Guitars that sound better with Capos. Could it be the nut, voicing, or imagination?

[vibrolucky]

A little background: Starting 25 years ago, I sacrificed other things in life and was able to purchase some nice vintage instruments.

49' Gibson J-45
56' Gibson J-50
65' Martin D-28
80' Martin D-41

Like owning classic cars, I've never hesitated to pay the best luthiers I could seek out for maintenance/repairs. Of course there is pride of ownership, but I've always seen myself as a caretaker for these as well with a genuine appreciation for keeping things original and trying not to neglect them or do anything crazy that would hurt the originality.

Issue at hand: The two Gibsons mentioned previously are very similar tonally and with playability, with one exception. Recently (last year or so) I've noticed a peculiar tone from the Gibson J-50 on the high B and E strings sounding 'tinny' and weaker than it used to be. I've tried changing strings of course, experimented with different bridge pins, etc. But when I use a capo the issue immediately stops and the voicing is strong again.

The older I've become (age 50) the more I'm using capos for songs as my voice can't hit high registers, and it seems as my musical taste evolves more songs I like are capo'd now.

So back to the J-50, it definitely sounds louder and more articulate capo'd between frets 2-4. Could be my imagination, or an issue with general setup, nut (original) or got me thinking maybe some guitars just sound sweeter in that register?

The J-50 is a little overdue for a re-fret, and I was thinking of going with some slightly taller frets which will require a new nut most likely. So it will be interesting to see if it (A) fixes the 'tinny' sound I've been experiencing, as well as the open string/capo thing.

I've heard other players comment about their instruments having a 'sweet spot' of capo 2-4 as well, hard to tell if its mind games or reality.

Your thoughts?

[Alan Carruth]

I'd check the nut first.

In theory putting on a capo alters the 'characteristic impedance' of the strings, if I understand that correctly. This could change the way the strings pass energy into the top.The effect would be frequency dependent; if you capo up do you get the same effect on those notes on the B and G strings? You could also try capoing up and tuning down, which might isolate the nut effect, if there is one.

[tadol]

I think what you hear with a capo is the strings breaking over the top of a steel bar, rather than a bone or plastic channel. It’s like a zero-fret guitar in that way. Also, there is no string to absorb any energy between the fret and the capo, while there can be a few inches if string at the nut. Finally, we do hear higher pitches more crisply. So, it’s not imagination, but I can’t say what it specifically is -