I can speak from experience on both the Harbeth M-40.1's and the Aesthetix Calypso preamp.
The Harbeth M-40.1's have a very flat impedance curve and are 6 ohm nominal... so your PASS amps would be more than powerful enough for them. I've driven them with tube amps ranging from 3o watts to 75 watts and they sounded great with all of them.
Verity Parsifal Ovations are also highly regarded and can be found used for around $10K. They come packaged in flight cases, so they travel well.
If you are considering Tannoy, I'd be looking at Kensington SE's.
The Calypso preamp is a dependable, high value preamp that responds very well to tube rolling. You can find them for around $2,400 used... just need to spend another $400 on good NOS tubes and you have a great preamp.
Atma Sphere & Lamm would also be on my short list. Rogue would not be on my radar when it comes to preamps.
The Harbeth M-40.1's have a very flat impedance curve and are 6 ohm nominal... so your PASS amps would be more than powerful enough for them. I've driven them with tube amps ranging from 3o watts to 75 watts and they sounded great with all of them.
Verity Parsifal Ovations are also highly regarded and can be found used for around $10K. They come packaged in flight cases, so they travel well.
If you are considering Tannoy, I'd be looking at Kensington SE's.
The Calypso preamp is a dependable, high value preamp that responds very well to tube rolling. You can find them for around $2,400 used... just need to spend another $400 on good NOS tubes and you have a great preamp.
Atma Sphere & Lamm would also be on my short list. Rogue would not be on my radar when it comes to preamps.