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Intermediate Member
Username: mpisanek

Post Number: 168
Registered: 1-2005
Posted on Friday, August 18, 2006 - 3:06 am:   Edit Post

I'm sure this has been discussed earlier somewhere on this forum, but I can't find it using the search.

I was wondering if anyone could tell me exactly what frequencies are produced by a bass with a low B string and having a 34 inch scale length. I would also be interested in the frequencies that are produced by a 42" scale electric upright with a low B string as well.

The reason I'm asking is that even bass gear seems to be varied in the low frequencies it will handle. For example, the Boss GEB7 bass EQ pedal will handle down to only 70 hz while the Aphex Bass Exciter will handle down to as low as 30 Hz.

I don't know what the frequency range of the F1-X that I use is, but my power amp, and my speaker cabinet will produce down to as low as 27 hz.

I've been looking on the net and can't locate the frequency responses of things like the Line6 Pod stuff, or the Boss ME-6B. My concern with equipment like this is that the input frequenies will be cut somewhere and the output frequencies of such devices will be something like 20-20,000 hz.

I was also wondering about the high end as well. Many bass cabinets (even with horns) will cut off at 14Khz or so, and some will cut off at slightly higher frequencies.

Are the frequencies I am talking about outside the realm of the average bass pickup anyway?

Am I being silly by even worrying about such things?
Senior Member
Username: dadabass2001

Post Number: 656
Registered: 6-2002
Posted on Friday, August 18, 2006 - 5:51 am:   Edit Post

According to this chart the low B frequency is 30.87 Hz, low E on a standard 4 string is 41.2 Hz, open A is 55 Hz, and the 24th fret on the G string is 392 Hz.
That Boss GEB7 is apparently only working on harmonics until you get up to the open D. The upper harmonics add alot of qualities but only to a certain range, e.g. the top end of Alembic's filter circuit in Series instruments is listed here somewhere. I remember two numbers running around 3,500 Hz or 6,000 Hz

Hope this helps..
Senior Member
Username: kmh364

Post Number: 1989
Registered: 9-2003
Posted on Friday, August 18, 2006 - 6:34 am:   Edit Post

As an aside, frequency response specs. are meaningless without limits. For example, a frequency response spec must have the response level in decibels (dB), i.e., 20-20kHz +/- 3dB. While it is impossible to tell which response level relative to zero corresponds to which frequency (without a graphic representation of the frequency response curve), at least you know that the particular device's output cannot be lower than 3dB @ 20hz relative to 0dBm using the above as an example.

The point of all this is to remember that while a particular device may be purported to have response down to 27Hz, the relative level of that response could be 10-20db (or more) lower than the reference(remember, the decibel is a logarithmic measurement...a appreciable change in level only 3dB down from reference already represents a signal at half-power output).

My word to the wise: don't get caught up in specs! Use your ears and gray matter.
Username: paulman

Post Number: 74
Registered: 2-2005
Posted on Friday, August 18, 2006 - 9:45 am:   Edit Post

Heh Wall of Sound...Phil's Stacks were 32 feet high so he could generate an entire E note wave form. At least, that's what I read from Bear's interviews etc. Apparently it was at a nice, pleasent DB level too.

My Bass player finally got his 4th B-52 sub for the rig so he can get a lot of the B freq out at a really decent DB level woo hoo. After a certain point you have to move the right amount of air to get the proper freq clean at a good DB.

We'll be trying it finally tommorrow at a party :D. His goal is to get flat response from his B string to his C string (6 string tuned BEADGC) but lemme tell ya, I'd hate to see him in a g string. Guffaw!
Advanced Member
Username: byoung

Post Number: 352
Registered: 12-2004
Posted on Friday, August 18, 2006 - 6:14 pm:   Edit Post


That whole "reproducing the B-string" is leading me towards Bag End and one of their INFRA (formerly ELF) systems. The technology was designed by The Ron himself.

Most speakers/gear that say they have a response curve 20Hz-20KHz simply don't. Almost no speakers out there are really flat below, say, 50Hz. Yes, including subs.

Senior Member
Username: bigredbass

Post Number: 974
Registered: 9-2002
Posted on Friday, August 18, 2006 - 6:51 pm:   Edit Post

The only practical way to approach sub-100hz notes in a bass rig of a reasonably manageable size is ELF (or INFRA). Without it, you can have your own WallofSound, several big amps, a van, and a couple of stout brother-in-laws to help.

I went through this and came out the other end feeling this way: Most of the bass we hear well is around 80 or 100 hz, which most cabinets can do pretty well. Remember, the low B fundamental is TWO octaves below this, and they happen to be the two hardest octaves to do right. Ever see the massive 4-18 subs that Touring Sound companies use? They ain't just for looks, you're moving BIG air in the 20-40hz range.

Out past 4 or 5k, there's nothing going on for a bass guitar in a practical sense for my ears.

Try this: Next time you're around a electronic repair shop, most scopes have tone generators in them that will make pure tones (no harmonics), and listen to Low B. Hear these tones, and a lot of this becomes academic real fast. It dawned on me I DON'T need a PA or Studio Monitor response for bass.

There's a big difference between pure laboratory specs/response and something that sounds musical.

I'll take musical every time.

J o e y
Username: davehouck

Post Number: 4286
Registered: 5-2002
Posted on Friday, August 18, 2006 - 7:04 pm:   Edit Post

Hi Mike; here is a great thread related to your question.
Senior Member
Username: dnburgess

Post Number: 484
Registered: 1-2003
Posted on Friday, August 18, 2006 - 11:38 pm:   Edit Post

Acme cab.s have the best low B response that I have heard for boxes anywhere near that size. They are -6dB @ 30.87Hz which is excellent.

To get equivalent or better performance in, say, Accugroove, you are looking at an El Whappo or above.
Advanced Member
Username: byoung

Post Number: 356
Registered: 12-2004
Posted on Friday, August 18, 2006 - 11:51 pm:   Edit Post


I haven't heard anyone suggest (even faintly) that the Bag End gear is un-musical. I don't think that's what you were trying to say, but just checking.

I agree, musical is most important.

Senior Member
Username: bigredbass

Post Number: 975
Registered: 9-2002
Posted on Saturday, August 19, 2006 - 6:45 pm:   Edit Post

No, I just think faster than I type! ELF is certainly musical. I was trying to say I've heard bi- and tri-amped rigs that were PAs for bass that just weren't as satisfying for me as a good amp. And much larger than an ELF rig.

J o e y

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