bassguitar physics and cabinets

[Baltar]

hi folks,

im getting confused on planning the speakerscabs for
my bass amplification

on the one hand i just could go, buy a cab, play it and don't
worry, but i can't. i need to understand it ...

thinking of my first idea to get me a 210, which seems
to be a good first part i ran into an threoretical issue:
how can you play bass on a cab, which doesn't reproduce the
frequency of you lower strings?

perhaps it's just the selection of cabs i looked at, but
most of the 210ths do start playin at 50 or 55 Hz ...

ok, 55, that's an A string.
but what about the E, which should shake the small thing with
sth like 41Hz?
Did i mention, that i have an H-string :blackeye: , ... which i
sometimes use on the 2nd fret, which is short above 35Hz

how does that work?

by the way .. the gallien-krueger 115 cab is also labled with
50Hz-5kHz - so it's a general issue of efficiency and size ratio.
perhaps 4 112 cabs with 140litres each, will provide me the
sound i desire, but i got to go for a pickup-truck then
so what do i do if size matters? small speakers with high wattage
and equalizer torture? can't be - or what?

thanks in advance for you input :bowdown:

 

[Marcel]

Re: bassguitar physics and cabinets

50Hz doesn't mean that frequency below isn't reproduced...it's just less volume under this 50Hz... go to the celestion page (f/e) and you're gonne find some diagrams of the speakers ..

 

[Baltar]

Re: bassguitar physics and cabinets

a cab which does starts at 50 Hz, is already 3dB below it's
average at 50Hz. That's half the volume you sense.
And eg 9dB at 40Hz below average level is already a huge difference.

sure, you can hear it. but it doesn't sound good, or am i wrong?

 

[GuitarStv]

Re: bassguitar physics and cabinets

You're not wrong, it just depends on the specs that you're reading. Remember too that much below 50 Hz and barely hear any notes, just kind of feel them. The bass cab doesn't just produce the super low frequency, there are a lot of mid/highs that need to be reproduced to get a nice bass sound too, and they can fill up the sound when the lows are underperforming. . .

 

[Marcel]

Re: bassguitar physics and cabinets

I thought it's more 6db/octave which would mean
-9db @ 25 Hz or am I wrong.
I think most bass cabs are bassreflex... with the right volume or right bassreflex tube you can emphasize the frequence around 50Hz to get a deeper low end response ....

 

[Marcel]

Re: bassguitar physics and cabinets

or the low frequence is boosted on the amp... that's what AFAIK a resonant control on some amps do

 

[Baltar]

Re: bassguitar physics and cabinets

You're not wrong, it just depends on the specs that you're reading. Remember too that much below 50 Hz and barely hear any notes, just kind of feel them. The bass cab doesn't just produce the super low frequency, there are a lot of mid/highs that need to be reproduced to get a nice bass sound too, and they can fill up the sound when the lows are underperforming. . .

thanks for clarification. that helps

I thought it's more 6db/octave which would mean
-9db @ 25 Hz or am I wrong.
I think most bass cabs are bassreflex... with the right volume or right bassreflex tube you can emphasize the frequence around 50Hz to get a deeper low end response ....

i was just estimating the drop. since two days i'm playing around with
a cab simulation program and several eminence speakers.

right, bassreflex is more popular. because it defines a sharper low cut and
is therefore more efficient. the problem is in limited cabsize you need to
go closed to make the speaker sound good. i'm a fan of closed cabs,
which isn't senseful for pa. so i have to go for a big cab and bassreflex
what i tried to avoid :blackeye:

 

[Marcel]

Re: bassguitar physics and cabinets

I think deep bass response is simply not needed... I'm neither sure nor a bass player but I think it works for most people so there should be no problem...

It isn't just the base frequency of for example 55Hz for an A there are overtones... and the base frequence is still played ...it still exists

In this frequency range there isn't much about hearing it's more about feeling ...

So the question is better why should this not work???

 

[Lake Placid Blues]

Re: bassguitar physics and cabinets

Back in the distorted bass days they always had problems when trying to amplify the lower fundamentals. The old technology speakers would fart and they would have vibration problems on stage.

The ampeg system solved this by using 8x10" cabs. The harmonics of the fundamental could come through clear, and since the 5th harmonic is the main part of any given notes tone it still sounded deep and warm. The lowest fundamentals would not be causing problems

The use of 10" speakers was surprizingly found to be very benificial to bass. Compared to a 12", 15", or even 18" ; the 10" has less mass and can respond faster, giving a more articulate bass tone.

If I was building a modern bass rig, I would make a 4x10 (with high slew rate speakers, such as aluminum cone) the main cabinet.

You could always use a ported 1X15", also using as fast as possible 15", to fill out the lower end some. You could simply stack the 4x10 atop the 1x15, making a neat, effective and compact bass stack.

 

[Baltar]

Re: bassguitar physics and cabinets

as i see, taste is different here :laugh2:
but thats great and the way it should be

on saturday i gigged an borrowed 150W Keyboard combo, which worked
surprisingly good. perhaps it lacked a little repsonse, but it was close to good.
i think it was 15" vented + horn

idea: i thought of building a highend 112+horn cab, with real tough drivers
(thinking of an kappa 12, which has a great efficiency, low end and
power handling) and combine with other cabs as needed.
if it lacks response and clarity i could mix it with a 210 or 4x8 cab.
if it's still not enough low end for my taste, i could add a 118 woofer.

right way? wrong way?

cheers

 

[Lake Placid Blues]

Re: bassguitar physics and cabinets

Also consider the the Celestion range of neo magnet bass speakers. They have a 12" version for bass if I recall correctly. I know that the Celestion neo magnet guitar speakers are not very popular, but these may be just what a bass cab needs. Compared to regular bass speakers they are significantly more efficient and lower mass. This would effectively increase the head room of the amp, and probably the articulation.

 

[Baltar]

Re: bassguitar physics and cabinets

thanks, i take a closer look at it

 

[The Golden Boy]

Re: bassguitar physics and cabinets

Low E is around 42hz. Low B is around 30.

I prefer the sound of 15s to tens or 8s, and I haven't played a newer 18, nor have I used 12s. Speakers have come a long, long way- even in the last 10 years or so. Where I used to use GK cabs loaded with 400w EV 15s and I thought those cabs smoked. When I tried an SWR Triad with the PAS 15 in it, it was a whole new world of "richness" in the tone.

You could always use a ported 1X15", also using as fast as possible 15", to fill out the lower end some. You could simply stack the 4x10 atop the 1x15, making a neat, effective and compact bass stack.

I always used to do it like that, stack the 4x10 on the Triad, until I played a show where someone else had stacked my cabs and put the Triad on top- that's when I really heard that 15 and truly realized I like the sound of the 15 much more than 10s.

Check out the "Amps" forum at TalkBass-
http://www.talkbass.com/forum/forumdisplay.php?f=15