Harmonic Distortion for the Zaph Meister...

[paul_n_oneal]

I just noticed that on the tweeter mismash you only go out to 10k. Is this indicative that at above 10k distortion is not an issue?

paul

[bryanjackson]

At 10k, 2nd order distortion is at 20k, 3rd order is at 30k. It's improbable that you'd hear the 20k, neigh impossible you'd hear the 30k.

[jkrutke]

> At 10k, 2nd order distortion is at 20k, 3rd
> order is at 30k. It's improbable that you'd
> hear the 20k, neigh impossible you'd hear
> the 30k.

There's also the issue that with my sound card's bitrate limitation, I can only measure the 5th order harmonic up to 48kHz. If you look closely you can see it drop off at 9.6kHz in every measurement because that's where the data stops. SE will only let me run sweeps so high.

Note that some of the tall order harmonic distortion will propagate back into intermodulation distortion lower in frequency. That said, IMD above 10kHz is also unimportant as the ability to discern detail disappears at the highest frequencies.

The most important part of a tweeter's distortion performance is always going to be it's low end as this is where the distortion is most audible. I'm just going to pull a guess out of my **** here, but I'd say that 90% of the performance that affects a tweeter's audible character happens between the crossover point and 4kHz. If you cross over high enough, there's really no point in using any tweeter more expensive than a $5 Dayton neo. Spend that extra money on the woofer. Here's where fans of ribbon tweeters go wild and I go into hiding for a month.


(Originally posted by: jkrutke)

[paul_n_oneal]

> There's also the issue that with my sound
> card's bitrate limitation, I can only
> measure the 5th order harmonic up to 48kHz.
> If you look closely you can see it drop off
> at 9.6kHz in every measurement because
> that's where the data stops. SE will only
> let me run sweeps so high.

> Note that some of the tall order harmonic
> distortion will propagate back into
> intermodulation distortion lower in
> frequency. That said, IMD above 10kHz is
> also unimportant as the ability to discern
> detail disappears at the highest
> frequencies.

> The most important part of a tweeter's
> distortion performance is always going to be
> it's low end as this is where the distortion
> is most audible. I'm just going to pull a
> guess out of my **** here, but I'd say that
> 90% of the performance that affects a
> tweeter's audible character happens between
> the crossover point and 4kHz. If you cross
> over high enough, there's really no point in
> using any tweeter more expensive than a $5
> Dayton neo. Spend that extra money on the
> woofer. Here's where fans of ribbon tweeters
> go wild and I go into hiding for a month.

Not by me. That makes perfect sense. The reason asking has to do with the Neo as I plan to use it to fill in the top octave of my latest design crossed around 10khz. I still haven't found out how loud it can go though. Any idea? It say's 15watts. So I figure 106db max before meltdown?

Paul

[Pete Schumacher ®]

> Not by me. That makes perfect sense. The
> reason asking has to do with the Neo as I
> plan to use it to fill in the top octave of
> my latest design crossed around 10khz. I
> still haven't found out how loud it can go
> though. Any idea? It say's 15watts. So I
> figure 106db max before meltdown?

> Paul

It'll definitely go "louder" than that on short passages. 15 WRMS is a LOT of tweeter power, and you'll only be hitting those levels rarely. I wouldn't worry about it Paul. That last octave has at most 10% of the total music power. Your typical 500W amp will provide about 100W of music power, meaning the tweeter will likely see no more than 10 WRMS long term.

[paul_n_oneal]

> It'll definitely go "louder" than
> that on short passages. 15 WRMS is a LOT of
> tweeter power, and you'll only be hitting
> those levels rarely. I wouldn't worry about
> it Paul. That last octave has at most 10% of
> the total music power. Your typical 500W amp
> will provide about 100W of music power,
> meaning the tweeter will likely see no more
> than 10 WRMS long term.

Thanks Pete, no more worries.

Paul