Jeff Rowland Design Group Concentra II Integrated Amplifiers

4.75/5 (4 Reviews)

Product Description

The Concentra II is a blend of control and power. The Concentra IIs power supply borrows design and technology from the Model 112 Stereo Amplifier, raising power output to 150 watts per channel to create more authoritative and effortless rhythm and timing while still maintaining the natural musical presentation.

Artistry, grace, and function remain the basic tenets of the exterior form. The timeless design of the Concentra II incorporates features to soothe the senses; the placid blue display, the gentle fluidity of the volume control, and the smooth curves of the non-resonant chassis combine to form an engaging whole that stimulates the visual and tactile senses as much as the aural; yet the sculpted exterior is still adept at performing the essential functions demanded of it by high performance: heat dissipation, resonance control, and isolation.

From the quiet opening notes of a jazz ballad through the power of a choral crescendo to the dynamics and punch of live blues, the Concentra II maintains the place established by its predecessor in the growing crowd of integrated amplifiers.

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Reviews 1 - 4 (4 Reviews Total)

User Reviews

Overall Rating:5
Value Rating:4
Submitted by stoni a Audio Enthusiast

Date Reviewed: January 22, 2006

Bottom Line:   
I bought this amp after reading other users experiences. Before this, I tried out Krell Kav 400, Pathos Logos, and some other int.amps to see if I could find a replacement for my good old Electrocompaniet ECI4. Not that I really needed it, the EC was a very good amp, involving, very natural sound, but with my B&W803 I missed the last peace off slam, dynamics, depth. Read the review underneath, I do agree with him, the 803s need a good amp to come alive.

The Krell gave me a lot off dynamics, but left me after a while with the impression that it had too much loudness and bass, it never ended, and it started to irritate me. When this first happened the Krell just had to leave the building. It lacked involvement, resolution. No, this was not good; it was a relief to go back to the EC again. Then I thought off trying a hybrid amp, like the Pathos Logos, valve preamp and solid-state amp. The disappointment was big, even my wife suggested that this was not the one! It sounded grainy, 2D, to say it straight; with no ear for music!

If you know the EC you may know that many people say it sounds like a valve amp. So, I started to think off Cary valve amps. After listened to some Cary int.amps, I was amazed, but at the same time I started to miss the dynamics that my EC had given me, and I didn’t want to start the endless search for the perfect tube, always have to think of turning off the amp to spare the tubes and so on…

I thought off giving up, until I started to read about the Concentra II. It seemed to combine the resolution off the tubes with the SS-dynamics and easy care. It was expensive, but I decided to give it a try.

From the first minute, I knew I had done the right thing! It sounded like the amp I had in my dreams. First it is crystal clear, with a resolution that goes beyond everything I’ve heard so far. But what I noticed most off all, was its involving sound; it gave the music a nerve and texture. The best way to explain it, it sounded natural, like the artists voice as if he had been standing in front off me, alive. The combination Concentra/803 was indeed perfect. The 803s tweeter can be pretty challenging for your ears if you have the wrong equipment. With the Concentra, they made a heavenly combination. They never sounded sharp, luckily, because I’m allergic to female voices with knifesharp ssss’! This was sometimes a problem with the EC and indeed it was with the Krell and Pathos.

The Concentra also sounds good with all my equipment; no matter if it is the TV, radio, CD-player, it always keeps it resolution, natural sound. The soundstage is wide, much wider than the EC, it also sounds more 3D, with a deeper soundstage. With my CD-player, a modified Electrocompaniet EMC1 UP, the sound fills the room, and the soundstage reaches far outside the loudspeakers placing.

Could it be any better? I’m a DIY-er, and opened the Concentra to see if there is anything I could optimize inside it, some obvious weakness. No, the parts were all of high standard, and so far I have left this topic. But what about the Power cord. I tried out some DIY-cords, Shunyata Tapian, along with some other cords. The Shunyata was the best, but this I needed for the CD-player, so I decided to get a Shunyata Python.

This was again a heavenly combination. The soundstage was even wider, deeper, and more natural. It also became more dynamic, the Concentra has dynamics, but not the same type as Krell and Pathos Logos. It is more polite, with the Shunyata, this was bettered a long way. I can only recommend all Concentra owners with the original cord, to try out some other well-branded cords. It really means a lot to the sound.

After this I stilled missed the last slam in the bass, and started to experience with the amps feet. I have good experience with Soundcare spikes, and I found out that replacing the two feet at the back, with one Soundcare spike was the best solution. It honesty does not make the big difference, but after this small tweak, there is no way back, the last slam needed was there!

I have to mention that I use a Mana-rack, Tara Labs The One IC and LC. By the way, if you have an EC EMC 1, try to place two and two Soundcarespikes towards each other under the player, it does magic…

The Concentra is among the best out there, in this class, it is more about what your preferences are. If you like an airy sound with a very high resolution, good midband and naturalness, pick the Concentra. If you want a turbo sound, with a never-ending speed and bass, pick the Krell, Pathos Logos or other similar amps.
I ‘ve ended my search for the ultimate amp, the next thing is to wait and pick up a couple of second handed B&W 803S...

