You can get Vactrols from Mouser I believe, about $5 each......I got these to experiment with. They vary a bit more from part to part than Vactrols, but they work......
Electronic Goldmine - Audio Opto Coupler
im going with the Optocells, ill just buy one or a few different kinds, maybe make one someday, but the Vactrols don't excite too much, i have one here from a SS guitar pedal & i just LOVED how it sounded, so maybe ill try both, but for now, I'm going the LA-2A way, we'll handle changes later and trying to implement other Compression methods ways such as vari-mu + vactrols :")
thanks again tubular.com, another great find, just as the 6ba6 tube find you said would work:]
but yes, I'm keeping it simple, REDD47 -> LA-2A -> Pultec :'P
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An externally hosted image should be here but it was not working when we last tested it.
..I have alll the parts + a few extra add-ons like "Seeing Eye Valve", etc. I know I am literally the ONLY one left on this forum's thread w/ Merlin + TubeLab keeping me afloat... However, I knew coming into this that I would be alone... due to my excessive rambling & off-the-wall ideas I would alienate myself & my ideas would strike fear in the hearts of Men!! (LOL). But I'm here + I followed through😉
The picture quality should be high-enough that you can read the Part #'s on the valves. I'll Draw up a Box-Diagram now I have the main parts pulled & laid before me.
Thanks again guys:")
For sticking it out
& hangin in there w/ Me:]
-ta
Limiter Section: LA1D
Where can i get 3U (or any U for that matter) chassises like this that have the from panel that folds down -- as seen in the LA2A as well --
Ok, back to the build. I want to use this as the tube-compressor: Vari-mu section. here is schematic:
http://gyraf.dk/schematics/CCA_LA1D_Limiter.gif
now i don't need the transformers if i am just connect differ stages like this one & the ones previously mentioned din my past posts -- thnankx
Where can i get 3U (or any U for that matter) chassises like this that have the from panel that folds down -- as seen in the LA2A as well --


Ok, back to the build. I want to use this as the tube-compressor: Vari-mu section. here is schematic:
http://gyraf.dk/schematics/CCA_LA1D_Limiter.gif
now i don't need the transformers if i am just connect differ stages like this one & the ones previously mentioned din my past posts -- thnankx
You need to go to THIS website immediately - it's like diyaudio but it's geared specifically toward recording studio gear, and they'll know exactly what you're talking about. If ANYONE knows about a drop-down front panel for rack-mount studio gear, someone there does.Where can i get 3U (or any U for that matter) chassises like this that have the from panel that folds down -- as seen in the LA2A as well --
Many of the projects are making reproductions of classic compressors and such - go the Dynamic Processor forum and you'll see what I mean:
GroupDIY - We break stuff...and occasionally make stuff.
This reminds me how I only stop in there every year or two. I recall about 15 years ago it was part of a larger recording website. Too many things I wanna do, not enough time in life...
Also, the more you read and understand basic electronics, the better you'll be able to look at a schematic and decide whether you can make "reasonable" substitutions using what you've got. I just added a description of Make: Electronics here, you may find it helpful:
Electronics:Recommended Reading - diyAudio
I thought you were going cut the panels to size yourself, if so, how about getting some flip-down drawer hardware from Home Depot or Loews and DIY it?
Not flip down, but decent rack mount chassis for the price. I have used the top two steel/aluminum units. The 2U box is heavy enough to handle a 50 watt guitar amp with a 5 pound OPT and an Antek toroid for power. Haven't tried the plastic stuff yet. This place has other good surplus parts too. I used to see them at the Florida hamfests.
19" Rack Mount & Acces. | MPJA.COM
19" Rack Mount & Acces. | MPJA.COM
An externally hosted image should be here but it was not working when we last tested it.
Parts -- Done.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
Parts+Psu+Reg48vPhntm 😱
An externally hosted image should be here but it was not working when we last tested it.
Signal-chain->
Utc HA-100x : .
-
Mic Pre - All[emoji14]arts ; .
-
* compressor - some.parts : .
* variable inductor eq - some.parts : .
-
Single-ended Output - All[emoji14]arts ; .
* optional* Push-Pull Output - All[emoji14]arts ; .

. ; So here is the Preamp Chain w/ options of:
. ; Dynamics | Eq | P.P.-output : .
:Signal chain:
. ; HA-100X ->
. ; RQEDD.47 Pre ->
*Option of limiting Compressor*
*Option of Variable Inductor eq*
-> Single-Ended : .
-> Push-Pull *ELL80 : .
An externally hosted image should be here but it was not working when we last tested it.
. ; So here is the Preamp Chain w/ options of:
. ; Dynamics | Eq | P.P.-output : .
:Signal chain:
. ; HA-100X ->
. ; RQEDD.47 Pre ->
*Option of limiting Compressor*
*Option of Variable Inductor eq*
-> Single-Ended : .
-> Push-Pull *ELL80 : .
Have you hit the "on" switch to any of this, yet?
So what you need is to learn the fundimentals of amplifier design. Then you can design something with your parts and actually commence with a build.
There are some good books to start with. "Valve Amplifiers" by Morgan Jones is one I can highly recommend. Its a fun read. With it you will start to learn how to read specs sheets and how to draw a load line, etc.
There are some good books to start with. "Valve Amplifiers" by Morgan Jones is one I can highly recommend. Its a fun read. With it you will start to learn how to read specs sheets and how to draw a load line, etc.
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