Rowland Model 6 monoblocks - my thoughts


I promised John (Jmcgrogan2), that I would share my thoughts on the Jeff Rowland Model 6 amps that I purchased from him. If you are interested...read on!

Some background: I have always been a tube guy. In fact this Rowland is my first solid state amp. From Conrad Johnson, Cary Audio, VTL, Audio Research, and Sonic Frontiers, I've had some damn fine tube gear in my house! As is so often the case with this hobby, I took a trip on the dreaded audio avalanche; buying, selling, trading, and testing various components. Each time, convincing myself that it just wasn't right. Always, that little voice kept pushing...just buy "Brand X" cable, or "Brand Y" isolation feet, and use "Brand Z" vintage tubes, and the sound will magically transport me to some sort cosmic neverland! Little could I appreciate, that I was probably already there. In short, audio-nervousa was getting the better of me, and I lost site of the goal: enjoying recorded music. I decided to take a step back from this madness and start over...SLOWLY...MORE BUDGET MINDED...NO GIMMICKS. This time I would do a better job of managing, balancing, and accepting compromise. And above all else, I would just enjoy the music.

So for the last five years, my simple and basic system consisted of:

*Conrad Johnson Premier 11A 70W tube amp
*Conrad Johnson PV 10B tube preamp with phono stage
*Electrocompaniet EMC-1 CD Player
*Technics SL1210 MK2 turntable that I've kept as a spare from my DJ years in case I get a hankering for vinyl. I Sold my SOTA, due to lack of use.
*Harbeth 7ES2 speakers
*Kimber Kable PBJ interconnects
*Speltz Anti-Cable speaker wire

A Sam Tellig or Harry Pearson reference system, the above components do not make. However, this time that wasn't my goal...I just wanted to listen to music instead of worrying about $3,000 speaker cables being the weakest link. And to my surprise what glorious music these components produced!!! Oh how I was finally moved. Beautiful imagery and staging. The components just seemed to disappear leaving me with music. In my small listening room, everything sounded good. Silky smooth and so easy on the ears. Several friends who moved from two channel into the home theatre world were astonished at my latest "house sound". Maybe my mindset was different this time; older and wiser? Possibly I was more relaxed and less fussy? Or, maybe this time I didn't listen with my wallet?! Whatever the case, I found my own slice of Nirvana.

HOWEVER, there were occasions when the wife and kids left me alone to my vices, with the opportunity to really "crank the volume knob". Here I thought the Harbeths might like a little more power...more headroom. Not that the CJ was ever clipping...perhaps the tubes were just borrowing from Peter to pay Paul, when asked to work their magic at full tilt with these speakers?!?

Enter Jeff Rowland Design Group. I have ALWAYS had a thing for the JRDG gear!!!! From my perspective, Rowland is a hands-on mad man always pushing the envelope with newer technologies and unusual circuit designs. Doing it a bit different as it were - right, wrong, or indifferent - his way. Show the guts of a Rowland to an Electrical Engineer, and the head scratching begins! All this with a beautiful packing job to boot! Years ago, I auditioned the Rowland Model 2, 75 watt stereo amp with Synergy preamp at a local hi-fi store. I was blown away and had a hard time believing that some tubes weren't being slipped in, some place. I remember that audition being very lively and punchy without annoying. In short, I never forgot it.

Enter the Model 6 monoblocks. Once the decision had been made for more power, I had my amp choices narrowed down to the CJ Premier 12 (140 watt monoblock version of my Premier 11A) or something from JRDG. Deep down, I felt it was time to roll with one of the "better" solid state amps...go for a total change as it were. Remembering my audition with the 75 watt Model 2, the Model 6 with it's 150 watts seemed like just the dish for me. The units I bought from Jmcgrogan2 had the black face plates, which was an added bonus; I felt that the all black would be less "bling bling" than the signature Rowland silver, and less likely to influence anyone that happened to be over for a listening session. The black blends in much better, and is more subtle. However, once you inspect them up close, you quickly realize that you're looking at something special. Black aluminum tanks!

