Ok, I love tinkering with gear, and so I am hoping I can get a little educated here. I am helping my brother in law with like a "djent-step" side project as a bassist. now, the "genre" yuck aside, i have been looking into alternate tunings. so, here is the basic idea:

inspired initially by the original warwick vampyire NT tuned to F#, and by meshuggah. i was wondering (and if there is a good thread on this already, ill go there) what i need to consider (beyond adjsuting the truss rod and the nut) to tune a bass from F# to E. The bass is a 5 String F Series ESP LTD, and so snagging a F# string from Warwick, i want to tune the bass to EADGB, except down, not up.

i am not schooled in any of the theory about frequency or anything, and im gonna run it through an ampeg 100w combo (not sure if that is good enough to record with honestly either). i know it is alot of questions packaged in one overall question, but i am really open to any information on this. I play a 5 string normally, and tuned to A once, but I really like standard tuning on my 5 string. so yeah, don't hate me or anything, im just curious if this path is sonically workable. ive been listening to some pretty heavy stuff lately for inspiration, but i don't know what those type of bands use gear wise.
So, if I'm reading that right you're actually tuning an octave below a normal bass?

With reference to http://www.seventhstring.com/resources/notefrequencies.html that would be E=20.6Hz, which is lower than the bottom note on a piano.

According to vibration theory, and what we all know about how guitars work, we can make a note lower by three methods: increasing the length of the string, increasing the mass (gauge) of the string or reducing the tension. If you're interested in the actual maths there's a good reference here: http://www.school-for-champions.com/science/sound_from_string_equation.htm

Obviously we can't make the string any longer so we're stuck with heavier strings and lower tension. The reference above gives us some interesting metrics about the effects of changing mass and tension - in short they both affect the pitch by a factor of 2:1.414 - so we could spend some time calculating a solution.

Fortunately, as is often the case on the internet, someone's already done the hard work for us: http://www.stringbusters.com/stringfaqs.asp
On that page you'll find a tension and gauge calculator. Plugging in the numbers, there are a couple of paths we can take.

1. Tension of a standard bass 'E' string is about 40lbs, so we can calculate what gauge string would be required - this is a good option as it keeps the string tension balanced across the neck. This gives us a .225" string, which is about twice as thick as a standard 'E', which in turn makes complete sense.

2. We find the heaviest gauge string available and calculate the tension - this is probably the only viable option because you probably can't get such heavy gauge strings. It seems Conklin do a .194" (http://www.conklinguitars.com/bass_strings.html) which calculates out at about 31lbs. I have no real feel for that, but I'm guessing it's going to be pretty floppy.

Now it's up to you to go and try it...and maybe spend longer than 2 minutes looking for heavy gauge strings like I did.
Quote by von Layzonfon
So, if I'm reading that right you're actually tuning an octave below a normal bass?

With reference to http://www.seventhstring.com/resources/notefrequencies.html that would be E=20.6Hz, which is lower than the bottom note on a piano.

Lowest note on a piano is bottom A, same as on my bass. You will just have to go for that ridiculously thick string and hope it's enough tension. You might have to modify the bridge and/or tuners to get a mother****er like that to fit, anyway...
EH

"Show me war; show me pestilence; show me the blood-red hands of retribution..."
There's a major problem with this scheme. 20Hz is the bottom note people can hear and it really is right at the extreme, half the population can't hear it at all and for the rest of us it is at least 24dB down on what we hear of the vocal range of frequencies, this in turn means you would need 512x the power to reproduce the sound at the same level as midrange. You'd need 51,200W to match the 100W amp you have, you'd also have to find a speaker to handle this and which had a resonance below 20Hz. You are probably only going to hear the fundamental on headphones.

The truth is that much of what we hear is not the deep bass of the fundamental but the harmonics and what most people call deep bass is just a rich mix of the lower harmonics. Almost no bass speakers can reproduce the low E fundamental of a standard 4 string at any decent volume.

Here's the fun bit http://onlinetonegenerator.com/ play, then change the frequency to 41Hz (bottom E) it'll seem quieter but that's your ears not the machine, deep huh! Now try 20Hz, you might not hear anything but it is there.
Last edited by Phil Starr at Apr 19, 2013,
Quote by Phil Starr
There's a major problem with this scheme. 20Hz is the bottom note people can hear ...

I completely forgot about that side of things. It crossed my mind as I started my writing but never came back. Excellent point.
well, i guess a different course of action will have to be taken :-) thank you all very very much. maybe we will just drop the B to A Flat and call it good. :-)