#1
Many years ago I was given an eight string electric lap steel that has a lot of sentimental value, but I haven't used it much because of problems with tuning intervals.

The country style "close" tunings like C6 don't work well for the style of music I play, folk and blues, but with wider tunings like open D the extra two string gets you into a range that is either too high or too low. I've tried a 7th type tuning which uses intervals of 75754332 semitones, bass to treble, or similar. However, I have a lot of trouble with string interposed between the ones I'm used to, ie the 2nd string in this example.

I've tried re-entrant tunings, where the 8th string is higher pitched than the 7th, and it has it's uses. - You can get a banjo-like effect.

Now I have two double courses on the first and 2nd strings, so the intervals are 7543050 semitones. This gives a nice chimey sound on the two high courses, and adds character.

Any other ideas as to how eight strings can be made to do the work of six?
#2
First of all that E7 is no good. You don't want a 7 at the top like that. E7 should always be xDEG#BE for a 6 with your choice of low string. For an 8, I would go EG#BDEG#BE, although I would suggest nixing the low E and G# and putting an F# in the middle for an E9 and a high G#, so BDEF#G#BEG#. Your other choice is EG#BDF#G#BE for E9.

Really just learn to love C6 or A6 since those are really the most versatile. Maybe C6/A7 which would be C#EGACEG with a high or low A string.

If you really don't want to use C6, you could try a diatonic tuning, CEFGABCE or go with a Bb instead. B11 could also be of interest, ABC#DF#AC#E. It's kind of a half diatonic, half A6 tuning that gives a lot of options. You could also do a bunch of other stuff with the low A if you want, maybe low F#.

Or...

Just leave two strings off?
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#3
Thanks. That second E7 and the C6/A7 look promising, but the problem is I'm getting a bit old to learn new muscle memories for dealing with a string in the middle.

The set up I'm using now is equivalent to six strings in terms of playing. Another I thought about was using an octave pair on the 3rd or 4th string, like Roger McGuinn's 7-string martin, that has on octave pair for the 3rd course - he makes it sound an awful lot like a 12-string.
#4
Wouldn't doubling strings still goof up muscle memory since they're still spaced apart unlike in a legitimate multiple course per string instrument.
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#5
I've modded the nut and bridge so that they are double courses. Very easy, because both are made of soft aluminium alloy. The two string balls share the same anchor hole, and the strings share the same pickup pole piece.

I got the idea from a combination of Big Joe Williams'nine-string and RG's seven-string.
#6
Yeah but doubled strings for steel is gross. You do you expect to slant?
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#8
The problem is that when you slant on doubled string, the bar is slightly farther on one string and so you get that out of tune sound.
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