Best Integrated amp for Wilson Audio Sasha


Thinking of the Gryphon Diablo, Acuphase E560, Passlab Nt-150 or Dartzeel 8550 for the Sasha. Any recommendation from those using this speaker?
hifinuts
In fact, you would absolutely not want a "higher power" amp, whether it be a power amp or integrated amp, if you have reasonably efficient speakers, and certainly not on a 91+ db. efficient speaker like the Sasha, as the vast majority of such amps use a lot of global feedback to control the circuit, as well as numerous output devices (i.e., numerous transistors or power tubes) to achieve high power. Feedback imparts a muted, closed-in, two-dimensional sound, and the numerous output devices reduce transparency and just generally muck up the sound on high-resolution systems. In this regard, it is frequently said, with good reason, that the lowest powered amp in a line of amplifiers is the best sounding one - the simpler the circuit, the better.

The new Rowland 625, the Ayre amps, and the darTZeel amps use no global feedback and none has a rated output of more than 300 watts/channel into 8 Ohms. Most Pass amps do not use any global feedback, and a few models have only three gain stages. The darTZeel stereo amp uses only a single pair of transistors per channel.

If you have really inefficient speakers (84 db. or less), if your system is in a really big room, or if you listen primarily to disco at 120+ decibels, then there may be a compelling reason to buy a high-powered (400+ watts per channel) amp. If, however, you're running efficient speakers like Sashas and have a reasonably normal room, high wattage is not what you want.
I was just listening to a pair of very well set up Sashas last week. The electronics were the Audio Research Signature Anniversary line, specifically powered by their 110 wpc VS115 power amp, a huge all tube beast rated at 110 wpc. All cabling was a high level (but not top level) Transparent.

The sound was stunning in every way. In fact, I've been going to the Seattle Symphony quite a bit lately, and this ARC/Transparent/Sasha combo had an immediacy and ability to energize the room and air much like a live performance. It's one of the best illusions of the more elusive aspects of live performance that I've heard.

Not that it's pocket change, but at $12K that ARC VS115 power amp is an absolute stunner powering the Sashas.
I used to on the WP/7s and drove them with a Spectron MIIISE amp and VTL TL7.5 preamp. I happily replaced/upgraded this combo to the APL UA-S4 integrated which is a single gain stage amp with extremely pure tone, which I still own although Ive sold the Wilsons.
JTinn- I looked on the Dart website and there are no specs or mainstream reviews, so I will defer to you.

Raquel- Sashas efficiency is misleading. They spend most of there time below 4 ohms with some tough phase angles---this isn't a 90db flat 8ohm impedance speaker---and not near as easy to drive as higher end Wilsons.
Dear Keith:

The darTZeel integrated was subject to a full review by Stereophile - here is the link: http://www.stereophile.com/integratedamps/dartzeel_cth-8550_integrated_amplifier/index.html

The Sasha was also reviewed by Stereophile and subject to Atkinson's normal suite of measurements - its impedance characteristics are well known:http://www.stereophile.com/content/wilson-audio-sasha-wp-loudspeaker-measurements

In fact, all of the WattPuppies, and most other Wilsons, drop to or below 3 Ohms in the bass and feature moderately steep phase angles.