Hifi sound quality with PA SPL

70,s hero wrote: The subject is an endless discussion but for a start using very linear speakers along with thier accompanying amplifiers will outperform others that are designed for sound reinforcement due to the engineering differences.

I have measured amplifiers in addition to loudspeakers and what you are saying I have not encountered. I have measured home audio amplifiers in addition to pro audio amplifiers above 100 kHz and both will faithfully deliver the exact waveform providing neither is driven beyond their limits.

Once a loudspeaker begins to vibrate anything pertaining to linear will be subjected to TS Parameters calculated results, how the loudspeaker is reacting in the enclosure at the given SPL in addition to, its surroundings. Xmax does not play a factor on the calculated TS Parameters of a loudspeaker.

Home Audio speakers are not designed for high SPL use and are subjected to greater non-linear characteristics if driven under high SPL conditions than Sound Reinforcement Speakers.

Best Regards,  

70,s hero wrote:   The importance of all that you say is correct however, sound reinforcement and Hi Fi  (of a higher order) are slightly differing applications. I do think that the xmax is a very important engineering measurement with regards to non linearity, when we deal with high end Hi Fi, there are various factors that are known to contribute to distortion and the same can be said for sound reinforcement. as I said in my earlier post, the high currents and mechanical forces at play at high SPL contribute to a high order of distortion. The idea of high SPL in sound reinforcement and its engineering principles and how that relates to output is that given a sub driver for example, the  claim of its output and efficiency is directly related to  its cone travel and at a given force dependable upon many factors. the engineering principles to manufacturer say an 18 inch driver that has the preferred parameters of high end Hi Fi drivers simply do not exist. As you are aware, it is far better to employ multiple drivers using 300 watts each than one at 1200 watts. The application of Hi Fi quality sound reinforcement is a very expensive and exacting engineering challenge. Even then, we can safely say that the SPL will be limited in relation to distortion, the OP is quite open to interpretation but to my mind, I base it upon my own HiFi from a world leading manufacturer of such systems. That said there are many who can argue that the sound is not to thier taste and will dismiss what I say which is fair based upon thier experiences.

I've read so many Hi Fidelity fanatics focus on every formality and, cannot answer one simple question... "What is the measured frequency response of your loudspeaker?"

Assuming excursion can rectify a speaker that is -3 dB, -6 dB and/or, greater at the given frequency/frequencies while remaining linear is a marketing ploy that many are brainwashed into.

If a loudspeaker's frequency response in free air offers a consistent dB level (No deviation greater than +/- 1 dB) from 100 Hz - 30 Hz, comparing a driver with a high excursion figure versus a low excursion figure will hold no relevance. Only when the frequency response of the loudspeaker declines to the point there is an imbalance (Deviation ranging from +/- 10 dB from 100 Hz - 30 Hz), having a driver with a high xmax is relevant. 

The problem that many seem to overlook is there are lots of loudspeakers that offer a high degree of dips within the midrange to high frequency range in which, a driver that offers a high degree of xmax, will have no impact on the loudspeaker's performance at the given frequencies.

Equalising the problem areas may rectify the issue. However, boosting such frequencies will bring forth non-linear behaviour patterns due to forcing the loudspeaker to amplify frequencies the loudspeaker has difficulty producing. 

Best Regards,