Enter Model 6 sound. For some reason I was expecting more harshness, maybe some grain. Even though I was previously impressed with the Model 2, I just couldn't let go of this notion that solid state was the devil's work and would annoy me with shrill sounds. OH HOW WRONG, I WAS!!! All of that tube-lover smoothness is there. The best imagery I've EVER heard....and this is something my CJ excels at! There are times when I close my eyes and feel like I'm not even listening to a "stereo"!! It's all there only with much greater authority! Much more concert like. More stage like. This sound is very energetic and moving...and that tube like warmness that I'm so fond of is still there with just a touch more detail. And the louder it gets, the better!!!! I'm amazed at how much bass my Harbeths can deliver - these are not large speakers!!! But now I have this punchy bass slam that's accurate and controlled. And here's the clincher: at louder volumes, the Rowlands can present this deep bass without losing any of the mid range or upper registers. No more borrowing...no sacrificing one area to furnish another. They just keep delivering and reproducing what you throw at them until some other component breaks down...in my case it's probably my small room or the monitors! I never thought solid state amplification could give me the same hair raising experiences as my beloved tubes. Time to quickly step off the audio merry-go-round, yet again, and enjoy what I have.

Thanks For Reading,
Jeff
sand_man
Many thanks! I'm thinking more and more that I should just pair thus up with a Rowland preamp and call it "done". Any reason I shoud avoid the Synergy II (non "i" version)? Is the IIi that much better? The reason I ask is that I see plenty of IIs on A-gon, well within my budget...one of them is even black.
Sand Man:

My only hesitation about a tube preamp is what I previously mentioned, which is to say, the inability of many of them to drive long runs of cable and impedance mismatches with amps (this is mostly a problem when they are paired with solid-state amps, which tend to have much lower input impedances than tube amps). The ARC LS-5 Mk. III has a fairly low output impedance for a tube preamp at 400 Ohms on average and the specs indicate it will work with an amp having a minimum input impedance of 20,000 Ohms. However, the impedance likely rises in the bass. The Model 6 provides a choice of 600 Ohms or 18,000 Ohms input impedance. Especially with long interconnects, there is a chance that you could experience some bass rolloff. This is not a reflection of a lack of quality -- some really high-end balanced tube preamps, like the Audio Research Reference 3 and BAT 52, are worse. Regarding the Audio Research Reference 3, John Atkinson wrote:

"The output impedance was also to spec., at 635 ohms balanced and 326 ohms unbalanced in the treble and midrange, but rose to 1437 ohms and 625 ohms, respectively, at 20Hz. This rise in source impedance rolled off low frequencies a little early into the punishing 600 ohm load (fig.1, bottom pair of traces), with a –3dB frequency of 17Hz. As this is a relatively low frequency and the preamplifier will never be used with a power amplifier having an input impedance as low as 600 ohms, this rise in source impedance will not be a factor in practical use."

In fact, Rowland amps have impedances typically seen on pro gear and you can in fact choose a 600 Ohms input impedance setting (which would work best with a Rowland preamp). The Rowland Synergy IIi, preamp, for example, has a balanced output impedance of 80 Ohms -- it will drive anything.

While you would likely be fine with the LS-5 on the Model 6's (set at 18,000 Ohms input, of course) and I would try it if I were you unless you have really long runs to your amps, the Synergy IIi is a risk-free choice.
Seriously thinking about the ARC LS5 MKIII that Raquel mentioned. I wonder what it is that makes this "one of ARC's best sounding"? The LS25 has also seems like a contender.

Still thinking about the VTL 5.5, too. Decisions...decisions!
Jeff, yes, a good preamp may well help you even farther down the road to nirvana than what you currently have. I also agree with Raquel, that running balanced works best with these amps. I haven't heard the top JRDG preamps as he suggests, and they may work quite well. I've always been more of a tube preamp fan myself, and think you can do better with tubes. Your CJ 10B may be a bit sluggish and warm, but there are many more extended tube preamps out there. You may want to try a BAT or ARC for example.

As for the battery supplies, I know many did like them, I however was not a fan. I heard these Model 6's with battery supplies, and the sound was smoother, and a tad warmer, but lost much of the extension and rhythmic drive that I felt drove these amps. As you know Jeff, I was using Stealth Dream power cords on these amps. IMS, IMHO, these amps sounded best with AC and with good quality cords.

