Pass Labs versus Jeff Rowland, Audio Research


As I am considering replacing my trusty pair of Jeff Rowland 7M monoblocks, feeding a pair of MagnePan IIIAs, I am looking at both the current Jeff Rowland lineup, as well as at the latest incarnation of the Pass Labs X series, dubbed the X.5 series, and some Audio Research models.

In the Rowland lineup I am considering the 501 monoblocks, or the 302 stereo amp, while I have already determined first hand that the smaller 201 monoblocks do not drive the MagnePan IIIA pair adequately.

In the Pass Labs lineup I will consider the X-250.5 (already released), the X-350.5 (just out of engineering), and the upcoming X-600.5.

From Audio Research I already discarded the otherwise extremely lovely VT100 as just slightly underpowered for the Maggies, but will consider the VT200 stereo, the new VSM220 monoblocks, as well as the VTM200 monoblocks.

The rest of my system consists of EAD T1000 CD transport and EAD DSP7000 Mk3 (these likely to be replaced by Esoteric X-01, and an Audio Research LS2B.
I most listen to classical, and within it more to solos and small ensambles than to large orchestra.

I'd value all opinions! In particular any comments concerning the relative merits of the newest Pass amps vs the other brands would be very appreciated.
According to Pass and to those dealers that have already the new X.5 models, these new boxes have a more refined and detailed sound than the old X models, and a fuller fleshed-out midrange. But, how do they truly stack up to Rowland and Audio Research?
guidocorona
Sweetness, delicacy and overall glow were all there, Pass is of the highest order in SS amps...dynamics were limited with the older model with his very hard to drive Apogees. He moved on to an digital amp..first a 250 watt (I think) eAR and is now using H20 mono-block digital amps. I guess these are also 250 watts per and are very tube-like with SS power quality for the bass.

I am still using my old Krell Ksa-250 to drive my Apogee Duetta Signatures so take my input for what I read...I have tried none of these amps with my speakers.

My understanding is that Jeff Rowland also has a digital amp out which also uses this same B&O ICE technology in it's design.

Dave
That's me sogood is talking about. I like what I have now, H2O Signature monos, so much more, it ain't funny.
Thank you so much Dave and Muralman1 for the input.
What is the efficiency of the Apogee Duetta and their impedance?
Please tell me more about the H20 Signature.
I have auditioned the Rowland 201 monoblocks, rated at 250W, also based on the B&O chipset. They sound very magical in many ways, but they did flatten out the soundstage at the minimum excitement while driving MagnePan 3.6, which are just slightly more efficient than mine.
are your model 7 the latest specification? If not inquire about potential upgrades from Rowland
Guidocorona

My Duetta Sig's are in line with your speakers at 4ohms and dipping. Muralman1 has the Apogee Scintilla at 1ohm...a real amp eater that was a load for the Pass.

As I stated, I have not tried any of these digital amps. My old Krell Ksa-250's power supply is much more than the big pass also but I am going to give the H20 digital amp a listen in my system in the near future...not enough H20's for trial at this time in mono-block if any? Maybe Muralman1 can shine some light on that as he owns a pair and knows the designer.

Dave