Question with intonation regarding drop tuning

[EssJay]

I'm currently just waiting on a set of flatwounds to arrive in the mail for my fretless 4 string and I'm gonna be taking it into the shop to get it set up once they arrive. I'm looking to get the bass set up for D standard (DGCF) tuning and lately I've been using alot of drop C tuning, my question is that if I get it set up for D and tune it down to drop c will the intonation be off by very much?

[XylemBassGuitar]

It depends on the bass, strings, scale length, action and probably many other factors that aren't coming to mind at the moment.

In theory, yes, your intonation will be off if the bass is set up for drop D and you tune it down to drop C. As you go up the fretboard in drop C, the intonation will go slightly sharp as looser strings will stretch more readily when fretted, thus raising their pitch. The Drop C tuning would require more compensation at the saddles than the drop D tuning.

In reality, you might not notice the intonation to be off at all. It depends on how good your ear is and other factors of your bass' setup and construction. Maybe someone else on the forum has real-world experience with this and could say how thier intonation is affected with drop-tuning.

If not, try it out and see what happens.

[Turnaround]

Originally Posted by EssJay

....my question is that if I get it set up for D and tune it down to drop c will the intonation be off by very much?

In a word, NOPE. In theory there will be a difference in intonation. In practice, I defy your audience to hear the discrepancy. And you probably won't notice the difference unless you have exceedingly good hearing. Here's the details...

First let me say that this won't make much sense unless you are accustomed to tuning by the beats produced close-but-different frequencies.

The difference between C and D on the bass is 4 cycles per second. If you sound those two notes together you will hear 4 beats per second and the two notes will definitely sound out of tune.

Now with a standard scale length, the difference in tension on the string between the two notes in question is about 2pounds. Since the tension of the low string at D tuning is about 14 pounds, the reduction in tension is about 15%. So the resultant frequency would vary about 15%. Applying that to the difference in frequency, you end up with 15% of 4 beats per second or 1 beat every .6 seconds. The effect on intonation is going to be a small fraction of this. Normal intonation compensates for the variation in tension caused by fretting a string and these are in the range of a few cents in this frequency range. A "cent" is one hundredth of a semitone, so in our case we are talking about a few hundredths of the amount we have arrived at so far. Saying that the intonation difference is worst-case 10 cents, when we apply that to the calculations, it means a sonic difference that will produce 1 beat every 6 seconds... worst case!

I certainly would have difficulty detecting that. My strobe tuner would too. So, will the intonation be off? - Theoretically, yes. In practice? Not on this planet.

[Jactap]

One word. Fretless.

[EssJay]

Ok, thanks for the answers guys, although I'm not sure if I'm missing something very important to Jactap's reply though, as it seems rather unhelpful to me.
Turnaround, your answer was quite helpful, thanks alot man.

[thirtypoint87]

Originally Posted by Turnaround

In a word, NOPE. In theory there will be a difference in intonation. In practice, I defy your audience to hear the discrepancy. And you probably won't notice the difference unless you have exceedingly good hearing. Here's the details...

First let me say that this won't make much sense unless you are accustomed to tuning by the beats produced close-but-different frequencies.

The difference between C and D on the bass is 4 cycles per second. If you sound those two notes together you will hear 4 beats per second and the two notes will definitely sound out of tune.

Now with a standard scale length, the difference in tension on the string between the two notes in question is about 2pounds. Since the tension of the low string at D tuning is about 14 pounds, the reduction in tension is about 15%. So the resultant frequency would vary about 15%. Applying that to the difference in frequency, you end up with 15% of 4 beats per second or 1 beat every .6 seconds. The effect on intonation is going to be a small fraction of this. Normal intonation compensates for the variation in tension caused by fretting a string and these are in the range of a few cents in this frequency range. A "cent" is one hundredth of a semitone, so in our case we are talking about a few hundredths of the amount we have arrived at so far. Saying that the intonation difference is worst-case 10 cents, when we apply that to the calculations, it means a sonic difference that will produce 1 beat every 6 seconds... worst case!

I certainly would have difficulty detecting that. My strobe tuner would too. So, will the intonation be off? - Theoretically, yes. In practice? Not on this planet.

Wow... that was great. I was getting ready to throw down the science here but I see that um..... you've just done a better job at it that I would have!

[Turnaround]

Originally Posted by EssJay

Turnaround, your answer was quite helpful, thanks alot man.

I'm glad you found it helpful and not just pedantic. I think I got carried away in the analysis.

[202dy]

Well said.

Bless the pedants.

[Joshua]

Originally Posted by 202dy

Well said.

Bless the pedants.

Amen on both counts.

[svenbass]

Originally Posted by EssJay

Ok, thanks for the answers guys, although I'm not sure if I'm missing something very important to Jactap's reply though, as it seems rather unhelpful to me.

I think what he meant was that regardless of any intonation issues, with a fretless instrument you should be able to play the correct pitch. With a fretted instrument you are restricted because of said fret, to the out of tune note.

[Solarmist]

No - you won't even notice.