Adjustable Tailpiece?

[sgcim]

I've been playing around with the adjustable tailpiece on my Borys B-120, and I decided to let it pop all the way up, with the screws nearest the bottom of the body. It seemed like there was less string tension, but
this made it impossible to achieve good intonation, so I let it go down a bit, and it intonated better.

I played it with two groups; a big band, using my JazzKat amp, and it sounded good, and then I played it with a jazz quartet, using the pianists amp, a big Crate acoustic amp, and I couldn't get the usual good sound I get out of it.

Roger Borys told me that the tailpiece can be adjusted to get either a full archtop sound, or a semi-hollow body sound.
Then he gave me the explanation of why it changes the sound and string tension, but it was so complicated, it just went in one ear and out the other.
Does anyone understand what the adjustable tailpiece is all about?
TIA

[Ol' Fret]

Does anyone understand what the adjustable tailpiece is all about?TIA

Yes, I think so... raising or lowering the tailpiece can change the 'breakover angle' of the strings (on the bridge), hence also changing the amount of downward force. The overall effect of this device is quite subtle - it's very hard to detect any tonal differences of smaller changes of the breakover angle (just two or three °) just by ear (blind study).
Another tailpiece allowing to change the breakover angle (again quite subtle) of individual strings is the ABM 'finger' tailpiece.

A larger change of the breakover angle is a well-known influencing tone variable on acoustic guitars; not so much on electrics. Newer studies have shown that the breakover angle is more important for the exact defining of the vibrating string length (pitch).

One drawback of such non-hinged devices is that with any change of the breakover angle you're also going to change the angle between the strings after the bridge and the string attachment on the tailpiece (red circle on the sketch below), sometimes resulting in more 'sympathetic resonances' (usually unwanted vibrations of the afterstring length and the tp) of large metal tailpieces. On hinged tp's that angle will automatically be 180°.
Btw., these unwanted resonances can be suppressed by Harry DeArmond's control boxes, firmly attached to the afterstring length - one more reason for the success of the 1000/1100 pickups. Roger Borys was aware of this problem, since he "tuned" the tailpiece's brass legs "to minimize sympathetic vibration" (http://www.allthingsemily.com/pdfima...sBrochures.pdf ). I can't tell if this attempt has been successful - or not.

[sgcim]

Thanks for the explanation. The tailpiece of the (modified) B-120 in the photo has the screws in the same position as mine is now. That would be the position for looser string tension, correct?

[Matt Cushman]

The position of the tailpiece effects the strings breakover angle at the bridge. In the raised position, the breakover angle is reduced. The breakover angle effects the amount of downforce on the bridge applied by the strings. The greater the angle, the greater the downforce on the bridge. The difference of 2 or 3 degrees has only a slight effect on the downforce at the bridge. A heavy set of strings will go from around 28 lbs. at 12 degrees to around 32 lbs. at 15 degrees. The tension of the strings is not changed, only the downforce at the bridge. String tension is effected by scale length, string gauge, and tuning.

[DanielleOM]

I find it interesting that this tailpiece increases the length of the strings in the middle. I see some other makers doing the opposite where they use the tailpiece to decrease the length of the middle strings.

[sgcim]

The position of the tailpiece effects the strings breakover angle at the bridge. In the raised position, the breakover angle is reduced. The breakover angle effects the amount of downforce on the bridge applied by the strings. The greater the angle, the greater the downforce on the bridge. The difference of 2 or 3 degrees has only a slight effect on the downforce at the bridge. A heavy set of strings will go from around 28 lbs. at 12 degrees to around 32 lbs. at 15 degrees. The tension of the strings is not changed, only the downforce at the bridge. String tension is effected by scale length, string gauge, and tuning.

So is the playability or sound of the guitar affected by reducing the amount of downforce on the bridge?

[Matt Cushman]

Downforce will effect sound but not playability. Too much or too little angle can kill the acoustic response of the archtop guitar. If there is too little downforce the strings could possibly pop out of there notches in the saddle while using a heavy picking style. This is not likely as most guitars have at least 10 to 15 degrees of breakover .

