Boss DS-1 Tonestack

Thoughts on the Boss DS-1 tonestack

December 12, 2019

Like many guitar players, I also started my pedal collection with some Boss pedals. The first two pedals I ever bought were the DS-1 distortion and the SD-1 Super Overdrive. The DS-1 was sold just a few days after I got it. I just couldn't get a decent tone out of it w my setup, which was a Squier Affinity Strat and a cheap Laney Linebacker amp at that time.

A while ago I started buying some of these classics again to try modding them into something better. I discovered that the DS-1 was not as bad as I always thought, although there’s still room for improvement in many ways since it’s still too fizzy for my taste.

One of the things that drew my attention while modding was the tonestack. This is really a big part of the DS-1’s sound. The tone control on the DS-1 works very similar to the tone control of a Big Muff.

It’s essentially a potentiometer that blends between a high pass filter and a low pass filter. The stock cut-off frequencies are approx. 234Hz for the LPF and 1064Hz for the HPF. As you can see in the graph below there is quite a big gap between the highs and lows when the tone control is set at noon, which causes the scooped mid tones in a stock DS-1. It makes the pedal sound shrill and get lost in the bandmix. It’s really worth the effort experimenting with different capacitor and resistor values in the tonestack.

I prefer using the stock resistors with a 47nF capacitor in the LPF and a 33nF capacitor in the HPF. This brings the cut-off frequencies to respectively 498Hz and 709Hz. It’s still a little bit mid scooped, but the pedal cuts better through the mix and has definitely a lot more body.

Off course this is all a matter of taste!

By experimenting with the values you can get a flatter frequency response or even a mid boost. The closer the cut-off frequencies are in relation to each other, the flatter your response will be. By overlapping the cut-off frequencies somewhere around 500 to 1000Hz you will boost some mids.

You can also change R15 to let more or less highs get through from the HPF. If you increase the value of this resistor, there will be less highs coming through and vice-versa.

You could even replace R16 and R17 with 10k potentiometers to make the filters shiftable.

The sky is the limit!

Thanks for reading! Please let me know if you have any suggestions.