Monte Allums Boss CS-3 Mod

This was my very first electronic project. I look far back now and regret this noob mistake. Boss knows what they are doing and if someone tells you otherwise ask them why Boss has not hired them yet.

Er... really easy for me, as I took the pedal & new parts to an electrician for him to do as I have hands of concrete. I was charged for the service but I know it's done right.

I like to play a nice clean tone through chorus to a 100 watt HH solid state combo, so I bought a stock CS-3 many years ago. I thought this would help improve my tone. I ended up trading in the CS-3 for something else as the background hiss was really annoying & the pedal didn't really seem to do anything except make a mess of my sound.

Anyway, when I saw Monte's opto-mod on eBay I got a used CS-3 from eBay, from someone who was probably as sick of his/her CS-3 as I'd been the first time I had one. I tried it: it worked fine, but the bad points of the pedal swiftly came back to me.

I quickly ordered Monte's opto-mod & it took about a week to reach me in the UK from the USA. Off to the electrician I went & it took him about a week to do the mod.

On trying the pedal for the first time: simply jaw-dropping. The clarity, the lack of the annoying hissy noise, the improved sustain, the snazzy new bright blue LED. In a nutshell, it's improved my tone to such an extent that I'm surprised Boss dare sell the stock CS-3 as it is at all. I can't imagine playing without the mod-ed CS-3. This is possibly the best (& cheapest) thing I've ever bought for my guitar sound.

I own a few other pedals that Monte has mods for (RAT 2, MT-2, OD-3 etc) & I'd definitely consider getting more mods from him. However, Christmas is coming so they'll have to wait until next year!

I have full confidence in the chap that did the mod for me & no hesitation in giving this a score of ten.

A really friendly guy: I was initially sent the incorrect mod kit (for a Boss DD-5). As soon as Monte got my e-mail telling him he apologized wholeheartedly, said I could keep the DD-5 mod kit & sent my CS-3 kit straight out. What a guy! He's also full of helpful advice & an all round good chap. Cheers, Monte!

Simply stunning mod for an insanely cheap price (especially with the ?? to $ exchange rate as it is). Only ??12.11 including postage/carriage. I can unreservedly recommend this CS-3 opto-mod.

Bought this pedal used from eBay, in great condition. Easy to use. Making the mods were easy as pie. Good instructions and good support.

This pedal does what it's supposed to do. With the Monte Allums mod, it really makes a big imporvement in overall sound. Most noticeable at first was the absence of noise when the sustain is turned up. The true sound of my guitar comes thru when stomping on this pedal. No deteriorization of tone at all. Aside from the added sustain and compression, the tone is not colored at all. This is what this pedal is supposed to do.

It's a Boss. I've owned several for a long time. Never any problems.

Good support. I sent an email after being sent mod instructions for the wrong Boss pedal. He answered immediately with the correct attachment. No big deal as instructions are also sent with the parts.

I play everything, but blues is my favorite. Been playing almost 40 years, and own too much gear to mention. I like Boss and Roland products, always have. They do a great job of adding a little color to the guitar sound. I try to let my fingers do the rest. I was so impressed with the result of the mod that I purchase the mod for the Boss BD-2 (H2O) and the CE-2 as well. Please read my postings for those as well. Performing the mods was pretty easy. Instructions are very good. Just take your time, and follow all the instructions. I was an electronic tech for many years, and was very comfortable making these mods. It was a piece of cake. I don't think I spent a half hour on each mod. Read all instructions first, start to finish, so you know what to expect and what's involved. Then follow, step-by-step. You'll end up with a nice pedal. It's well worth the $20-or-so he charges. Price of a resistor, a few pennies. Price of a good cap, a few more pennies. Price of an extra bright led, a nickle. price of a few diodes, solder, wick, etc, a few bucks. Having a pedal that helps you produce a sound that makes you smile, priceless ... Nice engineering work.

DIY CS-3 OPTO Mod install was pretty easy and fun. All monte instructions are excellent. And the pedal sounds TONS better. I was shocked to hear (and feel) the difference. GREAT MOD.

