What’s your favorite guitar mod? The kind that changes how you play. One you’ve become so accustomed to that you wince when you pick up an axe that lacks it?
I’ll choose pickup wiring mods as a starting point: During the year that Seymour Duncan sponsored tonefiend.com, I devoted many posts to the under-appreciated wiring schemes I found in the company’s wiring diagram database. Some faves:
- “Vintage” Les Paul wiring
- “Broadcaster blend” Tele wiring
- “Nashville-style” Tele wiring in both Teles and Strats
…and of course, the suicidal soldering mission known as the Pagey Project.
I’ve still got the “advanced” version of the Pagey wiring in my nothing-special beater Les Paul, and I like it so much, I want to fix up the guitar so it feels as nice as it sounds.
But of all the wiring experiments I tried, my absolute favorite is one that doesn’t appear in the Duncan archives: the so-called “PTB” tone control (for “passive treble and bass”). It’s a cliché to call a neglected idea “ahead of its time,” but in this case, it happens to be true. Being able to roll off lows as well as highs is unbelievably useful when sculpting sounds. It makes me want to run into the nearest Bain Capital Guitar Center, grab players by the collar, and shout, “You need to know about this!” (But I probably won’t, ’cause G.C. customers aren’t accustomed to receiving that sort of personal attention, and I wouldn’t want to freak them out.)
Allow me to repost last year’s video, demonstrating the circuit in action:
Over a year later, I remain totally addicted to this circuit, and I recommend it to anyone who doesn’t require a guitar with independent volume controls per pickup. (Everyone, basically.) It seems especially relevant for drop-tuned and 7-string metal players who realize you must sometimes cut a little bass to keep the lowest register tight and articulate. And the circuit is a godsend when used with bass-heavy fuzz pedals (such as vintage-style Fuzz Faces). In fact, I’ve even been building the circuit into the front end of certain loud fuzz pedals for use with guitars lacking this magnificent mod.
But I remembered something interesting this week when I opened up the Hamer 20th Anniversary guitar used in the video:
I cheated! I didn’t have the requisite “C-type” reverse-log 1M pot needed for the bass control, so I substituted a “B-type” linear 500K pot, the same part used for standard Les Paul tone controls. You don’t need to know much about electronics to suspect that changing the part alters the range and response of the control. But as you can hear, it still performs well.
This time, I replaced the B500K with a C1M. For years, reverse-log pots were practically unobtainable, though that’s no longer true thanks to vendors such as Mammoth. But as you can see in my incriminating control cavity pic, I had to use a small format, 16mm pot rather than a proper 24mm one, and the shaft is barely long enough to attach securely. (I’m not even sure if you can get a 24mm reverse-log 1M pot — anyone?) I would have made a new video, but the fact is, it doesn’t sound terrible different — it’s more of a feel thing.
With the proper reverse-log pot, the bass frequencies taper off more gradually as you roll back the pot. With the B500K, the action is more jerky and less musical. But since I happen to be somewhat jerky and unmusical, I may well go back to the substitute value as heard in the video above. The point is, don’t let the hard-to-find part derail you. This mod works great with a common B500K pot.
The schematic — originally provided by reader JH — and my wiring diagram appear here. One important detail: If you wire a guitar exactly as I’ve diagramed, the bass pot will siphon off bass as you rotate it clockwise, with maximum bass in the full counter-clockwise position. (The treble control, as usual, transmits maximum treble in the fully clockwise position.) If you’d like to have maximum bass with the pot fully clockwise, swap the connections between the outermost lugs of the bass pot. Actually, you can do that anytime a pot’s motion is the opposite of what you want — just swap the connection between lug 1 and lug 3.
Anyway, that’s my favorite guitar mod, the one I can’t believe isn’t more widely known and used. So how about you? What’s your favorite mod? It doesn’t have to wiring — it can be hardware, setup, whatever. Just hurry up and post it to comments before I run screaming through Guitar Center.
I’ve been playing a frankentele Cabronita with Powertrons for the last six months and giving my trusty 335 a break from the all sweat, sturm and drang. I had it wired so I get an out-of-phase setting as well as the bridge/neck p/u. I love this…in a two guitar band it gives me a sonic footprint waaayy different from the other guys. It gives a humbucker equipped guitar a pseudo-single-coil setting. I think my 335 will get it’s first mod soon…
That’s a great point — that “plonky” out of phase sound is a great way to find a niche in a crowded arrangement!