[neatomic]

in practical terms a very sharp bridge angle will takes some of the warmth and rubberiness out of the tone..but fundamental notes will be well defined...little bit of crisper sharper tone

a shallow break angle from tailpiece to bridge, will result in more overtones..the secret of the fender jazzmaster..with it notoriously shallow break angle..the problem as mentioned by mc above is that the strings can jump the saddles...so string choice becomes crucial..when leo invented jazzmaster they were using 13 flats!!

same tricks apply at nut end...string trees and amount of winds around tuning posts affect tone

as i've said before-- everything matters


cheers

[Bezoeker]

I recall the Benedetto experiments (very unclear how scientific they were) suggested that anything more than "enough" made no noticeable difference whatsoever in sound.

I recall enough being in the 7 degree range.

I have never, ever heard or measured any sound difference whatsoever via changing break-over angle except when getting to extremely low angles - so low that it would be nearly impossible to play.

Note the very low angles on a Maccaferri guitar.

There is close to zero movement of the entire top on an archtop guitar as a single large surface. Even the lowest frequencies are made via vibrations of subsections of the top.

In my opinion, this is part of why even major changes in the downward force on the entire top have little to no effect on the sound. (In my opinion, no observable effect.)

A normal (not Maccaferri) flat top does not use downward force on the top. The top is under tension via torque - pulling up behind the bridge, pushing down in front, and twisting at the sides. What a mess. But in any case the question of downward force there does not apply the same way.

Love reading the Matt Cushman posts.

BZ

[sgcim]

Were you being sarcastic when you said you love reading Matt Cushman posts?
You seemed to disagree with everything he said!

[Bezoeker]

Absolutely not sarcastic at all.

We do not need to agree or have identical experiences for me to respect a thoughtful and experienced (as best I can tell) view.

BZ

[Matt Cushman]

It should be pointed out that the breakangle on most guitars can only be can only be altered by 5 or 6 degrees. So if you want to do a radical change to increase the angle you will need to reset the neck to get an angle much greater than about 15 degrees. I can tell you that you must know your breakangle and how much downforce you expect when you carve your top and back. I have built over 60 carved topped instruments both mandolins and archtop guitars. I carve and tune the top and back by deflection testing. That means I apply a predetermined amount of downforce on the plates at the bridge to measure how far the plate will deflect under this set amount of pressure. It is this matching of flexibility of the plate to the expected downforce at the bridge that makes the final voice more predictable. Only well made carved top guitars are effected much but I can tell you that too much or too little downforce can, as I said earlier, kill the sound. Most of my experiments have been on mandolins and I can tell you, if you go from the standard 22 degrees down to say 15 degrees, your mandolins' voice will likely be killed or significantly altered.

[sgcim]

I asked Roger Borys for a SIMPLE explanation (minus all the jargon) of the effect on playability and sound on his laminate B-120 model and this is what he emailed me:

When the tailpiece is all the way down, it puts more pressure on the top. It feels different and sounds different. I just tell people to try it in the middle,and play it a while to get used to it. Then adjust it up or down to see if you like it.
I usually set them up a little more than halfway down.
Some people say it responds faster when lower, and more like a classical guitar when up. Some say it feels looser when up. Guys that play low action, fast, usually like it lower. I actually don't like it all the way up, but a few people do. And I don't like it all the way down either, but some do.
I recommend that you put it a a little lower than halfway.

[Ol' Fret]

Cool to get an answer from the master himself! We have to consider that this adjustable device was probably developed in the 1980s, when almost no archtop builder thought about such minor matters. I like the rigidity (well, the assumed rigity, from looking at the pics) of Mr. Borys's (guitar... ) tailpiece.

I'm thinking about shifting a long and thin (= relatively elastic) brass tailpiece one or two millimeters upwards according to the "Borys method". You can see the not so uncommon problem of carved archtops with higher arch, on the pic. The tailpiece is almost touching the arch, depending on the season and RH changes.




You simply could increase the tailpiece angle (red circle), which in turn would decrease the already not so pronounced break-over angle. You could bend the tp lengthwise, resulting in a further decrease of rigidity. You could replace the whole thing... not what I'd want on a quality acoustic archtop. Of course, you could also do a neck reset to increase the neck angle of the guitar, which for my taste is set a bit on the small side.
If you turn on one screw, other parameters are often also affected. It's that special fascination of simple looking devices like archtop guitars, sly old dogs...


