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Discussion Starter #1 (Edited)
I don't want to go down the deep rabbit hole of building pedals from scratch (or kits), but I'm wondering about the more shallow rabbit hole of modding basic and inexpensive pedals.

I want something to do as a hobby in the area of electronics that is inexpensive, safe, challenging and related to my interest in playing the guitar. I have a dedicated electronics work area and my soldering and schematic reading skills are reasonable. My knowledge of electronics theory/circuit design/nodes/etc is limited but slowly growing.

Any comments/advice?

There is a Boss DS-1 locally on Kijiji for $40.00 and thought that might be a fun starting point.


Thanks

Cheers

Dave
 

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IMHO, building from scratch is easier (assuming simpler projects vs the more involved ones; basic fuzzes and filters for example; even some distortions or overdrives). It will also help you build the skills for going at modding. Unless you're really good at (de)soldering, and have a good iron and pump (or even a proper desoldering iron) then you can very easily ruin the PCB. Modern stuff is a bit more robust but older pedals have PCBs with much more delicate traces and if you've never done it before it can be a real pain to remove components (especially ones with more than 2 legs) and you'll end up lifting traces. The worst is vintage single sided stuff where it feels like tin foil glued to the phenolic; lifted a few traces in my Orban compressor years back because of that. Most of the time you can just replace the trace with a jumper, but sometimes it gets complicated (especially with double-sided PCBs ).

Practice on a kit or 3 first. ...though I guess DS-1s are hardly rare and $40 isn't that big a risk.
 
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Discussion Starter #4
IMHO, building from scratch is easier (assuming simpler projects vs the more involved ones; basic fuzzes and filters for example; even some distortions or overdrives). It will also help you build the skills for going at modding...................
Thanks for your advice! Much appreciated.

I certainly respect your knowledge and experience.
 

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Discussion Starter #6
If you choose one you'd like to try, I can post details:

3] fizz kill
Welcome to the forum and thanks for your response.

I haven't actually purchased the DS-1 yet, but I'm curious to see what is involved with any of these mods...so I chose #3

Thanks

Dave
 

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Welcome to the forum and thanks for your response.

I haven't actually purchased the DS-1 yet, but I'm curious to see what is involved with any of these mods...so I chose #3

Thanks

Dave
OK.
There are a few places to tackle fizz in the DS-1.

a] a 1nF cap across the Distortion pot gives a progressive rolloff as the drive is increased.
b] an extra 2-3nf across C10
c] 15nf across the Tone control pin 1-2
d] 18nf across R21 near the output

I've used all of them together with success, but you can try a mix & match as well.
 

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Having dealt with untold hundreds of queries about modding over at the DIYstompbox forum over the past 20 years, one of the more common mistakes is to try to turn one pedal into something else. That is generally reflective of a lack of understanding about what "makes" a given effect what it is. It's akin to someone asking "How can I turn my toaster into a microwave oven?". That's certainly not what Dave is asking, but it's a common enough phenomenon that I had to mention it.

A second phenomenon is something that I called the B.U.M. syndrome - blind urge to mod. I can't begin tocount the number of posts that begin "Ijust got a <insert pedal name here>. What are some cool mods I can do?". Stompboxes tend to fall into 2 broad categories: those where the manufacturer has developed something intended to work well and please all potential users, and those where the manufacturer has takena proven design and changed something about it to suit a niche market. That certainly doesn't mean mods are moot or to be avoided. It does mean that one needs to have a sensible rationale for modding, and identified goals, before applying iron to PC board.
 

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I've been playing since 1973. In the 80's I got in to the mod phase that lasted in to the early 90's. I modded just about everything. It was a lot of fun but as the years went on I modded less and less and now I just buy exactly what I want. The 52 tele ri I just bought the only mod I do is swap out the saddles for compensated.
Pedals I never bothered much with modding. There is so many options I just don't see the point. But I understand those that do as modding can be a lot of fun.
 

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Discussion Starter #11 (Edited)
The pedal mentioned in my post was easy and fun to build and the documentation taught me a lot.
I did read your thread. Congrats!

I was just looking at the documentation. Excellent!!
upload_2018-1-12_21-1-13.png

What does what?
Fig. 3 explains the basics.