Unbelievable improvement over the stock pedal. Some of my old pals who had not heard me in awhile were stunned. At a recent jam one comment was, "I don't wanna play my rig, let me use yours instead because it sounds like the record". Been playing roots, rock, country stuff for decades in bands. Les Paul, strat, tele into all-tube amps of varying size depending on venues. 4 watts - 130 watts.

Gigging most every week or so. Big gigs & little gigs. No problemo.

This pedal is transformed by this mod into a great HI-FI quality compressor. Oh... and the LEDS are cool. So bright you can see them in the sun (outside gigs) or when all the lights are pointed at you.

From start to finish, it took me about an hour to get the mod installed. 10 minutes to set up and wait for my soldering iron to heat up, and 50 minutes of replacing pieces one by one. The instructions state very clearly that you should replace each component one by one, rather than remove everything and then replace everything so that you can test it in between each replacement. This is a good idea because if you get everything on and then fire it up and it doesn't work or sounds lousy, you won't be able to easily narrow it down to a single culprit. If you take your time and have a well-lit work area, this can be a fun afternoon project. Bonus points for including solder and wick.

I have to be honest, the CS3 is the only compressor I've ever used other than the ones built into the Pod XT Live. The stock CS3 is kind of lame, and I never really found a use for it other than adding a little bit of boost or for mellowing out chords, but it affected the overall volume to make me trust it in the middle of a song.

The Opto Modded CS3 is an absolute dream. Notes come in very smoothly, and sustain is very very clean. I can't wait to use this for solos with the band. It makes me want to play more Knopfler and Gilmour-esque stuff.

If your solders are good, a modded CS3 should be every bit as reliable as a regular Boss pedal. No worries here.

After installing the mod and trying it out at higher volumes on my amp, I noticed a fair amount of hum and distortion that I did not notice before. I went back and triple-checked my solders and components, and everything looked alright, so I sent an email to Monte asking if there was anything else I should check. I figured out the problem before he wrote back (it needs an ACA power adapter, not PSA), but when Monte wrote back, not even a few minutes later, he told me how to rewire the pedal to work off of a regular PSA adapter. When you buy a mod like this, you're not just getting a couple of Radio Shack parts in a bag, you're paying for the research that went into the mod and the support you get in case something goes wrong.

In my opinion, the stock CS3 is pretty lame, and doesn't do enough to warrant the floor space that it takes up. Adding these mods makes it a powerful performer and something that I actually want to use. Reading all of the reviews, I was skeptical, thinking that everyone was just patting themselves on the back or something, and that I'd have to really work hard to convince myself that there was a difference at all, aside from the blue-white LED. I just want to say that the difference is real and amazing. If you've got a stock CS3 that spends its time on your shelf because you can't get it to do anything worthwhile, buy this mod. I'm curious to see what the other Monte Allums mods will do for some of my other pedals now.

I'm not electronically proficient. This (and a couple other allums mods) was my first attempt at anything like this. It probably took me three hours. Some parts were hard to get at and I probably said some curse words along the way but if you're patient, it will be worth it!

Outstanding. I also did the Dyna Comp mod on a vintage Dyna Comp. I like the Dyna Comp mod a lot but after a couple months, I'm pretty sure I like the CS3 mod better. The Dyna Comp hasn't seen much action lately. The CS3 is not as cloudy. I like softness some places like in tube amps and analog delays but for compressors I don't want to overly color the sound that I've tried so hard to perfect. Well, it's not PERFECT but you know what I'm saying. Also, I like a very fast attack/ subtle compression and the CS3 is better at this than the Dyna Comp in my opinion.

The CS3 sounds like crap when it's running low on batteries so either be prepared to replace them often or get a power supply.

Monte is awesome. I emailed him so many times, I can't believe he responded to each of them. In the middle of the install, I emailed him some pics of a place I thought I screwed up and he got right back to me and explained why it was cool and not a screw-up.

Very nice.

This all depends on your soldering skill level. Soldering is something that you can learn in a day, but to master it takes a bit more time. It is a mechanical art form, just like any other, and it just takes practice. If you can solder, then you can do this mod.

Luckily, if you screw up, you can always use the desoldering braid.

