CLX subwoofer intergration!!!!

awsmone said:

The bane of electrostatics is getting good bass

CLX go down to 50 hz little below

They have a lot of mid bass in 60-90 zone

With i think a resonate mode at 70

Getting deep bass to integrate is hard, as you fill in the bass with subwoofers the 70 hz peak seems to thicken the otherwise lithe bass/midbass

Thanks to this site, Nyal and Earl Geddes:-

I have experimented with four subwoofers

In my largish room 13 metres by 6.5 metres by 2.5 metres

I run a idescent with clx cross over at 30

This is run from an external digital crossover with super tweeter cutting at 16khz as an ambience driver

using peq i cut the 70 hx peak by 10 db 1/10 octave

i run delay of 12 msec which i tuned by ear

three other subwoofers slave off this

one centrally running back at the idescent which is in plane of clx speakers

and two others on rear walls running destructively one for each panel in stereo straight back at them(clx)

Measurements show bass between peaks from room modes filled in and peaks smoothed


The clarity and depth and speed of bass is wonderful and beautifully integrated

Very happy

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awsmone said:

Thanks to this site, Nyal and Earl Geddes:-

I have experimented with four subwoofers...

Measurements show bass between peaks from room modes filled in and peaks smoothed

The clarity and depth and speed of bass is wonderful and beautifully integrated

Very happy

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Duke LeJeune said:

Earl Geddes was my mentor when it comes to subwoofer systems.

I had spent years trying to come up with a subwoofer that could "keep up" with a good dipole and have good impact. Sealed, EBS vented, aperiodic, equalized dipole, isobaric, transmission line. None of them delivered the goods.

Then one day Earl described to me his asymmetrical multi-sub configuration. The lightbulb went off in my head. I asked him if I could license his idea. He said I was free to use it, and I have been doing so ever since.

It just so happens that, at the same time Earl was developing his asymmetrical multisub concept, Todd Welti of Harmon International was developing a symmetrical multisub concept. Neither was aware of the other's work until after they had both finished.

Smooth bass = fast bass, subjectively. The ear has poor time-domain resolution at low frequencies, but it can still hear a bass peak as "boom" or "mud". Once the in-room response has been smoothed by multiple subs intelligently distributed, it is much easier to get a good blend with a good pair of dipoles.

Earl once posted that, as a reasonable approximation, the in-room bass smoothness increases as the number of independent bass sources within the room increases. So two subs is "twice as smooth" as one sub, and four subs is "twice as smooth" as two subs. The subjective improvement is even better than a statistical analysis of the new smoother curve would predict: You see, a distributed multisub system not only has smaller peaks and dips, they are also more numerous and therefore bunched up closer together, and the ear/brain system tends to average out peaks and dips that occur within 1/3 octave of each other at bass frequencies.

According to research by James M. Kates, dipoles are smoother in-room than monopoles. Four distributed subs can approximate the in-room smoothness of a good pair of dipoles, but they can do so with the impact that eludes dipoles.

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FrantzM said:

(...) The audiophile world is not warm to the idea of multiple Low-bass source. We are still mired in the bass (towers) flanking the main speakers and still want tenaciously to believe in "stereo" bass under 50 Hz. There are some changes coming around , lately from Von Shcweikert using DSP and distributed subwoofers. Two of these in the back of the listener and using DSP... another concept many audiophiles find unpalatable... Anyway multi-subs is the way to go and work with most any speakers if care is taken.

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FrantzM said:

microstrip

You seem to have made it a mission in your life to take the counter-position of whatever I post. it is all good. it makes it a challenge. Your paper seems however to support my point that there is no stereo bass under 50 Hz or since you like to so much to split hair under 45 Hz ...

It is not a matter of value for the money but of excellence in reproduction. On that multiple subwoofers wouldn't be the first choice for lowest cost, especially with already expensive full range main speakers... Integration is not an "obscure affair". Multiple subwoofer integration has been thoroughly studied and advocated by the likes off Todd Welti, DeVantier, Floyd Toole and Earl Geddes . Do you have any study proving the contrary? Would like to see those?
As for your interesting claim , that of the High End Community being an "open mind" ... It could well be true ...when people are willing to acept that a few dots on a wall make a "huge" difference.

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microstrip said:

Well, some people could consider you suffer from the persecutory delusion. I post very often to WBF, my target is not your posts, but sometimes the posts from people who try to characterize audiophile behavior in general, admitting all of them suffer from the poster youth sins. Yes, I admit that the style of the repented sinner who suddenly saw the light is not my favorite and triggers my attention ... Let go to the welcome challenge.

First a question of vocabulary - in my post integration means blending the subs with the main system - something that was never debated by the people you refer, specially at 50 Hz. They all admit the 80 Hz crossover is good enough and do not debate the transition, except for frequency response. Secondly, the aim of the likes off Todd Welti, DeVantier and Floyd Toole (several authors but the same studies in general) is multichannel bass reproduction with adequate quality over an area that is significant versus total area of the room. F. Toole explicitly refers in his papers that for typical audiophile conditions (a small seat area) other methods are enough. Earl Geddes method is strongly dependent on a small area listening position and is nowhere related with the other authors - as far as I know it is really original work from another great researcher, scholar and designer. As people know I dislike when people who have not read the papers try to mix everything in a common bowl.

BTW, as Amir has posted sometime ago, the old multi-sub techniques of the Harman group have been overtaken by their modern self adjust systems using individual equalization of each sub. The current JBL Synthesis bass management system is really something fantastic, but unfortunately proprietary and not at the reach of amateurs.

For what is worth, I have been playing with two Descent I subs in my system. Still too early to post about it. Again, audiophiles opinion is created by their experiences and also detailed and believable reports, not sensationalist comments on dots.

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microstrip said:

Earl Geddes method is strongly dependent on a small area listening position and is nowhere related with the other authors...

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