Acoustic Bass Guitar Setup?

[sdgrfan]

In this section, we have setup guides for electric basses. And I've found setup guides for acoustic 6-string guitars. But I (and many others) have these strange instruments called "acoustic bass guitars" and they are a bit different.

Due to the way they are played, I'm not sure that setting them up just like an electric would get the best volume out of them. After all, the strings are not breaking any magnetic fields, just vibrating the top of the guitar and the saddle/bridge. And with thicker strings, I doubt that standard acoustic 6-string guitar setup guides would give the best results either.

But there are a LOT of manufacturers out there who offer ABGs. Has anyone ever seen a setup guide or manufacturer's specs on these? Specifically, I'm interested in string height/action.

Thanks all.

 

[Arie X]

basically they are set up similar to an acoustic guitar. same principles. tbh, actual "numbers" don't really matter much. what does matter is:

-playability -all the factors that contribute to playability ie: neck relief, string height, neck angle, nut height, saddle height, etc..
-intonation -does the instrument present a clear (enough) and well intonated note at all frets.

in general, set-up is going to vary. one person's "great action" is not going to be someone else's. some people like to "dig in" and work the guitar using main force, thick strings and higher action is ok for these folks. others like easy playing and thin strings and so a low action is called for. some buzzing here and there is ok for them. basic rule of thumb is to go as low as you can get away with unless required otherwise. playing an instrument should be an enjoyable and pleasant experience not an MMA match. damage to one's hands can occur from duking it out with an uncoperative guitar for extended periods.

some basics:
-the truss rod sets neck relief, it isn't the "action adjustment rod".
-string action is set by saddle and nut height.
-nut height (slot depth actually) is measured between the bottom of the strings and the top of the first fret with feeler gages.
-intonation and comp. is set by the saddle ramps.
-i check relief with capos on the 1st and 12th fret but ocassionaly at the body joint fret for a comparison number. feeler gages are used between the 3rd and the 7th fret. a wider area gives you a better "map" of the relief geometry rather then just checking under one fret.
-string height is measured at the octave or the neck joint (depending upon scale length) using feeler gages and is best checked under all of the strings not just two.
-intonation is checked at the octive using the fretted note and the harmonic, but if the string action is initially too high, you'll pull that note sharp when fretting it. which is one reason why you'll be jumping around to all of these measurements as you dial in the instrument.
-neck angle is checked with a precision steel straight edge laid out on the fretboard edge up. the rule is slid up to the bridge. if it clears the wood by at least 1/16" you're ok; but this is on the low side. 3/32"~1/8" is where I like to be. gives more room if the saddle needs work and maintains a decent string ramp angle.
-setting up with new strings is fine but they should be played in and well set. i suggest doing a rough set-up and going back a week later and checking and adjusting as needed. do this for a total of three sessions.
-build quality and/or prior repair integrity of the instrument. assumptions are that any guitar can be set up like a champ and stay that way forever. not true. poorly crafted instruments often do not hold a competent set-up for very long due to construction deficiencies. poorly done previous repairs can cause or allow to happen changes in the guitars geometry that will effect the ability to maintain a solid set-up.
-temp and humidity. steady even temperatures are best. drastic hot/cold changes are not. humidity wise you either want 40%-50% RH maintained, or the current RH level when you did the set-up to be maintained. acoustic instruments are picky that way.

 

[lz4005]

But there are a LOT of manufacturers out there who offer ABGs. Has anyone ever seen a setup guide or manufacturer's specs on these? Specifically, I'm interested in string height/action.

Specs are a false idol. Make it sound good and feel good for how you, as an individual, play. Measure last if you need numbers to feel like the world makes sense.

Start with a similar setup you'd use on an electric and refine from there. Read the acoustic guitar guides for how to work with a bridge saddle to intonate and adjust string height. Everything on an ABG is the same, only bigger.

 

[sdgrfan]

I hear you guys and agree...to a point. But how many instruments need a good setup, even when new, to play their best? Yes, personal preference comes into play. But how many people complain about their guitar/bass being a hard-to-play, out-of-tune, buzzing piece of crap when all it really needs is a good setup with neck relief, string height, and intonation adjusted?

I would certainly agree that for a seasoned player, you just know what feels right to you. You know the kind of action you want. And you probably do your own setups without ever pulling out a ruler or a feeler gauge.

But the truth of the matter, IMO, is that the market is being flooded more and more with Asian instruments that are sold without a setup ever being done on them. It takes time and, therefore, money to tweak these things in for optimum playability. Yes, you can pay for a professional luthier to do it for you, but he/she is probably going to ask you how you want it.

