Is this distortion acceptable on a 93 dB tweeter?

[jawen]

 

[markbakk]

Well, our ears can live with quite some HD, certainly the even ones. So I think it depends, but a lot of people wouldn’t know the difference.

 

[jawen]

Well, our ears can live with quite some HD, certainly the even ones. So I think it depends, but a lot of people wouldn’t know the difference.

Yes understand, and dont know if the dist is from "good" or "bad" harmonics.

Its the Sica LP 90.28/N92 TW i maby are little interested in.

https://www.dibirama.it/home-page/tweeter/377-sica-lp90-28-n92-tw-tweeter-1-1-8-ohm-120-wmax.html

​

 

[mattstat]

If accurate and the SPL for the distortion test is referenced to 1 meter, it's more distortion than I would want. You're basically in the direct radiator sensitivity range. You should be able to find a waveguided tweeter with much lower distortion than that and more output.

If it was a horn-loaded compression driver with much higher sensitivity, it would be more understandable.

Is that distortion data provided by the manufacturer or a third party? It's not easy to take accurate distortion measurements in a home environment, and that graph looks very smooth. Makes me suspicious of the numbers.

 

[jawen]

a third party?

https://www.dibirama.it/home-page/tweeter/377-sica-lp90-28-n92-tw-tweeter-1-1-8-ohm-120-wmax.html

 

[mattstat]

The Zaph tweeter mishmash has a lot of data for many tweeters. It's a little dated at this point, but gives a good idea what a typical dome's distortion profile looks like.

http://www.zaphaudio.com/tweetermishmash/

http://www.zaphaudio.com/tweetermishmash/compare.html

 

[weltersys]

I wouldn't make any "acceptability" statements about distortion without knowing the test measurement distance, your expected listening distance, and desired SPL at that distance.

Yes understand, and dont know if the dist is from "good" or "bad" harmonics.

Which harmonics do you consider "good" ? 😉

 

[jawen]

The Zaph tweeter mishmash has a lot of data for many tweeters. It's a little dated at this point, but gives a good idea what a typical dome's distortion profile looks like.

Im bad at interpret this type of measurements, but this is from a guy in Czech Republic

dimensions of the board approximately 38cm x 23cm. In height, the converter is placed in the middle and 8 cm from the top edge. Rounding around the perimeter 2.5cm

 

[jawen]

Which harmonics do you consider "good" ? 😉

Hahaha, all that make my ear´s dance and not to wrinkle oneself 😉 🥳

 

[mattstat]

this is from a guy in Czech Republic

That's more like what I would expect. The levels and the character seem more typical of a dome tweeter.

 

[stv]

Some more measurements of this tweeter on the german hifi-selbstbau site, including distortion measurement (scroll down to "klirrfaktor" or click here):

https://www.hifi-selbstbau.de/index.php/hsb-datenblaetter/hocht/lp9028n92tw-z009160

 

[tktran303]

Dibirama's distortion measurements can only be compared with dibirama's.

Zaph's can only be compared with Zaphs.

The distortion measured depends on the equipment that is used- that is- it's a measurement of the whole signal chain, including the microphone-

Reference:
Difference microphones have their differing amounts of self noise and distortion

 

[looneybomber]

The distortion looks uncharacteristically consistent. There’s almost no undulations. Logarithmic plotting would help, but it would still be real consistent across the frequency range. Perhaps it has to do with how the person took the distortion measurements.

 

[Sonce]

Pity the dibirama measurements are THD only, without separate graphs of H2 and H3.
Unless H2 is too high, H3 is the only measurement we should be concerned about. Higher harmonics (H4, H5, ...) must be much, much smaller.

 

[jawen]

Some more measurements of this tweeter on the german hifi-selbstbau site, including distortion measurement (scroll down to "klirrfaktor" or click here):

Thank you for link´s
That is the older version of the tweeter, but don´t know if the newer one just had the X over the cone gone, or if had small changes inside also.

Maby worthy a diy in the future!

 

[kouiky]

View attachment 1440663
View attachment 1440662

Might I ask what distance the distortion measurements in the bottom graph were taken at? The level of distortion seems excessive and it might even be the gain structure introducing distortion in the signal chain.

I suggest using less smoothing and maybe plotting the individual harmonics for comparison against the fundamental.

 

[5th element]

As far as I can see it's the same distortion as the top graph but shown in a different way. Note that the scale on the left shows each major division is 20dB.

 

[duvixan]

Maybe consider the LP110.28 instead.
It is used in Gold Note and Xavian speakers.

 

[jawen]

Might I ask what distance the distortion measurements in the bottom graph were taken at?

Measurements are from Dibirama Italy, a serious, recognized talented group of hifi lovers.
Don´t know their measurement (technical terms)

https://www.dibirama.it/home-page/tweeter/377-sica-lp90-28-n92-tw-tweeter-1-1-8-ohm-120-wmax.html

 

[jawen]

Maybe consider the LP110.28 instead.
It is used in Gold Note and Xavian speakers.

The tweeter for sale was a pair of LP 90 new in box for about 45% of "regular price"