Besides the rigidity and weight of a tailpiece, the after-length of the strings - or, in other words, the length of the tp in relation to the string length - can affect the sound. Some skepticism is appropriate, we're getting in pseudoreligious areas, though violin makers basically stick with the after-length of 1/6 of the open string length. According to Alan Carruth "that means that it _should_ vibrate at six times the frequency of the _open_ string. That's two octaves and fifth. Any time you play a note that has that overtone in it the backstring will sound as well, stealing some energy from the string and lengthening both the 'attack' and 'sustain' a bit. That's the theory. In practice the pitch may not be all that exact: even a small change in the short afterlength can change it noticably, after all. At any rate, the back strings are pretty light, and may not be able to store enough energy, or exert enough force, to make a big difference in the sound. Usually they just seem to be annoying."

While the academic debate on the correct after-length in the archtop-related cello world is going on (for example: STRING "AFTER-LENGTH" AND THE CELLO TAILPIECE: ACOUSTICS AND PERCEPTION | Anne Houssay - Academia.edu ) , the choosing of different string after-lengths on the same tailpiece is more of a visual distinctive feature of guitar brands than actually founded in science. While this doesn't affect the tensions of the strings (no change at all), it is known by the luthiers that some players can well feel the difference on the strings, caused by friction issues. It's called "compliance" (Lutherie Myth/Science: Human Perception of String Tension and Compliance in Stringed Musical Instruments ).


Nobody knows what over time in the guitar world will stay of 'sympathetic string resonance', 'aliquot stringing', '3rd bridge extended playing technique' (as seen on the Fender Jazzmaster and Jaguar).
For me, one thing is clear: my favorite archtops show the after-length of 1/6 of the fixed scale length. Would I be able to hear a deviation of a few millimeters? In no way... but I'm convinced that I'd perceive the difference immediately if that luthier had not thoroughly thought through dozens of other constructional and sound-related archtop parameters. Btw., the after-length on the guitar pictured above, sort of a Stromberg Master 400 copy made by a well-reputed US luthier, is about 1/11 of the scale length.

How close some master archtop guitar makers follow the violin world techniques can be observed, for example, with Ken Parker, whose guitar design can now even be admired in the Metropolitan Museum of Art. If you check one single violin publication from 2006 (http://josephcurtinstudios.com/artic...ect-to-change/ ), it becomes clear where Mr. Parker's archtop ideas are mainly derived from. His guitars are neither conceptually nor financially on my wish list, but I appreciate his extraordinary openness to orient himself by the art of violin making.

[sgcim]

Ken Parker claims his ideas for his new archtops were derived from the lute rather than the violin.

I found it interesting that both Parker and Borys started out as furniture makers, and then moved on to guitars.

Roger told me a story about a lay-off that occurred in the furniture building company he worked for. All his furniture making friends were out of work, so he started building guitars. When they wanted to re-hire him, he decided to stay with guitars.

[Ol' Fret]

Ken Parker claims his ideas for his new archtops were derived from the lute rather than the violin.

Parker is a smart guy... he's not wrong because historically seen the violin making was derived from lute making. Anyhow, the archtop guitar has much more to do with the instruments of the violin family than with lutes.

Roger told me a story about a lay-off that occurred in the furniture building company he worked for. All his furniture making friends were out of work, so he started building guitars. When they wanted to re-hire him, he decided to stay with guitars.

No doubt he would also have become an outstanding furniture maker - yet we are all glad that he opted for guitars!




"First thing you do is check out the acoustics in the hall, and then find the fire axe!" - Charles Mingus -
Advice to young musicians, relating to an incident with a fire axe that got him thrown out of the Duke Ellington band in 1953.

"Electricity plays with you - not vice versa!" - Charles Mingus -

[wzpgsr]

I've been playing around with the adjustable tailpiece on my Borys B-120, and I decided to let it pop all the way up, with the screws nearest the bottom of the body. It seemed like there was less string tension, but
this made it impossible to achieve good intonation, so I let it go down a bit, and it intonated better.

