Greetings from the Lace Pickups team!

[David Schwab]

Nothing wrong with using a hammer to seat frets. I've been using the same 8 oz stanley hammer for 30 years, broke the shaft 20 years ago and glued it back with titebond and it's still holding strong. It's horses for courses. It's nice to be able to but some tactile feeling into fretting a guitar. I suppose if I was making 10 guitars a day I would press them in, or maybe not, or I could always get a cnc machine to put them in. But then it kind of defeats the object of being a guitar maker and making something by hand the old fashioned way. Each guitar player plays differently and has a different feeling lets hope that stays that way. Just my thrupence worth.

Cheers

Andrew

I hammed frets for the past 35 years too, but pressing them in works much better, and you generally get them to seat better. My opinion is to keep water based glue away from the fingerboard. I use CA when I need to glue frets in, and epoxy to glue fingerboards on.

You get lot of tactile feedback from pressing. More so than when hammering. It's not any faster, but it applies more uniform pressure to the entire width of the fret. If you are gluing the frets, you can hold the press down as a clamp.

I have to do far less leveling of the frets when pressing them in than when I hammered them in.

[Hugh Evans]

Aside from pressing frets in there is one other technique I picked up from a guy who had been in the repair department at Martin for 30+ years: get a cobbler's hammer. Since they are not exceptionally heavy, and have more surface area on the striking face, by using nothing more than the weight of the hammer it will seat the frets perfectly. The other half of this procedure is to rest the neck over your legs while installing the frets (shock absorber.) Provided the fretboard is level, the frets will be as well.

[salvarsan]

I have to do far less leveling of the frets when pressing them in than when I hammered them in.

Melvyn Hiscock, author of Make Your Own Electric Guitar, once complained of the noise from hammering.
I wonder if it was because of a steel hammer instead of brass (which is softer).

[MR COFFEE]

Lex,
A question on the Alumitone design...

They read over 5K ohm resistance on my ohmmeter, and I just can't believe that is all wire turns resistance, no matter how thin the windings are. The coils are just too small to have that much resistance.

You put an RC (resistor-capacitor) filter on the output to kill RFI (radio frequency interference) up inside that shrink wrap over the C-core coils, right?

Maybe 5K and 820 pf or thereabouts?

I am all for y'all working on the double transformer idea that Joe advocates for - I think the can of worms is just squirming to get out!!

And welcome to the forum!

mr coffee

[David Schwab]

Melvyn Hiscock, author of Make Your Own Electric Guitar, once complained of the noise from hammering.
I wonder if it was because of a steel hammer instead of brass (which is softer).

I have one of those hammers with a brass and nylon head. I also have a small ball peen hammer that I ground the ball into a chisel. I use that when you need to make the tangs wider for lose fret slots.

Lately I've been using one of the Stew-mac fret pressing systems I bought back in the 90s. I have an arbor press set up for it, but that's not at my home shop, so I have been using a bench top drill press. I like pressing because if you have bent you wire to a slightly larger radius, it seats nicely and you don't have to tap the ends down. With the hammer you sometimes get a little recoil.

[David King]

I see Matthew is involved with Frank's guitars. I like that!

[kayakerca]

I hammed frets for the past 35 years too, but pressing them in works much better, and you generally get them to seat better. My opinion is to keep water based glue away from the fingerboard. I use CA when I need to glue frets in, and epoxy to glue fingerboards on.

You get lot of tactile feedback from pressing. More so than when hammering. It's not any faster, but it applies more uniform pressure to the entire width of the fret. If you are gluing the frets, you can hold the press down as a clamp.

I have to do far less leveling of the frets when pressing them in than when I hammered them in.

Couldn't agree more on pressing frets in. I only do refrets but find the Stewmac Jaws vicegrip style press works great. I fret on a neck jig I built based on the Stewmac model. I like to over raduis the fretwire so the ends seat in nice, then clamp them down with a caul the raduis of the neck until the glue cures. I do use hide glue for ease of use and cleanup. Still hammer in the last few frets around the body as that though as that clamp doesn't work in that area. Even though the neck jig is rock solid when the guitar is strapped in, I really don't like hammering on those first dozen or so frets on a guitar in my neck jig that are accessible with the press.

