THAT chip compressors

[Strategy]

There are some DIY compressor projects geared towards the modular synth forums like muffwiggler
(like this guy's stuff: http://www.l-1.su/Microcompressor.html)
that are using the THAT series of VCA and compressor chips... I am just finishing up the Modified Q&D Compressor project from this forum which is a monolithic design using SSM2166 and I like the clinical sound of it and extra controls - a nice cointerpoint to the optical compressor designs and squeezers.

are there any circuits floating around here that are using these THAT chips?

Strategy

[armdnrdy]

The Boss CS series compressor/sustainers use UPC1252H2 VCA's

There were other companies besidesThat Corporation (no pun intended) that manufactured VCA ICs.

dbx (remember that name on audio electronics? Precursor to Dolby) UPC, ect.

Even Cool Audio has gotten into the game.

You can still find NOS UPC1252H2 or retrofit a That VCA into the circuit. That Corp's website has a PDF on swapping out older model for newer products.

[garcho]

Their 2180 data sheet application circuit is intriguing - an 8-pin VCA with one resistor!   (...and an opamp)

[Strategy]

It might be redundant to get into a THAT circuit or similar...I am REALLY liking the Modified Q&D Compressor/SSM2166 design...smallbear's SMT-adaptor chip setup is costly but with a low parts count it doesn't end up being very expensive overall.

[garcho]

You probably saw these, but for anyone else...

Mr. Jack Orman's 2166 design

this thread

some Mark Hammer thoughts

[Strategy]

Yes!! I still can't find the thread where I got the documentation PDF for the single-sided layout...It's the Jack Orman project that incorporates basically all of Mark Hammer's mods. Entitled, "Modified Q&D Compressor". I know it came from this forum but can't find it now.

I will repost the PDF later to my website. It's an easy and verified layout

Strategy

[MetalGuy]

THAT chips are of very high professional quality, can be used for various projects and not hard to find. Check out THAT4301 and their design notes which include several compressors:

http://www.thatcorp.com/4301_Analog_Engine_Dynamics_Processor.shtml

http://www.thatcorp.com/Design_Notes.shtml