3/4 and 4/4 strings same length?

[calliopeguy]

I have two question: one, on a 3/4 bass, what is the actual total length of each of the four strings? Two, can I use 4/4 strings on a 3/4 bass? I believe the string length is usually measured from nut to bridge but I'm curious about the total length. Obviously I don't have much experience with an upright bass but just curious.
Thanks
Ken

[lhoward]

There can be a variance of string length for what is called 3/4 and 4/4, but Thomastik-Infeld gives a 3/4 length string as 104 - 106 cm. And yes, that's measured from the nut to the bridge. They list a 4/4 string length as 110 cm. I would think you could use a 4/4 string on a 3/4 instrument, but the string tension would be less than that for a 3/4 designed string. Depending on your setup and playing style, it could be workable or be a disappointment.

I personally would not use a string intended for use on a bass with a 4/4 string length on a 3/4. They're usually more expensive and, to make a general statement, I don't think it would sound as good (focused, clear) as it would with a correct length string. I could be wrong now, but I don't think so (after the Monk theme).

Lloyd Howard

[dchan]

Generally, I don't think it's a good idea to use 4/4 strings on a 3/4 bass.

But then again, everyone seems to be using S42 Spirocores, which are actually made for 4/4 basses.

[Bassism]

Depending on the string, wrapping the thicker part of the string around the roller on the tuning machine can damage it and lead to premature breakage.

[billyfalconer]

Originally Posted by calliopeguy

I have two question: one, on a 3/4 bass, what is the actual total length of each of the four strings? Two, can I use 4/4 strings on a 3/4 bass? I believe the string length is usually measured from nut to bridge but I'm curious about the total length. Obviously I don't have much experience with an upright bass but just curious.
Thanks
Ken

There's only an inch or two difference, if any, between a 4/4 and 3/4 mensur. As in 40" vs 42" max. Some 4/4 basses, like Arvi's, have the same string length as a 3/4. When there's several inches extra of wrap on strings, I'm surprised there would ever be any problem.

[drurb]

Originally Posted by lhoward

I would think you could use a 4/4 string on a 3/4 instrument, but the string tension would be less than that for a 3/4 designed string.

Why? Are they not the same string except longer? In that case, you'd just have extra string wrapped around the tuning roller which, as mentioned already, is a bad idea.

[lhoward]

Originally Posted by drurb

Why? Are they not the same string except longer? In that case, you'd just have extra string wrapped around the tuning roller which, as mentioned already, is a bad idea.

The 'why' has to do with the characteristics of a vibrating string. In order for the note to be the same for a shorter string of the same mass per unit length, the tension on the string must be reduced. Ex: if you were to play an "A" on the A-string (open A), it would be vibrating at 55 Hz (based on the international definition of "A" being 440 Hz, only three octaves lower for the open "A" on a double bass).

In order to play an "A" up the neck, say in the half or first position with the index or middle finger, you have to de-tune the open A-string by however many half tones you are up the neck. So for a shorter string length (nut or finger to bridge), the tension is reduced to play the same note as compared to a longer string of the same mass per unit length. Considering that a 4/4 string is meant to be tuned to its design note at a certain design tension for a string length of 110cm (using TI Spirocore 4/4 mediums in this example), then putting it on a 3/4 bass of 106cm string length would require that the string tension is reduced below what its design tension is, which is the basis for my quoted statement and why I stated it may not sound as good. But in a practical sense, it may not matter that much since double bass strings are 'flat wound' and have less overtone content than a comparable round-wound would have (if they existed). Comparing flat and round-wound strings for EBG confirms that assumption.

As the string length to diameter ratio decreases, the less well defined the sound is due to loss of overtones. A 3/4 string used on a 3/4 bass will be tuned to its design note at the design tension and, for all practical purposes, sound better. Obviously, putting a 3/4 string on a 4/4 bass would be a no-no as it would require the string to be tuned to a tension higher than its design tension in order to tune the string to its design note and would probably shorten the life of the string due to being stretched beyond what the design tolerance intended. And this does not consider what it would do to the sound. Also, whether the bass could handle the extra tension from a whole set of strings is another issue.

The problem of having extra string wrapped around the peg, as you mentioned, is really a separate issue than what I was commenting on.

Lloyd Howard

[drurb]

Doh! Of course! Thanks for the reply. I should have realized that. I have two things to add. In your example, when you hold down the string in half or first position, you have just increased the tension slightly. I do understand, though. In order to keep tension constant as length changes, so must mass.

By the way, some string manufacturers don't trade off like this between their 3/4 and 4/4 strings although, by all rights, they should!

Thanks again.