linear portamento... the schematic

harrybissell at harrybissell at
Tue Nov 30 17:45:56 CET 1999

Here's the schematic... I've used it for years. Use the 1458 op amp or 741's etc... the TL082 might be too fast and might have the funny latch-up problems. People like to "upgrade" the 741 series... but sometimes they are just right for the job at hand...

:^) Harry

(the new PAiA has expo oscillators or so I am told...)

 ---- On Nov 30 "Mark Cornell" <cornellm.student at> wrote: 
> > I'll forward you a schematic for a "linear" portamento... sorry there is
> > no PCB for it. Its easy enough to wire by hand.
> Ahhh fantastic. That's great thanks. I'm looking forward to getting it!
> > OTOH: the PAiA synths have a "linear" oscillator response... the mini
> > had an "expo" oscillator response.
> > 
> > So the PAiA:   Linear Oscillator + Linear Portamento  <or>
> >                        Linear Oscillator + Exponential Portamento
> > 
> > won't be quite like the
> > Minimoog:       Exponential Oscillator + Linear Portamento
> > 
> > IMHO I like the linear portamento the best anyway... If you want a
> > minimoog sound the PAiA might not quite get it.
> > 
> > I'll post the portamento monday... its a work and I don't want to draw
> > it over again...
> Okay fine. Thanks loads. I'll have to look into all that linear expo
> stuff! But anything that can get me a step closer to a minimoog is
> great.
> > Another easy way to get "portamento" is to put the KBD CV through a
> > hipass R-C filter (cap in series, resistor to ground) and then invert
> > the output and sum it with the KBD CV at the oscillator input. This is a
> > simple and nearly passive way to get glide... I did this on a PAiA 2720
> > before I "discovered" the glide circuit I'm posting (monday)
> Wow. Thanks, I'll try that when I have some actual stuff to do it on!
> Cheers.
> Mark.

-------------- next part --------------
A non-text attachment was scrubbed...
Name: Lin_port.gif
Type: image/gif
Size: 4990 bytes
Desc: text, base64 encoded
URL: <>

More information about the Synth-diy mailing list