Test:
ScanSpeak Be dome D3004/604010
Copyright 2015 © Troels Gravesen

Last year I made a pair of minis for the ScanSpeak exhibition at the Munich HighEnd show. These minis featured the prototypes of this D3004/604010 beryllium dome tweeter. Here one year later, ScanSpeak has finally launched the tweeter with a slightly modified grille incorporating a small phase plate in front of the dome, presumably smoothing the 15-20 kHz range.
The tweeter also comes in a car version with reduced rear chamber depth.

Now, these tweeters sell at 318 EUR/each incl. VAT compared to 444 EUR for the D3004/664000 and 475 EUR for the D2908/714000. Hmm... quite some money to be saved. For comparison, check out my tests of the 6640 and 7140 Be domes here.
Generally we can now get a high-quality Be dome at the same price as state of the art soft domes like the 7100 ring radiator.

To cut a long story short, I can't wait to incorporate these domes in the Illuminator-5 and AudioTechnology 3-Way Classic. Based on the measurements below, I would be very surprised if they don't perform as well as their more expensive siblings.

The domes feature a metal face plate, or should we say mounting ring. All-metal non-resonant rear chamber. Only thing to take care of is the soldering tags. These are for good reason mounted on plastic sockets and just don't add too much heat from your solder iron.
Only thing I miss here is ScanSpeak supplying 6 black screws fitting the mounting holes. Not easy to find some that also look good!
 

Click images to view large.

Download specs here.

Measurements

Above the basics. To the left SPL @ 1 meter, 2.8 volt for unit I and II. Quite a matched pair! Sensitivity is around 91-92 dB where SS conservatively rate them as 90.2 dB/2.8V/1 meter.
To the right impedance curves of unit I and II. With the deep rear chamber SS can maintain an Fs of 500 Hz, even a little below.

Above step response of unit I (left) and unit II (right).

Above cumulative spectral decay of unit I (left) and unit II (right).
These may not be as quite as clean as the 7140 tweeter, but better than the 6640 at the low range.
By any standard an excellent performance.

Dispersion @ 0, 10, 20, 30 and 40 deg off-axis.

Above distortion measured at an input equal to an SPL of 92 dB @ 1 meter distance.
This is as good as any of the other SS Be domes.

Above distortion measured at an input equal to an SPL of 98 dB @ 1 meter distance.
These domes really go low with insignificant distortion and a 12 dB crossover at 2 kHz looks like a piece of cake!

Final comment:

As mentioned above, the terminal are stuck into a plastic socket and if you like me use the tweeters for multible applications, secure the terminal sockets with some Araldite. Use a syringe with a large needle, cut the needle to 1 cm and inject glue below the terminals as seen on photo. Still, solder fast and with as little heat as possible.