Howard Roberts Fusion II tailpiece

[jaymen]

I saw a Gibson Howard Roberts "fusion II" at a NAMM show back in 1993. It had 2 humbuckers, a body that was similar in shape to the ES-175,gold hardware, and a very interesting tailpiece with 6 fingers that each had what appeared to be fine tuners.

Anybody here have the low down on that tailpiece? If so please elaborate on how it works and if you like it.
Thanks,
Jay

[setemupjoe]

Gibson used it on various models. Here is my 1980 Super V. The individual knobs aren’t tuners. They are to set tension for each string. I think it’s commonly called a fingers tailpiece. I find it attractive but I know people who are not fans.

[stevo58]

That’s an ABM 1500 tailpiece:

ABM 1500g Gold Finger-Saitenhalter

It’s basically a guitar version of the Oettinger tailpiece for banjos. It’s not intended to change the tension on a string, though I suppose you could use it as a fine tuner; rather it changes the downward pressure of a string on the bridge, which will change the volume of that string. It is used especially on tenor banjos, where the high A string has extremely high tension and is often much louder than the others.

Here’s how to set one up:

How To Set Up An Oettinger Tailpiece

[pauln]

If you imagine a guitar with a locking nut and a locking bridge saddle so that the length of the available string that can stretch equals the scale length, it will have a certain required pressure to depress the string to a fret. If you imagine the same guitar where the string extends past a regular nut with a tuning post behind it and a regular bridge saddle with more string beyond that to the tail piece, that string at the same tuned pitch (same tension) will feel much more "slinky" and easy to fret because the string has more string length with which to distribute the stretch - because it includes the additional string length behind the nut and beyond the bridge saddle.
The amount of string (mass, a function of the gauge) also determines how much string length is required (less) to distribute stretch and balace the feel. There are string sets designed to approximate an equal "feel" of pressure required to fret all the strings, but individual guitars use different arrangements outside the scale length (head stock and tail piece areas).
This HR tail piece looks like it uses the different finger lengths to provide a first approximation to the balanced feel (adjusting gross non-sounding string length behind the bridge following relative string gauge). Each finger looks like it has a range of extension adjustment to dial in more precisely for particular string sets. Notice in the photo that the D and G fingers appear to be the same length, so you can get an idea of how much the fingers can slide to change their adjustment.
What is amazing is how attractive the resulting solution to a pretty challenging problem, very elegant, understated, and clever.

Edit... I didn't even think about varying individual strings' direct pressure on the bridge to manage relative string volume. Everything I wrote about how nice a solution... times two!

[jaymen]

Very interesting.
I read the adjustment instructions and noticed something missing: they fail to mention re-tuning the string to pitch after adjusting the finger/s. Obviously the pitch increases with the angle of the string over the bridge when adjusting the finger down, and vice versa. They do however mention having to do several rounds of the adjustment procedure to get the instrument balanced due to the interaction between each string. In the picture above of the guitar, the fingers appear to be in reverse order(short trebles, longer bass).

Thank you everyone for the great replies!

Jay

[stevo58]

Very interesting.
They do however mention having to do several rounds of the adjustment procedure to get the instrument balanced due to the interaction between each string. In the picture above of the guitar, the fingers appear to be in reverse order(short trebles, longer bass).

Those instructions are for a banjo, which involves a drum head. Changing the break angle of a string will change the amount the head is depressed, which will change the pressure the other strings put on the bridge. So you have to circle around it, making finer and finer adjustments until it is right. That shouldn’t be necessary- or at least not to the same degree - on a guitar.

if a string breaks on a banjo, all the others detune.

[Hammertone]

Those instructions are for a banjo, which involves a drum head. Changing the break angle of a string will change the amount the head is depressed, which will change the pressure the other strings put on the bridge. So you have to circle around it, making finer and finer adjustments until it is right. That shouldn’t be necessary- or at least not to the same degree - on a guitar.

if a string breaks on a banjo, all the others detune.

String breaks on a banjo? I call that a good start.

[stevo58]

<sigh> Banjo jokes? Before we go down that road, listen to Jimmy Mazzy or Cynthia Sayer.

besides, this is the best-ever banjo joke:

[Wim_Venema]

Where did you find the adjustment instrctions?

[sgosnell]

Read post #3.