These two SB Acoustics tweeters are the first in a series of new driver measurements I will publish on the website. I will probably use some of them in future moderately priced loudspeaker designs.
Detailed measurement data:
SB Acoustics SB26STAC-C000-4
SB Acoustics SB26STCN-C000-4
SB26STAC vs. SB26STCN comparison:
Build quality and looks:
The SB26STAC with its aluminium faceplates both looks and feels more robust than the SB26STCN plastic faceplate and its small Neodymium magnet. At this price level, 44$ for the SB26STAC and 35$ for the SB26STCN, they both seem to be very nicely built.
Impedance:
(click on picture to zoom)
Green = SB26STAC
Blue = SB26STCN
The SB26STAC has a resonance frequency of 750Hz and the SB26STCN about 170Hz at 920Hz. Both are very close to the manufacturer specification. The Impedance profile is very similar from 2.5kHz and up.
Frequency:
(click on picture to zoom)
Left: On-axis
Right: 15deg off-axis
Blue = SB26STAC
Red = SB26STCN
Note! SPL is normalized to roughly the same sensitivity
The tweeters have almost identical frequency response curves. The SB26STCN has about 0.5-1dB higher sensitivity than the SB26STAC.
Distortion:
(click on picture to zoom)
95dB @ 1m
Left = SB26STAC
Right = SB26STCN
The SB26STAC has lower distortion than the SB26STCN. A qualified guess is that the SB26STAC can be crossed over lower, at least 500Hz or more than the SB26STCN.
Summary:
The SB26STAC would fit nicely with mid-woofers up to 6.5” and the SB26STCN would fit nicely in M-T-M configurations or in small compact mini monitors with a mid-woofer size up to 5”
Based on the measurements performance I consider both these tweeters to be of high value and with a high performance/price ratio. It will be interesting to see if they also sonically turn out to be as good as the measurements.