I played it with two groups; a big band, using my JazzKat amp, and it sounded good, and then I played it with a jazz quartet, using the pianists amp, a big Crate acoustic amp, and I couldn't get the usual good sound I get out of it.

Roger Borys told me that the tailpiece can be adjusted to get either a full archtop sound, or a semi-hollow body sound.
Then he gave me the explanation of why it changes the sound and string tension, but it was so complicated, it just went in one ear and out the other.
Does anyone understand what the adjustable tailpiece is all about?
TIA

Reviving this thread. If I wanted to tend more towards the semi-hollow sound, would I move the tailpiece on my recently acquired (thanks Vinny!) B-120 up or down? Right now there's a bit too much low-end resonance for my tastes and playing style.

[gitman]

Judging from my own experiences with two Borys guitars and my Trenier Jazz Special the moveable tailpiece makes for an audible influence on the response and color of the acoustic tone :
lowering the tailpiece increases the down-pressure of the strings onto the bridge and this makes the tone a little sharper, snappier and it looses a bit of wholliness whereas less pressure on the bridge increases sustain and the guitar sounds softer. To decrease/control the bass content your best bet would be a simple EQ pedal in front of your amp that lets you cut the frequencies below ca. 100 hz -
or whatever is needed in the room you're in and the volume level you play at. The B120 is a little more shallow than say an ES-175 (2 3/4" ?) by design to tame the bass response of a deeper guitar like an L5 and the like. Lighter strings and lowering the pickup will also make a difference but to make it sound like an ES-335 will not work IMHO.

[wzpgsr]

Judging from my own experiences with two Borys guitars and my Trenier Jazz Special the moveable tailpiece makes for an audible influence on the response and color of the acoustic tone :
lowering the tailpiece increases the down-pressure of the strings onto the bridge and this makes the tone a little sharper, snappier and it looses a bit of wholliness whereas less pressure on the bridge increases sustain and the guitar sounds softer. To decrease/control the bass content your best bet would be a simple EQ pedal in front of your amp that lets you cut the frequencies below ca. 100 hz -
or whatever is needed in the room you're in and the volume level you play at. The B120 is a little more shallow than say an ES-175 (2 3/4" ?) by design to tame the bass response of a deeper guitar like an L5 and the like. Lighter strings and lowering the pickup will also make a difference but to make it sound like an ES-335 will not work IMHO.

Thanks. It's not so much the bass response as it is the overall character that I am looking to tweak a little bit. I am comparing the feel and response to the Fender D'Aquito Elite I recently sold, which was designed by Jimmy D'Aquisto and has an adjustable tailpiece like the B-120 and 2.75" depth. That guitar was softer, which is what I am looking for, and I do note from pictures that I just dug up that the tailpiece on that guitar was set higher than halfway, whereas on my B-120 it is set lower than halfway. So maybe I will try a bit higher to see if that gets me where I am trying to go.

[ccroft]

I'm interested in hearing about your investigations Wzp!

[gitman]

I also own a Fender D‘Aquisto Elite model but that guitar does not really compare to the handbuilt guitars like my Trenier or those from Roger Borys. It has the adjustable tailpiece but it’s impact on the basic tone and feel of the guitar is barely noticeable for me.

[skykomishone]

Man, I sure miss Matt Cushman!

[zephyrregent]

I have a Trenier Jazz Special with an adjustable tailpiece. There is a sharp end on the tailpiece assembly on the bottom of the guitar. If I lower the tailpiece, it will stick out at the bottom of the guitar, presenting a sharp edge. I don't understand that as it could get caught on something. I have never adjusted it. It is most of the way up now and feels fine, with good sustain and smooth tone. Has any other Trenier owner adjusted it so that part of the tailpiece assembly sticks out?

[skykomishone]

Could you please provide a picture of what you are describing? Thanks.

[zephyrregent]

[QUOTE=skykomishone;1309539]Could you please provide a picture of what you are describing? Thanks.[/QUOTE

It's not a clear photo but the best I can do with the computer's webcam. It shows the point at the end of the tailpiece assembly.