Before doing the CS-3 Opto mod, I saw no reason to use my CS-3, except perhaps as a paperweight. The hiss alone was reason enough to keep it off the pedal board. Now...I could never do without it. I have been playing with it...playing a familiar tune with and without the CS-3 Opto...you really need to just try it for yourself to understand. And I don't claim to have much experience in compression technology, and I haven't ever used anything but the CS-3, but I do know what sounds good, and this CS-3 Opto sounds f'n great!

It's a boss, it should theoretically last forever. However, I am slightly concerned about all of the moving around of the leads that was done during the mod. In fact, the wire connecting the output jack to the PCB came loose during the mod, so I was slightly concerned with other wires coming loose as well. Luckily that was the only one, so I'm hoping everything will hold up.

Overall, it just depends on your soldering skill. BTW, I recommend a mixture of desoldering braid along with a desoldering pump. I will use the pump first and then the braid if necessary...seems to make things easier IMHO.

I don't know if Boss customer support even exists, considering their reputation...it wouldn't make much sense to hire a customer support team that handles 1-2 calls / day!

As for Monte, I can't really say because I haven't had any problems. I will say that his instructions are thorough enough that there's really no need to contact him, unless you want to commend him on a job well done.

For $20 I don't think you'll find a better value. A compressor is something that usually doesn't "wow" you, and the original CS-3 certainly fit that mold. I can safely say that the CS-3 Opto mod has elevated this effect to the "wow" category. Thank you Monte, and keep up the good work. I can't wait to try out some of your other mods.

I agree with other reviewers, if you have some experience with a soldering iron and especially microelectronics, you will be fine. Even if not, Monte's instructions are good. Likely the trickiest thing for most will be correctly identifying the solder pads for some of the parts that get replaced. Tip - hold the circuit board up to a light, looking at the component side, and use a black felt tip marking pen, or some white-out on a fine brush tip, to put a dot on the back side underneath the holes that match the part to be replaced. it's not a disaster if you desolder the wrong pads, but you might find a non-replace part falling out and you'll have to put it back in correctly.

Great juicy goodness! The way Monte sets up the order of parts replacement, if you follow his wise advice of testing the box each time you replace a part, you will have a lot of fun hearing the cs3 open up and develop a tremendously improved sound. The first part to be replaced will make you go, woah! Same with each of the next few. Eventually each additional replacement will make more subtle improvements. I have a nice dbx rack compressor, but wanted high quality compression on my pedalboard. This mod on the cs3 is definitely a good answer. It makes my strat sound like a million bucks (an extra million bucks ;-)) and it's very good on my other guitars as well. Sounds great clean, and it works super with either of my OD pedals (self-modded ts9 or digitech bad monkey - a great value that really doesn't need mods) and with either my tube amps (fuchs, rivera) or my solid state amps (don't laugh, crate powerblock and the remarkable, rare westbury 250). The is only a very slight white-noise hiss left after all is said and done, which is pretty common even in expensive compressors.

well that's going to be up to your skill with the soldering iron and general care in handling the unit! don't blame Monte!

everything i needed was in the pack or the complementary materials he gives you links to on the website.

Play surf, blues, danny gatton, some latin. Play out in a band regularly, still have a dayjob. The opto modded cs3 adds a really nice juicyness to most material. I usually leave it on, and just vary the sustain, attack and tone settings. I know my way around electronics, but let's be real here - by the time you figure out the mods, shop for the parts, etc. monte is a mile ahead of you. This mod is a tremendous value and the best part is you can just sit down and do the whole thing quickly, without having to think (much)... so you can get back to playing and enjoying it more than ever.

This a review of the "Opto" version of the CS-3 mod. As to ease of use, I'd say if you are a little bit comfortable with a soldering iron, you'll be fine. Take your time, check the pedal after each mod as Monte suggests, and double check the pictures.
I did have a little experience, as I built a kit from Mission Amps, but before that all I'd done was swap out a few pickups. I'd say if you can put in some pickups, you'll be golden. Even if you haven't, if you go slowly I think with a little soldering practice you won't have any problems. Monte's diagrams are very clear, and he has some excellent resourses for soldering basics on his web site.
I spent about two hours on this mod, going slow, checking the pedal after each mod. I've already done another of Monte's mods, and without trying to go faster it did just because of the practice on this one...

