UK IB Sub Suppliers Jul 19, 2009 2:39:12 GMT -7
Post by chrisbee on Jul 19, 2009 2:39:12 GMT -7
Impossible to say with any degree of certainty. There are so many variables. Though I would guess not on LFE programme material. Which is not the same as sinewave testing which is easily possible at much higher levels.
I managed to find the audible limits of four AEIB15s on some action films sitting at only 3 metres from the manifold. The AE's have similar displacement to the JBLs but may not have hard physical end stops. (Relying on the suspension to limit extreme cone excursions) Where Xmech relies on hard stops the drivers may have a short life if you intend to push the SPL limits so high on films. The more long throw cone area you can afford the higher the safe headroom.
I spent more than a year working slowly up to the listening levels I enjoy now. I could never put on a new film with complete confidence that I could listen at any level I chose. I would watch the drivers on every unexpected peak with trepidation. The problem was that I often hired up to six new films every weekend. Nobody wants to listen once at a safe level and then immediately watch the same film again at "normal" SPL levels having checked out the worst signal peaks on the film. Then there was the problem of LFE getting more extreme as new films seemed to be competing with each other. Directors don't flag that a sudden violent explosion is about to change our lives and that of the characters on the screen! There'd be no shock value!
Eventually I learned to relax and stopped worrying about driver excursion. I had discovered the performance envelope of my drivers by extensive experience watching literally hundreds of films. My hybrid analogue stereo/surround system does not have the usual AVR reference level +/- graduations. So I never really knew how loud I was listening without using an SPL meter.
Some CD players will quickly scan a whole CD for peak sound levels. I really think this ought to be a standard facility on DVD and Blu-Ray. Particularly as LFE keeps pushing the boundaries of what is possible to reproduce safely at reference level. Nobody would put up with cars which could not manage motorway speeds without blowing up! Why should we have subwoofers which cannot manage reference level on standardised LFE "fuel"?