One pair of Ribbon Super Tweeters, made by speaker builder James Strasser, who typically sells his wares on Audio Asylum only. He's got no website; he's a true boutique builder.
Spec up to 60kHz, with resistors included to attenuate to suit:
In pairs: 0.5V, 1.0V, 1.5V, 1.8V
They make a tremendous difference in the 'fullness' of your sound, no matter the speakers.
The drawback is that they typically have to run off of the speaker terminals. With solid state amps this is not a problem, but I've run into problems with tube amps. You an also use them in a bi-amp configuration.
Beautifully made, solid terminals and very clean looking.
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