Unison or Octave pairs on G and D strings

[timacn]

I've been asking lots of questions here lately. Here are two more:

I should probably know the answer to these questions but I don't.

On an octave mandolin, do most people tune the G and D strings in unison or octave tuning? Also: do most people string the higher string of each course so that the higher string gets hit first on the downward strum?

As always, thanks to all for your help.

[mandobassman]

I think it can be done either way. I believe that, in the purist sense, the octave mandolin is generally tuned as unison strings. It is supposed to be the lower octave version of the regular mandolin, but many people use different tunings and use octave pairs. The octave strings can create a different sound. Personally, I would only use the octave strings if I were only playing rhythm. I don't think the octave strings sound very good when playing lead notes. If you do use octave pairs, I would think you would have the higher octave string on top (same as a 12-string guitar).

[Charlieshafer]

Pretty much what Larry says; I use exclusively unison pairs. The idea for me is that if you're using an instrument tuned to a lower register, take advantage of the lower notes. Otherwise, it's just this wishy-washy nowhere land...

[jmp]

I believe most people tune OM in unison, including myself.

[allenhopkins]

Well, octave mandolin strings come packaged for "unison" tuning, and most octave mandolin nuts and bridges are set up the same way. So I'd guess that's the "standard."

I have put my Octofone into "octave" tuning on the 3rd and 4th courses, with the thinner string "uppermost" when I strum it -- like a 12-string guitar. I love the full chord sounds, but do notice that the octave tuning sounds a bit muddier when I'm playing single-string melodies. My Flatiron 3K OM is in "unison" tuning.

Greek bouzouki tuning, as I understand, has "octave" tuning on the lower-pitched courses.

[Mandobart]

Once again, here is my 20" Tom Jessen OM with octave pairs. I use the "regular" string as the lowest (first one you hit on a downstroke) which is opposite of how a 12-string guitar is strung. I really like the octave pair sound.



and here is my mandocello, done the same way:

[zoukboy]

Tim: most octave mando players that I have met use unison pairs on the G and D courses. In fact, most Irish bouzouki players do the same. There are a few exceptions, myself included, who use octave pairs, and sometimes on just the G course (me). My personal preference is to put the higher of the two strings on the lower side of the pair (so the lower octave string is plucked first on a downstroke). Greek bouzoukis have octave stringing on the low C and F courses (or the low D course on a three course bouzouki).

What it all boils down to is what you like. If your octave is set up for unisons it's no problem to try octave pairs: simply replace one string in each of the bass pairs with another string that is 1/2 the gauge.

Good luck!

[chubakkah]

After listening back and forth to some Tim O'Brien and Sarah Jarosz stuff, I have the G and D in octaves. Tim is lucky enough to have 2...one in octaves and one in unison. So far, I really like the sound. Fletcher build the nut so that I could change back and forth if I wanted to, but I haven't made the switch yet.

[Linds]

When Fletcher built mine, I had it done with the G and D in octaves, as well, with the lower string struck first in the downstroke. It gives the sound a kind of sparkle that I really like. Unfortunately, I don't think I can switch to unison strings, but I've found that I don't have a lot of problem playing melodies. I simply "miss" the higher string. You can do some nifty things with the higher string on solos that would otherwise require more of a stretch to fret the note.

[garrison]

I recall a thread about octave tunings for short scale OM's. They said matching intonation of the octave strings could be a problem. Personally I don't know. But if this is true, you might want to consider scale length before changing over. Can anyone give any input on this?

[Charlieshafer]

Well, the fact that you have different string gauges means you automatically have different string tensions. This automatically means when you push down on the pair, you'll automatically need enough pressure to keep the lower, heavier gauge string from buzzing, which automatically means the thinner, higher string will be automatically be deflected just a tiny bit more, increasing the pitch just a little bit. If you have really good ears, the difference will haunt you to the grave, like finger nails on a blackboard, endless in it's drive to push you over the brink to insanity. OK, maybe that's a little harsh, but yes, intonation problems while small, are very difficult to overcome.

[allenhopkins]

If you want an even more extreme example of what Charlieshafer's saying, try playing a tiple. The combination of very short scale and "octaved" strings make tuning and playing an endless exercise in compromise.

[BradKlein]

Here, Sarah Jarosz seems to be playing with octave strings south of the G and D - opposite of how most 12 strings guitars are strung. I suppose that if one exclusively strummed chords, it might be preferable to reverse those - and I imagine that since SJ plays melodic lines and runs on those strings, she finds it preferable to string it as she has.

[Jayyj]

Here, Sarah Jarosz seems to be playing with octave strings south of the G and D - opposite of how most 12 strings guitars are strung. I suppose that if one exclusively strummed chords, it might be preferable to reverse those - and I imagine that since SJ plays melodic lines and runs on those strings, she finds it preferable to string it as she has.

What a beautiful version of that song!

