Drill Your Own Hole

No, I’m not referring to the iconic album from Gaye Bikers on Acid-
This is the real thing :sunglasses:

A recent thread on pickups for acoustics lit the GAS cannister again, forcing me to buy a Fishman Rare Earth single coil pup on fb marketplace for £50.
Initial disappointment when it didn’t work was happily relieved, by replacing two dead, corroding batteries and cleaning the contacts.
Eureka!
Now, the cable hanging out of the sound hole, reminded me too much of a patient attached to a drip or a catheter swinging out of a… well, I’ll leave it there :wink:

Even though this is my dumpster guitar, it does focus your concentration when you take a half-inch drill bit to your guitars butt and start drilling a big hole in it. The patient survived and it feels solid and works as a button for the strap too.
A plastic cable-tie and a small clamp to keep the cable tidy inside and hey presto!
One fifty quid electro-acoustic.
The in-built preamp even has enough juice to power it through my Trio+ :smiley:

I had a quick go on the acoustic setting of my THR amp and it sounds sweet to these lugs.
Quick question @majik: If I put the same pickup on @sairfingers’ Martin, or say my nylon classical would it sound essentially similar, or does the wood/resonance contribute more to the acoustic pickup sound?
Oh yes @tRONd, do your acoustics have built in pups or did you have to use a sound hole one?

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That pick-up is basically an electric guitar pickup voiced differently, so it only works with steel strings. As regards the sounds of the woods, I don’t think so, as it’s a magnetic pickup the only thing that may influence it is the vibration of the soundboard.

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There is a song for every occasion.

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Hahaha!! Had a laugh reading this Brian :rofl:
Yes, one of mine has a built in pre amp. so it was easy peasy, no drilling here :rofl:
My other dont. But im not planning on it either…

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Also, well done Brian.
Kudos for venturing forth with vorpal sword in hand.
:slight_smile:

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My first thought ? Ooo err missus !! Brave man Mr L but what a great adventure, assume audible demo to follow at some point. Am gazing at my ancient pupless Encore right now. :thinking:

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Hawkwind reminds me of Silver Machine, perhaps not inappropriate, I remember hearing this live at University when they just hit the charts. When I said heard it, I was outside as could not get tickets. Those were the days when all the top bands toured the university circuit. Nostalgia

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Wot @DarrellW said!

If it was a piezo or mic pickup, then these pick up the vibrations from the bridge, soundboard, and strings which would be different for different types of string and different soundboard woods, and guitar construction.

Cheers,

Keith

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Hi Brian. My son recently had a K&K Trinity fitted to his Martin. The luthier who fitted it drilled out the strap pin hole to suit and also fitted a thin piece of wood with the same diameter hole internally as he said that otherwise there was too much stress on the end of the guitar with pulling the jack plug out and in.

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Thanks all for the comments :smiley:
Interesting about the the strings having to be steel @DarrellW & @Majik . I just presumed they were picking up air vibrations, a bit like tiny microphones. Makes sense though.

@Richard_close2u @MAT1953 Hawkwind and Valium?!? I take it this was after jettisoning speed-freak Lemmy :laughing:

@TheMadman_tobyjenner I was going to comment that it wouldn’t be worth putting a pickup on an Encore. Considering Darrell and Keith’s comments though, install a decent pup in the purple pimple and it will sound as good as a Martin with the same system :smiley:

@sairfingers Haha that pickup alone is worth a multiple of what my guitar and pickup together cost :laughing:
I can see how luthiers and owners alike would want to take ‘extra special’ precautions to protect a valuable instrument, but the physics don’t really add up for me. I had to drill through the guts of an inch of wood at the base of the guitar, and the jack is held tightly by washers and nuts on both sides. The strap button it replaces had to take the weight of half the guitar, (plus any extra swinging around on stage), let alone the push/pulling of tight guitar straps and locks- far more force than any inserting/removing a jack could ever produce.
(Mind you, if I was paying a luthier and they recommended it, I’d probably do the same.)

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I tend to agree with you there Brian but can only assume he feels that by enlarging the hole the surrounding structure is weakened and so he fits the extra piece of wood to strengthen things up.
He actually makes guitars too so presumably knows what he’s talking about.