To get you up and running with minimum theorizing, these explanations are greatly simplified.

1. Guitar signal enters here. C1 acts as a filter. Smaller capacitors remove more lows.
2. The transistor amplifies your guitar signal—so much so that it distorts. Different transistors provide different amounts of gain.
3. The battery powers the transistor. R2 regulates the amount of current reaching the transistor.
4. R3 regulates the amount of current flowing from the transistor to ground. Lower values equal more gain.
5. R1 adds some current from the battery to the pre-transistor input signal.
6. C2 removes DC signal, preventing it from reaching your amp
 

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I may have created the false impression that I don't think pedals should be modded. In actuality, modding an existing pedal is a great first step to building, for the simple reason that you start off knowing everything works, and that whatever might go wrong thereafter is because of the specific thing/s you've done. When a novice tries to build an entire pedal, and somehow it doesn't work, or work right, where did things go wrong? Could be a thousand things. So, best to start with a sure thing. It's also a great way to learn what does what and how things work.

One of the nice things about modding is that "mods" can often consist of tacking a component here or there on the copper side of the board. The space between the back of the board and the chassis doesn't always permit adding parts, but sometimes they do. F'rinstance, lots of Tube Screamer-derived pedals use the same 4k7/.047uf combination to set the gain range and roll off the bass. Simply tacking a 0.1uf cap to the pads where the .047uf cap is installed, on the copper side of the board, adds new life to the pedal by restoring more bass. Some folks will make a big deal about cap type, but a plain vanilla ceramic disc cap will do the job admirably and fit nicely in the available space. And AFAIC, it's rock and roll. You don't need anything higher quality.

Other sorts of mods can be equally simple. For instance, say you have a phaser and you find the fastest speed just a tad slower than what you'd like. Find the resistor that sets maximum speed, identify the pads where that resistor is installed, do some simple math, and tack on a second resistor in parallel to reduce their combined resistance. The Boss PH-2 phaser uses a 250k rate pot, in series with a 2k2 fixed resistor to set maximum speed (the higher the resistance, the slower the sweep rate). If max speed is a little too slow, tack on a 10k resistor in parallel with the 2k2, dropping the effective combined resistance to 1k8, providing a slightly faster maximum speed.

And since a DS-1 is on the menu, let's try another one. The DS-1 uses a tonestack similar to a Big Muff. The signal gets split into two paths - lowpass and highpass - and the tone control simply pans between the two paths. The lowpass path rolls off lower mids and above, to help create a bit of a midscoop, using a 6k8 and 0.1uf pair. Lowering the valueof the 6k8 raises the frequency where the rolloff begins. Stock, it begins around 234hz. If we stick a 10k resistor in parallel with the existing 6k8, we end up with an effective resistance of 4k, and bump the rolloff up to just under 400hz, which gives us a little more definition and "vocal" sound in the full bass tone setting.

I mention these sorts of mods because nothing has to be removed to do them, and they are easily reversible. In contrast, removing components tends to require more heat and greater risk to the board. Moreover, one can simply solder one lead from the added component to the copper side, and briefly touch the other "free" lead to the corresponding pad, and listen to what it does. The instant A/B with/without comparison can be very helpful for determining IF it matters, and any fine tuning that may be required. Don't be afraid to use 1/8W resistors, and small ceramic disc caps.

There, I hope that's useful information.
 

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I just have to add my 2 cents worth on this one cause I know Dave never listens to what I say but I always say it anyways.

First of all.... 2 facts that I truly hope no one will dispute...
Fact one.... there are a hell of a lot of different pedals in the world these days...I actually stopped counting at 2 zillion.
Fact two.... I am going to assume that a lot of folks who do buy these pedals at some point or other will ask Mr. Google
to tell them all about the particular pedal they just got and sooner or later they will also come across some interesting mods that
make the pedal much better.
Here is something that I am certain of.....the VAST MAJORITY of these folks will never be able to make those mods.
Some will know their limitations and just think of the mod as an interesting idea. Others that think they can make the mod will inevitably ruin the pedal and basically just go out and buy another being much wiser.
For those 1 percent of 1 percent that can actually make those mods, good for you but you are not part of my point.

