WSW 601-431 / WSW 601-432 Clone / inspired Limiter

[Falk]

I was given 6 RFZ V740/1cy lately. Those are 40dB universal line amps. They can be easily modded to 65dB gain. Impedance is switchable between 600 Ohms an 5k Ohms. I thought of using them as mic pres but then again I have enough around.

I remembered this post https://groupdiy.com/index.php?topic=70972.msg904493#msg904493
where a member published a schematic of a WSW limiter which uses a universal line amp module as gainstage aside of a rather simple limiter circuit.

Since WSW units are more or less critically acclaimed, I thought of building a clone with the RFZ modules.
The 601-432 uses a diode array ca3039 instead of discrete diodes as the 601-431. Reading the manuals of the both, the 431 seems to be more accurate and has much less THD. Also the -432 is stated as effects limiter and channel limiter rather than being for the mix bus where I would intend it to use.

Does anyone know the tonally differences between the -432 and the 431? Do you think its worth the work to build another diode limiter? I already own a Zener Clone which sound is too special for mix bus duties.

I appreciate your input. Thank you.
Falk

I attach a schematic drawn and published by garshlab.com here on GDIY.

 

[Falk]

Here is the schematic of the -431 which I assembled from single page scans from the web. I hope its correct.

https://www.dropbox.com/s/yl9uq3eawpe9d4c/WSW_601431A_schematic.pdf?dl=0

 

[dirty1_1garry]

Feel free to contact if you need help)
Mine 50cents - in redrawn schematic I forgot to delete transistor values (BC550, 560 etc...), just used as reference with correct schematic pnp/npn placement. Exact transistor types and nowadays equivalents should be checked more precisely.