As the owner of a G&L Legacy, I am quite fond of the stock PTB system in my guitar, especially since I installed a moderately hot humbucker in the bridge position.
Another mod I really like (though I don’t have it on any of my guitars) is a phase switch, especially on guitars with Gibson-like wiring (2 volume, 2 tone). With a little tweaking of the controls for each pickup, you can get some neat variations. One of these days, I’d like to try it with Fender TBX controls on each pickup, mostly because I can’t leave well enough alone. 🙂
The mod I do have that I like is the S1 switch on my Telecaster, which switches the pickups from series to parallel. It’s very useful – the series position is powerful, but clear.
I’ve never tried the TBX circuit. Though I found this article on how it works: https://www.premierguitar.com/articles/The_Fender_TBX_Tone_Control_Part_1
You can buy the necessary stacked pot online for under $15. I just ordered a couple — thanks for the idea! I’ll let you know how it goes.
Gave a TBX I had laying around to a friend ,he put it into his Stellacaster and swears by it now. It does sound really good with the SD everything axe set in it and all the options.
Hey Joe,
I couldn’t agree more with you, I have my Strat modded with PTB and a Switch to toggle all three pickups / Bridge+Neck, just like G&L guitars; and it just makes my Strat perfect.
But contrary to your schematic, I used a Cap/resistor filter and it works wonderful.
I want to ask you something; does it makes any difference using 24mm and 16mm pots?
I’ve been DYING to try out the PTB on a Fender. My cheapo Mexican Strat is in pieces in a cardboard box, but I think I’m going to reassemble it with a PTB. Do you think it would sound good with lipstick tubes?
I’m gonna guess that if you do lipsticks with the usual five-way switch setup that the bass knob will have limited utility. The reason I say that is Noise at ilovefuzz put a couple of EY Guitar lipsticks in his Jaguar and said the strangle switch was practically useless. https://ilovefuzz.com/viewtopic.php?f=192&t=35897&sid=32b2b49fcaf2c9d15ad51ce1e5fe8746
But, let’s say you wanted to use the Dan Armstrong super Strat wiring https://www.dominocs.com/AshBassGuitar/index.html?armstrongstrat.html that has some series options that will probably up the bass and low-end grunt. The bass knob might be more useful, then. I’ve been contemplating this setup for a while for a Fernandes Strat that has potential but some junky bits. I’ll try PTB and if that fails a varitone.
(The other upgrade I have in mind for the Fernandes is replacing the six-screw trem, which is a basket-case, with the Wilkinson WVS-50IIK, the import-spaced cheapie version of the two-point trem you put on your black Strat, Joe. So I wanted to ask — did you just use the stock screw holes as pilots for the trem bushing holes, or is it more complicated than that?)
You should; I really love Lipstick tubes, especially when you play it, as in your Demo. What do you think about Hot Rails in a Strat?
Hmmmm…the mods I like the most are mostly Tele mods, since I mostly play Teles. Barely qyalifies as a mod, but I really like a nice set of compensated saddles, especially Rutters. I also have one Tele that I removed the side “lips” of the bridgeplate from and drilled for either/or string-through and toploader. Not a huge tonal difference, really, but a significant feel difference between the two schemes.
Recently rewired my Esquire with the “cocked wah” mod in place of the original dark circuit, which is nice. I liked the bassiness of the stock setting, but the volume drop associated with it? Not so much. Really digging the mod so far.
On my strat, I use a master volume/master tone/blend pot wiring scheme, so I can get a little (or a lot) of neck pickup mixed with the bridge pup. Or all 3 pickups at once in switch positions 2 and 4! Honestly, though, the best part is having a tone knob that actually feels like it DOES something in every position.
The BEST mod I have, by far, is this weird little cap attached to the sleeve of the output jack of a ’70s Musicmaster I’ve had since I was a youngster. When you’re not playing, you close it like a tube of toothpaste! No idea where it came from, it was there when I bought it.
