Boss DS-1 Easy Mod

alex73013

New member
So, I picked up a Boss DS-1 yesterday. I found in stock form it sounded OK going into my Orange AD30 dirty channel with my dirty channel gain at 9 o'clock and the pedal's tone at 9 o'clock and gain at the lowest setting. When I had my Dunlop Echoplex Preamp set at number 8 going into the pedal it sounded pretty sweet. So, I was wondering what I could do to get more useable tones out of the DS-1. I stumbled on a forum that mentioned just clipping the D5 and/or D4 diodes as a mod. I went with just clipping the D5 diode. Wow! More useable gain control and overall sound. A bit more like a heavier overdrive pedal. It also boosted the volume a little more so I don't have to run the volume as high in the stock format. I know there are more mods to make it sound more amp like but I figured since I have an amp that excels at it's own gain that I wanted a pedal that would be more of a way to color my sound or boost my signal. I think this fits the bill. I think if I had the patience I would have put a three way switch and wired it to where I could toggle between stock, one diode and no diode. Or D5 on, D5 off and D4 on, and no diodes. I've heard good results of doing something similar with the Little Big Muff.

I will admit the DS-1 is probably not the finest sounding distortion pedal to most but I think it matters as far as the context and how you use it. I think people adjust the knobs by sight thinking that putting the tone at high noon will and putting the gain at high noon or all the way to max will give them their sound they're looking for. I think amp settings and the particular amp you use matters a lot as far as what guitars and pedals you should use with them to get a wide range of useable sounds. Just my two cents. I hope this easy mod may be of use to some people that have a DS-1 laying around just collecting dust.
 
Re: Boss DS-1 Easy Mod

Ahh, my first ever pedal! I scored a used original one in about 1983 and used it on its own into a cheap 50w combo and it sounded fine.
A little later I got hold of a cheap 6 band graphic eq and then it really came to life.
 
Re: Boss DS-1 Easy Mod

Ahh, my first ever pedal! I scored a used original one in about 1983 and used it on its own into a cheap 50w combo and it sounded fine.
A little later I got hold of a cheap 6 band graphic eq and then it really came to life.

Where did you have the EQ in the chain? I’ve been jamming on mine all day since my simple mod. It sounds so much better and it sounds awesome being hit with my preamp before it. I’m wondering what an EQ before it with certain frequencies boosted would be like.
 
Re: Boss DS-1 Easy Mod

If you are going to mod, put each side of the diode pair on a three way on-off-on switch. Silicon Diodes on one side of the switch, LEDs on the other (and no diodes in the middle) you get a few symmetrical and asymmetrical clipping options plus wide open.

After that, check out mods for the tone stack, especially more mids.
 
Re: Boss DS-1 Easy Mod

So, I picked up a Boss DS-1 yesterday. I found in stock form it sounded OK going into my Orange AD30 dirty channel with my dirty channel gain at 9 o'clock and the pedal's tone at 9 o'clock and gain at the lowest setting. When I had my Dunlop Echoplex Preamp set at number 8 going into the pedal it sounded pretty sweet. So, I was wondering what I could do to get more useable tones out of the DS-1. I stumbled on a forum that mentioned just clipping the D5 and/or D4 diodes as a mod. I went with just clipping the D5 diode. Wow! More useable gain control and overall sound. A bit more like a heavier overdrive pedal. It also boosted the volume a little more so I don't have to run the volume as high in the stock format. I know there are more mods to make it sound more amp like but I figured since I have an amp that excels at it's own gain that I wanted a pedal that would be more of a way to color my sound or boost my signal. I think this fits the bill. I think if I had the patience I would have put a three way switch and wired it to where I could toggle between stock, one diode and no diode. Or D5 on, D5 off and D4 on, and no diodes. I've heard good results of doing something similar with the Little Big Muff.

I will admit the DS-1 is probably not the finest sounding distortion pedal to most but I think it matters as far as the context and how you use it. I think people adjust the knobs by sight thinking that putting the tone at high noon will and putting the gain at high noon or all the way to max will give them their sound they're looking for. I think amp settings and the particular amp you use matters a lot as far as what guitars and pedals you should use with them to get a wide range of useable sounds. Just my two cents. I hope this easy mod may be of use to some people that have a DS-1 laying around just collecting dust.
Think you are right about folks using their eyes to set the knobs. Being a mostly OD type of guy, I 1st set the DS1 to zero on the drive. Works well for me there...sounds like classic rock lead tone with delay after. I have no use for anything after noon on the gain...lol

Sent from my SM-G920V using Tapatalk
 
Re: Boss DS-1 Easy Mod

I'd say remove the clipping diodes and replace them with red LEDs. Gives it a much more usable volume control and softens the hard clipping.

