Overview:
The D2608/913000 is a tweeter from the ScanSpeak Discovery series. It’s essentially the same tweeter as the famous Peerless “HDS” tweeter, but nowadays its built by ScanSpeak . It plays in a division higher tan the other “Discovery” tweeters, almost like the “Revelator” or “Illuminator” tweeter series.
It offers a very sturdy build quality with a metal faceplate and a double magnet system.
It uses ferrofluid combined with a fully vented motor system for low compression and it has a fairly low resonance frequency. This is a low distortion tweeter an can be used as low as 1500Hz.
ScanSpeak Spec sheet: D2608/913000
T/S Parameters:
About 10% higher fs than official spec sheets. Not a perfect match between the two samples, but within limits.
Impedance:
Free air impedance measurement:
Sample 1 = Green
Sample 2 = Blue
Thanks to ferrofluid in the magnetic gap, a shallow impedance peak around fs. The two sample are a reasonable close match.
Frequency:
Frequency measurement conditions:
The tweeter is measured mounted on a 14 liter Dayton Audio enclosure (PartsExpress part #302-721) baffle with the following conditions:
Baffle size (WxH): 21,59×35,56cm (8,5″x14″)
Driver position: Mounted on center-line with driver unit center 8cm from the top of the baffle.
Mic position: 1m distance, on tweeter-axis.
Smoothing: No smoothing applied.
Not a perfect match between the two samples in the higher octaves. Sample 2 has a broad dip around 15kHz, but instead has a frequency response up to 30kHz!
In the cross-over region they measure essentially the same.
Sample 1
0deg = Blue
15deg = Red
22.5deg = Green
Baffle diffraction around 3.5kHz which as expected flattens out off-axis. Nice extended frequency response and off-axis dispersion.
Sample 1
0deg = Blue
15deg = Red
30deg = Green
Sample 1
0deg = Blue
30deg = Red
45deg = Green
Even at 45deg off-axis this tweeter reaches 15kHz!
Distortion:
The distortion measurements are done in near-field and the amplifier output level was adjusted for the driver unit so that the fundamental is 85dB at 1m and 90dB at 1m. This setting simulates normal to medium-high listening levels.
- Tweeter near-field measurement at 10cm
- Frequency Range: 500-10000Hz
- Baffle size WxH: 21,59×35,56cm (8,5×14″)
Sample1 – 85dB at 1m
Sample2 – 85dB at 1m
Sample1 – 90dB at 1m
Sample2 – 90dB at 1m
Overall very low distortion throughout the frequency range. This tweeter can be crossed-over as low as 1.5kHz, without distortion becomes an issue.