Re: [wiardgroup] Re: Key input on Boogie Filter
2005-12-04 by Bryan E Cornell
Hmm. Would this be true if I had the lfo going to the regular cv input and the keyboard cv feeding the "key" input. Bryan >>> grichter@asapnet.net 12/04/05 12:40 AM >>> That should have read bi-polar control voltage. A the negative half of a bi-polar LFO is at -5 volt which will move the filter down 5 octaves. The 1 or 2 octave keyboard control voltage will not be able to compensate. --- In wiardgroup@yahoogroups.com, "Bryan E Cornell" <bcor@l...> wrote: > > Actually I disassembled the patch and now that I think about it, I may have had an lfo going into the control in. I'll experiment and report back if there is a problem. > > Bryan > > Bryan Cornell > Reference Librarian > Recorded Sound Reference Center > Motion Picture, Broadcasting and Recorded Sound Division > Library of Congress, Washington, DC 20540-4698 > Phone: (202) 707-7833 > Fax: (202) 707-8464 > email: bcor@l... > Usual disclaimers apply. > >>> grichter@a... 12/03/05 5:17 PM >>> > Not sure what is up with that. > > The basic idea is simple. If you use an evelope to sweep a filter, > as the oscillator pitch changes, the extent of envelope sweep remains constant. > So high notes have fewer harmonics than low notes. > By adding the keyboard voltage, you move the filter with the oscillator, > and produce roughly the same amount of harmonics for each note across the keyboard. > > The Mini-Moog has switches for this. Patching keyboard CV to "Key In" is the same as > having both switches down on a Mini-Moog. > > Possible problems are a bi-polar keyboard voltage (+/-) or envelope not connected > to filter "Control In". > > --- In wiardgroup@yahoogroups.com, "Bryan E Cornell" <bcor@l...> wrote: > > > > I'm having a bit of a problem (I think) with the key input of my Boogie filter. I assumed > that you are meant to plug a keyboard cv in here so that the filter will follow the keyboard. > Is this correct? When I tried this, all my low notes were very quiet and the high notes were > loud, resonant, and buzzy. When I unplugged the keyboard cv from the key input on the > Boogie Filter the tone and volume were much more even across the range of the keyboard. > My patch was simple: keyboard CV to mult so it could be fed simultaneously to the > oscillator and the filter. The rest of the patch was the gate out of the keyboard to an EG > and to the VCA into which I had plugged the output of the filter. > > > > I feel like I'm missing something fundamental. > > > > Bryan > > > > Bryan Cornell > > Reference Librarian > > Recorded Sound Reference Center > > Motion Picture, Broadcasting and Recorded Sound Division > > Library of Congress, Washington, DC 20540-4698 > > Phone: (202) 707-7833 > > Fax: (202) 707-8464 > > email: bcor@l... > > Usual disclaimers apply. > > > > > > > > > > > > Yahoo! Groups Links > Yahoo! Groups Links