Technically speaking, is it possible yet to make a stereo system with the following criteria:
Harmonic distortion 80db below signal at say 100db output. (not quite 16bit but 0.001% from 20hz-20khz.)
-Flat on axis and even horizontal off axis response within 0.5db
-110db output.
Harmonic distortion 80db below signal at say 100db output. (not quite 16bit but 0.001% from 20hz-20khz.)
-Flat on axis and even horizontal off axis response within 0.5db
-110db output.
It's doubtful that speakers could ever have such low distortion or even response.
The 110dB output, ok.
The 110dB output, ok.
In most speakers distortion skyrockets at very low frequencies, due to the required cone displacement.
>20% THD figures are typical at 20Hz.
To keep distortion below 0.1% at 20Hz would require something like 8, maybe even 16, 15"-woofers per side.
But, luckily, THD at such low frequencies is rarely an issue, and a single 15" does the job more than adequately in real life, and for most types of music ;-)
Marco
>20% THD figures are typical at 20Hz.
To keep distortion below 0.1% at 20Hz would require something like 8, maybe even 16, 15"-woofers per side.
But, luckily, THD at such low frequencies is rarely an issue, and a single 15" does the job more than adequately in real life, and for most types of music ;-)
Marco
Is just a thought experiment. Thanks guys.
So I have a JBL 2452h 1.5 inch exit compression driver, which gives about -65db distortion from 1.2khz-14khz.
For bass, the best I'm aware of is the AE TD15m.
Is this about the best or is there anything significantly lower distortion than these drivers?
Thanks!
So I have a JBL 2452h 1.5 inch exit compression driver, which gives about -65db distortion from 1.2khz-14khz.
For bass, the best I'm aware of is the AE TD15m.
Is this about the best or is there anything significantly lower distortion than these drivers?
Thanks!
I don't think you're going to get significantly lower distortion by using alternative drivers in such a configuration, no. What you've got is already very good.
Using a Tuextent Be diaphragm in the compression driver would improve the figures further, but not dramatically.
Also keep in mind, though, that for the mid-high frequencies, distortion levels are going to be influenced by the waveguide/horn used, too.
assuming you could, would it be worth it?
Is there really going to be a worthwhile improvement in sound quality
Is there really going to be a worthwhile improvement in sound quality
So interestingly, if I'm reading it right, the Beym TPL 150H has significantly higher distortion than a JBL D2430K compression driver, but a much MUCH better impulse response? Poor impulse response would be a form of distortion though right? Is it not catered for within THD figures?
Impulse response is a time behavior. Ideally, the impulse response would only have linear distortion,
(due to frequency response and phase errors), and would not be included in measurements such as THD,
which is from nonlinear behavior.
(due to frequency response and phase errors), and would not be included in measurements such as THD,
which is from nonlinear behavior.
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1) Hard to say what you are reading, but possible, given the pleated diaphragm may be lighter, and the horns used are different.
2)Different metrics- speed of attack and decay, the impulse response describes the reaction of the system as a function of time. Harmonic distortion is additional frequencies not present in the original signal.
3) Quite a few studies on integration time vs frequency, and reverberation Like distortion, sensitivity to "time" varies quite a bit.
From the TPL150H spec sheet, THD at 100dB one meter appears to be around -50dB at 1kHz, rising to -40dB at 10kHz.
From
JBL 4367 Studio Monitor Loudspeaker Review - HomeTheaterHifi.com
the JBL D2430K (dual annular diaphragm) in the 4367 at 100dB one meter appears to be around -60dB at 1kHz, rising to -50dB at 5kHz. The D2430 woofer at that level has a bit less distortion.
The 4" diaphragm 2445/2360 combo at 1.5 meters and 100+ dB comes in at around -40 at 1kHz, rising to -20dB at 10kHz.
At typical home listening levels for most of us, the distortion components for speakers like the above will be below ambient noise levels. When listening at 100dB plus, you may find, like me, your hearing, rather than the speaker distortion is more of a problem.
So yes, academic pursuits. But take a listen, compare your distortion sensitivity to others:
Listening Test - How it works
Art
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