Man, you guys are giving me lots of ideas! Is this the mod you mean? (See post #38):
https://www.tdpri.com/forum/telecaster-discussion-forum/316053-want-info-about-esquires-2.html
Think there’s a way to generate something similar on a two-pickup Tele?
Yep- that’s probably even the TDPRI thread I found the wiring diagram on. I like the “Eldred mod” enough that I’m now thinking about different cap values and maybe a four-way switch to emulate a wah cocked at different points along its sweep. Pretty sure doing something similar on a two-pickup guitar shouldn’t be TOO hard to figure out-and with a four way switch, you wouldn’t even have to lose the stock settings.
Other than disconcerting backwardness, why not use log instead of reverse log for the bass pot? It is the same but CW/CCW reversed, right?
Just put a four way switch on my hand built by me Tele. The neck / bridge in series is a great sound, plus I still have the standard three pickup selections.
Bear is right about the reverse log pot trick and I think it almost makes more sense to have the pot roll that way on a PTB set up. G&L used a passive bass control on some of their Strats, I have beautiful transparent forest green G&L with a bass control.
Many of the major pot manufacturers actually offer 6 different track tapers, at least in log pots. Both CTS and Alpha offer curves that provide 5%, 10%, 15%, 20%, 25% and 30% of the total track resistance at the half rotation point. Unfortunately it seems like many of these are only made to order and the distrbutors only carry one taper and usually don’t indicate what it is. I think I am right in saying that a true log would be the 10% curve.
CTS do not seem to offer an anti-log in their guitar series of pots.
Thanks Terry! Do you have any idea how cool it is to have a blog where I can blurt out something like, “Anyone know if they make 24mm C1M pots?” and someone knowledgable immediately replies? 🙂
Joe it is possible to sort of “roll your own” pot tapers. If you take a higher value pot and put resistors across the lugs between center and either end you will change the taper of the pot. I remember reading this in an old ARRL Ham radio handbook many years ago. The only thing in your case is that the starting pot needs to be a higher value than what you want to end up with IIRC. Here is a page that shows changing a linear to audio taper adding a resistor:
https://www.jt30.com/jt30page/potfix/
and another:
https://sound.westhost.com/pots.htm
But I would just like to find pots with long shafts for guitars that mount the pot thru the body (with dpdt switches).
Wow — do you have any idea how cool it is to have a blog where I can blurt out something like, “Anyone know whether they make a 24mm C1M pot?” and someone knowledgable answers immediately. Thanks, man!
mine is simple and has been around a long time now: on a strat, switching the middle pickup tone control to the bridge pickup. I gotta have it, for two reasons. one is the obvious, to tame the high end of the treble pickup; but the other is just as important – no tone on the middle pickup allows you to lower it way down, almost flush with the pick guard, and still be in volume balance with the other two pickups. Solves the chronic problem, for me anyway, of the pick constantly banging against the pickup. it actually sounds good too. it’s amazing how much more gain pickups have when they don’t run through a tone control.
I did the PTB and several other mods in a strat. It’s a really heavy (9.5lbs) Asian strat from the late 70s that has these pickups that are larger and more powerful than normal strat pickups. I swapped out the middle pickup for a standard strat-sized lipstick tube pickup as well, which is a bit lower output. I added individual pickup switches and a killswitch as well. But the PTB is what really makes it special. I went for the normal strat setup where the bridge pickup isn’t involved in the tone controls, but through a wiring error I can’t understand, it’s still affected by the treble cut, but not the bass cut. This is a happy accident though. What this allows is for significantly improved tones when blending pickups. In normal strats with mods that allow for all pickups being used at once, people complain about the sound of all 3 at once not being useable. However, I can cut the bass for the neck and middle pickups only, making the bridge pickup much more prominent in the mix than the others, which gives a really bright sound like the bridge alone, yet it’s also more full because the other pickups are present too. And I can get a similar effect by keeping the bass up and cutting the treble, so it more sounds like the neck pickup alone with some additional brightness.
It sounds great, and I’m not even done with it yet. Once I get the money, I’ll probably swap out the bridge pickup for something that’s more of a cross between a telecaster and strat sound. And I want to get the stock neck pickup wax potted to reduce the microphonics/feedback too. And after reading this blog, I think I might also stop “cheating” and use some pots that aren’t standard 500k… All in all, it’s the best mod I’ve ever heard of, and I’m rather adventurous when it comes to electronics mods.
