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Equipment Review
November 2006

Energy Reference Connoisseur RC-70 Loudspeakers

by Philip Beaudette

 

"Something special."

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Review Summary
Sound "The RC-70s are lively when the music calls for it, but not fatiguing or bright. There is an enthusiasm to their sound I found involving, a sort of get-up-and go that demands attention." "On orchestral works the RC-70s exhibited a wide soundstage with convincing depth and good image placement."
Features "The three-way bass-reflex rear-vented design features a complement of four drivers. This includes a 1" aluminum-dome tweeter, a 5 1/2" Kevlar midrange, and two 6 1/2" Kevlar bass drivers. Crossover points are 600Hz and 2.4kHz." "All models in the Reference Connoisseur line are available in a choice of three real-wood veneers: cherry, rosenut and black ash."
Use "The RC-70s come supplied with port plugs to help attenuate the bass in smaller rooms…. Adding them improved detail in the mids and highs and eliminated congestion in the low frequencies that is an inevitable outcome of using a large speaker in a smallish room."
Value "At their price, I have never heard a speaker I like more, including my own PSB Platinum M2s."

"The point of diminishing returns" has become part of the audiophile lexicon to define the price for a given piece of equipment above which spending more money yields only small improvements in sound. With audio as with many things, there isn't always a direct correlation between cost and performance. Reviewers sometimes encounter products that achieve 95% of the performance of their state-of-the-art counterparts but cost a fraction of the price.

In the case of speakers, I've heard various estimates for where the point of diminishing returns lies. For a floorstanding speaker, some say that $10,000 USD will get you "most of the way there," while others place that figure closer to $5000. Sometimes, however, a speaker such as the $2000-per-pair Energy RC-70 comes along and requires us to ask whether even $5000 is a little too high. Does the RC-70 sit at that point on the price-performance curve where spending more money buys only small improvements? Read on for details.

Description

Energy is a well-known brand in the Canadian loudspeaker industry. That's not really a surprise given that they've been designing and manufacturing speakers for over 30 years. In fact, Energy's founders were some of the original members of the National Research Council who studied psychoacoustics and correlated measured speaker performance to people's listening preferences. From this research Energy followed three principles that have provided the backbone for the brand's design philosophy: flat on-axis frequency response, wide and constant dispersion, and low distortion and resonance. These sonic objectives bear a strong resemblance to those of Revel and PSB, not surprising when one considers that all of these companies have their roots at the NRC.

The RC-70 is the largest speaker in the Reference Connoisseur line that was introduced in 2005. Measuring 39 7/8"H by 7 3/4"W by 15"D, each speaker weighs 60 pounds. The three-way bass-reflex rear-vented design features a complement of four drivers. This includes a 1" aluminum-dome tweeter, 5 1/2" Kevlar midrange, and two 6 1/2" Kevlar bass drivers. Crossover points are 600Hz and 2.4kHz. Energy rates frequency response from 31Hz-23kHz (+/-3dB). Anechoic sensitivity is given as 92dB (approximately 95dB in a typical room), and nominal impedance is 8 ohms. Such high sensitivity and impedance mean that a modest amplifier should easily drive the RC-70s. I imagine 50-100 watts would be sufficient for most listening, but Energy says the RC-70s can handle up to 250Wpc.

With their Reference Connoisseur series, Energy has introduced several technologies aimed at raising the performance bar in some key areas. For example the high-frequency driver is what Energy refers to as a "chambered Hyperbolic aluminum-dome tweeter" in which the driver is enclosed within its own chamber. Energy claims that by acoustically separating the high-frequency driver from the midrange and woofers its crossover frequency can be set lower, thereby improving dispersion and power handling.

The midrange and woofers are unique in that they do not use a typical "half-roll" surround design, but rather a ribbed elliptical one. According to Energy, the use of an ellipse eliminates surround distortion, increases driver excursion, and provides greater piston area for improved efficiency. Furthermore, the midrange and woofers feature a proprietary weave and thickness that are treated with an aqueous coating for improved rigidity to move resonances out of the audible frequency range. The use of what Energy calls "a tapered crossover" enables the top woofer to perform double duty as both a midrange and woofer, while the bottom woofer handles bass exclusively. Energy states that separating frequencies in this manner provides the smoothest transition between drivers, producing a more seamless, integrated sound. Finally, each speaker is constructed from MDF and features Energy's patented Interloc bracing system. This makes the cabinet more rigid without reducing internal volume.