[David Schwab]

I do use hide glue for ease of use and cleanup.

I wouldn't say hide glue has ease of use! I don't use hide glue at all for anything. I used to use titebond for frets, but now I use CA.

Still hammer in the last few frets around the body as that though as that clamp doesn't work in that area.

I use a hammer here and there. And sometimes for replacing a few frets I use a hammer. But since I started pressing them in I prefer that method.

We have a couple of neck jigs at the workshop I share with my friend. He studied under Dan when he ran the Guitar Hospital.

[kayakerca]

I wouldn't say hide glue has ease of use! I don't use hide glue at all for anything. I used to use titebond for frets, but now I use CA.

Sorry, Titebond liquid hide glue, not a gluepot. I find it a lot easier to cleanup any over squeeze out and [maybe its only in my head] but I believe it gives me more time to clamp on a caul before it really starts to set up. I do use CA for a number of different things. I really like it for fixing chips that sometimes get created when I pull frets on rosewood fretboards. Some rosewood sandings/dust, a piece of teflon for a dam and thin CA. Yes, another technique from reading Dan Erlewine stuff.

[Rick Turner]

Haven't been around for a while, but here I am again...

Noticed the bit about Litz wire. I've done some very interesting experiments using some 7x44 Litz rewinding "classic" pickup cores...Tele, Strat, J bass, P bass, Gibson humbucker, and Guild Starfire "Bisonic" pickups. The goal was to wind the coils to an equivalent size as the originals, knowing that I'd be down at about 20% of the original turns, and then just to hear what there was to hear. As expected, the highs were greatly extended, though at the time, I didn't measure resonance. I figured it would be way out there beyond 20K, and so it really didn't matter. What was interesting was that there was a certain character to the sound of each pickup...what I call the signature magnetic tone...which carried through...there was an essential "-ness" to each pickup...Teleness, Stratness, P bassness, etc. Also, the low end was really tight and punchier than expected. In talking to high end cable designer (and bass player) George Cardas, he thought that the use of the Litz wire improved the group delay...basically the phase response of the pickups. On a couple of instruments, I ran the pickup signal out as a balanced line and went into a good studio mic preamp. Sounded great.

The thing is that the dynamic interaction between magnetic field, strings, and coil geometry stayed the same as with the traditional pickups...and that is where a lot of the sound of a pickup resides. It's not all about impedance; that is just another tool to play with.

I may have to revive this deal...I last wound the Litz pickups about 23 years ago. I even thought of making a wire feed turntable that would hold seven spools of 44 gauge wire and turn at a rate that would make the Litz wire as the coil is wound. The pre-made Litz is expensive as hell, and it's a real pain to tension being a rope twist. I usually tension with felt blocks, though I do have one of those odd magnetic drag tensioners, too, which I may have to dial in better.

[David Schwab]

Welcome back Rick!

[bbsailor]

Haven't been around for a while, but here I am again...

Noticed the bit about Litz wire. I've done some very interesting experiments using some 7x44 Litz rewinding "classic" pickup cores...Tele, Strat, J bass, P bass, Gibson humbucker, and Guild Starfire "Bisonic" pickups. The goal was to wind the coils to an equivalent size as the originals, knowing that I'd be down at about 20% of the original turns, and then just to hear what there was to hear. As expected, the highs were greatly extended, though at the time, I didn't measure resonance. I figured it would be way out there beyond 20K, and so it really didn't matter. What was interesting was that there was a certain character to the sound of each pickup...what I call the signature magnetic tone...which carried through...there was an essential "-ness" to each pickup...Teleness, Stratness, P bassness, etc. Also, the low end was really tight and punchier than expected. In talking to high end cable designer (and bass player) George Cardas, he thought that the use of the Litz wire improved the group delay...basically the phase response of the pickups. On a couple of instruments, I ran the pickup signal out as a balanced line and went into a good studio mic preamp. Sounded great.

