Nylon Strings - The Physics of Temperature and Tuning

[2-5Guy]

I purchased my first nylon string guitar a couple weeks ago which is a Sadowsky Electric Nylon. Actually, this specific S/N guitar is the one that was reviewed by Jazz Guitar Today online magazine recently. Beautiful guitar. No doubt about it. This will be my seventh Sadowsky so I'm no stranger to Roger's impeccable work.

Having said that, I'm a newbie to the world of nylon strings and have a question/observation. I know nylon strings tend to be more sensitive to steel with regards to temperature/tuning. Last night I noticed that the second string (B) kept going sharp on me. After a while it settled down as I was waiting for the temperature in my home studio to come up. Been a bit cold here in Southern Oregon lately. Now, I can fully understand why nylon will loosen up and decrease in tension as the air warms and going flat, but in this case it seemed to be increasing going sharp. And ONLY the B string.
This all points to the particular string but the physics behind it is what's got me perplexed.

EDIT: I think I figured this out after typing all of this. It was probably still reacting to the cold in the room when I took it out of the case before it could warm up again and equalize.

[Oscar67]

I’m not aware of nylon responding to temp changes. If it did, I’d expect all three of them to go sharp. Your B string going sharp might indicate that there’s friction at the nut and/or the bridge. It happens, even on very good guitars. Try some graphite from a pencil and see if it helps.

[Rob MacKillop]

Congratulations on the new acquisition!

Nylon strings are certainly very different in many respects to steel strings, and will take a little time to get used to. You can stretch them out a bit every day for a week, then they should settle. But they will never settle for a prolonged time.

There are also many brands to choose from, with many production differences as well as materials, not to mention tensions. With every new nylon-strung guitar I get, there is a period of testing different strings to find what suits it best.

Have fun!

[2-5Guy]

Good point.
I will try a little Big Bends at the witness points. Thanks.

[2-5Guy]

And here's the reason for me getting this guitar.

[Doctor Jeff]

I knew a guy who upgrade from a Godin NS to the Sadowsky. Beautiful tone and workmanship for sure.

There is always a period of time of break in for the strings. Some require more stretching than others. The thought about binding at the nut is good too. (I hate it when that happens, ouch…)

FWIW I put some Bella 900B Elites on my Cordoba Stage (poor man’s Sadowsky) months ago, and after the first 2 weeks it has barely required retuning. Much more stable than any of my other guitars. (Probably the thick poly finish LOL—completely immune to humidity…) Also, no major decrease in brightness, although admittedly I’m not interested in a super bright tone for what I play.

I like the Bellas better than any other nylon strings I’ve used recently. And LOVE the look of them—black nylon with gold wound strings. Very classy.

[2-5Guy]

Enclosed with the guitar was a document stating that Roger experimented with several strings during the development of his Electric Nylon and found these to work the best for this model. FWIW:

SETS - LA CLASSIQUE™ SMOOTHWOUND - GHS Strings

[Jimmy Mack]

Tell me about it!

Got a great Classical guitar, but the string thing !!!!!

Some expensive strings do not justify their expense.

[yebdox]

Caution: I played an outdoor gig a couple of summers ago and thought it would be fun to take my Godin along to augment my 175. Even though we were not necessarily playing in full sun, ambient temps were probably in the upper 70's/lower 80's and the thing kept going flat within minutes of tuning... probably lost a repeat gig because of that, and I will definitely not try that outdoors again, at least when it matters.

[darkwaters]

Yep, sounds like the string is binding in the nut slot. An investment in the appropriate nut files might not be a bad idea. Also, I’ve come to realize that new guitars tend to have the nut slots cut too high. Having the nut slots cut to the right height (Not too low!) really improves playability. If you do decide to go this route, make sure to set the relief and action properly first! How do I know this? Don’t ask.

As for nylon strings going flat all the time, there’s an old saying amongst Classical guitarists that when the guitar stays in tune, it’s time to change the strings. I’ve found this to be true.

[Dave70]

Nylon treble strings go sharp with heat and flat with cold.

[2-5Guy]

Nylon treble strings go sharp with heat and flat with cold.

That's exactly what's going on.
After spending more time with it last night, I found that all three (E,B,G) were creeping up sharp after taking the guitar from a cool case to a warmer room. After about an hour it stabilized. This is something new to me and counterintuitive to my logic.
Thanks for the clarification!!

Oh and here's a couple of pics of it.
Jazz Guitar Today magazine had just reviewed it and sent it back to Roger.
I was lucky enough to call at just the right time when inquiring about any in the works. So naturally I grabbed it.

[RJVB]

Nylon is also hygroscopic, AND just playing them will heat them up internally just enough so they go sharp noticeably.

The settling process mentioned above is due to stretching which of course means they continue to go flat as long as they're not settled. This also causes them to be stretched thinner (the unit density doesn't change) which means that the actual working tension is lower than the one indicated (if the brand gives such an indication).

In practice it means I rarely tune before I've completed the part of my own warm-up routine that doesn't involve anything where intonation is important (I always start with RH finger exercises on open strings for that reason).

FWIW, I never noticed that steel strings behave in a really different way; they too seem to go sharp when the ambient and instrument temperature rise.

[2-5Guy]

Nylon is also hygroscopic, AND just playing them will heat them up internally just enough so they go sharp noticeably.

The settling process mentioned above is due to stretching which of course means they continue to go flat as long as they're not settled. This also causes them to be stretched thinner (the unit density doesn't change) which means that the actual working tension is lower than the one indicated (if the brand gives such an indication).

In practice it means I rarely tune before I've completed the part of my own warm-up routine that doesn't involve anything where intonation is important (I always start with RH finger exercises on open strings for that reason).

FWIW, I never noticed that steel strings behave in a really different way; they too seem to go sharp when the ambient and instrument temperature rise.

Is the reason why nylon is a challenge for intonation because of the low tension compared to steel?

[RJVB]

Is the reason why nylon is a challenge for intonation because of the low tension compared to steel?

Not certain what challenge you mean TBH. You could also argue they're less of a challenge because they stretch more easily and thus are more forgiving to things like pressing too hard or the lowest fret intonating audibly sharp when the open string is in tune and action at the nut a little too high.