Test BlieSMa 34 mm Beryllium dome, T34B-4
Copyright 2018 © Troels Gravesen


Available from BlieSMa, Germany, an extension of the dome tweeter product range by a 34 mm Beryllium version of the tweeter tested a few months ago. Read here and get background info.
Price will be around 390 EUR + VAT.
Go to BlieSMa website.

Based on the measurements below and simulation of the tweeter with various mid-bass drivers, I'm looking forward to implementing these tweeters in future designs.


Tweeters come with impeccable finish.

Download T34B-4 specs here.

 

 


Frequency response of two tweeters on a 60 x 100 cm baffle.
As can be seen the break-up node comes around 33 kHz, some 4 kHz higher than the AlMg variant.

 


Impedance of the two tweeters, Fs ~800 Hz on average.

 


T34A-4 (green and orange) compared to T34B-4 (red and yellow).
As can be seen a very flat response and some 2-3 dB higher sensitivity of the Be dome.

 


CSD of unit 1.

 


CSD of unit 2. In both cases a very clean performance.

 


2nd order distortion measured at input equivalent to 104, 98 and 92 dB @ 1 meter distance.
2nd harm.: Green, blue and light blue.
These tweeters appears suitable for a very low point of crossover between 1 and 2 kHz, thus two-ways from 8" drivers should be possible.

 


3rd harm. distortion at same levels. As usual 3rd harm. is very low.

 


Horizontal dispersion at 0, 10, 20, 30 and 40 deg. off-axis.

 


Click images to view large.