Sounds really cool. Don’t suppose you have any audio clips?
I don’t unfortunately, but I might look into making some soon.
My favorite mod is a very simple one. I found it in “Guitar”, a British guitar magazine I’m not sure still exists, in 1992 (I don’t have the mag anymore). If I remember well, the idea for this mod was by Brinsley Schwarz, English guitarist.
Anyway, it consists in, when you shunt a humbucker to single coil mode, instead of completely shorting one of the coils, you put a capacitor across it. 10K is very useable, but you can experiment, of course.
This way, you get one coil AND the lows of the other; depending on the value of the cap, which cuts the highs, of course. To me, it sounds, when you find the right cap, and with the right humbucker, way better than just a coil from a humbucker.
Anyone has heard of this mod? Because 20 years have passed and I’ve never seen it again.
When I say “the right cap” I’m meaning, of course, “the right cap value”. Being an electronics engineer, I would be the last to believe in capacitors mystique.
OK, a bit of googling, and I found something: https://www.kvraudio.com/forum/printview.php?t=324336&start=0
Brinsley Schwarz, I was right.
Oh man — now THAT is a list of links worth bookmarking! Thanks!
It’s already been mentioned but I love the 4 way mod on my tele. Sounds great and keeps the original 3 sounds. In series it’s thick like a humbucker but maintains the expressiveness of a single coil. Love it!
Yeah, that’s one of those great “nothing lost” mods — you still have all the original sounds, plus that honking loud series settings.
Have to say when I buy a guitar the first thing I do is remove the paint from the neck and sand to 1000 or 1200 grit and Tung Oil it. Would probably do it to a 59 LP if I had one too.I am kind of attached to the hardware I put on guitars now , for the bridges I replace with a Babicz FCH ( Tele, LP. 335) , Planet Waves Trim Lok Tuners (love the no pointy string bites every again part) zero wraps on a peg is a wonderful thing for tuning and so is 18:1 ratio.Partial to Graphtech Tusq XL nuts and saddles synthetic stability. The Greasebucket Mod on my Tele is nice gives a full range of response for the entire track. I have series/split/parallel toggles and Blend Knobs on my HM Strat and Jackson RR (Anderson pups) wide range of great tones in both of them (I love my middle pup on my Strat too !) Duncan Straplocks on all my guitars also. We will see if the next 2 builds (335 and Explorer) get the entire Pagey Project and PTB both are on my list of things to do (6 way Page switch too) What else can I add to this babble guys ? Oh Freddie got to be 100% with you on the “right cap value” !!!!! I know this moron (story to be never told) and the guy tells me he can tell difference between cap types by ear ! Worst part about it the guy is an amp/pickup guitar repair guy. I guess he does not understand when something is beyond the range of the human ear to discern? :pity: Kills me
Yes, everybody wants to be Eric Johnson these days.
+1.
I’ve said it a thousand times, and I’ll say it again: the material of passive components doesn’t matter in guitars and stompboxes. Those oil-and-paper caps and big carbon resistors may fill you with pride when you open the control cavity, but they are sonically indistinguishable from smaller modern components.
Component values, on the other hand, are very important.
And that’s all there is to it.
I love intelligent human beings !
Tho’ I largely agree with you that there is no “mojo” in old components especially carbon comp resistors I have seen evidence that there are some differences. Back in the early 80’s I worked for August Systems in a small town near Champaign called Sidney, Illinois. We built, sold, repaired and modded esoteric hifi equipment as well as pro-audio. When we were designing passive x-overs for home loudspeakers we did all kinds of double blind tests using the local townies and the farmers from the area, literally pulling them off the street into the show room and had them listen to A-B tests where we changed a single component in the crossover. We found that even untrained ears could give us good data and in this particular case we found that some electrolytic caps from Aero corp. (a french company) were better in all listening tests whether it was an old farmer or a hifi geek. These caps were polar type caps so we used them in a back to back pair in all our passive x-overs to get the non-polar caps we needed. We used these caps in audio paths both of passive x-overs and audio circuits for years until we ran out ( I wish I still had some to try in a fuzz circuit but I used the last ones I had nearly 20 years ago).