The thing is that the dynamic interaction between magnetic field, strings, and coil geometry stayed the same as with the traditional pickups...and that is where a lot of the sound of a pickup resides. It's not all about impedance; that is just another tool to play with.

I may have to revive this deal...I last wound the Litz pickups about 23 years ago. I even thought of making a wire feed turntable that would hold seven spools of 44 gauge wire and turn at a rate that would make the Litz wire as the coil is wound. The pre-made Litz is expensive as hell, and it's a real pain to tension being a rope twist. I usually tension with felt blocks, though I do have one of those odd magnetic drag tensioners, too, which I may have to dial in better.

Rick,

I am picking up on your Litz wire observations with some of my own experiments and research.

The Litz wire that was mentioned this thread was related to the frame of the Alumitone Pickup or other current-based single string loop type of pickup. Since high frequency harmonics have very little energy, they get lost fast beyond the resonance of the traditional guitar pickup where the response drops of at 12 plus db per octave. In current based pickups the high frequencies travel at the outer area of the wire and thus present a higher impedance to the high frequencies thus presenting less current to be transformed. The use of Litz or a laminated frame in the primary string loop of current-based pickups seems to offer similar benefits to what you discovered with traditional high Z pickups wound with Litz wire.

A typical 2H pickup wound to 8,000 ohms DCR presents a time constant of 2/8000 or .00025 seconds or 4000 Hz. It is also interesting that the resonant point of many pickups is near 4000 Hz. The group delay accounts to the initial attack of the string staying in time with the upper harmonics which are phase shifted by the filter action of typical high-Z pickups near resonance. http://www.radiolab.com.au/DesignFile/DN004.pdf This accounts for the perception that the Litz wire pickups were punchier and sounded tighter because of a more controlled group delay by keeping the initial attack more inline time-wise with the phase shift at resonance.

I have played with 40/44 Litz wire making low impedance pickups to feed mic mixers also and there is a more acoustic-like sound to them espicially when you eliminate the classic high impedance pickup resonant hump that maskes the upper harmonics. I have also made humbuckers with about 100 turns on each bobbin for about 3 ohms DCR with each bobbin feeding one of a pair of 8 ohm to 20K ohms miniature matching transformers wired in series with more acoustic-like qualities also.

Playing with current transformers with a single string loop and magnet in the center with about 500 turns on the secondary makes a nice pickup in the 150 to 250 ohm impedance range depending on the thickness of the primary string loop wire. Thicker string loop primary wire lowers the output impedance. You can even make a current transformer pickup for the three lower wound strings with one size thicker current loop wire and then use a thinner wire for the higher plain strings and get a more balanced voicing.

Thanks for sharing your Litz experience.

Joseph Rogowski

[Rick Turner]

Joe (and everyone else...), I became convinced that phase response is perhaps the single most important defining characteristic of "tone" when I was heading up Gibson Labs in North Hollywood from 1988 to 1990. My chief engineer, Cliff Elion, demonstrated to me what had to have been the first guitar amp modeling...based on algorithms he developed and played through on his IBM desktop computer. He modeled a classic Marshall tube amp, and as soon as I heard it, I knew this was a total game changer, and I also immediately asked if the concept could be applied to modeling acoustic guitars. I "got it" that the signature sound of an acoustic instrument...or, really, any instrument or sound was really a matter of the phase response of the instrument as it affected the signal generator...which with guitars is the string.

I knew that we were really on to something, and so Cliff and I presented the concept to he whose name shall not be uttered...the grand poobah of Gibson...and we got totally shot down. Gibson could have and should have beaten Line 6 to market by years and years... Oh, well. And that was not the only design with incredible potential to be shot down. So, too, was my frequency doubling pickup that measured Z axis changes in string tension...which happen at 2 x F...and had the potential to halve the time it takes for a pitch to voltage (or MIDI) converter to track. So, too, was the wave slope detector circuit which could theoretically catch a note in the first quarter cycle... Oh, well...

