What a delightful all vacuum tube amplifier and what a super bargain we have here. Monoblocks for $4000 the pair …this is audio heaven for the not so deep pocketed audiophile enthusiast. They'll drive speakers as inefficient as 87dB to enormous levels and sound sweet and winning. Do some tube rolling, experiment with interconnects, and you'll get mighty close to audio heaven. The Opera's sing and look great with excellent industrial design. This is the kind of fun product that will bring real joy for the holidays to your eyes and ears!

The Opera's are well made and look solid. They are filled with premium parts, many hand soldered, and exclusive caps. Very good Electro Harmonix tubes are included and the circuit has lots of headroom. EH 6CA7s sound quite warm and delicious and you won't be disappointed for a minute. No biasing seems to be needed as long as the output tubes are similar. I love the on/off switch on top of the unit for easy reach. 4/8 ohm flexibility plus solid connectors makes these useful over the long haul. Comes with single-ended inputs. I put them on my Zoethicus stands and used all the same cables as my amp references except subbing Harmonic Technology's new and fast sounding ProSilway 3+ between the preamp and amps. Other than the Opera amps, no other changes to the system were made.

This is a great cable/amp match. Talk about high value and solid neutrality, the Operas were excellent here. Disk after disk yielded agile, warm, and musical sound. They were tighter than I expected from EH 6CA7s and were certainly sophisticated for their modest $4000 cost. The Harmonic Tech cables are sonic over-achievers and the delicious sounding Operas are a perfect compliment. You'd expect this kind of power and drive from 150-watters not just 75-watters! This is a sure fire recommendation.

I could have lived forever and a day with this combo, but I wanted even more definition!

I then pulled the high value HT cables at $475 per meter and subbed the state of the art Kubala-Sosna Emotion Interconnects at $2700 per meter.

This is where it gets really interesting. On first listen and totally stock, the Operas were certainly more elegant and rich with the Kubala-Sosna. I just prefer less high caloric sound with my tubes. I wanted a faster, tighter sound with more speed and snap, tighter bass and enhanced sparkle on top. As delivered and with the Kubala-Sosnas, the Opera's are B+ for sound and A for build. I tweaked them to A- for sound with a few inexpensive changes. This makes the Opera's perform in the $6000-7000 range with a $4000 price. Very nice!

Pull the EH 6922s and replace them with Tungstram PCC88s at about $45 each and replace the Phillips 5687 with a Tung-sol 5687 at about $40. Just three little tubes per unit to live the dream! They are available at Upscale Audio and VTV. No other changes needed. By the way, turn the amps off for this tube change! The EH 6CA7s are quite good and about as musical as current production allows.

With these changes, holy cow the Opera's are wonderful! Gone is the vast majority of slowness and any vintage tube sound. I won't estimate how close they come to my reference amps at $13,600 the pair, but you won't be sorry you bought the Operas. They have tons of texture and loads of snap and power. Hard to believe what a few small signal tubes can accomplish, but the design of this class AB amp is on target and should perform very well.

From the Consonance website:

Theory of Operation

The amplifier is a push-pull Class AB mono power amplifier with two pairs shunt-wounded EL34 output power tubes per channel. It uses little global feedback. Signal goes first to the 6922 dual triode acted as input stage, then to the 6922 dual triodes acted as double drive stage. The 5687 drive the EL34 output tubes which are transformer-coupled to the load (In this case, the speaker.).

Specification:

• Power: 78 watt x 2, RMS 1kHz ( Ultra-linear )
• Total Harmonic Distortion: less than 1%( 50watt, 1kHz )
• Frequency Response: ( -3dB points at 50 watt ) 6Hz-100kHz
• Input Sensitivity: 700mV
• Input Impedance: 100k ohms
• Output Impedance: 4, 8 ohms. ( User selectable )
• Signal/Noise: 90dB
• Consumption: 90watt x 2
• Overall Negative Feedback: Little
• Tubes: EL34/6CA7 x 8, 5687x 2, 6922 x4

Highs

You'll love the elegant airy highs usually only available from tube amps. Lots of definition and charm here. Loads of detail and harmonious textures will compliment fast tweeters and the like. Never, ever do the Opera's get strident or harsh with the Kubala-Sosna cables. You want fine tube sound and they deliver. Somewhat less detailed than the very best, but hey, still a super deal.

Mids

Lots of midrange energy for all kinds of music…you'll enjoy classical or jazz with the Operas. Vocals are lush, textured, and focused. Instrumental colors are spot on. Definition is very, very good. This is involving sound, one you will listen to for many hours. Lot's of depth and breadth to the soundstage. My goodness the Kubala-Sosna cables and the Operas are one wondrously musical combo. I would like even more snap and speed, but the Opera's are very good and mellifluous. If the amps err, it's more than forgivable at this price. Hey, I like the sound a lot as you can tell. If solid state could sound like this, you'd consider it a breakthrough!

Bass

This is good to very good sound. It's quick and textured and more than satisfactory. I am used to more slam and definition down under, but EL 34s are typically slower and more bloomy on the bottom. If you want top bass performance from tubes, you'll spend much, much more. You may want to look elsewhere if your speakers have a significant bass hump in their design or try leaner sounding interconnects or speaker cables. The Opera's rarely ran out of gas, however. Clipping is rare. Their dual mono design is the way to go for best bass performance on demanding music in my experience. They have very powerful sound overall and textural cues with the K-Ss are lovely.

The Operas are worth the time to cable match and tube roll. You must experiment with cable combinations and you'll get just the right textures and speed for your setup. At this price, you can afford to buy better ancillaries to bring out your personal tastes in system performance. The Opera's flaws are few and easily overlooked.

In conclusion

The Consonance Opera's are a terrific deal and look and sound much like the expensive audio jewelry you see at the best salons. Audiophiles should work for top sound and a bit of tube rolling and cable matching brings out the best from the Opera's. Wonderful metal work and facilities compliment exceptional sound from such a modestly priced pair of monoblocks. The mids and highs are elegant and detailed with the kind of sound you can take home to mother. The bass is good enough to satisfy and entertain unless you have only had a diet of solid-state sound your entire life. More powerful sounding than you would expect from 75-watts per channel indicating excellent design and R&D. I liked the Opera's and enjoyed many hours of beautiful, sweet music with them. I predict that you will, too. Robert H. Levi

A few words from Dave Clark

Uh... yeah! These are truly stellar and at a hair under $4k ... well they are a real steal. I am in the process of writing a formal take on these, but again let me say that while they do have shortcomings (heck they are $4k!!) when compared to my $10k 200-watt Class A Claytons, what they lack is rather moot. They play music and sound very, very, very good.

Cyber 800 amplifiers
Retail: $3990

Opera Audio
web address: www.opera-consonance.com

Norvinz
web address: www.norvinz.com

North American distributor/representative for Opera Audio/Consonance:

Ultraviolet Audio
web address: www.ultravioletaudio.com

(All amplifiers, including the Cyber 800 now feature a fully transferable, 5 year warranty.)