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Hey could anyone be so kind to give me the specs for setting up an acoustic bass guitar?

Relief = ?
Height at 1st fret = ? ( All 4 strings)
Height at 12 4th string = ?
Height at 12 1st string = ?

Never set one up and have 2 to setup
By Christmas.

Thanks for any help

Oris


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Relief = minimal .003" or a bit more treble side and .005 or more on the bass side, of course we have to accept less than optimal on the treble side or the bass side to conform at times. So I observe the treble side and if it has more relief than the bass side, not what we want... I take the bass side pretty straight such as .003" relief and the treble side will have more than optimal relief but that's better than no relief or backbow.

Height at 1st fret = Forget it we don't use the first fret except for how we cut nut slots which is a different conversation. We measure action at the 12th and that's a pretty standard industry thing. The nut slots should be cut properly before you adjust action. It's a bit of an art to do very well and take them low but not too low. Not something that is easy to explain here although I've tried many times.

My approach to setting up an instrument is:

1). Adjust truss rod
2). cut nut slots (all other specs will be changed if you do not do the nut slots first)
3). observe action at the 12th
4). set to specs at the 12th
5). play every note to make sure they don't rattle or buzz (not every note but sample plenty of regions where people do play)
6). Set intonation
7). play a tune that this instrument is famous for. For example I would play Hendrix on a Strat and John Price on a Martin
8). stretch strings so the show can go on with less fiddling

Point being there is a sequence to my approach and it works great for me.

Height at 12 4th string = The g I set for 5/64th. The e I set for 7/64th. A heavy hitter, five or six string, slack tuning all change these numbers and it's important to know if the player is using drop tuning, beating the thing when they play, etc. All strings between the g and e on a bass get progressively higher as you approach the bass side. Example the A would be 6/64th and the e 7/64th.

Height at 12 1st string = Again I do 5/64th" for a generic acoustic or electric bass, strings, player, etc.

Oris did you build these basses? We love pics and congrats if you did.

Funny, I’ve never been a student chez AAG, but my bass setup is almost identical. I do exchange items 1 and 2. There’s no point in adjusting the TR first if the strings are to be changed to a different model, as very often happens. In that case, one can and should adjust the nut slots with the old strings. Do your FB and fret maintenance, restring with today’s flavour, and only then adjust the neck relief.

Otherwise, our specs are essentially identical. I do find much more variation in bass player setup preferences, compared to electric or acoustics. I have one pro-client for whom we set up her Sadowsky 5-string with only the slightest hint of relief and the same action I might put on a fingerstyle flat-top. She makes it work and looks like the bass plays itself.


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Tim this, what I shared is a generic set-up we tweak as required and even have folks play for us when we are unsure so you're right the player is part of the equation.

I use the old strings to cut the slots but I have the new strings package in front of me and that informs what files I use. We use metal string lifters and that can leave a mark or two on some strings more specifically classical strings so we mark up the crap strings that we are eventually cutting off and pitching and leave the new strings unscathed and factory fresh looking. *I do save bass strings and return to the client, not sure why, no one ever asked me to but I do and that has come in handy when the new strings that the client brought us are the wrong length... That happens from time to time.

With how we cut nut slots only being concerned about the first 3 - 4 frets and how they interact with the slot this works great for us and by cutting the nut slots first it's the only part of the three elements of action adjust that once set you can forget and there is no interaction with the rest, saddles and relief that will change (for the most part there is some with the string height but it's minimal).

With the girls sleeping in after a late night here in Nashville, I'm on a coffee IV drip at a local caffeine dispensary and catching up on email and web traffic. Blessed morning quiet after a raucous evening. Carter and Gruhn Guitars later if I can talk my partners in crime into a musical glow-up .

On acoustic bass setups, I can only offer that they are a bit different in the sense that all of the strings are wound, so the mass per unit of string length is higher, which drives the fundamental and first harmonic string shapes toward what we see on guitar bass strings. In other words, the combination of longer scale and heavier strings means more clearance is needed at the 7th and 12th frets when driving the E1 and A1 in a purely acoustic performance.

This usually resulted in an initial set-up for a 34" scale length 45/105 phosphor bronze strung, four string AGB at Greenridge as follows:

1st Fret Action (E/A/D/G in thousandths): 21/20/19/18
Relief: 0.008" with perfect fret work: 0.010" for fresh factory/builder fretwork; more if the fretwork is excessively worn (or the player routinely channels a Bootsy/Catfish P-F retro vibe)
17th Fret Action (E/G in thousandths): 110/90

If the ABG is closer to the stiffer Tacoma or Asian-sourced factory-made instruments in terms of responsiveness and played unplugged, attack will necessarily be more aggressive to get anything out of E1, so that can drive bass-side action up a little, and relief closer to 0.012". For a responsive ABG with a good onboard pickup system supporting the usual one or two acoustic guitars/guitar and mando/guitar and cajon, a lower setup with a bit less relief - closer to Mr. Breakstone's numbers - would be a good target.

