Altec 436 Mods

[guavatone]

I did a NYD mod to the caps and PS diodes. Then I also changed the green .022uF c2 and c3 to Orange drops. The old green caps measured 0.15 uF out of the circuit.

Before the mod there was a certain mushy quality to the bass that reminded me of old recordings that I liked. Now it is gone, is it possibly the Orange drops or what? maybe just the value of .15uF did something different to the base.

Thanks dave for the great info.

BTW old junk inside old wires is nasty stuff, seems almost toxic too. and stinky

 

[leigh]

One simple mod I'm glad I did, because I use it the most, was to add a SPST switch to turn the compression on and off. With it off, it makes a colorful line amp/DI. Also helpful for figuring out if weird distortion I hear (on the attacks of notes) is from too much level, or from the compressor turning on and adding artifacts.

The switch interrupts the circuit between the "left" side (on the schematic) of the recitifier tube (the junction of pins 2 and 7 of the 6AL5), and the release controls (junction of R9 and R12).

Leigh