All models in the Reference Connoisseur line are available in a choice of three real-wood veneers: cherry, rosenut and black ash. The review pair of speakers was supplied in rosenut. Featuring a high-gloss black plinth, their appearance was simply stunning. Fit and finish were flawless. Black cloth grilles attach to the front baffle via magnets and give the speakers a very elegant, unimposing look. Removing the grilles shows off the silver drivers and offers something more high-tech. I kept the grilles in place because I preferred this appearance in my room. Two sets of heavy-duty gold-plated binding posts are provided for biwiring duty. These formed a nice, snug fit with the banana plugs I used.

Sound aside, Energy has set a new standard at the RC-70's price for what consumers can expect in terms of build quality and appearance. Not many speakers I've seen provide this level of craftsmanship and attention to detail for $2000. The use of real-wood veneer as opposed to vinyl is an especially nice touch that I think sets the RC-70 apart from many of its peers. Furthermore, the choice of three finishes means one should easily find something that will fit well with room décor.

Setting up

I set up the RC-70s in my 16'L by 12'W by 7 1/2'H listening room by moving them as far from the walls as I could to produce the largest soundstage. In my room, this meant leaving 30" between the speakers and the front wall, 36" from side walls, and placing the speakers 56" apart. They were connected to my usual electronics -- NAD C372 integrated amplifier and NAD C542 CD player -- with AudioQuest Type 4 speaker cables. I also used a Simaudio i5.3 integrated at various points. AudioQuest Copperhead interconnects finished things off.

The RC-70s come supplied with port plugs to help attenuate the bass in smaller rooms. I started my audition without them, but I inserted them later and heard significant improvement in the sound. These speakers are intended for larger listening environments than mine, so without the port plugs the bass was overblown. Adding them improved detail in the mids and highs and eliminated congestion in the low frequencies that is an inevitable outcome of using a large speaker in a smallish room.

Energy recommends 100 hours of break-in before the speakers are at their best. I didn't need 100 hours to get them to open up, but I would say that a good 10-20 hours were necessary to breathe some life into them. After that time I couldn't stop playing music.

A new reference?

The first moment it occurred to me the RC-70s were something special came when I wasn't doing any critical listening. I was reading in my listening room as they played quietly in the background. I remember the disc and song well: Ben Harper's Free Your Mind [EMI Virgin Music B000000W9M] and "Ground on Down." Even at low volume, percussion had plenty of impact, and the musical picture was vibrant and full of energy. The RC-70s are lively when the music calls for it, but not fatiguing or bright. There is an enthusiasm to their sound I found involving, a sort of get up and go that demands attention. The RC-70s aren't inherently forward-sounding; rather, they take on the sound of the recording and the upstream equipment. Without planning to, I listened to the whole disc.

A recent musical interest of mine has been the Seattle band Alice in Chains. In 1992, AIC released Dirt and were vaulted to superstardom in Seattle's music scene, culminating in their headlining the Lollapalooza festival in 1993. Unfortunately their lead singer, Layne Staley, was addicted to heroin, and despite several future releases, AIC never toured again. However, in 1996 Staley emerged to record an Unplugged session for MTV. AIC Unplugged [Sony Music B000002BM5] is a superb album, and really showcases the band's musicianship. "No Excuses" features tight, punchy drums and the sort of openness that makes it easy to imagine the group across the front of the room. Listening to the RC-70s, I again found myself listening to the whole disc.

On "No Excuses" the drums were a bit more prominent and the sound was a little warm through my NAD C372. When I switched to the Simaudio Moon i5.3 integrated amplifier there was even greater clarity in the highs and the whole presentation became more focused. Essentially the noise floor dropped and detail emerged from the shadows. This demonstrated that with a more detailed amplifier the RC-70s are able to sound equally detailed. I wished I still had the Bryston B100 SST on hand to pair it with the Energy speakers. I imagine the transparency and power would have been downright addicting, However the NAD/Energy combination worked very well together and made listening a memorable experience.

