minshall schematics

[9pins]

I'm looking for a very rare thing.

This guy started selling home built organs to undertakers in the early forties.
and I guess sold out to Estey in the fifties, his rig was based on a simple tube
frequency divider, I have one reference to the divider circuit, but no good
schematic as to how it was implemented in a practical sense. Just asking around,
I know TAG is not focused on that end of musical electronics but .....
I figured I'd poke around on the off hand chance someone might have come
across a schematic.

[LeftyStrat]

Check out this restoration project for a Hammond Novachord:

http://www.discretesynthesizers.com/nova/intro.htm

You may want to contact the restorer, he may have some info.

[9pins]

jeez... now thats a amp build, holy moly

[9pins]

http://www.novachord.com/schematics.html

thats one complex beastie, theres 12 base oscillators, that are grouped with
a LFO for vibrato, their signal goes down a chain of freq dividers for each
octave of the key board, I can see how any simplification or miniaturization
would be very competitive, so used to PCB and it advantages.

[Structo]

Holy crap that thing is complex.

What an undertaking!

146 tubes in the generator alone!!!!

Before:
[img:576:461]http://www.discretesynthesizers.com/nov ... damage.jpg[/img]

After:
[img:504:310]http://www.discretesynthesizers.com/nov ... gendur.jpg[/img]


The first tones it made after restoration.

[Cliff Schecht]

That's got some great character!

[MCK]

Wow. Thats a pull tube heaven eh?

[Cliff Schecht]

Wow. Thats a pull tube heaven eh?

The power section has 2A3's and there might be a few other interesting types in there, but I bet 95% of the tubes in that thing are useless to us. It's not like it's filled with Bugle Boy AX7's in the oscillator (wouldn't that be a trip!).

[9pins]

The Novachord PS is all regulated, you dont see that much. Minshalls claim to fame was that he came up with a frequency divider based 1/2 a 6sl7/12ax7 which drastically cut the cost of an electronic organ at the time, they got bought out by Estey still on the hunt for a schematic, there used to be a factory in Brattleboro Vermont, had no idea and I've been thru brattleboro several times, I've found a sales flier and a magazine spot but no scheme.

You got to love "Tone Arama" as a pitch.

I remember seeing consoles over at friends houses when I was a kid, dont touch that or my mom will freak out, another thing you see too much anymore.

[RevD]

And you thought you hated to do the heater wiring on YOUR amp... heh... Kidding aside, it sounds warm and beautiful (nova2.mp3), just really goose pimple sounds.. Thanks for sharing!


Regards,

Don

[Gibsonman63]

Thanks for posting the Nova Chord links. I don't feel so crazy about restoring a few guitar amps now.

[RevD]

Here's a little background I found while looking for 'Tone-arama' speaker system... (I suspect but didn't have time to research it before I wrote this, that it was yet another attempt to do something similar to that which Leslie had done). There was a ton of different schemes all trying to give the dopler effect to Organs in an attempt at getting a pipe organ sound. Anyway:

http://blog.modernmechanix.com/2006/06/ ... c-maestro/

Regards,

Don

Ps: Essentially Tone-arama was just a pair of speakers, I'm assuming using two they got a psuedo stereo separation after it bounced off a few walls making it sound fuller..

[cbass]

Wow! what cool sounds!