As always, YMMV.

Cheers,
John
Sand-Man: If you have a budget, forget the Levinson 32 ($8k-$10k used). I think your best option is the Synergy IIi.

Enjoy.
Raquel,

Many thanks for taking the time to read over all of my audio jibberish, above! And for formulating your response so well!

Yes, after more sessions with the Model 6s, I can deffinitley tell there is something holding them back. I feel that this is good enough for now, but with just the right preamp, they will SING! No offense taken regaring my current CJ preamp...I know this is not a reference level component.

The Rowland Coherence II is a thing of beauty, and I've dreamed of it for as long as I have the Model 6s...though I've been a tube nut, I've always had a Rowland fetish (did I just say that out loud)! I'm afraid that even on the used market, it would be out of my range - know your limits! However, the Synergy could very well be a contender. I guess I'm afriad of not having tubes on the frontend.

I will also look into the ARC and Levinson models that you mentioned!

Best,
Jeff
Sand_Man:

I am glad you are enjoying the Model 6's. I ran those amps for three years and regret selling them. Some friendly advice:

(1) Try to buy the battery power supplies, as they were voiced with batteries and sound best that way (Model 6's come up for sale on A-Gon as often with batteries as without, and someone will be willing to sell the batteries separately). The amps produce objectively less power with the batteries, but subjectively sound like they have more headroom because you can turn them up quite a bit louder before the sound falls apart due to noise (higher volume also magnifies A/C line noise, and the difference with the batteries is not subtle). I suggest that you read Stereophile's multi-part review of the Model 2, which contains a section devoted to how the amps sound with the batteries.

(2) While they work fine when run single-ended, run them balanced, as they were voiced in balanced mode and sound best that way.

(3) Regarding what preamp to run with them, I don't know what your budget is, but I would look at a top differential balanced preamp. The safest bet would be a Rowland Coherence II Mk. 2 (disclaimer - this has been my main preamp for the last five years) and a Synergy IIi would also be very good. The Levinson 32 would also likely work well, although I am just guessing. All of these pre's are quite pricey, though. As for balanced tube preamps, I am against the common wisdom as to tube preamps generally and prefer top solid-state due to noise issues and the problems most tube pre's have driving longer interconnects, but if you must, I would try to find an Audio Research LS-5 Mk. III (some feel it is the best sounding preamp ARC has ever made), ideally turbo-charged with new capacitors and higher-shelf tubes. Ralph Karsten's (Atma-Sphere's) top preamp or the better BAT and Audio Research balanced tube pre's are also obvious contenders.

No offense intended, but your c-j PV10 is essentially a mid-fi component (I know it well) and is really holding you back.

Enjoy your Model 6's -- they are spectacular amps that layer sound like a top tube amp, yet are extended at the frequency extremes and have some of the highest resolution available from any amp technology. In solid-state, only the darTZeel is better to my ears.
Well Jeff, you do know what they say, "patience is a virtue". It's not always easy in this hobby, but it is true nonetheless.

Enjoy the music.

John
Thanks, John! One thing that I've decided to do this time around is take my time with the components that I buy. In the past, I think I was too hasty. There is so much amazing gear out there, and for some reason I felt the need to do it all!

This Rowland amp is amazing to me!!!! I never expected this. There is so much control. I know I've said this before about other equipment, but I don't see myself ever parting with these monos! And I'm in no way implying that my CJ did a bad job...it was a real stunner!!! Hell it kept me captivated for five years! It's just different. Maybe not even a fair comparison.
Hi Jeff,
I'm glad that you are enjoying the JRDG Model 6 monoblocks. I can't say that I am surprised, they were about the best SS amps that I've heard in my 30 years in the hobby. Yes, they (Rowland's) were surplanted by a tube amp, and I am happy. If I were ever to go back to *gasp* SS, the JRDG 2/6/8/9 series would certainly be top on my list.

Anyway, best wishes to you Jeff, and enjoy the Model 6's....

Cheers,
John