I did the Monte Allums tri-gain recto mod and all the other mods seem extraneous.

I might buy another DS-1 eventually and do this as mine developed some noise over the years.

Sent from my SM-G960U using Tapatalk
 
Re: Boss DS-1 Easy Mod

I'd say remove the clipping diodes and replace them with red LEDs. Gives it a much more usable volume control and softens the hard clipping.

I did the Monte Allums tri-gain recto mod and all the other mods seem extraneous.

So, is this an "accessible" mod to a soldering hack like myself? Is there a Youtube vid on how to replace the LED's or do the mod???
 
Re: Boss DS-1 Easy Mod

So, is this an "accessible" mod to a soldering hack like myself? Is there a Youtube vid on how to replace the LED's or do the mod???
On the board there are 2 diodes side by side in opposite directions. I think they are D4 and D5. Unsolder them as cleanly as possible and replace them with LEDs. Keep in mind that they must be in opposite directions for it to work right.

I believe that the original diodes choke (for lack of a better term) down the volume throughput so the pedal sounds quieter.

Sent from my SM-G960U using Tapatalk
 
Re: Boss DS-1 Easy Mod

Yes the original silicone diodes clip at ~.7V, the red LEDs clip at ~1.2V, the clipping is what limits the output, so yes, it will be louder and more open with LEDs.
 
Re: Boss DS-1 Easy Mod

What does the Fat Mod do exactly? Are they subtle or do they alter the character of the pedal?

The Fat Mod lowers the bias of the input transistor. In the stock form, it's biased pretty hot and is clipping. The lower bias stops it from clipping which results in a cleaner signal through the next stage of the circuit and ultimately make it warmer sounded. Not buzzy and sharp. Really usable. I have not tried the JCM800 mod so I cannot comment.

I will say this, the solder pads on the DS-1 can lift pretty easily if you are not careful. They get too hot and that's it. It doesn't ruin it, but means you'll have to use a jump wire from that point to the next with the pad gone. If you're not comfortable with soldering pedal circuits, I wouldn't advise working on the DS-1. Speaking from experience and I've been soldering since I was 16 and learned better technique from a Naval engineer in the early-mid 90's. A desoldering braid work great.
 
Re: Boss DS-1 Easy Mod

I did some further research and it appears that the JCM 800 mod for the most part reduces the pre-distortion bass, so that the overall signal coming out isn't as splatty. If the Fat Mod decreases harshness, I can see why people do the two together, as those are two of the biggest problems with the stock DS-1.

I've also heard that I should replace the stock op amp with a double op amp. The guy basically said that it was "objectively better" regardless of other parts of the pedal, so I'm kind of skeptical. What can I expect from doing the change?
 
Re: Boss DS-1 Easy Mod

He means a dual opamp. But the DS-1 has had a dual opamp since 1994. The original from 1978 until 1993-94 had a single opamp. Now, in regards to the dual opamp chips used, difference is that the pins are all inline rather than 4 to a side (looking like a bug). A dual opamp has inverting and non-inverting inputs and an output with each of those, regardless of the form factor. The opamp used in the DS-1 has changed numerous times since it's introduction, with the first opamp change coming in 1994. The current opamp used since 2007 is NJM3404AL. There may have been another change since but I haven't found anything saying otherwise.

Swapping it out can be fairly straightforward so long as the pinout on the replacement matches what is in there now. Not all are the same in that aspect. Depending on how the opamp is utilized, you might hear a little bit of a difference. Quality components and changing the diodes has a much larger impact, IME/IMO. The Fat Mod makes it more overdrive like, which I like, but with less mids. There are other changes that can add more mids.
 
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Re: Boss DS-1 Easy Mod

The easiest way to improve a DS-1 is to change the tone stack. Screw around with R17 and C12 to adjust what frequencies the tone knob effects and the rest of the pedals golden.
 
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