Test ScanSpeak D3004/660000 vs ScanSpeak D2608/913000
Copyright 2018 © Troels Gravesen

        
Left/middle: D3004/660000. Right: D2608/913000

All measurements were performed at 0.25 meter distance, normalised for 1 meter/2.8V. Baffle 60 x 100 cm.
Drivers flush-mounted.

The D2608/913000 tweeter is a smaller tweeter compared to D3004/660000, thus may not be used as low as the 6600 tweeter.
With regard to distortion there are no significant differences between the two tweeters. Both display very low distortion down to 1 kHz.
9130 settles faster from an impulse response, which can be seen from the step response.
9130 has a cleaner cumulative spectral decay compared to 6600, although not in an area that matters in usual applications.

D3004/660000 tweeter measurements

Left: Unit 1, frequency response. Right: Unit 2, frequency response.

Left: Unit 1, distortion test. Green = 2nd harm., blue = 3rd harm. Right: Unit 2.

Left: Unit 1, cumulative spectral decay. Right: Unit 2, cumulative spectral decay.

Left: Unit 1, impulse response. Right: Unit 1, step response.

D2608/913000 tweeter measurements

Left: Unit 1, frequency response. Right: Unit 2, frequency response.

Left: Unit 1, distortion test. Green = 2nd harm., blue = 3rd harm. Right: Unit 2.

Left: Unit 1, cumulative spectral decay. Right: Unit 2, cumulative spectral decay.

Left: Unit 1, impulse response. Right: Unit 1, step response.