Some tests were done as well on resistor type and we found that good wire wound resistors sounded best followed by metal film and carbon film and carbon comps were big losers. The main thing people heard was a cold, fuzzy, noisiness of carbon comps while carbon films and metal films were considered OK, the wire wounds had some people talking about focus or clearness of the sound. We only did these tests at room temps and probably should have simulated higher operating temps.
We found people were way more critical of noise, hum and static than any measurable distortion in fact we found that loud freaks love harmonic distortion. We used this in our dual action limiter for power amps for frat house audio systems, where after a certain point the volume control just added harmonic distortion but no more volume. People loved those “party speaker systems” and they sounded good but never blew up.
None of the above tests used anything but ears as test equipment (tho’ we had well equipped test benches) but we had long since realized that volt and amp measurements didn’t reveal what our ears heard so easily.
All that being said we were using all new parts at the time (the term NOS had not been invented yet) and everything we tested was of current manufacture for the time (early 80’s),
For the record I have a big grudge against carbon comp resistors being good for guitar amps, IMHO they are noisy, nasty, usually out of spec and should be replaced with metal films or non-inductive wire wound resistors whenever they are found. I have rebuilt amps with wire wounds replacing carbon comps and never had anything but raves from the owners and users. YMMV
Dude!
Great topic. Just a quick comment to say that your “Broadcaster blend” link actually links to the “vintage” les paul wiring page.
P.S. My favorite “mod” is to take a 70’s Tele that noone wants (or at least they didn’t in the past) and drop some 250kOhm pots inside (replacing the 1MOhm ones) and suddenly you have a rock-monster. Oh-well, now that 60’s instruments have gone through the roof even the heavy 70’s guitars are too expensive as well.. But it worked for at while.
Thanks, Lars — I just fixed the link. Yeah, those ’70s Fenders aren’t quite as easy to come by as they used to be, huh? But if it’s any consolation, the cheapest new Fenders have gotten so good and consistent that it’s pretty easy to turn them into non-vintage rock monsters. 🙂
I’ve been on the fence about doing this to my ’76 Tele for a while now. I’m not exactly attached so much to the sound of the 1M pots (nor the treble bleed cap across the volume pot), but I LOVE the taper of those pots and the sweep of the tone control. Plus, they turn reeeally easily, which rules for manual wah and tremolo. On top of that, I have an old Gibson humbucker in the neck slot, and I’m kinda worried it might get too muddy with 250k pots. As is, I could do with a tad more bridge pickup beef, but the neck pickup is just right.
…and I’m with Joe- I have 2 moderately priced MIM Fenders, an Esquire and a Baja Tele (bith modded, of course), and while I wouldn’t say either is quite as good (or heavy) as the ’76, they are as good fit and finish-wise, and sound fine.
I agree completely. I just had a period in my life (well to be honest I’m still struggling) where I wanted the oldest, most vintage guitar that I possibly could get hold off. The thinking was that that exact sound and feel of the vintage guitar would somehow lift my mediocre playing and elevate me towards becoming a “real” guitarist. But now, because I love to tinker, I find a more interesting challenge in finding the best sound in the cheapest instrument. So, close to same sound, but 5% of the cost (but, obviously, sacrificing the feel of the vintage instrument)…
My most common mod to my guitars (besides replacing crappy pots with better ones) is to replace the stop tailpiece with a fine tuner stop tail piece ( Schaller and Gibson both make them and maybe TonePros but theirs looks like the Schaller in pics). The tuning accuracy gained is worth the effort and $$$ and it usually increases sustain a bit due to the weight increase. Besides that I have been putting Stellartone Tonestyler controls in place of tone controls in my single volume/ single tone control guitars. I may be an exception to Joe’s mostly true comment of most guitarists don’t need to 2 vol/2 tone setup. I really love the variety of tones available with small changes to individual volume and tone setting with both pickups engaged in 2 vol/2 tone setup, particularly for recording. I also usually spend time fixing the grounding scheme in the control cavity of guitars adding copper foil where it is needed but also establishing one central star ground (usually near the output jack) and rewiring the grounds to a star ground as much as is reasonable to do so. IMHO running the control cavity grounds on the pot housings (which is sort of a de facto standard for electric guitars) is a real recipe for noise injection in to the raw guitar signal,this is particularly a problem for playing out live at small clubs.
