Boss DS-1 Monte Allums Mod

[duhvoodooman]

After reading lots of positive comments about the various Monte Allums mods for various effects pedals, I decided to check out one of his mod kits for myself. One that looked particularly interesting is what he calls the "Rectifier Tri-Gain Plus" mod for the Boss DS-1 distortion pedal. The mod consists of three elements:

1. A 3-way toggle switch for diffferent clipping choices--1N4002 silicon diodes (a little more aggressive than the stock diodes, which are a different silicon type), red LED's, and a "diode-lift", i.e no diode clipping, so it becomes just a high-gain preamp boost.
2. Several replacement caps for the PCB of better quality and with slightly higher ratings to give better fidelity and punch up the stock pedal's weak bass & lower mids.
3. A socketed IC replacement for the stock IC, fitted with a hi-fi Burr-Brown opamp to improve overall clarity and reduce noise.

I bought a used DS-1 on eBay for a mere $20 (another reason I picked this particular mod to do!), which arrived yesterday. Cosmetically, it's pretty beat up, but it's 100% functional electronically, which is what I really cared about. The mod kit arrived a couple of days before, so I dug right in. The directions that he provides are pretty good, and this mod is quite straightforward to do. At this point, I have all of the PCB mods done, and the switchable clipping diodes are all wired in. All that I have left is to drill a hole in the side of the casing for the toggle switch and then reassemble the pedal.

Since it's electronically complete, I gave it a quick test this morning through headphones (everybody was still sleeping), and it works perfectly. I won't know for sure until I hear it through the amp speaker tonight, but it sure sounds like it's got a TON of balls now, with a much more balanced bottom & middle vs. the stock sound. In particular, the red LED's have a big, Marshally in-your-face tone that's reminiscent of my Guv'nor 2 pedal with the gain cranked up.

Before starting the mod, I recorded a clip with the stock pedal to demonstrate its natural tone, using both my LP Std. and Strat. I'll do a similar one with the modded pedal, and post a link here so that everyone can hear the difference. Just as I'd read about the DS-1, I found that the stock sound really pushes the treble & upper mids, and is quite harsh & brittle sounding. It's not a pedal I would be interested in owning in stock form. Hopefully these mods turn it into a keeper. More to come....

 

[duhvoodooman]

Can't wait to hear some clips, hint, hint

Workin' on it. Patience!

What is the green PCB for?

That's an adapter to be able to use the 2x4 opamp/socket with the 1x8 pin socket array on the DS-1 PCB

Gotta go drill that hole for the switch now....

UPDATE 1/10/08: I finished up the DS-1 mod last night, mounting the 3-way clipping mode toggle switch on the left side of the pedal, adjacent to the output jack (see stock DS-1 image below). The directions suggested mounting it up through the top of the pedal, just below the Tone knob. However, this would have entailed drilling right up through the "Tone" label on the housing and would make the mod look kind of amateurish, I thought. The risk of running the switch out the side is that it's less well protected there. So if you tend to bang your pedals around or move them a lot, you'd probably want to follow the suggestion to go through the top.

I didn't have the time last night to get into recording the "after mod" clips, but I did spend a few minutes playing my LP Std. through my Fender Blues Junior with it. The mod certainly seems to have filled out the pedal's tone, making it less treble-heavy. It's still a pretty raw sounding distortion, considerably edgier in tone than my Marshall GV-2 Guv'nor Plus or even the modified Rat clone I built. The treble/upper-mids component of the distorted tone is still pretty dominant , but the mods have strengthened the bass and lower-mids to give a fuller and more balanced sound. The premium Burr-Brown opamp does indeed seem to keep the tone very sharp and focused.

The two different clipping modes function as expected, with the 1N4002 silicon diodes giving a more typical DS-1 tone, while the red LEDs give a bigger, deeper and very noticeably LOUDER tone, with less outright distortion. This makes sense, since the LED's higher voltage threshold means that they clip less of the signal. I also tried the switch's middle position, the "diode-lift" mode, which takes the clipping stage right out of the signal path and turns the pedal into a preamp boost. This position is even louder than the LED's, since no portion of the signal is being dumped to ground by clipping diodes. It reduces the distortion, but certainly doesn't eliminate it, since the signal into the amp is boosted so considerably, analagous to dialing up the preamp gain in the amplifier itself.

I'll try to record those "after" clips tonight, or over the weekend, at the latest. Then you can hear the impact for yourself....

 

[mrmudcat]

Hey brother not sure how ive missed this post. Ive been ill lately:thwap: I have a few pedals modded with monte's stuff.I actually lived close to him in mississippi(30 miles).

My uncle guess preached at the crossroads church and that is how we connected.I have a ds1 waiting on this mod just no time lately. Im curious as to real world sound :rockon: Anyways not sure if your familiar with any other stuff monte puts out.The solid copper sheilding sheets,e-nutt, and also guitars.
(well worth a look for anyone) I have not talked to monte since the summer and havent even been to the new site you linked.Thanks for the thread as im bored and I think im going to finish a few things.Peace brother!:AOK:

 

[sunvalleylaw]

Excellent! I may have to try that on my own. I am getting used to using it more and more as stock, esp. in combination with the Monkey, which seems to smooth out the square waves it is sending (I got that info from Sir Spud). But a cool mod like this would be fun, and make it more versatile on its own. Thanks for being our resident pedal pioneer!