Speaking of making a point....well here it is...
IF anyone ( Dave included) wants to and can make mods to pedals, why not advertise to anyone who may want a specific mod to their existing pedal and for a reasonable price, make the mod for them.
kinda kills a lot of birds with just a couple of stones. Actually, I like birds so that was uncalled for.

cheers
G.
 

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Discussion Starter #15
I just have to add my 2 cents worth on this one cause I know Dave never listens to what I say but I always say it anyways.
I listen to what you say...I just don't always totally 'agree'. We just move forward after 'agreeing to disagree'...Correct?

ask Mr. Google
Mrs. Greco wants to clarify that if anyone wants to humanize "Google",
"Ms. Google" is the correct term.

IF anyone ( Dave included) wants to and can make mods to pedals, why not advertise to anyone who may want a specific mod to their existing pedal and for a reasonable price, make the mod for them.
Let me introduce you to Robert Keeley...

There are many, many others in this business, I just don't know their names.

This purpose of this thread is to ask others about their thoughts regarding modding pedals as a potential hobby for me. I fully expect that I will never develop the level of knowledge and skills to offer to do this for others to any real extent.
In addition, I do not want to start and develop another business of any sort...ever. Four business 'adventures' in one lifetime is enough.

Others that think they can make the mod will inevitably ruin the pedal
I fully understand that I will make mistakes and ruin some pedals. I know my electronics skills/knowledge are very limited. However, I view this as a way of learning more about electronics and circuits and having some fun with something associated with playing the guitar.

This thread now has me debating the options of:
...modifying an existing pedal
OR
...buying a kit from B.Y.O.C. in Brantford.

Thanks to everyone that has contributed to the thread. Much appreciated.

Cheers

Dave
 

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Discussion Starter #16
* Nevermind Greco I see you already posted in my post that I posted post haste.
Are you trying to scramble my brains on purpose?

You have been reading too much electronics theory recently and need to take a break!...LOL
 

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I did read your thread. Congrats!

I was just looking at the documentation. Excellent!!
View attachment 158929
What does what?
Fig. 3 explains the basics.

To get you up and running with minimum theorizing, these explanations are greatly simplified.

1. Guitar signal enters here. C1 acts as a filter. Smaller capacitors remove more lows.
2. The transistor amplifies your guitar signal—so much so that it distorts. Different transistors provide different amounts of gain.
3. The battery powers the transistor. R2 regulates the amount of current reaching the transistor.
4. R3 regulates the amount of current flowing from the transistor to ground. Lower values equal more gain.
5. R1 adds some current from the battery to the pre-transistor input signal.
6. C2 removes DC signal, preventing it from reaching your amp
This is exactly what I mean by starting out with a sinple kit or scratch build. You get an idea of how things work; at the very least you learn to break the circuit down into functional blocks (input, output, gain, filters etc) so you learn something and can then make more meaningful mods. Just modding, adding a cap here or there cuz somone said, teaches you little and so you're just following other peoples instructions. At best you are, for example, as mentioned by @mhammer , changing a cap value (vs the instructions) to filter more/less bass out. Going back to the circuit above, once you've built it (or rather, breadboarded it - I would recomend learning that first - no soldering required and it allows you to make component or even circuit changes easily) you can play with it.

For example, the 2 obvious 'mods' to the above circuit would be seeing what adding a clipping diode(s) to the NFB would do (more or different dirt; try different diodes, what do they do, why; ah forward voltage what's that and how is it related to clipping threshold?) and adding an output volume (that transistor can raise the signal level quite a bit; the clipping diode may take that back a bit). That's education; when you figure it out yourself vs having someone tell you. Sure, you would look at other circuits, to figure out how/where to do it, but then you bring it back to this one to implement. Both very simple, and the process of looking at the schem of a similarly simple dirt pedal and applying those changes to this one will make a world of difference to your understanding and confidence.The argument that you won't be able to build this basic circuit so start with a working pedal is flawed in the sense that, maybe if you can't handle this (not saying first try - there usually is some troubleshooting involved when you build something; that's an important learning experience as well - and thats why you start simple) then you should not be messing with a working pedal (far more complicated with no hope of you actually understanding the circuit, or tracing it even). At that point sure, just simple well documented, non-destructive mods for you and forget the learning cuz you (the proverbial you, not anyone here specifically) have no aptitude (or alternatively, desire to see things through, which is fair enough). And that's fine too, if it's all you're into.

