Sharing my Boss DS-1 mods for bass

[runmikeyrun]

Hey guys,

I've modded my DS-1 for better response with bass guitar, and while my mods are mostly nothing new, I just wanted to share them, done as a collective whole, for any current or future bass players.  Unfortunately I can't record a sound clip at this time, but take my word for it- it lets ALL the bass through.  There's also a tone stack mod for better mids and a gain boost mod.  Most of these mods were compiled from various forum posts and internet pages, but I felt that since I put them all together and it sounds awesome I'd share.

If you don't have it, schematic is here:
http://rh-tech.org/public/Boss_DS1_PG2.jpg

Bass boost control:  R16 (5.8k) limits low end as part of a high pass filter.  By replacing R16 with a 5k pot you can get back the lost bass frequencies.  With the pot at 0 ohms, you will get full bass response.  With the pot at 5k, you will get the stock amount of bass.  If you want to avoid the pot, you theoretically could just jumper this.

Changing input, output, and coupling caps:  Change C1, C2, C3, C5, C9, and C13 to 1uF.

Those are the two most important mods for getting more low end.

Raising the clipping threshold: Change C8 (0.47uF) to 0.22uF.  Stock the pedal starts to clip at 33hz, but with the smaller cap it doesn't start clipping until 154hz, letting some of those clean fundamental frequencies through and gives you a little dynamics and punch back. 

Tone stack mod for better mids:  Change C12 (0.1uF) to 0.047uF.  Adds 8dB of high mids (600-800hz) and 6dB at 300hz with the stock tone control at 12 o'clock.  Reduces the mid scoop effect.

Clipping changes:  A lot of people change to diodes on D5, D4, or both but I wanted more clipping than those had to offer.  Instead, I lifted one end of each pair of stock diodes (1N4148) and on D5 added a germanium diode in series (connected on the "right" side if looking at the board from the top).  On D4 I added another 1N4148 in series, but left them unconnected in the middle, here's why...

High gain/low gain switch: I ran a wire from each free end of the diodes to a SPST switch.  When the switch is on, the diodes are connected.  When switched off, the diodes in D4 are taken out of the circuit and there is a simultaneous reduction in distortion (almost none when the dist control is full CCW) and boost in output.  The DS-1 now acts as more of an overdrive, great for warming up (or slamming) a tube amp without the extra distortion of the pedal, which in my situation created uncontrollable feedback even with the dist knob full CCW.

Extra distortion mod: this will give you more available distortion on tap in the last 1/3 turn of the dist knob.  Change R13 (4.7k) to 1k.  The distortion gets crazy at max settings, so be careful!  Going any lower than 1k yields terrible results, the distortion is ridiculous and completely unusable.  So unless you're into that sort of thing stick with 1k as a minimum value.

[ds-2isthebest]

Hey another suggestion for a mod would be the fat mod. Its super simple, and removes that fizzy sound. it also ads tighter low end frequencies and takes off some highs, witch you might be looking for. You put a 150k and a 1k resistor on r9 and r6.

[ake7]

hi! thanks 4 the mod!
but... why the tone knob does'nt work after the mods?