SD1 - mod questions

[andthenurse]

I bought a Boss SD1 for twenty quid off ebay - worth a punt for that, I thought. It sounds pretty good with my Strat into a VibroChamp and Deluxe Reverb, but I wondered if it may be worth modding? Anyone know of mods it might benefit from?

 

Ta

[Web Surf]

Where do you feel it could do with some improvement ?

 

More Bass / Less Bass ?

 

More Treble / Less Treble ?

 

More Sustain ?

 

More gain/ less gain ?

 

Want a scoop / dont want a scoop ?

 

Symetric / Asymetric clipping ?

 

Softer clipping ?

 

Tell us what you want and maybe we can suggest some changes !!

[El-Lardo]

I did this mod to mine about 5 years ago.

 

It's been my go-to overdriver ever since.

 

Sounds better than either riTS-9 or FDII

that I've tried.

 

Smooth.

[lp_man]

http://www.geocities.com/overdrivespider/index.htm

 

I havn't got around to doing clips yet, but once they are done they should help you make a decision. I personally love SD-1s! Bloody amazing pedals once modified

[lp_man]

Done two clips comparing the Fulldrive and the Keeley mods but havn't got around to updating the site yet. In both clips the Keeley goes first then the Fulltone II conversion.

 

Clip one:

Level: 12 o'clock

Tone: 2 o'clock

Drive: 12 o'clock

http://www.soundclick.com/bands/songInfo.cfm?bandID=452640&songID=4335213

 

How I usually set my SD-1's nice AC/DC type tone with a bit of treble added through the tone controll at 2 o'clock.

 

Clip two:

Level: 12 o'clock

Tone: 12 o'clock

Drive: 12 o'clock

http://www.soundclick.com/bands/songInfo.cfm?bandID=452640&songID=4335220

 

Using completely flat settings the SD-1 bas more bass and a smoother tone.

 

Hope that helps!

 

-Will

[andthenurse]

many thanks to you all, food for thought there.

 

The more I use it, the more I like the SD1 - my favourite sound with it is level at 12 o'clock, tone at 10, drive at 9 through a fairly cooking VibroChamp

[Web Surf]

 

Originally posted by lp_man Done two clips comparing the Fulldrive and the Keeley mods -Will

 

 

 

very minor "differences"

[lp_man]

Originally posted by Web Surf very minor "differences"

Thought the same thing. I think the main difference in sound is due to the clipping diodes in the Fulldrive converted SD-1 compared to the Sillicum ones I put in the Keeley. The Fulldrive has a germanium and a 1n4001 in series in case you were wondering

 

Edit: In the Keeley modded SD-1 I used 1N4148 diodes, they are on a switch with some NOS germanium ones so I can toggle between the two. All clips were done with the 1N4148 though.

[Web Surf]

Mr Keen noted somewhere that the pre-equaliser and post equaliser around a distortion stage make a very big difference to the overall sound.

 

That is a very keen observation !!!

 

 

There are many "Amplifier modellers" that are nothing more than a per-dist equaliser, distorter and a post-dist equaliser

 

 

Now when we do these mods, changing diodes makes a very small chage the shape of the distorter. If the gain is very high, the exact shape of the clipper does not make a difference.

 

( Suppose we have two clippers, both cut voltages above 2 volts. One has a soft curve, one has a hard curve. We drive it with a gain of 3000. A 50 mV signal will become a 150V signal if it was not clipped. So we see that the signal will get clipped very rapidly indeed. Then the "soft clipper" and the "hard clipper" both sound the same !! tonal differences will only be seen with gains around 10-50)

 

 

 

 

Adding a few extra diodes one one leg make a bigger difference in converting symetrical clipping to non.

 

but the big thing, the tonal characteristics of the stages before and after the diodes remain the same.

 

 

A few strategically placed caps that change tonal response will have a greater effect in modding a fuzz than a pure change of diodes of one type to another.

 

( love your work !!!)