What amp are you using with your Zu Essences?

I have a pair of Essence and have just transitioned to tubes from solid state-- actually, I'm still in transition as I won't have my pre until the third week of February.

Current setup:

Zu Essence

Manley 300B SE/PP monoblocks (11 wpc SET; 24wpc PP); SET at 0-2dB negative feedback; PP at 1-3 dB negative feedback.

Sony ES receiver serving as a temporary pre-- being replaced with a Manley 300B pre.

Sony HAR-D1000 cd

Zu Libtech speaker cable
Zu Gede interconnects to the amps
Zebra Cables custom interconnects from CD to pre
Zu Mother power cords

11 wpc in SET mode plays LOUD in my room 12*16*8. The sound is exceptionally liquid, dynamic, and three-dimensional. This should improve dramatically when I use a better pre, but it's pretty fantastic now.

I have also paired the Essence with the Sony ES Receiver, a Cambridge 340A integrated, and a Rega Elicit integrated. Best sound was obviously the Elicit, but the 340A put in a strong showing.

Some points about the Essence with tubes: the top-end is very balanced and well integrated with the FRD. The impedance of the ribbon tweeter seems to interact with the tube amp to shelve the response down slightly to better intergrate with the rest of the frequency spectrum. Bass is full and weighty. In-room response is in the high 20's in my room.

Some points about the Essence with solid-state: the 340A (roughly 40wpc) has more than enough power to be speedy and exceptionally dynamic. The Elicit has a little more headroom, but the difference in power and drive is not noticeable. The 340A is slightly more punchy at the expense of smoothness, lack of grain, and the flow of the Elcit. Overall, an amp with the characteristics of the Elicit is a better match in the solid-state world. Placement can be tricky with solid-state as I found the treble response to be a little "hot". I don't want to overstate this as it was easy to deal with, but others (in the Zu camp) have different opinions on the magnitude of this issue. I found it easy to compensate for this by using different interconnects and speaker cables (annealed copper) from Zebra cables. This smoothed the response nicely. In addition, experimenting with toe-in so that the tweeter outputs cross behind the listening position on the midpoint of the rear wall smoothed this.

Overall, 11 SET wpc really lights up the Essence in my room. A small but noticeable difference from 24 PP wpc-- better grip in the bass, slightly more dynamic, slightly less liquid.

PMB

Phil, the Zu guru highly recommends the Quad II's, Quad II-40's, and Quad II-80's. If I recall correctly, the all-out winner is supposed to be SET using 845 tubes.

I have also heard that EL-84 based amps do well.

I like my Manley's, but it would be nice to have the funds to compare.

PMB

FWIW, the Essence ribbon tweeter output is "aggressive" with solid state gear, but nothing that can't be accommodated/resolved through careful (small) changes in positioning. I found that toe-in so that the tweeter output intersected on the rear wall behind the listening position minimized this in my room. Listening height plays into this as well.

That said, all of this went away with tubes. The impedance curve of the tweeter shelves down the output just a little on my Manleys. My Manleys are a very good match for the Essence albeit a pricey one at the new list price.

PMB

Just thought I would chime in one more time. I have about 150 hours in on my Manley Steelhead which is partnered with my Manley 300B amps-- replacing the receiver that was performing stand-in until the Steelhead arrived. After replacing a tube in the 300B that was apparently functioning but not at peak and inserting the Steelhead into the mix, I couldn't be happier with the sound.

With the Steelhead/300B combo, the Essence throws a huge wall-to-wall soundstage that starts slightly in front of the speakers and extends back through the rear wall of my room. In SET mode, they are absolutely stunning on small ensemble music or acoustic. It's pretty exciting to have Tori Amos, Ani DiFranco, and Van Morrison lifesize and in 3D in the room. Plus, if I want slightly better dynamics, I just switch the 300B's into PP mode. In PP, the 300B's have all the drive that the Essence will ever need in my room.

Upon final assessment, wihtout the option of switching between SET and PP, I would recommend at least 15 watts of SET or PP power to really experience all of the dynamics of which the Essence is capable. 24 watts of PP 300B power is more than sufficient. If you are not listening at moderately high to high listening levels on large-scale classical (e.g. Mahler) or on something like electronica (e.g. Massive Attack) then less watts would be just fine.

Enjoy,

PMB