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PostPosted: Thu Feb 26, 2009 12:27 pm
by Ted
Ha. I'm guessing your man at Bose is not a listener to heavy, heavy dub.

An Ampeg SVT may very well be specified down to to 55Hz. I presume he's referring to an SVT with something like the matching Ampeg 8 x 10 cabinet. Below that the response "rolls off" so it doesn't just cut off anything below 55Hz - its still producing sound at 30Hz.

Its a very common and recognisable rock bass sound. But thats a late 60s amp and cabinet design. Bass amplification has come on a long way since then. You wouldn't really associate the SVT's fearsome snarl with dance music bass sounds.

Modern bass amp/speaker combinations are typically specified to 40 or 45 Hz.

PostPosted: Thu Feb 26, 2009 12:36 pm
by Neil Foxlee
I said
Though I stand to be corrected, I've never come across loudspeakers that go below 40 Hz.


Ted said:
Modern bass amp/speaker combinations are typically specified to 40 or 45 Hz.


So where do we disagree?

PostPosted: Fri Feb 27, 2009 10:20 am
by Ted
Neil Foxlee wrote:Though I stand to be corrected, I've never come across loudspeakers that go below 40 Hz.


When a speaker is specified down to a frequency its response is nominally flat down to that frequency, and below it the reponse gradually reduces - which is the point that the Bose man was making - that it still reproduces sound at 30Hz just at reduced intesnity
Ted said:
Modern bass amp/speaker combinations are typically specified to 40 or 45 Hz.

So where do we disagree?


Sorry - I was talking about bass guitar amplifiers - lost sight of the general nature of the discussion. The bass and sub bass speakers of PAs go well below 40Hz.

An interesting thing to play with (if you're concerned about this kind of thing and have half an hour to mess about) is WinISD Pro.
http://www.linearteam.dk/default.aspx?pageid=winisdpro

PostPosted: Fri Feb 27, 2009 11:05 am
by Neil Foxlee
Ted, I should probably have said that I've never seen speaker specifications that go below 40k. You don't build speakers in your spare time, do you (I myself built some Lowther folded-horn ones once)?

PostPosted: Fri Mar 20, 2009 7:40 am
by joel
Neil Foxlee wrote:According to the diagram given by Ehrlich (1983), for example, reggae bass covers a spectrum of c.150 to 250 Hz. Though I stand to be corrected, I've never come across loudspeakers that go below 40 Hz.


Here are some quick & dirty measurements I took this morning using a software package that's being evaluated at the moment.

Do not try to make direct comparisons between songs, as I have not calibrated the input levels for each piece and 1/3 octave band measurement is not a precision tool at the best of times...

Still, these charts give an approximate indication of the energy to be found at a single point in a variety of music tracks (the data are read directly from file; no loudspeakers were involved in the making of this post).

Very large JPEGS, but they need to be to read off the charts:

1/ Meshell Ndegeocello: Love Song #1
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A bass heavy mix which augments Meshell's electric bass with synthesized bass way down into the 20s.

2/ Culture: Natty Dread Taking Over
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Not an especially bass-heavy track by Reggae standards


3/ Lunar Dunes: Herzegovina
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Say hello to Adam's bass (or not: Adam's on guitar...)

4/ Marcel Peres - Graduel: Tecum Principium
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Male voices recorded live in a medieval church. Lots of energy across the spectrum.

Garifuna Collective: Sun has set
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Silvana Deluigi - Mariana
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Powerful double bass doesn't come through too clearly in this slice.


Neil Foxlee wrote:Ted, I should probably have said that I've never seen speaker specifications that go below 40k.

As Ted says bass response rolls off more-or-less gradually in speakers. Many speakers have audible response at 40Hz, but it's usually down a few db vs 100Hz.
In a typical UK domestic situation, this is not a bad thing, as the room itself reinforces LF, although further interactions between reflex port tuning and the room's resonant frequencies can make things quite complicated.

PostPosted: Tue Oct 06, 2009 3:55 pm
by Charlie
Listening to the Francophonic compilations just released on Sterns, I'm struck again by how important and distinctive the bass-playing is. Not just in Franco's music, but in all African music - I think you can recognise the nationality of most African records from the bass lines, a better guide than any other element of the music. A curiosity of the otherwise excellent album by The Very Best is the virtual absence of any significant bass lines, giving the album a strangely rootless feel in every sense. Can we have some wise words on the role of bass, from the man who plays it?

By the way, Joel, all the pix in your flckr message have disappeared.