To clear up some possible confusion due to incomplete descriptions.
The Hohner 364 and 365 Marine Band models are tuned the same as the regular 1896 models, with the addition of 2 extra holes on the 364, and four additional holes on the 365.
IN G, the 364 and 365 in G have the same bottom note as the regular G.
IN C, the 364 and 364 in C are an octave LOWER. than the regular C. This makes for a very cool low C harp.
The top register is also interesting, as it gives rise to some really wild high blow bends. Because the blow and draw notes are tuned so far apart in these holes, the notes can be bent really far.
These things are covered in some detain in HIP No. 2.
The SBS harps, by contrast, start out with three EXTRA holes BELOW the regular 1896 tuning, and resume normal tuning in Hole 4. Here are respective tunings for 1896, 365, and SBS for C:
REGULAR 1896 Marine Band in C:
__1___2___3___4___5___6___7___8___9___10_ DRAW | D | G | B | D | F | A | B | D | F | A | ========================================= BLOW | C | E | G | C | E | G | C | E | G | C | ----------------------------------------- | | SBS in C: | | | | __1___2___3_|_4___5___6___7___8___9___10__11__12__13|_14_ DRAW | D | G | B | D | G | B | D | F | A | B | D | F | A | B | ========================================================= BLOW | C | E | G | C | E | G | C | E | G | C | E | G | C | E | ---------------------------------------------------------
(hole 14 on the SBS is a sometime thing - on some instruments it works, and on others it doesn't. It's x'd out in the official tuning diagram)
364, 365 in C (364 ends at Hole 12)
__1___2___3___4___5___6___7___8___9___10__11__12__13__14_ DRAW | D | G | B | D | F | A | B | D | F | A | B | D | F | A | ========================================================= BLOW | C | E | G | C | E | G | C | E | G | C | E | G | C | E | ---------------------------------------------------------
So, on a 365, the tuning in HOles 1 -10 is the same, just an octave lower on a C.
On an SBS, regular tuning doesn't start until Hole 4. Holes 1 - 3 are an extra "basement," like the regular holes 1 - 4 added on an octave lower.
On the low C SBS, you get regular range plus a basement. Same is true for D and F keys.
On G and A, the basement is the regular range. Above that you get a high G harp and a high A harp.
Again, the SBS is covered in some depth in HIP No. 3 and the demonstrated on the optional accompanying cassette.
There are also some LOW G and LOW A SBS's kicking around. I have a low G - it's a gas. They were originally made by mistake, and from time to time Hohner will make a batch on request - in minimum sold lots of 200. Norman Ives in England (who also handles HIP subscriptions over there) sometimes has them available.