660 vs 670 scale length

Trovador98 · June 29

Consider this:

Two Selmer style D-hole guitars made from solid walnut back and sides, spruce top, typical body dimensions, but one made at a medium 660mm and another long 670mm scale length.

Ergonomics aside, what are some pros and cons of each guitar?

JasonS · June 30

That's not even half an inch so not really a meaningful difference. I would just go with whichever one I like better.

MichaelHorowitz · June 30

Generally shorter scale lengths will decrease string tension resulting in easier playability and fuller mids/bass. Longer scale lengths will have more string tension which will require greater strength/technique to play but will have greater projection, especially in the high end.

Of course, there are many other variables like action, string gauge, neck angle, body size, top thickness, etc which can effect the result. Some great luthiers like Hahl or Dupont can manage all these variables to produce short scale guitars that still have great lead projection while others sound pretty flubby and only useful for rhythm.

pdg · June 30

Just to clarify, 660mm is not really "short"scale. 12-fret D-holes are typically and traditionally 640mm scale. So 660mm will have a slight difference from 670mm, but should still be closer to 670mm than the short-scale D-holes.

D-holes generally have less cutting power, so if you want the most cut and closest to "stinging" trebles of oval holes, the 670mm would be the best bet, though the 660mm guitar may be a bit more versatile. Also, 670mm is more standard, in case you decide at some point to sell it.

CraigHensley · July 2

I find the pros of 660 far outweigh the cons. The string tension is perfect and more comfortable than 670 without sacrificing tone. In fact, I like the added bass and mids, it's easier on the ears. I've owned 12 gypsy guitars with the longer scale lengths and sold them all. Keep in mind the standard Martin/Fender scale length is approx 645mm, so even a 660 scale is considered a long scale compared to the common western guitar.

Also, something no one's mentioned about 670, they seem to suffer more from sympathetic feedback notes. I'm not sure why these guitars buzz for no reason, but it seems totally acceptable that they have subtle acoustic feedback resonance that will rattle notes for no fixable explanation. Most people don't mind this vibe as it seems to be part of the music, but I find it irritable and distracting as a player. The decreased tension on a 660 seems to alleviate this phenomenon.

Craig Bumgarner's Corazon models are all 660 and there's plenty of players who excel on these instruments.

Buco · July 2

@CraigHensley you made me want to have a 660mm scale guitar with that line of thinking.

Trovador98 · July 8

@CraigHensley Really helpful feedback. I’m talking to Cyril Gaffiero about a possible build and he seems to favor the 660 for the playability. I shared your comment about your experience with sympathetic feedback/buzz and at 670 was surprised to hear it. I like the idea of a versatile guitar as I tend to write solo acoustic pieces and don’t (yet) play proper GJ.

Trovador98 · July 8

https://www.djangobooks.com/forum/discussion/comment/125649#Comment_125649

@pdg haha yeah I agree which is why I called 660 a “‘medium” scale in my original post.

What about 660 with 11s vs 670 with 10s?

I’d imagine these differences start to get very subtle.

CraigHensley · July 9

Maybe @paulmcevoy75 can pipe in about feedback notes on gypsy jazz guitars to clarify. He could explain it better than me as he's an experienced builder of fine instruments, and I recall him mentioning it a couple years ago in his shop.

paulmcevoy75 · July 10

https://www.djangobooks.com/forum/discussion/comment/125704#Comment_125704

I don't have a lot to say tbh. I have only made 670mm guitars and I like them. I have fairly large hands, I guess. But it seems like people of all sizes play these guitars and I think having things set up really well can make a huge difference. Ultimately a lot of guitars that people play are set up pretty badly and people end up compensating for that with their hands and you may end up squeezing a lot or doing other weird stuff.

I haven't played a lot of short scale gypsy guitars though so I don't really have an opinion. For classicals 650 is the Segovia standard but I like 640 just as much.

I like 10s on my instruments though.

I honestly don't know about any particular buzzing issues related to scale length. A shorter scale instrument should buzz more, theoretically, because the strings are loser. But for the most part, instruments shouldn't buzz unless you make them buzz. Really good instruments usually are up against the wolf note spectrum which happens with sensitive and powerful instruments but I don't think scale length would change that.

Talking out my butt here mostly.