Thought I'd start a new thread on distortion.
what is acceptable, what is audible, the different types etc.

For years amp makers have fought to display their distortion levels in 10ths and hundredths of a percent, however almost no speakers come with listed specs for distortion.

In the latest MTX ad in PAS, they claim a very low distortion on their sub as compared to the Kicker.
Maybe the times they are are a'changing!

what kind of distortion are they reffering to when talking about their subs?
Cone distortion? Voice-coil distortion?
Distortion IMO is quite mis-understood, over-rated, and by today's standards almost a moot point. Considering that my Juliette alarm clock radio has quite respectable specs(published) for today's standards.

They're comparing an L-7 to a Thunder8500.
THD + Noise at 40Hz, with 500 Watts input.

They claim to have measured 22.5% on the L-7, and 4.5% on the 8500.

No mention of the type of enclosures used, or what the specs are at slightly lower input levels....perhaps the Kicker is at it's limit at 500 watts.

Does distortion happen due to a dirty amp signal or too much gain or does it happen because the speaker just can't handle going that loud

Distortion happens because a speaker does a fairly lousy job of turning an electrical waveform into an audible one. Some designs do a better job than others but overall I'm surprised actually that the 8500 (or any woofer)tested that 'low'.

Unfortunately, it's all we got..

anyone know the FS on both drivers? could be a big factor.

Yo, most distortion caused soley by your driver is either because of non linear BL, cone breakup, or a result of coil inductance...

This particular example shows exactly how average an L7 is... although MTX probably cheated... [img]graemlins/jack.gif[/img]

Most people can't hear 10% distortion with music anyways. Most 'serious' audiophiles can't hear levels of up to 5%. This is based on testing I have done myself utilizing 'My Disc' From Sheffield Labs. Try the test yourself, it's quite enlightening.

Geeze Waller...7 of 9 consecutive posts...Not bad. [img]tongue.gif[/img]

How can a source disc determine the distortion you are hearing from a transducer?

Perhaps you can't detect below 5%, because you already have that level in your test speaker.

I used to do a demo back when Altec Lansing still did the Voice of the Highway's.
They were rated at less than 1% THD at 1 watt.
Standing in front of the right speaker on the display, the Altecs were the only one that you could hear the left speaker distinctly.

I A/B'd against Zero Point, Polk, Macrom, Oz, etc.

My theory was that the low distortion of the Altecs, was less than the percentage of difference between the left and right channels of an average source disc, allowing the difference to be heard.

I figured that the small difference in location cues was "lost" in the distortion produced by the other speakers.
The Altecs are still my favorite components of all time. Too bad about the fire.