Fast forward from 1990 to 2001 when I met the folks at Seymour Duncan and presented the concept of what became Mama Bear...which was the first acoustic guitar modeling preamp to be demonstrated in public. The R&D process on that...for which I brought back Cliff Elion to do the digital end and basic algorithms...was an incredible experience. I came away from that project having learned more about the actual acoustical workings of guitars than I could have in another 40 years of just making guitars, and a lot of what I learned was that my underlying instincts had been correct...that it's more about phase response than 20 to 20K frequency response...and that, I believe, is true of all acoustical phenomena.

The ironic thing about under-saddle or in-saddle piezo pickups is that they are more phase coherent relative to what the string is doing than any other kind of pickup. They intercept the string vibration before it gets to the top or into a solid body. The top/body/air in an acoustic or solid body guitar screws up the phase response of the input signal...the string vibration...and that f'ed up sound is what we've come to love...and it's f'ed up differently on each and every instrument, and that's the ghost we're chasing.

We got pretty close with Mama Bear, and we got universally fantastic reviews from the guitar and pro sound and recording press. I wished we'd had a continued stream of R&D bucks to do some better initial recordings...the ones from which algorithms were developed. I can still hear room artifacts in the models; recording in an anechoic chamber would have been fantastic. But it was all good enough for this to have happened:

We got to the Alpha stage...a breadboard or three plugged into a laptop computer with wires dangling, but with about eight "models" ready to demonstrate to our main golden ears musician: Laurence Juber (who does have the best ears I've ever encountered...). He was playing his prototype Martin signature model (spruce over Indian rosewood) which I think had a Fishman Matrix in it through the first test Mama Bear into one of the old Duncan acoustic guitar amps and then into some decent near field monitors. At one point Juber said, "I hear cedar and koa..." Yeah, sure...you hear two different woods superimposed over the two different woods of your own guitar? Well, we checked the algorithm list, and damn if it wasn't a ceder on koa Ed Claxton of approximately 000 size!

So that's how important phase response really is. It's the heart of the sound of any acoustical event. And that does not mean that perfect phase response is best. It just means that phase response is at the center of signature tone.

[Rick Turner]

One other observation: digital modeling is still in its infancy. As computer power increases and becomes cheaper, and as we better understand what we're trying to manipulate, these tools will become easier and easier to develop, to use, and to love, for that matter.

A funny one: When I first publicly demonstrated Mama Bear it was at the Healdsburg Guitar Festival in 2003...a venue packed to the rafters with high end acoustic guitar makers. My friend (and great guitarist) William Coulter did the demo playing while I switched algorithms and gave the talk. This thing actually pissed off some of the guitar makers. I got a couple of half-way hostile comments: "Does this make us obsolete?" to which I answered, "If someone is playing your guitar plugged in on stage, do you want the sound to suck or sound good?" And then there was, "Well, it's all very fine to have Bill playing a Traugott with one of your pickups in it, but how would that work for a shitty guitar?" I happened to have brought a mid-1980s Ovation with me for just such a moment. I plugged it in and started up on "bypass" for that traditional Ovation sound; then I kicked in the J-200 model and hushed the room...

I think the real point of all this rant is that you have to widen your ideas of what makes up guitar sound...and by extension, pickup sound. Pickups are just windows into what the guitar is doing to an input signal from strings.

[Bruce Johnson]

What Rick is saying about modeling and phase response goes right along with what I've learned from 20+ years of building electric basses. The real heart of the sound of an electric bass is in how the frame of the bass springs back and reacts when the strings are plucked. It's a complex, delayed action and reaction between the strings and the frame. They are both moving and cycling, in and out of phase with each other. It's mechanical motion. The pickup has an effect, but it's mostly just reading the complex warbling that's ending up on the strings. The purpose of the digital modeling is to recreate that complex warbling that results from pieces of wiggling wood. I personally hope that they don't get too good at it. I kind of like making the sound mechanically.