After reading about it here last year, I put the PTB in a kind of woofy sounding strat. And I love it. Thank you very much. Since I use only two knobs, master vol and master tone (I remove the first knob by the strings because its in my way -> another useful mod) the PTB is on a stacked concentric pot.
I know Joe doesn’t care for mismatched pickups in the same guitar, but I’m a big fan of having the middle pickup in a strat be much lower gain than the outer pickups. Does that count as a favorite mod? Or refretting with medium large stainless steel frets (not something I actually do myself).
Best thing I ever did to my Les Paul was a refret with Stainless Steel and it is on the list of things to do for all my guitars. Trying to start them off with S.S now, saves time and money.Best part about it is that my fret guy put the extra wide Gibson type wire without cutting the top off it and making it flat , the way it was done originally.(never got that idea but action was extremely low)
My favorite mod for some time now, and I believe a few people have alluded to it already, is to tap a humbucker through a capacitor. A typical coil tap on a humbucker makes for a weak and thin single coil. Shunting the tap to ground via a .1uF cap retains the low end and most of the volume of the pickup, but puts a nice scoop in the mids. I use this in conjunction with the bass control mentioned earlier to get nice single coil style clean tones from my humbucker-laden axes.
Does anybody find it weird that on effects pedals with output volume controls the control goes from zero output (why would you ever want zero output from an effect? ) and often achieves a balance between active and bypass at around 3 o’clock?
It seems to me it could be worth inserting a resistor between signal ground and the counter clockwise end of such controls to bring the balance point nearer to the mid position of the control.
Terry that is very insightful. The pedal “volume to zero” feature was requested by the other members of the band. :oogle:
Adding a Bigsby (I’m easily amused)!
Joe, is your cabinet a 112 with a Celestion Blue? I love the sound. Is it a newer celestion or a vintage one? open or sealed cab? thanks
Hey Joe! I really wanted to give this mod a go in my LP and I did. I had to modify it slightly of course to cater for the 4 Knobs as opposed to the 3 Knobs in your schematic. Managed to get everything working and the Bass control knob does do something but its not as dramatic as in your video. Curiously it seems to add some hum as I bring in more base and becomes dead quiet when the bass is rolled off. I was wondering if you’d take a look at my schematic and tell me if I got it right or I’ve messed up somewhere? Here is the link –
https://docs.google.com/file/d/0BxUhAKL2WrZYWm05SXB1QUNoQ0U/edit.
Many thanks!
Btw you should really add an RSS feed for us DIY junkies – would love to keep more up to date with what you got going on here. Love it :beer: !
Hey Joe! I really wanted to give this mod a go in my LP and I did. I had to modify it slightly of course to cater for the 4 Knobs as opposed to the 3 Knobs in your schematic. Managed to get everything working and the Bass control knob does do something but its not as dramatic as in your video. Curiously it seems to add some hum as I bring in more base and becomes dead quiet when the bass is rolled off. I was wondering if you'd take a look at my schematic and tell me if I got it right or I've messed up somewhere? Here is the link – https://docs.google.com/file/d/0BxUhAKL2WrZYWm05SXB1QUNoQ0U/edit. Many thanks!
Figured it out! Here is the corrected circuit diagram:
https://docs.google.com/file/d/0BxUhAKL2WrZYVWNrZjY5WWFxS3c/edit
Look forward to living with this mod for a while and seeing if its a keeper! Cheers.
I’m not a big solderer/tinkerer except in emergencies (hot-knifing a borrowed bass together in the Bahamas, for example) but my Strat has a twist I’ve become so used to that other ones seem weird. It’s a ’71, which I picked up in ’85 or so, already well scuffed up, & when I took it for a set-up my luthier discovered that the bridge p/u was a double-coil, double-deckered so it looked entirely normal from the outside. He suggested taking out one of the tone pots & replacing it w. a coil-tap switch: seeing as I’m a big lover of the in-between/p/u Strat sounds, I said “sure, but switch the double to the middle!” Thus for the last nearly 30 years I’ve had 8 rather than 5 p/u combos, and am obviously totally used to it. The switch is useful as a rhythm->solo boost, & also to adapt to different room sounds on any given night.