Not quite, they’re magnetic pickups so what they pick up is movement of anything magnetic in their magnetic field, it’s then translated to sound.

This does, of course, include any vibration of the pickup itself with respect to the strings.

Bear in mind that the construction of an acoustic guitar is based around resonating the guitar cavity and soundboard to create both tone and volume. The pickup is mounted, in part, on the soundboard, and it will get some vibrations from this.

Because the pickup is attached to something that is expressly designed to vibrate as part of the sound produced by the acoustic guitar, the vibrations experienced up by the pickup are likely to be thousands of times stronger than those experienced by pickups in a solid-body electric guitar, where the body wasn’t really originally designed to be resonant or to transfer any vibration to the pickups: it was designed to be stiff and relatively inert (to increase sustain) and in the case of Fender guitars, cheap and easy to manufacture.

Bear in mind the original wood used by Fender was chosen not for its “tonal properties” but because it was cheap and readily available, and they have changed wood types used in subsequent years based on wood supply and cost factors.

But, back to the acoustic guitars… It’s clear that the vibration experience by a pickup attached to the soundhole of an acoustic guitar is likely to be significantly higher than that of a solid-body electric pickup.

But, the question is: how significant is this effect?

A subsequent question is: is it beneficial or detrimental? (There’s no reason to assume vibration in the pickups is a positive thing).

For these questions, I have no answers.

Personally, I suspect the impact of the vibration will be negligible, but I have nothing to support that.

Cheers,

Keith

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The vibration of the soundboard compared to the strings is very small, it’s something I looked at while I was still working. We had a rig for measuring sonic resonance in structures; it was easy for me to do a few measurements in my lunchtimes, the movement for a decent range of pitches was in 100ths of a mm, if it wasn’t buffered in the design of the pickup it could maybe cause low level sound but I suspect it would be filtered out by the electronics if it were a problem.

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Does the attachment of a sound hole pickup then dampen the vibrations of the soundboard mechanically to the detriment of the guitar sound?

I read about armrest attachments for acoustics and one argument for them that is frequently made is that they keep your arm off the soundboard allowing it to vibrate like it is meant to.

I don’t know the validity of this or the magnitude of the effect of it is valid, but I haven’t looked up the effects of sound hole pickups. It would make sense that they would also have some effect, however minimal. Interesting. :face_with_monocle:

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Because it is the vibrating wood of the guitar that causes the sound and you are effectively adding a brace to it, I’m going to say yes.
Would anyone who frequents a site like this be able to detect that tiny difference?
I seriously doubt it :wink:

Thinking about it, I think it would be more about mass added to the soundboard. Since it really doesn’t oscillate around the hole. Another common discussion about this kind of thing is with brass bridge pins, which add mass and therefore may effect sound.

I agree that it is all nuance, most likely. For argument in guitar forums rather than real world impact.

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@DarrellW & @Majik delving a bit deeper down the rabbit hole, I came across an interview between Seymour W. Duncan and Seth Lover (inventor of the PAF humbucker).

This bit I found particularly interesting:

“You’ve got to get the pickup as close as you can to the strings.”

“Because you’re losing your magnetic field?”

“That’s right, the magnetic field comes up to the stings there and magnetizes the strings. That’s one of the things that most people don’t understand. They figure that string is waving there and cutting the magnetic lines of force. Nuts. That isn’t it. The magnet, all it does is magnetize the string. Now you’ve got a waving magnetic field. And we have a fixed coil with a waving magnetic field to induce voltage. If you want to, take the magnet out. One you’ve magnetized your strings, it will play until the string loses it. Players think the string, the magnetic field from the magnet comes up to the string and by twisting the magnetic flux back and forth that’s what induces the voltage. That’s not what happens. There’s a certain amount of that, but that’s minor. What is happening is you have a magnetic field that is moving back and forth across the coil. And when you move a magnetic field back and forth across the coil you induce voltage. If you move the field up and down it wouldn’t induce any voltage. It’s the motion back and forth across the pickup that does it.”

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Is that respect for performing surgery on my guitar, or “Really?” for my pickup research comment? :rofl:

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