Just to be awkward, I tune one of my OMs in octaves on the G and D and the other as a C-G-D-A tenor - just prefer the way they sound.

[zoukboy]

Well, the fact that you have different string gauges means you automatically have different string tensions. This automatically means when you push down on the pair, you'll automatically need enough pressure to keep the lower, heavier gauge string from buzzing, which automatically means the thinner, higher string will be automatically be deflected just a tiny bit more, increasing the pitch just a little bit. If you have really good ears, the difference will haunt you to the grave, like finger nails on a blackboard, endless in it's drive to push you over the brink to insanity. OK, maybe that's a little harsh, but yes, intonation problems while small, are very difficult to overcome.

Tension is not automatically different because of different gauges. As long as the frequency is double and the mass is halved for the higher string then the tension is the same. In fact a good way to try switching from unison to octave pairs is to replace one string in a pair with another string that is 1/2 the gauge of the original.

As someone who has played octave stringing professionally for many years I can attest to the fact that intonation can be a challenge, BUT, if you decide to live with octave bass pairs a good tech can intonate the bridge accurately to compensate for the difference in gauge within the pair. See this photo of a properly intonated Irish bouzouki bridge:

The lower-tuned strings in the pair have to come off the bridge further back on the bridge to compensate for their greater thickness. Not that hard to overcome, really, but one has to make a commitment to playing in octave pairs to make the change worthwhile.

[Charlieshafer]

Yes, technically you can get the tension the same, but the force required for deflection changes due to the different diameters of the strings. Larger diameters are stiffer inherently than thinner ones. And while measurable tension may be the same, different strings in either materials or structure (wire vs. wound with core) are going to have different elasticity. All that contributes to the intonation issue. I didn't say it was a huge difference between the strings in intonation, but it did exist. That shouldn't stop anyone from using unison pairs, it's just a factor of physics.

[Leigh Coates]

I string my octave mandolin in unison.

I was considering having my new bouzouki strung in octave pairs, but now I'm not sure. I may have it in unison, as I like the bass to be deep-ish, and I'm also worried about the chords not being "true" all the way up the neck if it were tuned in octaves.

[zoukboy]

Yes, technically you can get the tension the same, but the force required for deflection changes due to the different diameters of the strings. Larger diameters are stiffer inherently than thinner ones.

With larger diameter wound strings stiffness is usually due to the diameter of the core rather than the overall gauge of the string. Have you ever noticed the difference in stiffness between, say, a plain steel .020 and a bronze or nickel wound string of the same gauge tuned to the same pitch? The plain string is MUCH stiffer because it is much heavier than the core of the wound string.

I think what you are talking about is perceived differences rather than measurable differences. With an octave pair that has both a wound and plain strings the higher plain string might be stiffer. In an octave pair in which both strings are wound the lower string might seem stiffer. I have experience both and tweak gauges accordingly.

Also, the 2/1 difference in string gauge for an octave pair means that when both are fretted the tops of the strings are uneven and that is certainly perceivable by a player. It takes careful left hand technique to accurately fret an octave pair without buzzing or tuning distortion. Intonating the bridge or saddle as shown above certainly helps mitigate that but it is dependent on technique, too. It also limits the types of capos that will work. Some capos with a hard material that contacts the strings don't work as well with octave pairs as unisons because the harder material will not fret the thinner octave strings effectively.

[zoukboy]

Leigh: see my post above. It is possible to have true intonation with octave pairs but you must have the bridge/saddle compensated especially for octaves. If your bouzouki has a one piece solid bridge you might consider asking the builder to make another that is compensated for octaves. If it has a separate saddle and bridge then an alternative saddle might could be made.

[michaelpthompson]

I was considering having my new bouzouki strung in octave pairs, but now I'm not sure. I may have it in unison, as I like the bass to be deep-ish, and I'm also worried about the chords not being "true" all the way up the neck if it were tuned in octaves.

From what I understand, bouzoukis are often strung with at least a couple of octave courses, so they're probably designed to compensate for it, while octave mandolins are traditionally strung in unison and would need some modification for octave pairs. You might also experiment with having the lower string being struck first to see if that enhances the bass sound you're looking for. Twelve-string guitars can sometimes sound a bit "jangly" because of the higher note being struck first.

[Jim Yates]

It can get a bit confusing when different folks have different ways of describing things. There are the folks who use gravity, that is "down the neck"means closer to the bridge, "the high strings" or "the top strings" mean the G course, while the "bottom" or "lowest" strings are the E course.
Then there are those who use pitch to describe things. They say "up the neck" and mean closer to the bridge. They call the E the "high" or "top" string and the G is the "low" or "bottom" string.
Both methods make sense if we know what the person is talking about, but they are confusing if some folks use gravity (distance from the floor) and some use use pitch.
This becomes even more confusing when we talk about octave strings or re-entrant tuning.