Here is where it gets good. If you own a CS-3, you have to do this mod. Stock the CS-3 (I've probably had mine for ten years) is noisy and tone sucking. If you are playing loud and don't care about the noise, it can be cool in front of overdrive pedals. If you are playing clean at low volume, it will steal your tone.
I can't get over how good this thing sounds. The pedal is now quiet, and very, very sweet sounding. You can still do the infinite sustain thing that this pedal does, but much more quietly. More importantly you can use this thing like you would use a high quality compressor. With all the settings around noon, it sweetens, fattens, tightens the tone without making you sound all squeezed up. The pedal still feels very dynamic, especially when you roll back the attack time.
If you put it in front of an overdrive pedal, you can still do the rock god thing by raising the sustain setting to about 3 o'clock and rolling the volume back to about 9:30.
What
This pedal rating goes to 11. Most ratings only go to 10. This one goes one more.

Absolutely would use without a back up. Have already. Depenablilty I suppose depends on the quality of your soldering. Take your time!

Monte is a great guy, very helpful and personable. He loves his job, and it shows in the care he has obviously taken in developing these mods. I was so taken by the CS-3, I've ordered four more kits from him!

I play fingerstyle both acoustically and electrically, a variety of styles. I'm playing a variety of guitars (80's Amercan Strat with Fralins, 70's 335 with stock pups, a custom Tele with Bardens) thru that Mission Tweed I built, been playing for over 30 years in all kinds of settings.
If this were lost or stolen, I'd do it all again in a heartbeat!
Also- It's fun!! It's not only the search for tone that's cool about Monte's pedal mods. They are a bargain, and who doesn't love that! Also, you are participating in the process, and even though it ain't brain surgery, it's very satisfying to do the work and have the results be so satisfying.
I've been playing with the CS-3 for about a week, and am still amazed at how good this pedal sounds, especially from where it started. I felt compelled to spread the good word on Monte's kit. It sounds like he doesn't really need the business, but he deserves it!

I used monte allums 'CS-3 OPTO' modification, which is a few dollars more expensive than his standard CS-3 mod. The instructions were good, but there was no instructions for adding the LED (which is optional so i didn't bother adding it in the end). If you dont solder the LED the correct way around it wont work/may blow. I'm giving a 7 out of 10 here, since monte allums didn't provide instructions on adding the LED correctly =[ The rest of the instructions are fantastic though.

What can I say, I really truly love this modified pedal. Here is why. With the Stock Boss CS-3, it is not very good, because it is noisy (hissy) and it without getting all technical, put simply it doesnt really do any good to your sound setup. But modifying the pedal with the monte allums OPTO mod cleans up the noise and makes things sound great. I use a Marshall JCM900 valve amplifier, and I always turn up the gain quite far for a distorted rock sound. What I didnt like about this amplifier was that the lead sound was good, but just nothing special. It was tame, and not very alive. I like something sounding fatter, hotter.. I want my amp to scream, not sing. So with the CS-3 OPTO mod this is exactly what I get, by turning up the 'Level' knob on the modded pedal to about 1 or 2'o'clock. It fattens my tone up, and just sounds truly amazing. One of the other reviewers mentions how the OPTO mod pushes his tone 'hotter' (more output) and he says he doesnt like it, but for someone like me who actually wants a hotter fatter tone, the OPTO modded CS-3 is PERFECT! So to summarise, it takes my existing Marshall valve tone, but then pushes it further so i get a much fatter hotter sound now, without having to hit my guitar strings with violent force like angus young of ac/dc had to do in the late seventies in order to get his screaming lead sound! if you dont want the CS-3 to affect your 'tone' and be transparent, just dont turn up the knobs too high, but if you want to push things further, basically the option is there, just crank up that 'Level' knob..

If you modify the Boss pedal carefully and correctly, expect it to last a long time. Boss are reliable.

I emailed monte allums with questions and he replied fast with helpful answers. I can't complain.

Such an incredible pedal now with the monte allums CS-3 OPTO modification. I have owned various pedals in the past but always sold them. I'm keeping this one though and the reason is, I now get to use my great Marshall distortion sound, but now can push it a little further and get an edge on everyone else. Makes you feel special =]

Since the monto allums modification is so cheap, and transforms the pedal into 'god' territory, im giving full marks.