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Used product for:   3 Months to 1 year

Duration Product Used:   Audio Enthusiast

Product model year:   2002

Price Paid:    $5900.00

Purchased At:   Private

Overall Rating:5
Value Rating:5
Submitted by ScofieldKjv a Audio Enthusiast

Date Reviewed: June 17, 2003

Bottom Line:   
Since going to the Concentra II, it has me thinking more on the importance of matching amp and speakers. I have been using B&W N803 speakers for the last year and though they are very well thought of, they never came to life for me, and I at times questioned my room. In fact, I was looking to replace the N803’s.

Enter the Concentra II; changing to this integrated has transformed my system, no exaggeration. It is obvious that the Concentra II is an awesome match with the N803, but it is my opinion that the Concentra II is simply a wonderful product. At some point I may get over to a friends house to try it on his Magnepan 1.6's to see how it performs on those.

The pairing of the C-II and the N803's is an excellent match is obvious as it doesn't matter whether I am playing my CD player (Electrocompaniet EMC-1UP), tuner (Yamaha T-2) or even the TV, the performance is vastly superior to any I have had in the past.

My past setups, Mark Levinson No.383 and VK-200 amp (w/BAT VK-30 pre), were rated at 100 watts vs. the C-II's 150 watts, the C-II is vastly more powerful in my system. In Larry Greenhill’s review of the No.383, he states, “Although I greatly enjoyed listening to the No.383, one thing was missing: more power…To its credit, the No.383 smoothly limited rather than clipping audibly…”, this is accurate; on the other hand, it seems the Concentra II never runs out of steam.

The music is all there in this setup, from top to bottom, I am not lacking in any area, this is very nice indeed. This system has an incredible midrange, is very detailed and bass that I haven’t heard in the past with the N803’s. (The N803’s are rated down to 42 Hz, so it isn’t earth shattering, but very nice nonetheless.) As one friend puts it, “it has that ‘continuousness’ that HP (of TAS) talks about.”

Build quality and aesthetics goes w/o question with Rowland, they are at the top, on par with the very best, rivaled by none. (The manual is lacking amongst the best, such as the wonderful manuals by Levinson.)

The remote is simple, I like it; volume is very quick. Input selection, mute, volume and balance can be adjusted via the remote.

I think it is obvious to see my enthusiasm with the purchase of the Concentra II.

My system:
Electrocompaniet EMC-1UP CD...
Acoustic Zen Silver Reference II (XLR) IC
Yamaha T-2 tuner...
Jeff Rowland Concentra II Integrated...
Audio Tekne speaker cables…
B&W Nautilus 803 speakers

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Used product for:   Less than 1 month

Duration Product Used:   Audio Enthusiast

Product model year:   2001

Purchased At:   Audigon-Used

Overall Rating:4
Value Rating:3
Submitted by big thinker a AudioPhile

Date Reviewed: May 15, 2003

Bottom Line:   
It may be a bit premature to write a review, since I haven't yet had a chance to use this amp with speakers that I think are in more or less the same league, but maybe others will be inspired to add their own comments in response. I traded up from the Concentra I, originally using Joseph Audio speakers, then Triangle Celius 202s, and now Linear Acoustics (i.e., Elac--German brand). I was never all that pleased with the original Concentra. Some described its sound as "warm," but for me it often tended to sound slightly bright or forward, and while it did well with efficient speakers and small ensemble music, it was not able to produce strong bass or dynamics as well as some other integrateds of even lower power ratings. The new Concentra II, with its higher power rating, may be better in this respect, while sharing the same basic sound in most other respects. The new Concentra may also have better layering, and while it doesn't necessarily produce more bass, the control seems good with the relatively efficient speakers I've been using. With the original Concentra, turning the volume to full with no source signal on let me hear only very a faint wash of pink transistor noise. With the new Concentra, however, the same test gives me a definite low-level buzz or hum. Perhaps this is responsible for what I sense as possibly an extra bit of hardness in the sound compared to the earlier Concentra, at least when pushing the volume up slightly. And one more gripe: Jeff Rowland's products are known for their looks, and previous users will have high expectations in that regard, but the faceplate of my new Concentra II is coarse-looking compared to my earlier one; quality control in this area might need to be tightened up, although new buyers won't know the difference (when I mentioned it in an e-mail to the manufacturer, I got a somewhat huffy reply in response).

All in all, it shows certain improvements over the earlier model, and seems to have greater capability in terms of power. Jeff Rowland Design Group seems to be far better known for its pre-amps than its power amps, though, and I am inclined to attribute the best qualities of this amp--its smooth and refined presentation--to the pre-amp. I'd suggest testing it with the speakers you plan to use to make sure it's capable of driving them. I'm not sure how highly to regard this amp yet, and intend to use it with even better speakers in the future. One columnist in Stereophile, however, did refer to it several issues ago as one of the world's best integrateds. Could be.

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Used product for:   3 Months to 1 year

Duration Product Used:   AudioPhile

Overall Rating:5
Value Rating:4
Submitted by Karl Snacth a Casual Listener

Date Reviewed: February 13, 2002

Bottom Line:   
Biult like a tomb easy to use.One inch from getting a ML383. Rowland sounds different but just as good if not better. I got a better price and saved 2500 BUCKS .Not to mention this unit is a work of art . Plenty of power driving a pair of B&W Nautlis 804 .The best I have heard. Tube sound with power and base without the bloom . If your in the market for the best a most definitely audition .

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Used product for:   Less than 1 month

Duration Product Used:   Casual Listener

Product model year:   2001

Price Paid:    $4600.00

Purchased At:   local dealer

Reviews 1 - 4 (4 Reviews Total)

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