On orchestral works the RC-70s exhibited a wide soundstage with convincing depth and good image placement. On Mozart: arie & duetti [CBC Records SMCD5239] the violins in the overture to Die Zauberflöte pan across the stage, beginning slightly out front of the right speaker then down across the back before finishing slightly up front of the left speaker. As the sound moves in front of the listener there is great coherency among the players, making it easy to picture their locations on the stage. Additionally, the RC-70s handled dynamic peaks with ease. During the same Mozart overture, brass, strings and percussion give rise to bursts of sound that never caused the speakers to show any stress or compression. The sound was big and bold. The music was beautiful -- a fine performance to celebrate the 250th anniversary of Mozart's birth. The RC-70s did right by the celebration, and they raised a question in my mind: "How much more money would I need to spend to find a speaker I prefer substantially more?" I suspect it would be far more than Mozart was paid for his composition, adjusted for inflation, of course. The RC-70s are that kind of good.

Comparisons

I said it earlier, but it deserves repeating: The Energy RC-70s are special speakers. They perform well with all types of music, and they never really add themselves to the sound. Good recordings sound good, bad ones sound bad -- like it or not.

Because I thought the RC-70s performed to such a high standard, I decided to compare them to my own PSB Platinum M2s ($2500/pair), a minimonitor with some guts. I went back to the same Mozart overture in Die Zauberflöte and noted a bigger -- though not as crystal clear -- sound through the Energy speakers. Their low frequencies were far more extended than those of the PSBs, and this had the effect of adding space to the recital hall where the recording was made. Obviously the RC-70s should have more bass because the PSBs are minimonitors, but this is still worth noting if you are in the market for speakers and need (or don't need) deep bass.

If I had never heard the PSB Platinum M2 tweeter, I'd say that the RC-70 produced the best high-frequency performance I'd ever heard. It never errs on the bright side (unless the music is inherently bright) and it exhibits excellent detail. Still, when I switched over to the M2s, I found the tweeter even smoother, with more detail and what I can only describe as a very tidy sound. The M2s sound very clean, and reproduce vocals better than any speaker I've heard. While the RC-70s create well-focused images, with the M2s these images are razor sharp and give a better sense of space around each instrument.

But -- and it's a big "but" -- the M2s cost $2500, 25% more than the RC-70s, and they're minimonitors! At that price, I would expect outstanding performance from them. The fact that I thought the RC-70s deserved comparison with one of PSB's flagship Platinum-series speakers should say something about how highly I regarded the RC-70s' performance.

Conclusion

In my introduction I asked whether the RC-70 might set a new sonic standard at their price. More specifically, I wondered if $2000 really is the point of diminishing returns for a pair of floorstanding speakers. Although the RC-70s are wonderful, I still think that this honor is reserved for speakers that cost closer to $5000, where the competition is especially fierce. Many companies offer models around this figure, and I've heard some I liked more than the RC-70s. However, that the RC-70s get very close to the quality of these considerably more expensive designs is an important point. Their sound is extremely satisfying in so many regards, and they are such highly resolving and refined transducers that I can imagine many music lovers (myself included) living happily with them for a very long time.

My advice to potential buyers of the RC-70s would be to spend money on quality electronics to extract everything they have to offer. They can sound very good with budget gear, but their performance was elevated as the quality of the upstream components improved. The RC-70s are certainly revealing. When fed a signal that is as refined as they are, the result is so impressive that one might forget all about upgrading and simply get on with just listening to music. If this isn't the point of being an audiophile, I don't know what is.

...Philip Beaudette
philipb@soundstage.com

Energy Reference Connoisseur RC-70 Loudspeakers
Price:
$2000 USD per pair.
Warranty:
Five years parts and labor.

Energy Speaker Systems
3641 McNicoll Avenue
Toronto, ON M1X 1G5 Canada
Phone: (416) 321-1800
Fax: (416) 321-1500

Website: www.energy-speakers.com

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