Booster 2.5, Sweet Thing, BSIAB ?

[nooneknows]

Hi
I'd like to know what kind of flavour the three circuits, compared, have.
The circuits are pretty similiar and I know they sound Marshall-like, but I'm interested in a plain medium distorsion without particular color (no mid sccop for example), I 'm not sure what have I to build.
Thank you in advance for your help.

[Ed G.]

The Sweet Thing and BSIAB use a fifth fet as a source follower which gives more compression and sustain.
I changed a cap on the BSIAB which made the first stage like a treble booster, and gives it a marshall sound.
The BSIAB and 2.5 have big muff-type tone stacks. The sweet thing has a cool tone control that affects the midrange in a really effective way. You can go from modern 'scooped' tones to more classic midrange tones.

[nooneknows]

Thank you!

I was wondering what kind of influence the R470K//C470pF could have, apart diming down the volume to the second stage.
I was thinking about putting a single 500K/1M pot between stages without the partitor resistor (without coupling cap too?) and using a Marshally R820//0.68uF instead of the R100 resistor of the first stage.
Any idea?
If I'll have time I'll try something during this week
thankx

[Ed G.]

Thank you!

I was wondering what kind of influence the R470K//C470pF could have, apart diming down the volume to the second stage.
I was thinking about putting a single 500K/1M pot between stages without the partitor resistor (without coupling cap too?) and using a Marshally R820//0.68uF instead of the R100 resistor of the first stage.
Any idea?
If I'll have time I'll try something during this week
thankx

That R/C combo makes a high pass filter, which reduces the bass from the first stage. It tightens up the sound a good bit. You'll find this HPF in Marshall schems also.