Stompbox distortion characteristics comparison

[Steben]

Anyone compared a TS9 with LED's to a BSIAB?
According to my spice adventures they respond identical at high gain and almost identical at low to medium gain!
Do they sound the same? LOL... Both seem to be in between overdrive and distortion.
Still haven't build the brown box, unfortunately.

[Xavier]

I wouldn't say a TS9 with LED's sounds like a distortion pedal. I used to have one in my pedalboard and imho it's well within the light OD territory still. Can't tell about the BSIAB because I'm just about to finish mine (I hope it works this time ), but I did build a mini booster and that itself is a distortion pedal. The BSIAB is two of them in series, somehow.... so I can't imagine they sound even close.

[aron]

SPICE must be wacked out! There's no way those two pedals even sound similar.

BUILD them, not sim them. (Just joking, simulators have their place).

[Paul Perry (Frostwave)]

Aron's right, SPICE can do some things, but distortion nuances aren't a strongpoint!
What would help, is for a "sinewave shootout".
Even better, a ramped sinewave shootout!!

[Steben]

SPICE must be wacked out! There's no way those two pedals even sound similar.

BUILD them, not sim them. (Just joking, simulators have their place).

Well, I like it for pre-DC-biasing, so you know "almost" what value that particular resistor will have.
It seems to work well.

But distortion..., yeah, it seems to me SPICE can't handle non-linear behaviour that well. With clipping diodes in the circuit it is acceptable however. The problem is active part - clipping etc...

[GFR]

Anyone compared a TS9 with LED's to a BSIAB?
According to my spice adventures they respond identical at high gain and almost identical at low to medium gain!
Do they sound the same? LOL... Both seem to be in between overdrive and distortion.
Still haven't build the brown box, unfortunately.

At what frequency? At what input level?

If I feed a 1kHz 1 V peak sine to both circuits, both will problably put out square waves

While Spice can't get subtle nuances of the non-linear devices, it surely will show you that a TS-9 won't sound anything like a BSIAB. But you have to do the right tests. Just as if you build the circuits and test them with a signal generator and a scope, it can also give you useless results.

[Steben]

yeah true enough. I was a bit surprised with my results too.
I haven't built the BSIAB yet, but there are enough sound clips around. 

[GFR]

At least with my quick simulations it's apples and oranges (click over the thumbnail):



The BSIAB has much more gain, and there's a frequency response peak at a much higher frequency. I used no tone controls for simplicity. I used 2n5457 for all the miniboosters since I didn't have a J201 model, so the actual gain is problably different (even higher?).

This matches well with the two circuits in question - the TS-9 being a slight overdrive with a midrangey tone, and the BSIAB being a heavy distortion with a "Marshall"-like presence.

Of course both pedals have subtleties that you can't spot in a quick sim like this and that may very tricky or impossible to find out even if you do a well planned and careful simulation, but the general behaviour of the circuits is well outlined.

[Steben]

I might add I was actually refering to the minibooster, not BSIAB.
sorry!
This may clear up a few things. The BSIAB is indeed double gain <-> minibooster.