anyone here experience with Jeff Rowland Model 102

I have one for a while - one of the first built. It uses the same Bang and Olufsen modules (200ASC) as Bel Canto's S300 and M300. S300 is rated 300W at 4 Ohm because it is measured at 10% distortion. The module is identical. One of the S300 problems was resonating cabinet (improvement with antiresonant feet). Rowland is carved in the solid block of aluminium. Soundwise it is much better than my previous integrated (good one). It has a lot of energy and clarity in the mids and highs. Very clean sound. Bass control is very good and makes sound a little too lean. I changed speaker cables from thin sounding AQ Indigo to Acoustic Zen Satori shotgun and it improved lower midrange. Voices sound much fuller now. It is really analog amplifier with PWM output. It is based on Karsten Nielsen analog oscillator - I read a little a bit of his doctorate work on Internet (University of Denmark).

Is this the Model 102 you are referring to ?

Yes. It is Jeff Rowland Model 102 (2x100W@8Ohm, 2x200W@4Ohm). I bought it few months ago. Each amplifier board inside has its own compartment and has switching power supply built in - pretty much like two monoblocks with the common power cord. It has the smallest and the latest of B&O modules (200ASC). B&O was so impressed with Karsten Nielsen MS work that they sponsored his doctorate, gave him company stocks (first time to private person in over 70 years of B&O history) and created subsidary company ICEPower making him a president.

I mentioned S300 only because there are no reviews of the Rowland's 102 and Bel Canto S300 has at least two. I wonder if Rowland made any changes to factory modules since it normally voids B&O warranty. B&O does not sell them to public and the minimum quantity is one crate (790 units). They might have some design (changes) agreement. People at B&O are sound fanatics and probably squeezed all they could from the design. There are amps (Channel Island) based on Hypex modules available to public if you want to build yourself. Rowland has 5 years warranty.

Kijanki,

thanks for post.

out of curiosity, what pre-amp are you using with these ?

Are you using the balanced interconnect for these amps ?

What speakers have you driven them with ?

Appreciate your inputs.

I am using Benchmark DAC1 (has only digital inputs and built in volume control) with 0.5m AQ King Cobra XLR. Drive Paradigm Studio 60v2 (with improved Xovers)using 6' Acoustic Zen Satori Shotgun. Paradigms are the weakest link now. "Digital" amps are in a sense not involving - as my DAC is not involving (appears at first). Benchmark is designed to supress (-40dB) jitter. Jitter from transport causes small amount of side bands (about -85dB at 3ns) very audible since not harmonically related to base frequency. Lack of "fuzz" in the sound made at first impression of missing instruments - sounded too clean (still very dynamic). Similar thing with Rowland - strong highs but no glare (no intermodulation distortions common in SS amps) - very smooth and clean. It is very good amp for the money. Older bad sounding "D" class amps were digitizing with limited resolution. ICEpower is purely analog with unlimited resolution. Very high damping factor droping to 1000@1kHz makes tube amps with poor damping sound blooming at the midrange. Tubes sound nice but similar to wearing yellow sunglasses - nice view but not real (again who knows what is real?). I had to tame Paradigms metal dome tweeter wit L-Pad (and upgrade Xover)- not because of glare from CD but from HDTV (toslink). Now is a little opaque with CD but warm and nice. 200ASC module has only about 1 degree phase shift difference 100Hz-20kHz. Phase changes between channels are probably small fraction of a degree - resulting in nice soundstage with instuments clearly positioned and more of the 3D quality. Hope it helps.

Thanks for the insight Kijanki.

Before you settled on the Model 102, did you give the PS Audio digital amps a listen ?

A similar model called PS Audio Trio A100 $1000 seems to exist. I heard one recently and was quite impressed.

To be frank I did not listen to any of the components I currently have or others. I read tons of reviews and user opinions instead. I decided that each component is dependand on the others and listening to only one is not useful. I started picking selection starting from the source and after almost buying used Ayre CD player I decided I want to have my TV and DVD also connected by digital interface. I bought Sony DVD player and Benchmark DAC1. That was easy choice (saved a lot of money on transport+DVD sound). AQ King Cobra was known before a Python and was expensive. AQ in order to be competitive moved production to China and slashed the price changing cables name. Now you can buy used one (0.5m) for $50 (no brainer). I intended to buy Bel Canto S300 for its glowing reviews but Rowland has great reputation (in 20 years released only great products) and it was cheaper then (forced Bel Canto to lower price). Satori Shotgun is expensive $1100 (bought used) but is probably the best choice for lean sounding system (slight lower midrange emphasis). Replacing everything with fairly neutral sounding components makes life easier in future. Now I have time to research speakers. Acoustic Zen Adagio with underhung speakers and ribon tweeters is one of possibilities.

PS Audio had good reviews in Stereophile - at least integrated amp but is over my price range. Red Dragon Leviathan (based on 1kW ICEPower) is one of the better digital amps as well as one called H2O - both well above my spending limits. Rowland's 201 and 501 monoblocks are great but again expensive.

Robert Lee the founder of Acoustic Zen presented his Adagio speakers this year connected by his cables (of course) to Red Dragon amps. He is perfectionist (Zen Buddist)and he thinks Red Dragon is the best.

Warning about didital amps - they often require very long break-in. My Rowland started sounding decent after 200hrs but after 400hrs sounded fuller. It is still changing (I bought it in April). It is releated to glues and varnishes on inductors and transformers that are drying long time in cool running amp.

Kijanki, thanks for the info.

Wow, that is a long break in time!!

Is it also true that the amp can take a wide variety of fluctuations and still sound good unlike conventional amps ?

I've never heard of rowland gears but judging from the way they look and the way they are reviewed, they seem well reputed and well made.

In your opinion, in terms of durability how do you feel about these digital amps ?

Thanks again.

Noli

Thanks for the user post notes, which were all very useful and helpful.

Spkrplus,

I ended-up with Hyperions HPS-938 (6 month dealer demo for $3K). Amazing speakers from less than amazing company (if they still exist). Combination of revealing Benchmark DAC1 with Rowland 102 driving Paradigm Studio/60 (metal dome tweeters) was unbearable. Replacing/integrating tweeters with Morel Spreme 110 (soft dome) failed - wasted time and money. Hyperions are warm, revealing and never forward - perfect fit.