670 with solid-state side-chain?

[moamps]

Don't give up so easily. 
There is also  Paravicini's EAR 660 "hybrid" compressor,  IIRC I saw somewhere online the handwriting schematic of it.
Nice studio, BTW. May I ask what type of compressor is Black Bottle?

 

[scott2000]

I saw somewhere online the handwriting schematic of it.

https://groupdiy.com/index.php?topic=67062.0

 

[vinyvamos]

There is also  Paravicini's EAR 660 "hybrid" compressor,  IIRC I saw somewhere online the handwriting schematic of it.
Nice studio, BTW. May I ask what type of compressor is Black Bottle?

Oh thanks! We just opened this June after five years of building it . The Black Bottle is basically a Federal AM864 with all the usual controls added. Sounds great!

Thanks for the tip-off on the EAR 660 guys! I found the hand-drawn schematics and it is an interesting beast. PCC189 and other design choices tell me it was maybe designed based around what was at hand, nice!

I am going to start building up my unit and leave enough space for the original tube sidechain if I want to try it later, but will start off with transistor power amps for that, and also sixteen 6BA6 rather than dropping $1k on an octet of 6386. These will be mounted on a sub-plate so I can always exchange them out for a plate of 6386 if that opportunity arises

 

[alexc]

And then some!

Good going with it  ;D

 

[gyraf]

PCC189 and other design choices tell me it was maybe designed based around what was at hand

..aah, but you shouldn't underestimate the qualities of the PCC189 (7ES8) type of remote-cutoff triode.. I've tried many-many types over the years, and very few come in as good and consistent as that one..

/Jakob E.

 

[vinyvamos]

..aah, but you shouldn't underestimate the qualities of the PCC189 (7ES8) type of remote-cutoff triode.. I've tried many-many types over the years, and very few come in as good and consistent as that one..

OK that is good to know Jakob! It makes me want to go and properly catalogue my boxes of Pxx tubes now . Any pointers as to what he is doing with the PCC88 tubes? Are they increasing the current drive of the stage/lowering the impedance?

 

[bockaudio]

The 666 is nearly unrelated to the 660 or 670, no variable tubes.
I did a SS sidechain 660 for a client, used a UTC A-39 as sidechain input. Was able to develop -120vdc CV, audio chain identical to 660. Wish I had built one for my self. It didn't sound like a "tube 1176" (like the EAR 660, which always was SS sidechain, but a little less "hairy" than any real 660/670 I've heard. The difference in the EAR is more about the xfmrs and cascode than SS sidechain.