Re: Difference in experience between 7-string and downtuned 6-string
Can anyone here insightfully compare the difference in experience between both?
Well they are different, like,
totally different from the player's point of view. Not even in the same ballpark. It's a whole different animal really, much like bass, classical or flamenco; the physics are the same but the choreography - not even close.
If you just want to extend the range of power chords available at your fingertips downward by some 5 semitones with minimum disturbance in the upper strings layout, the shortest way to get there is getting a seven. It's just one more string, right?
Then, there are 7 string arpeggio patterns that imply surprisingly regular rhythms in a way that makes notes just fall into the "right" spots all by themselves. Fit players often augment this phenomenon of "notes within reach" with two hand tapping. Shreddy indeed just like Trey and the Gang.
But then from a harmonic point of view, there are (too many) chord voicings that are just a bit too awkward to pull off on a 7 whose neck width hinders thumb-over reach and whose scale length, again, typically doesn't work in your favor when fretting a wide stretch.
As counterintuitive as it might be, the 6 string is more conductive to high polyphony than the 7. To put it bluntly, seven strings suck for chord work; their "built-in six" is the most uncomfortable of sixes so, instead of going bass-ackwards, you are better off developing a whole new style on the seven than trying to adapt six-string-specific licks and finding out you're always a finger short.
Just an opinion, sure but if you want facts, go figure how seven string players embrace means of expression such as single notes, dyads and omitted chord tones - all of which are low-polyphony by definition.
Cowboy chords, on the other hand - being widely voiced triads with some of the chord tones repeated in the upper octave - are fundamental building blocks of the six-string world. Relatively easy to grab on the neck thanks to the strategically placed major third between the second and third string, allowing full-on all-string strums of the picking hand with the minimum of muting. But not on a seven. Once you gain command of CAGED, you're in the game. But not on a seven.
To sum it up, if you have to ask, you may just need both because neither makes up for the other.
Each is going to make you play and compose different things, each could teach you something new because they need a different approach: collective vs selective picking being an example. Point scored for not ignoring the ergonomics of the whole affair since all the practice in the world won't grow you an extra finger. Push your boundaries but do not ignore them.
For blues soloing none of it really matters 'cause it is nothing about numbers.
