Joe Meek 'Cooker' Unit. Harmonics generator

[barclaycon]

This subject has probably been discussed here before, but it's about the harmonics generator that Joe Meek used to use to fatten up sounds.
I believe it was an RCA Orthophonic pre-amp - a combined mixer and tone control unit that could be easily overloaded to produce lots of 'musical' distortion.
In his recent book,  Adrian Kerridge described this as one of Joe's main units to fatten up sounds. He used to call it his 'cooker'.
Try as I might, I haven't been able to find the circuit for this.
I notice that Phadrus Audio make a unit featuring a 'cooker' setting and mention on their website that it's based on a Wireless World circuit (they even show a little veroboard with a transistor layout).  I haven't been able to find this article either.
Anyway, this would make a great project. Anyone have any info or schematics ?

 

[emrr]

I’m aware of passive RCA orthophonic filters but not an all in one amplified unit.  Perhaps there was a UK specific model. Could be a consumer hifi device. 

 

[cyrano]

According to the internets, it could be a RCA Orthophonic Preamp LMI 32215.

At least, that's what people on ebay think about it... 

https://www.radiomuseum.org/r/rca_photo_high_fidelity_pre_amplif.html

Schematic:

http://www.novacon.com.br/audioercbrib.htm

Some more pics:

http://imglogy.com/tag/joemeekcooker

 

[DaveP]

I have attached the schematic but I can't imagine it will be much use.

What you need is a tube/valve set up to run on the curved part of the dynamic chart, not the straight part.  A combined triode pentode tube like an ECF80 is good for this, you can set the working point of the triode for 2nd Harmonics then the pentode for 3rd and switch between the two.

DaveP

 

[barclaycon]

Many thanks for the info. Much appreciated.

Anyone have the original article from Wireless World ? (Or info on the breadboard thing).

 

[scott2000]

Maybe post a pic of the breadboard here so it can be dated somewhat? Components maybe??

Is the wireless world build sometime after the Joe Meek thing? Based on the Joe Meek thing or something???? The Joe Meek date is around 1960....

Maybe to narrow down what year in August Wireless World to look for .....??

 

[emrr]

Ah, OK, British consumer unit. 

 

[barclaycon]

The Phadrus Phusion website mentions the unit thus:
'The Cooker setting uses silicon transistors and comes from a circuit design
first published in Wireless World magazine as a hobbyist, general-purpose
hi-fi project intended to amplify mic or record pickup signals!
It was christened ‘the Cooker’ by Joe Meek, who apparently used it
extensively for its interesting distortion characteristics'.

I think the article may have been titled 'Orthophonic preamp'