• The move to the new server is done. There are some software and database maintenance updates in process. This has us passing the hat around to help out. We appreciate any donations. Seriously, even a dollar helps. The payment page may be found here - https://www.audiokarma.org/support.html

Do two 6" woofers = one 12" woofer ?

I think the reason tower speakers with multiple drivers are so popular is mostly astetics. People want them. Or more specifically the narrow cabinets.

As far as sound goes. IMO a well designed tower can perform as well as a well designed larger box. Energy's RC 50 Towers with 2 x 6.5" woofers easily outperforms the Realistic Mack Ones I had with its 15" woofer, Including deep puchy bass. No amount of modifications would bring them close.

On the other hand, I'll bet the New KLH Five with its 12" woofer sounds really good. I love that it's acoustic suspension. No more bass thump from the port, just a nice smooth roll off at a respectable 42 hz @ -3 db's.
 
Sitka said:
if you have small speakers ( anything under 12" IMO ) most likely you need a sub. My speakers are large, 15" - haven't used my sub for a long time. Everyone is different, and of course the room will dictate what works best.
Click to expand...
My AR 93s don't need a sub for my big stereo but I have a sub in my living room system for my AR 18b 6.5 woofer not the 8in as in the 18s
 
karik57 said:
This is correct. In real life the effective diameter of a 12" or 6" (or any other size) driver is not 12" or 6" because cone surround decreases that and every surround has not the same width, but if the effective diameters really are 12" and 6", then a 12" driver has exactly 4 times the effective area than a 6" driver or 2 times the effective area of a 8,5" driver (if there is such a size).

If the linear excursion is the same in all those drivers, then the maximum displacement volume of one 12" driver will be the same as four 6" drivers or two 8,5" drivers and thus the maximum sound pressure level will be the same. This is independent of the room size. Bass tuning is disregarded here.

The inner half of the surround belongs to the effective area and the outer half of the surround does not. If we assume that the outer half reduces the effective diameter in both cases by one inch (half an inch on both sides) then the true effective diameters would be 11" and 5". Then one 12" driver would correspond five 6" drivers (4,84 to be exact).

In loudspeakers size matters.
Click to expand...

Agreed.

As this is theoretical, I just simply took the ratio of 6" and 12" drivers as flat planes for simplicity to make a point.

I am fully aware of the true radiating area calculations for specific loudspeaker drivers and that the low frequency response behaviour of loudspeakers have a multitude of variables. I just wanted to give a simple answer to a simple question.
 
Mr Boochie said:
But, if you turn the subs off, with the rest of the speakers playing --- big difference. Especially, at mid to lower volumes.
Click to expand...
I claim no expertise but I think the lower volumes are when the subs benefit most in a music only environment.
I'm certain the room & other equipment factor in to a large degree also.
There are a lot of variables here.
 
Bob in WI said:
I claim no expertise but I think the lower volumes are when the subs benefit most in a music only environment.
I'm certain the room & other equipment factor in to a large degree also.
There are a lot of variables here.
Click to expand...
Definitely, a big plus at lower to moderate volumes. It seems that the imaging of the music is better with subs, at these volumes.
 
I recall Martin Colloms commenting in his review of the Magico S5 Mk2's for TAS, that a pair of the new 10" woofers was equivalent to a 14" woofer
 
toddalin said:
No, not necessarily. While two 8.5" may have the same cone area and even displacement, there will be points where the two sound waves come together and reinforce each other adding an additional 3 dB. There will also be areas where they cancel each other. The idea is to select the arrangement that lets these happen at the desired frequency.
Click to expand...

You are obviously talking about mutual coupling. Mutual coupling occurs when two woofers are in phase, reproduce the same signal and are separated less than a quarter wavelength from each other. It is a result of an increase in radiation impedance. As the name indicates, the woofers are coupled together to work as one individual woofer having twice the effective area and also produce the same SPL as one bigger woofer having twice the effective area and the same excursion.

When we go up in frequency, mutual coupling starts to diminish between separation distances of a quarter wavelength and a half wavelength and finally when the separation distance is more than a half wavelength, the frequencies sum up partly in phase and partly out of phase.

Reading your post gives me a feeling that you are suggesting that two mutually coupled woofers may deliver more SPL than one woofer with twice the area and with the same excursion. That is not the case. If it were true then we could replace those two woofers with four smaller woofers or with eight even smaller woofers and so on. Loudspeaker manufacturers would make speakers where the front baffle would be full of extremely small woofers. No, no and no.

There is no substitute for a big woofer ...............except an even bigger woofer.
 
If you cross over at 250 Hz, a 1/4 wavelength is ~1 foot and a 1/2 wavelength is ~2 feet. It's easy enough to fit a couple small speakers within those distances.

And there certainly are speakers that use a few smaller woofers that are coupled.
 
toddalin said:
If you cross over at 250 Hz, a 1/4 wavelength is ~1 foot and a 1/2 wavelength is ~2 feet. It's easy enough to fit a couple small speakers within those distances.

And there certainly are speakers that use a few smaller woofers that are coupled.
Click to expand...
Similar to phase-coupled active and passive in the same cabinet. I still remember the first time I heard the SR8 setup in an Olympus. Quite impressive.
 
JazzVinyl said:
I completely agree about the Infinity RS-325.
Ported, but not boomy or flabby bass. I provided a stereo to my baby sister with a pair of these. They fill her large living room with great sound. I also maintain a pair for myself...freshly re-foamed.

I also employ a 12" inch sub...but very happy with the 6.5" implementation in the 325's.

View attachment 3016566
.
Click to expand...
You guys should find the larger ones, 425, 525, and 625. they use passive radiators, two of them matter of fact, and are simply fantastic. I will always wonder why oh why they didn't pair the EMIT with this speaker, it was designed so very well! internally, it's about the best bracing wise I've ever seen.

IMG_20231027_143957642.jpg
 
You must log in or register to reply here.
Back
Top Bottom