advertisement


speakers that go below 20hz

Hi Tony

Not in my experience.. the light paper cone used by Tannoy (and indeed most sensitive speakers) allows a very high crossover point for such a large woofer. It is basicaly a mid and bass driver.

This produces a great sound, but to get flat to 20hz you would need ... normally a driver with huge xmax dedicated to low bass, or with your drive units, more than a back loaded horn - perhaps a 20 foot horn might do it!

None of this detracts from the wonderful sound you get from large Tannoy drive units or in fact of course the point that there is little 'music' below about 40hz - having a loudspeaker capably of producing 40hz comfortably (such as a 15" tannoy dual concentric) makes for great sounding bass in my opinion.. for music, perhaps you would want more for movies..

... and this is surely where '20hz' and dedicated subwoofers come into play.

In my own system my 15" tad bass units (which are paper cones in many ways not dissimilar to units by altec, vitavox, tannoy.. ) are flat in their cabinets to 40hz in room, and drop from there.

Its my opinion and perception that audiophiles and indeed the general public associate deep, rumbling bass with low frequencies. However, having ample and generous bass in a higher frequency range - generally speaking Id say around 60-80hz is going to give you that thick, generous bass people want.

Disbelievers should listen to a few test tones -

50hz - http://www.youtube.com/watch?v=RBd8v-M-TV8&feature=related
80hz - http://www.youtube.com/watch?v=ZnCSTNATFqw&feature=related

... the question for music lovers seeking to fill a large room with deep bass - would better be posed as ...

how much air can my bass drivers move in the 60-80hz region? (clean, flat response, low distortion)
 
When looking at in-room response, obviously high notes and low notes (ignoring room influenced peaks) suffer.

The extremely substantial Tannoy Westminsters begin to drop from 40hz when measured in room

http://murphyblaster.com/content.php?f=various.html


This is a far more substantial speaker (in size and ability to move air) than others I have seen in this thread, but makes no attempt to perform subwoofer level theatrics.

Unless you're listening to depth charges going off in a movie about submarines, I really dont see the point of 20hz for a 'music' pair of speakers.. even the oft-quoted 'organ music' sounds better (in my subjective opinion) with a speaker capable of fully providing generous bass in the 60-100hz range (as a priority over very low bass notes).
 
Celestion Ditton 66s' go down to 16, will shake the house to pieces but not in a slow flaby way; very good indeed.

I have Kef 104.2s at the mo, very good low down too.
 
This 'goes down to' is pretty meaningless as the drivers involved cannot produce any meaningful output at those frequencies(see IMF response plot) and even if they tried they would distort horribly as they bottom and burn out.
 
cooky1257 said:
This 'goes down to' is pretty meaningless as the drivers involved cannot produce any meaningful output at those frequencies(see IMF response plot) and even if they tried they would distort horribly as they bottom and burn out.
Click to expand...

Dynaudio claims ±3dB @ 17Hz for the Consequence Ultimate Edition. I guess that's possible if you have a quasi-isobaric chamber, driven by two 12in bass drivers.
 
bottleneck said:
Not in my experience.. the light paper cone used by Tannoy (and indeed most sensitive speakers) allows a very high crossover point for such a large woofer. It is basicaly a mid and bass driver.
Click to expand...

I agree to a large degree, this is certainly true of own implementation - they get down to about 35Hz.. just:

3945256119_347e1ee8a4_o.jpg


The graph is both sides driven measured from my listening seat. From a subjective perspective they can do a bottom E fairly convincingly but drop very rapidly indeed below there. I've tried running sine waves from 20Hz in 1Hz increments and I can only start to hear some fundamental above 35Hz.

The speakers are in a rigid sealed (to a degree at least) box of about 75L. I understand that say Autographs can get the same driver down a lot further, but obviously we are talking something absolutely huge and remarkably expensive here.

bottleneck said:
... the question for music lovers seeking to fill a large room with deep bass - would better be posed as ...

how much air can my bass drivers move in the 60-80hz region? (clean, flat response, low distortion)
Click to expand...

I agree completely. It's all about shifting air without any strain or effort, and IMO that takes a big driver. The only thing I'd argue is I'd like some real energy down to 35-40Hz or so, a bass / bass guitar guitar bottom E is 41.5Hz, and to my mind the music suffers if a speaker is only capable of delivering harmonics there (e.g. my Klipsch Heresys which are out of the game at about 50-55Hz). It's easy to argue there is a lot below 40Hz too, a kick drum effectively rises rapidly from a 0Hz thwack, as indeed does a nice big bass amp etc, i.e. you pluck / hit the string and there is a hefty subsonic thud as the speaker reacts that constitutes much of the leading edge of the note, the sound of the string and speaker rapidly accelerating to pitch, think big Ampeg horn cab. I'd file that as nice to have out of a home stereo rather than essential, but the bottom E is part of the music, we needs that!

Tony.
 
I used to own the Revel B15 sub, which is a $3000 subwoofer - details here

http://www.soundstage.com/revequip/revel_b15.htm

At the time I was running a 3 way horn system with Altec drive units/ JBL drive units.

The Altec went down to 40hz, much as most efficient 15" paper cones do. I thought I needed more below that, and in came the revel (and out went my cheque book).

I was amazed by how little difference it actually made, and the bass I was lacking, more an issue of having a poor room acoustic.

This of course is another point entirely and room acoustics are capable of sucking out more bass than the biggest bad-arse system is capable of adding (within some limits :)
 
I Know my activ Briks go down way past that level, when tested with the HiFi News analogue test record, using vertical and lateral resonance test tracks.
Certainly does make you feel queasy as others have said!
Rich
 
ProAc Response 4 goes down like this according to the spec.

But if you want something which really can generate 100+ dB around 20 Hz consider Danley subs. In room measurement of the double TH SPUD coach sub.

post-50-1281724075.jpg
 
What are them twin tower "things" behind the sofa?
Also i think you should put some mesh over the mouths of the subs in case a pet/child/raccoon climbs inside (and is wobbled to pieces).
 
muz640 said:
What are them twin tower "things" behind the sofa?
Also i think you should put some mesh over the mouths of the subs in case a pet/child/raccoon climbs inside (and is wobbled to pieces).
Click to expand...

Mesh is not a problem it is part of the package. Those towers can be two other subs, so called DTS20s probably?
 
You must log in or register to reply here.


advertisement


Back
Top