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Mivo
06-20-2016, 03:13 AM
I'm trying to determine whether it's risk-free to tune up my Pono baritone by three half-steps.

The instrument's scale length is 20 1/8". The strings I currently use (D'Addario EJ88B) have a total tension of 34.56 lbs when used on a 19" scale (9.15, 9.68, 7.66, 8.07, first to fourth string).

Is there a way to calculate an approximate total tension when I tune these strings up to FBbDG from DGBE? Are the strings likely to handle this well? (Mostly worried about the bridge and the top.)

DownUpDave
06-20-2016, 03:22 AM
You will be fine. Tuning up to Bb on a baritone is something that is commonly done. I have a Pono spruce/mahogany baritone which i have tuned up to Bb with no trouble at all. You will feel the increased tension under your fingers for sure. I currently have it tuned up a full step to my preferred E, A, C#, F# which is nice. Good for strumming with the increased tension taking away the "droning sound" but still retains a nice deep resonant tone.

Additional thoughts. There is a tension chart somewhere on the D'Addario website, a member named "soundboard" has pointed that out to me. You may be able to find it and do the math.

I use the D'Addario titaniums which are a higher tension string in the 2 wounds then the one you use. 17Ibs each as opposed to yours at 10 lbs each.

Mivo
06-20-2016, 03:41 AM
I think I really need to buy strings from Southcoast, if only for peace of mind! :)

I got the idea for the Bb tuning from Dirk. I use re-entrant Bb on my tenor, where it sounds great. Using linear Bb on the baritone would give me the same tuning (easier on my brain), just the linear version. It would make good use of the respective body sizes.

DownUpDave
06-20-2016, 03:46 AM
I think I really need to buy strings from Southcoast, if only for peace of mind! :)

I got the idea for the Bb tuning from Dirk. I use re-entrant Bb on my tenor, where it sounds great. Using linear Bb on the baritone would give me the same tuning (easier on my brain), just the linear version. It would make good use of the respective body sizes.

Good idea. Increasing tension on the strings you have will be very noticable under finger, to the point of uncomfortable. Dirks strings for that tuning will be thinner and the lower tension will feel more "normal" under finger.

Mivo
06-20-2016, 04:36 AM
An alternative to my plan would be to keep the baritone in traditional DGBE and get a DGBE linear set (an octave higher) for my LN soprano from Dirk. That would meet my desire for fewer tunings to juggle, and would have the added benefit that there is plenty of readily usable music available for G tuning.

UkingViking
06-20-2016, 05:12 AM
I am not a string expert, and the others advice is surely more useful.
But math is fun:
I would guess that tuning it up three half-tones will increase the tension by 41%.

If I am not mistaken the frequency is proportional to the square root of the tension.
To tune it up an octave - 12 half tones - you would double the eigen frequency.
That is the same as tuning it up 3 half tones four times in a row. Hence you chance the frequency by a factor 2^(1/4).
To do this the tension needs to go up by the square if this factor, which is 2^(1/2) - the square root of 2, approximately 1.41.

Totally useless information, but fun fact.

kissing
06-20-2016, 05:30 AM
The instrument can handle it, though you may need to adjust the truss rod a bit.

However, it may not be comfortable to play for your hands.

cpmusic
06-20-2016, 05:45 AM
I'm trying to determine whether it's risk-free to tune up my Pono baritone by three half-steps.

If you're using the stock strings, you might contact the folks at Pono to ask if the uke can carry the extra tension.

But why wouldn't you just use a capo? I know that would shorten the effective scale, but it would alleviate any problems you might encounter with tension on the instrument and on your fingers.

kissing
06-20-2016, 05:51 AM
If you're using the stock strings, you might contact the folks at Pono to ask if the uke can carry the extra tension.

But why wouldn't you just use a capo? I know that would shorten the effective scale, but it would alleviate any problems you might encounter with tension on the instrument and on your fingers.

I'm not Pono, but the Pono Tenors and Baritones have a truss rod and can handle the tension of 3 half steps very easily (and more).

Mivo
06-20-2016, 06:25 AM
Hm, the B string is pretty taunt without tuning it up. Kind of concerned that it might snap if I try. I'll probably just go ahead and order a set of Southcoast strings. No instant gratification, though.

cpmusic
06-20-2016, 10:48 AM
I'm not Pono, but the Pono Tenors and Baritones have a truss rod and can handle the tension of 3 half steps very easily (and more).

That would be my guess, too, but I'm also thinking about the bridge and the top. Even if neither is damaged, too much tension can overdrive the top, resulting in a muted sound.