So while specs may be a false idol, engineers and manufacturers do (or should) spec them. They are, of course, not reflective of the finished setup. But they are a good place to start.

 

[Bruce Johnson]

Arie X covered it thoroughly;

I just want to point out that the big difference between an electric bass and an acoustic bass is that, on an acoustic bass, the action height is directly related to acoustic volume; how loud it is. Higher action doesn't cause the instrument to be louder, but it allows it to be played harder. You control the volume by how hard you hit the strings.

The louder you want to play, the harder you have to hit the strings, and the more physically punishing it is to play, because of the higher action needed.

So, there isn't any one good answer on how high the action should be. That would be like asking how big an amp do I need? It depends on where and how you intend to play it.

If you normally play electric bass, and you bought the acoustic bass to use for casual practicing in your living room, then you should set the action about like your favorite electric. Play it with that same technique. It won't be very loud, but it will be familiar and comfortable.

If you bought the acoustic bass so you can hang out with your buddies under the trees, and they have five acoustic guitars, three mandolins and a very loud banjo, that's a different thing. You need to set the action as high as you can stand to play it, and learn to pound on it. You've got to be loud enough to keep those goats herded. And electric bass level action won't cut it.

 

[Arie X]

""...But how many instruments need a good setup, even when new, to play their best?""

-suprisingly, most. but there are players out there who are not aware that a set-up can help. some give up the guitar because of issues that could have been solved with good regulation.

""...But how many people complain about their guitar/bass being a hard-to-play, out-of-tune, buzzing piece of crap when all it really needs is a good setup with neck relief, string height, and intonation adjusted?""

-guitar forums are full of them. i'm on pretty much every relavent guitar forum out there, and i would assume a good 25% or more of players have issues with their instruments.

""...It takes time and, therefore, money to tweak these things in for optimum playability. Yes, you can pay for a professional luthier to do it for you, but he/she is probably going to ask you how you want it.""

-agreed

""...But they are a good place to start.""

-agreed again. specs. are necessary to manufacture something -of course, and they often don't reflect the adjustments of the end user. Ibanez, Fender, and Warwick all have good guidelines to a baseline set-up. Martin and Taylor also have them, but an acoustic instrument is a more "in flux" organic construct that is more so dependent upon end user and environment and is accordingly much more harder to constrain with "set-it and done" specs then solid body instruments. For example, classical guitars of quality are often supplied "summer" and "winter" saddles to help the owner cope with weather changes. These are not needed with a solidbody guitar.

 

[Arie X]

Bruce,

""Higher action doesn't cause the instrument to be louder, but it allows it to be played harder. You control the volume by how hard you hit the strings"".

Regarding action, partially true. Assuming that the higher action is not caused by a failed neck angle or top roll-up condition. In an acoustic, higher saddle height induces more torque to the top and it's bracing system. It in effect becomes a more sensitized amplifier do to the increased leverage and string energy that a taller saddle provides to the top.

In guitars with very tall saddles, the system "tops out" -notes are louder, but distorted as the air volume of the box is overwhelmed with string energy and the guitar can't dump it out fast enough. Porting can help here but again with any organic construct there are cause and effect consequences to consider.

Guitars with short saddles impart less leverage and string energy to the top causing the sound to decay quickly, notes have lower volume, and they produce an overall weaker excitation of the bracing system.

Bottom line: assuming relavent guitar geometry is correct, and the same picking/plucking force is applied, and the same string gage and the same string tension (tuning) is used, a guitar with a higher saddle height will be louder due to increased top leverage and what we call bridge torque, then a guitar with a lower saddle height.

 

[Bruce Johnson]

Bruce,

""Higher action doesn't cause the instrument to be louder, but it allows it to be played harder. You control the volume by how hard you hit the strings"".

Regarding action, partially true. Assuming that the higher action is not caused by a failed neck angle or top roll-up condition. In an acoustic, higher saddle height induces more torque to the top and it's bracing system. It in effect becomes a more sensitized amplifier do to the increased leverage and string energy that a taller saddle provides to the top.

In guitars with very tall saddles, the system "tops out" -notes are louder, but distorted as the air volume of the box is overwhelmed with string energy and the guitar can't dump it out fast enough. Porting can help here but again with any organic construct there are cause and effect consequences to consider.

Guitars with short saddles impart less leverage and string energy to the top causing the sound to decay quickly, notes have lower volume, and they produce an overall weaker excitation of the bracing system.

Bottom line: assuming relavent guitar geometry is correct, and the same picking/plucking force is applied, and the same string gage and the same string tension (tuning) is used, a guitar with a higher saddle height will be louder due to increased top leverage and what we call bridge torque, then a guitar with a lower saddle height.