 

[Tone2TheBone]

I got to hear the before clip and I gotta say that pedal needs modding BAD! Go Voo go!

 

[M29]

Hello,

I have done this mod but without the optional opamp & socket and I feel pretty much the same. The biggest improvement I found was in the overall frequency response as my DS-1 was very thin sounding before the mod.

One issue I noticed is that it does not seem to sound as good connected to a pedal power supply. It sounds different then with the battery. This may just be my pedal or my ears although I have not taken the time to check this out thoroughly yet.

M29

 

[duhvoodooman]

One issue I noticed is that it does not seem to sound as good connected to a pedal power supply. It sounds different then with the battery. This may just be my pedal or my ears although I have not taken the time to check this out thoroughly yet.

That's interesting; I'll have to check that out. I've only run it with an AC adapter, thusfar. I'm not big on 9V batteries....

 

[duhvoodooman]

Okey-doke, below is a link to a clip I recorded using my Epi Elitist LP Std. from the bridge pickup into my Fender Blues Junior, with the latter set to a fairly clean tone (pre-amp volume at 3). Other than the DS-1, there are no additional effects other than a bit of reverb. This guitar/pickup combo demonstrates the effect of the mods most clearly. I also did some recording using my Strat on the neck pickup, but a hotter and more trebly signal definitely does a better job of showing the tonal differences. One note--I recorded the stock DS-1 portions a couple of days ago, and the modified portions today. There's more reverb in the modded recording, but it doesn't change the tone, just makes those parts sound a little more "spacious".

There are a total of 7 pairs of riffs played in the following sequence:

1. Clean, DS-1 off
2. Stock - distortion control set at 11 o'clock (~40% of full gain)
3. Mod/silicon clip mode - distortion control set at 11 o'clock
4. Mod/LED clip mode - distortion control set at 11 o'clock
5. Stock - distortion control set at 3 o'clock (~80% of full gain)
6. Mod/silicon clip mode - distortion control set at 3 o'clock
7. Mod/LED clip mode - distortion control set at 3 o'clock

Take a listen and see what you think. Here's the clip link (~1.4MB, runs about 1:30):

http://www.box.net/shared/3ahaqx3k84​

 

[Adrian30]

I'm finding the second sequence -2. Stock - distortion control set at 11 the harshest and the least compelling. In my opinion, the mods improved the tone dramatically. Another score, DVM.:AOK:

 

[Ascension]

I have done several of the Monti Mods including the Rec Mod on the DS-1. Of the Mods I have done that one was the mildest changing the pedal the least. I havent tried the mod you did.
Right now I have a pair of CS-3's with Monti mods (1 standard and 1 the opto ) and a BD-2 with the H2O. The best one was the MT-2 Sustainiac Mod. That one turned a real TURD of a pedal into a Boogie in a box!!!
So far I have done the T-Von CS-3 standard and opto mods, MT-2 sustainic mods, SD-1 mod with the bypass, DS-1 Recto mod and the BD-2 H2O.

 

[Adrian30]

I have done several of the Monti Mods including the Rec Mod on the DS-1. Of the Mods I have done that one was the mildest changing the pedal the least. I havent tried the mod you did.
Right now I have a pair of CS-3's with Monti mods (1 standard and 1 the opto ) and a BD-2 with the H2O. The best one was the MT-2 Sustainiac Mod. That one turned a real TURD of a pedal into a Boogie in a box!!!
So far I have done the T-Von CS-3 standard and opto mods, MT-2 sustainic mods, SD-1 mod with the bypass, DS-1 Recto mod and the BD-2 H2O.

How about the H2O mod on BD-2? Are you happy with it? Is it, in your evaluation, "smoother, more transparent and dynamic etc,etc..." as described on their (Monte Allums) website?

 

[F_BSurfer]

Sounds good DVM how do you think it compares to your rat clone this has got me thinking of picking up a DS-1 and doing the mod or just getting his mod for my Pro Rat

 

[WackyT]

Just picked one up off eBay for $20+$10. Pretty funny the mod kit costs more than the pedal itself.

 

[duhvoodooman]

Sounds good DVM how do you think it compares to your rat clone this has got me thinking of picking up a DS-1 and doing the mod or just getting his mod for my Pro Rat

Well, the mod for the Pro Rat says "Sold Out", so you may have to go the DS-1 route or pick another pedal that Monte offers a kit for.

To answer your question about the modded DS-1 vs. my modified Rat clone, I find the DS-1 edgier/rawer sounding with a stronger emphasis on the high end. The Rat, to me, has a smoother sound, with greater overall sustain and more emphasis in the mid-range than the DS-1. If I had to choose one over theother, I'd go with the Rat. YMMV.

 

[Ascension]

How about the H2O mod on BD-2? Are you happy with it? Is it, in your evaluation, "smoother, more transparent and dynamic etc,etc..." as described on their (Monte Allums) website?

Yep it was all of what was promised! The mod got rid of that nasty SPLAT that the pedal had stock. On the mod kits I have done the BD-2 was the most difficult. That's because of the second circuit board on the BD-2 it takes a little extra work to change the caps on that board.

 

[M29]

Ascension,

I have had the MT-2 sustainiac mod setting here for about 5 months. From what you have said I am now looking forward to making the mod.

M29