ATC/Volt midrange drivers and 118 dB SPL, continuous?

[soundbloke]

note that it has a small waveguide which gives the sensitivity somewhat of a boost

Hardly any difference in reality.

Please note also that the business of this thread was in the process of being answered in another thread - namely "ATC SCM200 ASL Pro". I would suggest merging these threads and I wonder why another has been started?

 

[soundbloke]

Of course the power rating of loudspeaker drive units has been rather meaningless for years anyway

Indeed they have!

As to the effects of heating please see my previous answers to questions posed in the original "ATC SCM200 ASL Pro" thread: Thermal compression effects and transient clipping aside, the main thrust for wanting high power handling capacity is the requirement for reliability.

 

[phase_accurate]

Just for fun:
x-max @ 450hz @ 240w @ 112 dB
=> x-max @ 900hz @ 960w @ 124 dB
=> x-max @ 1800hz @ 3840watts @ 136 dB
=> x-max @ 3600hz @ 15k watts @ 148 dB

While the excursion related ratios are correct - the power ratios definitely aren't.
The correct table should be:

x-max @ 450hz @ 240 W @ 112 dB
=> x-max @ 900hz @ 3840 W @ 124 dB
=> x-max @ 1800hz @ 61.44 kW @ 136 dB
=> x-max @ 3600hz @ 0.983 MW @ 148 dB
😉

Regards

Charles

 

[KSTR]

I know Weltersys did some destructive testing of a TC9FD full range driver in a FLH to see how much power it takes to let the magic smoke out. These drivers are rated by Vifa as 30w rms and 60w max. IIRC it was able to handle some insane number like 400w. Also, with a steep high pass filter, dynamic bursts of perhaps 1 second at ~kW was applied and the driver survived - I think that work was done by Barleywater.

Just to add another data point, I've tested small AMT tweeters with ~10W continuous sine power handling for transient withstanding capability and they survived 500Watts (amp hard-clipping to square wave) for several hundred ms before the limiter had to kick in. I usually go for 10x sine power handling of the driver when I spec amps but I actually was surprised that 50x still was OK for that fragile tweeter once the limiter was set up correctly.