Federal AM864 - My build

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Attack/release are 1meg and 2.2.mfd...my ear says it is right for singers...I won't track with it right away...just Chanel patch it on return til I get to know it better :)
 
The description you are making for the audio seems right on. I've had an original one and built a clone years ago, which ended up as a donor for other projects. But I have plans to build another one some day from scratch parts. IIRC it wasn't very subtle and quite agressive but yet sounded a bit wooly somehow, very tubey. Nothing like an opto or a 6386 varimu, but def a lovely useful color in my setup.

Re the finish, I did some research and apparently you can get that with high temperature wrinkle paint... It's pretty expensive and needs baking but should look cool. I'll give it a try soon on a STA level clone, hopefully.
 
.need to explore my control voltage as it is high compared to manual specs
Here's a quote from PRR
"However the "current control" is your main control of knee sharpness and ratio. If you set it to zero volts, it has a very soft knee and low ratio. For limiting, you have to set it to a fairly high voltage. For high-ratio limiting, maybe near 20V. It wasn't made to do that, as shown by the pretty lame control amp. I suspect 2 or 3 volts gives a good range of no-action, and above that a range of lower dynamic range. If you are compressing clean tracks for effect, maybe you want compression to start early and soft, so 1V might be your setting."
 
Thank you very much for all this info...my control voltage is at 11 when the 1ma meter is at 1.0 if I get it down to 3vdc the meter is so low on the scale it is useless...unit sounds 'cleanest' up in the 8 to 100 range...I need to make an h ad for the 2 volt audio meter as I don't want to fry it...I tried tying a 600 ohm resister across it but that certainly did not help the sound quality. I should pull the 6sq7 to see what it sound like w/ no gr....I do like this thing@@...thx
 
thanks for the info, i'll keep it as my next project.

The description you are making for the audio seems right on. I've had an original one and built a clone years ago, which ended up as a donor for other projects. But I have plans to build another one some day from scratch parts. IIRC it wasn't very subtle and quite agressive but yet sounded a bit wooly somehow, very tubey. Nothing like an opto or a 6386 varimu, but def a lovely useful color in my setup.

Re the finish, I did some research and apparently you can get that with high temperature wrinkle paint... It's pretty expensive and needs baking but should look cool. I'll give it a try soon on a STA level clone, hopefully.
can you post link or examples of the paint job? what is wrinkle paint? what's the purpose of baking?
 
The finish on this salvage front panel has a kind of sandy grit in it...I think the panel is low grade steel as it chewed up my titanium drill bit..here is my best picture ... my 1 ma meter for gr does not have polarity marks on it and I may have wired it backwards ? Ain't this fun ;- )
 

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