That's in addition to soldering and other practical skills you will hone or at least refresh before you touch that working pedal that is actually worth something.

As much as I respect @mhammer, I do disagree with him on this - yes modding can learn ya, sure, but only once you have more foundation, which modding does not provide, and there are too many 'shortcuts' to avoid any real learning (the vocab does not count).

That said, it doesn't hurt to start with a quick easy (nondestructive) mod to get your confidence up with a quick win. Those DS-1 mods listed above especially (adding a cap across a pot is pie and the DS-1, as mentioned, is cheap and ubiquitous).
 
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If I'm not mistaken, Analogman Mike Piera also started out doing mods. At some point, once I've finished all the backlog of projects I have piled up, I may offer mods. But I'll keep it local since I can't be bothered shipping anything. In many instances, it's also more satisfying to me personally to do the mod in front of the person, ask them whether it does what they want, and tailor if needed.

As for a GE-7 pedal, it's not impossible, but that's a pretty crowded board, wanting a fine soldering tip.

Many older pedals are predicated on conserving battery juice, so they will often sacrifice noise specs for power consumption. As more and more pedalboards use power bricks to supply all pedals, especially with those mini-pedals that have no battery capability to speak of, chip choices are changing. But older GE-7 gutshots show use of op-amps that sacrifice hiss for longer battery life, and those may be worth changing. If a "pedalboard" consists only of a wah and fuzz, that's not an issue, but with so many pedalboards and desired tones consisting of 5+ cascaded pedals, the cumulative hiss can be problematic and worth tackling head on....assuming it is imnprovable.

Still, some folks can go overboard in pursuit of supposedly ideal mods. Is it worth replacing a 4558 chip with something else? In my view, not often. It isn't one of those trade-hiss-for-power chips, so there aren't many applications where swapping it with a $3 Burr-Brown chip does anything useful. And while I will not cast any aspersions on the sincere intent and honest business practices of those who do offer mod services, when one has spent $60+ to send away an $80 pedal for modding and finally gets it back after 5-6 weeks, just about anything the modder may have done is greeted as a significant improvement by the pedal-owner, simply because they miss the damn thing and have so much skin in the game. That's not to say nothing was changed or improved, but the improvement may be much less than a more disinterested party might have noticed, if they were able to make the sonic comparison 10 minutes apart.

Incidentally, sometimes crappier components yield improvements. A local fellow, and former forum member (or maybe he's still around, just silent) brought his Timmy pedal over for modding, because he had read about another chip improving the sound. I unsoldered the JRC4558 chip that was in there, installed a socket, and we spent a big chunk of the evening trying out what must have been a half dozen or more different dual op-amp chips of different classes/categories. When all was said and done, the ultra-cheap pre-modern-era LM1458 was the winner, as relayed in whatever he had read. It was the shortcomings of that chip that shaved off some of the annoying high top-end and made for a more pleasing tone. I had been sceptical at first, but he was intent on making the mod, so I figured I'd go through the motions, and eventually come back to where we started. But I learned something that evening.

If one IS interested in modding, THE place to go is the DIYstompbox forum, where you will encounter an immense community of well-informed people who are extremely generous with their knowledge.

And, as for whether "modding can learn ya", my own approach is to understand the circuit/pedal first, and make any mods based on that understanding, not blind circuit-bending. (That is, after all, the basis for identifying the BUM syndrome.) In experimental research, one designs a study in order to hold certain factors constant, such that the impact of specific identifiable factors can be isolated. Modding can be, and should be, similar to that: here is what the pedal does in its natural state, here is the single thing I changed, and here is what it did. In other words, rational and methodical. If THAT doesn't provide a learning opportunity, I don't know what will.

If one has been to my home, you'll see several shelves of binders, containing thousands of schematics. My primary reason for owning a tablet, is so that I can carry about 8 gig of schematics around with me for consultation. It is largely by comparing different designs that stem from the same base, that one can think "Ah, I see what they did there" and come up with useful alternatives or extensions. So yeah, listen to your granny: understand first, and then mod.
 
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