Sub-woofer fast enough for Horns?

Yea - give the Martin Logan Depth I a try - designed to match the speed of Electrostatics.

I have one myself for my very fast mains (they are not horns but have tricks done like lining with 1/4 copper to decrease resonance and increase speed) and their speed is fine. The only issue is, as with any subwoofer, integrating it into the mains seamlessly. I personally only ever use it for HT because the music I listen to doesn't have much low bass. But when I do engage it for music, while I generally prefer it engaged, you can detect some anomalies caused by the fact its not seamlessly integrated - its speed however is fine.

Thank

Bob_reynolds wrote 'Can anyone explain what "fast" means? What does "slow" sound like?'

Well speed in the case of a sub-woofer is obviously not an apt description since they are concerned with frequencies that have no 'quickness' at all. In that case its the impression you get with a low distortion subwoffer that is not blurred by things like cabinet resonances and has other measures like servo feedback to ensure better tracking.

With regard to full range speakers its the ability to hear nuances you might not otherwise hear. In electrostatics for example due to the light diaphragm material they have it can accelerate and decelerate quickly. In my speakers, which are conventional, its due to them being lined with 1/4 inch copper that reduces resonances that mask detail. In horns its due to their acoustic impedance matching.

Basically is the impression you get of detail jumping out at you without blurring - you say its fast.

Thanks
Bill