Tuning down a step to D9th will give you more low end, but it doesn’t go as low as a standard 6-string guitar. Here’s what the “almost standard” E9th 3+5 changes look like dropped to D.
If you add the “Franklin” pedal, you’ll have a G on the 10th string. That’s close, but no cigar. If you’re like me, you really want that low E and don’t want to give up much to get it.
We can take a real good idea from the 8th and 9th strings of the C6th, which are tuned to A and F. If C6th were tuned D6th, those strings would be B and G. Putting those notes on our 9th and 10th string would mess up our “A” pedal, but it also gets us a step closer to that low E. I’ve read that Buddy Emmons sometimes disconnected that 10th string change anyway.
I have been experimenting with a Desert Rose S-10 4+5. Nice guitar! Before you freak out over the following chart, keep in mind that I have 4 decades of “muscle memory” that I want to retain. My personal quirks include 1) raising the 4th string on LKV instead of a “C” pedal, and 2) I don’t use a 2nd string half-stop. Your reflexes are probably different, and I won’t argue about that. I want to focus on how we can extend the range of the low 2 strings. First, retune strings 9 and 10 to B and G, respectively.
The 9th and 10th strings are now tuned C6th-style to B and G. Notice that the “X” lever change (my p4) is lowering the low G down to E. This is consistent with its use to get a 2 chord from the home position. Nailed it!
The 10th string “A” pedal change is now inverted on the 9th string. I still have the note, but I have to use my LKV to get it. Then I release it as I engage “A+B” to get that iconic 1 to 4 chord change in the low register. Also, the pedals down “A+B” position makes a full G6th tuning G B D E G B D just like a 7-string dobro.
The 9th string change on the “D” lever is also inverted. This is nice: the lever makes octave C notes on strings 2 and 9. It feels a lot like the Bb lever on C6th.
The low F# on the 10th string (my p1) just seemed like a good idea. It has a lot of uses. If you’ve followed me this far, you’ll figure it out.
But if I’ve lost you, here’s a solution that borrows from the U-12: eliminate the 9th string and add a low F# (G# on the U-12).
I don’t like that big interval between the 8th and 9th strings, though. I never warmed up to the U-12 concept for that reason. Thanks for following this to the end. Keep on Steelin’.