Rat-related questions

[lykwydchykyn]

I just finished a build of a Rat using the diode-compression op amp, and I gotta say it sounds killer.  A couple questions I had though:

- Does anyone know what the actual slew rate of this design is, or how I might estimate it?  I'm guessing it's gloriously low because I'm getting no squeals from my rat like I would with a high SR op amp.

- I didn't seem to miss a compensation cap, but if I were to use one I'd guess (based on some quick reading) it goes between the base and collector of Q3 (the output transistor), is that correct?

[ElectricDruid]

Have you got a schematic please? I'm not familiar with "the double compression op-amp" and I don't remember a Rat circuit with such a thing.

Once we're on the same page, we might be able to help you with your queries.

Thanks!

[lykwydchykyn]

Not a "double compression op amp", a "diode compression op amp" -- as in the topic of this sub-forum.  The Joe Davisson Diode compression op amp.  Guessing you're reading this outside the context of which forum it's in.

Anyway, here's the op-amp schematic: https://www.diystompboxes.com/analogalchemy/sch/diodeopamp.html

[ElectricDruid]

Not a "double compression op amp", a "diode compression op amp" -- as in the topic of this sub-forum.  The Joe Davisson Diode compression op amp.  Guessing you're reading this outside the context of which forum it's in.

Aah! Yeah, I am! I got here by looking at "unread posts", so I didn't notice the context. My bad, sorry.

Anyway, here's the op-amp schematic: https://www.diystompboxes.com/analogalchemy/sch/diodeopamp.html

Dunno, sorry. If it were me, I'd put the schematic in LTspice and see what happens. People more versed in transistors might be able to tell you by simply looking at it, but I don't have that kind of familiarity.