Best Post-EQ Clean Boost Stage Option

[BennyBoy]

Is it okay to run R8 to ground instead of Vref, or is that necessary for operation?

As drawn, it has to be Vref. If you add a cap below R8, you could take the bottom of the cap to ground. I actually did that in the stage that followed that one I just posted:



(All these bits are from my Hard Bargain distortion article if you want to take a look)

R8 at 10K with 220n like the above schematic would give you a highpass at 72Hz, so that's about the minimum value you should use for the cap. 470n would be another octave lower (roughly) so 36Hz, which is already plenty low.

Awesome, thank you! Trying this today, much appreciated!

[BennyBoy]

Is it okay to run R8 to ground instead of Vref, or is that necessary for operation?

As drawn, it has to be Vref. If you add a cap below R8, you could take the bottom of the cap to ground. I actually did that in the stage that followed that one I just posted:



(All these bits are from my Hard Bargain distortion article if you want to take a look)

R8 at 10K with 220n like the above schematic would give you a highpass at 72Hz, so that's about the minimum value you should use for the cap. 470n would be another octave lower (roughly) so 36Hz, which is already plenty low.

How does this clean boost output stage look? I went with your values but used a 1uF for the cap tied to R8 (in your original schematic you posted). Figured although 470n would be big enough, I might as well use 1uf because it is so common through out the rest of my circuit.

[BennyBoy]

I assume this is about as transparent as you can get with an op-amp gain stage like this, right?

[ElectricDruid]

How does this clean boost output stage look?

Yeah, that looks good.

I went with your values but used a 1uF for the cap tied to R8 (in your original schematic you posted). Figured although 470n would be big enough, I might as well use 1uf because it is so common through out the rest of my circuit.

Entirely reasonable.

I assume this is about as transparent as you can get with an op-amp gain stage like this, right?

Yes, I'd say so.