I used to have a printout of the Dyno eq curve and I lost it. I can't find it in the web, I think it might have come from the patent. If anyone knows where to find it, or could post it please help. Thanks.
I made a SPICE model of the dyno preamp, and so can print out a frequency-response curve. Of course, the frequency response changes with pot settings. Also, I have seen a few different dyno schematics, and some of the component values differ between them. Does anyone have a definitive schematic that they know is correct because it was checked by comparing it to an actual original dyno preamp?
I have a picture of the preamp and a schematic of of it. I think this one is an original from 1979.
And pnoboy is right. The layout for these preamps did change over the time Dyno-My-Piano was in business. This is my Pro EQ and Chorus unit from 1982 that I'm having placed in my 1973 stage Fender Rhodes. Notice that it's much more compact than the '79 one.
That is amazing, I thought that these smaller chorus modules were developed by Chuck Monte (not the famous tri-chorus ones) in fact it's just a Boss CE-2 chorus PCB added on.
Thanks for posting.
Quote from: gwike on August 12, 2016, 08:58:49 AM
I have a picture of the preamp and a schematic of of it. I think this one is an original from 1979.
In the schematic you posted, some of the components have 2 different values--one in black, and one in red. Can you verify the value of each of these components with your actual unit? If so, maybe we could say that we have a correct schematic. I suppose it's also possible that dyno preamps from different eras had one or the other of these component values. Some of the differences are small, while others are significant.
Quote from: tjh392 on August 12, 2016, 11:07:59 AM
That is amazing, I thought that these smaller chorus modules were developed by Chuck Monte (not the famous tri-chorus ones) in fact it's just a Boss CE-2 chorus PCB added on.
Thanks for posting.
Chuck Monte did develop a stereo version of the CE-2 chorus known as the Dyno-My Piano 1215 Dual Chorus. Then the dual was later developed into the tri-stereo chorus rack mount module.
The Tri stereo came about in a slightly different way... I have never seen the mod in real life, only read about how they did it, but they used two chorusunits, where they routed 1/3 of the pickups into one unit, the other 2/3 into the other unit and lft the last 1/3 unprocessed, creating a tri stereo effect. This is what supposedly led to the rack unit developed and produced by San Music Corp in Japan.
I made this based on the same schematic. Works fine, but since there is like 20x boost on highs, it's pretty noisy.
https://www.youtube.com/watch?v=Cf-HroHJsQo
You can get pretty similar results with the bbe sonic maximizer. And if you are more into chorus than the suitcase tremolo, CE-1 is the king of choruses for Rhodes, in my opinion.
Cheers,
Janne