Okay, you are right, the action height/saddle height does affect the loudness of the instrument itself, to a degree. But my point is still that the overall loudness of an acoustic bass is primarily based on how hard you pluck it. And the harder you want to be able to pluck it, the higher the action needs to be. Which will usually also make the instrument itself a little louder too. If you set the action low to make it comfortable, you are limiting how loud it can be played.

 

[sdgrfan]

You guys bring up what is, to me, an interesting contrast between a "normal" electric bass and an ABG. I play mostly jazz, country, and soft rock. As a result, I have my Ibby set really low on action. I'm not into Death Metal or even slapping, so my electric is setup up for fast action. Yes, it can get louder by playing more aggressively, but I control 90% of the how loud it gets with the preamp and amplifier.

The ABG is, to me, a unique instrument. Yes, I could file the saddle and the nut down and get a really low setup. But I'm not using it as a "woodier" alternative to my electric. Rather, I'm using is as a lower tuned guitar where I can play some melody, some accompanying chords, and, of course, a bass note here and there to anchor things. Playing it in this manner, at least for me, I need a higher action than my electric. Why? Precisely due to what has been said -- to control volume for dynamics. The main volume control is done on my ABG through my attack on the strings.

So I wasn't so much looking for specs that shouldn't be changed. We musicians love to tweak our stuff! I'm just wondering, on these ABGs, where the typical action is. Mine is sitting at 4.5mm on my E at the twelfth fret. My Ibby is set at 3mm - quite a difference in the feeling of fretting. And I've read reviews of these things were the action at the twelfth fret is .5 inches. That's crazy high to me. I can't imagine that ABG ever having proper intonation. Again, I'm not looking for a precise number, more of a range. I don't see where any of the major players in the ABG manufacturing world publish their setup specs. But these instruments can do some wonderful music. Check out the music by Dmitry Lisenko on his ABG. It's not Jaco's bass. But it's not meant to be.

 

[202dy]

Three millimeters is roughly seven and a half sixty fourths. Most people would find this objectionably high on an electric. Back in the fifties and sixties when many double bassists were transitioning to the bass guitar that was a pretty typical string height.

Four and a half millimeters is roughly eleven sixty fourths. Most people would find this ridiculously high on an acoustic. But it should bring some volume to the party.

If someone likes their guitars set up that way and the intonation is acceptable it's a home run!

 

[sdgrfan]

I hear ya, 202dy. I wanted to bring the action down on my new Takamine. So I pulled the saddle up only to find it is an Ovation-style thinline where the saddle is cut to fit into a metal slot. Ovation makes up for this by putting shims under the saddle. There was only one shim in mine so I removed it and now the action is at 4mm -- not much of a difference. The neck angle is okay and the relief is quite minimal, though there is no buzzing anywhere (a good thing). If I really wanted to lower it further, I would need to route the saddle slot out deeper in the bridge, and I don't think I want to do that. I guess I'll learn to live with it and make the best of it. I might also try to lighter gauge strings on it to lessen the tension on the neck and straighten it out a bit more, though I would lose some volume with lighter gauge. Always tweaking!

 

[sdgrfan]

Update: The action on the Takamine (4mm) was just too high for me. Too hard to play and I simply couldn't "learn to live with it". It would have required a neck reset to fix it and I wasn't about to do that. So I returned it to the seller.

What I ended up buying is a 2007 Fender Victor Bailey ABG (shown in my avatar). The thing about this bass, besides being stunningly beautiful, is that Victor Bailey worked with Fender to have an acoustic bass produced with a Fender Jazz neck on it. It also has a piezo pickup under the saddle and an ACLR pickup under the bridge, both by Fishman. With what is essentially an electric bass neck on this ABG, I did the setup exactly as I would an electric bass and everything came out fine. The neck relief is at .020". The action is at 2.5mm bass side and 2mm treble side, really low but with no buzzing anywhere. If, as I proceed with learning the ABG, I find I need a bit higher action, I can always put a shim under the saddle and, surprisingly, this "used" bass came with the original kit (extra shim, string peg, allen wrench, documentation, etc) for doing so.

So now I have an ABG that sounds like an ABG but plays like an electric bass. Nice!

 

[LoveJackBruce]

The strings at the 12th fret are about 7mm off the fretboard of my new Fender CB-60SCE. I'm concerned there won't be enough saddle to shave. Should I send this back? And maybe upgrade to an Alvarez AB60CE?

Thanks. Keeping me up at night.