level shift and clipping circuit with
sine as input might work.  Say the sine wave is 10 volts peak to peak, if
level shift and clip it at say, +3 and -3 volts, then add the two together, I
think you'll get waveform B.  The +3/-3 volt threshhold could be adjustable.

Note also that no matter what you do, VCOs are not perfect and will not stay
locked in phase across the entire range.  If this is important, you shouldn't
use 3 VCOs, rather one VCO with waveshapers.  On the other hand, 3 VCOs can
make a nice fat output if they are just slightly off tuned.  I do like the
sound of 3 VCOs together.

Several people here have great waveshaping ideas, Ian Fritz
<http://home.earthlink.net/~ijfritz/> comes to mind, though I'm quite sure
there are more.

I'm curious to know why you have interest in waveform B in particular.  What
properties does it have that you desire?


"Fredrik Carlqvist" <ifrc at iar.se> wrote:
>
>What waveform are you trying to create? 
>
>I would suggest square or saw VCOs to start with, you can always add a
>waveshaper later on. Sine VCOs are normally more complex than saw VCOs. 
>
>
>Fredrik C
> 
>
>-----Original Message-----
>From: owner-synth-diy at dropmix.xs4all.nl
>[mailto:owner-synth-diy at dropmix.xs4all.nl] On Behalf Of Rouslan Placella
>Sent: den 1 februari 2005 17:15
>To: synth-diy at dropmix.xs4all.nl
>Subject: [sdiy] Seeking for help, building a bass synthesizer.
>
>Hi everybody,
>my name is Rouslan.
>I'm trying to build a bass synth. And I found out that to generate a
>suitable
>
>wave for this I need 3 VCO. The first one should do a regular sin wave, but
>the other two should do something like the figure B(at twice the frequency).
>
>I still didn't come up with anything...
>Can anybody help me out?
>
>
>
>  _     _     _
> / \   / \   / \         (let's say this is a sin wave)
>A.  \_/   \_/   \_/
>
>
>  _           _
> / \___   ___/ \___   
>B.     \_/         \_/
>
>Thanks to everyone in advance, Rouslan.
>
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>
>
>

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