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Completing the model

Open jpcima opened this issue 6 years ago • 3 comments

I've quickly checked the model against Solina schematics, identified major lacking elements. (answering also @farvardin on completeness of implementation)

In the original, the 4' and 8' sections are known as violin and viola respectively.

  1. missing: brass section (trumpet/horn) It's needed to identify what does the formant circuit folllowing the oscillator. It has a set of switches which seem to affect a characteristic of a filter. Capture du 2019-07-15 19-18-01

  2. missing: bass section It's cello and contrabass, and it has a more complex circuitry, of which I'm not fully sure how it fits in the model. It's made from various parts: low-tone selection, clipper, trigger suppression, bass sustain, and low-pass filter

Capture du 2019-07-15 19-26-22 Capture du 2019-07-15 19-27-10

jpcima avatar Jul 15 '19 17:07 jpcima

Some ltspice sims of formant filters, having switch in horn or trumpet position.

formant.zip

Horn Trumpet

Peak approximately at 1.445 kHz (horn), and 4.445 kHz (trumpet)

jpcima avatar Jul 16 '19 15:07 jpcima

Attempt at the formant filter in the brass branch

jpcima avatar Aug 08 '19 20:08 jpcima

Note to self:

The service manual of ARP Omni has a description of circuits in plain english ! Including an explanation of bass parts.

http://www.synthfool.com/docs/Arp/ArpOmni/ARP_Omni_2480_service_manual.pdf

jpcima avatar Dec 31 '19 21:12 jpcima