_________________
For the times they are a changin'

- Bob Dylan

I have not seen an acoustic bass in my shop in years that I can think of. They are soooo 90's

I do own one though, my brother gave it to me, and it mostly just hangs on the wall in my studio. I just restrung it about a month ago. My brother, like me, always writes the date on the the old string package and leave it in the case. August 2012 was the last string change. My set up for it was simply, as low as it can go. I found the relief really needed to be on the high side but over all the action is good. When setting up an instrument I always like to ask players what they like and it seems that bass players like low. Those strings are heavy! But acoustic 'anything' needs to have a bit more room doesn't it.

I don't measure height at 1st fret either. I don't think that really has any value and I think it's so difficult to measure that there is too much 'noise.' I just make sure the nut slots are as low as they can go without buzzing on the 1st fret. The 3rd fret rule works here as well. Once the relief is set and the nut is slotted then I mess with the saddle to get the 12th fret action as low as possible. Often times I end up going back and forth a bit.

For me, on a bass, it's as low as you can go but sometimes on older instruments you find it impossible to hit specs without having to do work outside the scope of a normal set up.

And yes please if you built these bass's would love to see pics of construction and finished.

Stewmac offers string height gauges with analog dial indicators for both bass and guitar. Provided the gauge has the correct foot installed and has been modified for reduced spring return pressure, those string height gauges are quite reliable. Same for relief measurement. After a while, with dial gauge readings reinforcing eye, we could get very close by eye alone and the usual manual checks at second fret and 1-body fret.

Greenridge had a small number of customers that were quite capable of sensing a 0.001-0.002 inch change in nut/1st fret & relief setup and a 0.002-0.003 inch change at the saddle, so it was just not an option to go without a bespoke, numbers-driven setup there. Once I had the technique down to handle those customer's Somogyis, Walkers, Traugotts, (and Martins, Yamahas, and Alvarezes!), it was just easier to work everything to that level of repeatability and accuracy. Those tools are expensive, and during the time I was at Greenridge, I replaced those dial gauges at least twice, but ultimately worth it for our customers.

We finally found a replacement dial gauge that held up better than the budget Stewmac article - I think I linked to it in another post.

_________________
For the times they are a changin'

- Bob Dylan

We have clients too that can sense very small changes in the first three fret area and it's not just a feel thing either higher nut slots pull string sharp when fretted.

So we always are a one trick pony with nut slots except for slide guitars we cut them all as low as we can go and that has always satisfied the most picky of the picky that we have as clients. So we never measure anything in the first three frets area we simply cut them as low as we can with a very few exceptions such as mentioned slide and some slack tunings too. We also address the slots second only to the relief and then we never have to touch it again.

I'm still using a Starett 6" engineer's scale on the 64th" side and since we only use it at the 12th it works great for us. Dave uses one too so we communicate this way with an odd combination of fractions and decimals... For example he may as me to do 4.5 and 6 which means treble at the 12th 4.5/64th" and 6/64th" bass side. Weird I know.

Having surgery on my eye in an hour... to remove a cataract even though I told the Doc I prefer Lincoln Continentals... He said I will need readers for close work but my distance will be great again. Oh joy.... hope it all goes well.

Hope your surgery goes well Hesh, had mine done about 10 years ago and it worked out great!

_________________
Steve Smith
"Music is what feelings sound like"

Yes... good luck with the surgery!

_________________
For the times they are a changin'

- Bob Dylan

Hesh, good luck with the surgery!


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Would you mind to share more about this here or I can PM you.


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These HHIP dial indicators seem to hold up in service well, and run about $24 each:

https://www.amazon.com/gp/product/B01BHHXGEG/

The return spring inside the gauge can be removed entirely, or the spring can be resized or replaced with a weaker spring. We did both, but my own gauges are sans springs, and work well. Pop off the back, remove spring, and replace back. I believe we may have received one with a mounting lug on the back, but that can be ground off or hack-sawn and ground, or just pop the back off the dead Stewmac dial gauge being replaced and use that as the new back.

If for some reason the tip of the indicator is lost on the StewMac article when the replacement gauge is swapped in, the kit linked will provide at least a zone ready-to-go or suitable-after-rework tips (points?). I believe Greenridge was still working through a similar kit, when I was last over (I 'borrowed' a tip for my own relief gauge).

https://www.amazon.com/Piece-Electronic-Indicator-Set-inch-Thread/dp/B06XW6K7HH/

_________________
For the times they are a changin'

- Bob Dylan