Purolator knocking on my front door is a regular occurrence – this is the method by which most components arrive at my house for review. But being greeted by a driver of a big 5 ton truck is rather rare, unless a 50-inch or larger TV is being delivered. Except this time, it wasn’t a TV – it was just a pair of loudspeakers. So why the need for such a big truck?
This time the shipment contained a pair of speakers from French manufacturer BC Acoustique. The engineers at BC Acoustique clearly took a size-is-no-object approach when designing the ACT Series A4 speaker, the company’s flagship speaker priced at $10,500 for a pair. By the way, ACT is short for Acoustic Coherent Technology. The A4 is a large floorstanding speaker, measuring 133.5 cm tall by 24 cm wide by 50 cm deep (or roughly 52.5 x 9.5 x 19.75 inches). It is one of the largest speakers to land for a review in my living room. Naturally a speaker of this size also has a substantial weight, 80 kilograms (or 176 lbs) to be exact. To put it into perspective, I dialed in at exactly 176 lbs last time I weighed myself. Unpacking and positioning these speakers were the last favourite parts of this exercise. Despite the A4s larger than average size, they actually look elegant and sophisticated.
Once the speakers were in place, I got my first chance to inspect them closely. The A4 features a four-way, bass reflex design. Its front baffle houses a BC100 horn tweeter sandwiched between two 18 cm polypro midrange drivers, while the side of the cabinet is home to a 30 cm paper bass woofer. The BC100 tweeter, common to all of the ACT series speakers, is the result of a collaboration between BC Acoustique and Fostex, a leading high-end driver manufacturer. The A4s are 4 Ohm speakers that have a frequency range rated from 25 Hz to 50,000 kHz with less then 0.2 percent harmonic distortion and a sensitivity rated at 94 dB (2.83V/1m). They can handle amplifier power up to 500 watts.
The back of the cabinet contains two pairs of WBT binding posts which allow for bi-wiring of the speaker. WBT jumpers are provided between the pairs of binding posts for those who will not be bi-wiring the speakers. There is also a large port hole in the rear of the cabinet. But this is all standard stuff. What I was surprised to find is the adjustable tweeter level panel which allows for the tweeter output to be adjusted from -3 dB to +3dB in 1.5 dB steps. The adjustment is done by repositioning a small metal jumper between pairs of holes. What does this adjustment do? Increasing the tweeter output should result in a slightly brighter sounding speaker, while reducing it should tame the high frequencies. If you want customization in a speaker – you’ve got it!
Finally, there’s the stuff that you can’t see. The A4 uses unique techniques to achieve the most inert cabinet, three resonators to absorb problematic frequencies as well as internal diffusers and non-parallel panels to break up standing waves.
My review pair of A4s came in a Wengé (very deep brown) finish but three other finishes are available: Maple, Cherry and Amarante. The gray, material speaker grilles attach magnetically to the front baffle, which eliminates the need for plastic anchors on the front baffle, giving the speakers a very clean appearance. The side woofers are covered by a matching gray material that stretches directly over the speaker.
I set up the A4 speakers in my reference system with a Classé Audio CP-500 preamplifier and CA-2100 amplifier. The speakers were bi-wired to the amplifier using GutWire cables. The sources were an ARCAM DiVA CD73 CD player and a Goldring GR1.2 turntable.
My initial listening tests were performed with the tweeter adjustment level in the zero position. During the first hour or so I experimented with the placement of the speakers looking for positioning that produced the best balance across all frequencies. The manual indicates that the side woofers should be facing in toward the centre of the system, unless you can allow substantial space between the speakers and the side walls in your room. I settled with the speakers being about seven feet apart and one foot away from the back and side walls, with a slight toe-in.
Once I sat down to do my critical listening, the first disc to hit the CD tray was Holst “The Planets” performed by the Los Angeles Philharmonic orchestra, conducted by Zubin Mehta. The very first quality of the A4s that I picked up on was the clarity of the high frequencies. The shimmering of the cymbals and ringing of the triangles were crystal-clear and their decay was perfectly natural.
The gentle “Neptune, the Mystic” track created a magical atmosphere in my listening room with a remarkable three-dimensionality, despite the speakers’ no-so-gentle size. The soundstage was vast in depth and width and the imaging was excellent. The amount of detail in this quiet track was remarkable – the A4s produced highly detailed high frequencies that were not at all fatiguing.
When listening to tracks like “La Femme D’Argent” and “Sexy Boy” from Air French Band’s “Moon Safari” CD, the A4s got a chance to extend deeper into the lower frequencies. The low frequencies were not only deep, as one should expect from speakers of this size, they were incredibly well articulated. The sound from the A4s enveloped my entire listening position, creating a giant, airy soundstage.
Moving on through my test material, I changed the pace with the Beatles “Love” disc. The lively presentation of this album prompted me to reach for my acoustic guitar and strum a few favourite Beatles tunes myself. The A4s had no issues keeping up with the pace and dynamics of this album. The midrange was natural and the bass was very musical. The balance between the mids and the bass was excellent.
Throughout my listening tests, I experimented with the tweeter output adjustment. I found that its effect was very gentle on the high frequencies. It took some going back and forth and I ended up settling for +3 dB position. I am not a fan of bright speakers and even in this position the high frequencies did not sound harsh or overbearing. The highs simply sounded fuller and very comfortable to my ears. The experience will vary based on your room and listening preferences.
Later the same afternoon I turned to a yet different pace of music, something more romantic: Respighi “The Birds; Brazilian Impressions” performed by the London Symphony Orchestra, conducted by Antal Dorati on a Living Presence Stereo record. And just when I thought that the sound couldn’t get any sweeter – it did! The A4s played with such natural dynamics and produced such a magnificent soundstage that I closed my eyes for minutes at a time and felt like I was sitting in front of a real orchestra. Perhaps the most noticeable improvements were the fullness and the extension of the low and high frequencies.
Did I find any sonic shortcomings of the A4s after endless hours of listening? I looked hard but just couldn’t find any! The only challenge with the A4s is that they are quite large and may look overwhelming in smaller rooms. But the good news is that this speaker’s smaller sibling, the A3, uses the same fantastic horn tweeter and much of the same technology as the A4 – plus it’ll save you a few bucks.
BC Acoustique has certainly hit the target with the ACT Series A4 speakers. These speakers had the ability to put excitement and emotion into every song that I played on them. The A4s have a terrific top to bottom balance and timbre accuracy. One of their highest points is the outstanding resolution of detail thanks to their well integrated horn-loaded tweeters. In addition to this, the bass has a natural, powerful extension. $10,500 is a small investment for a pair of speakers – but in this case it’s an investment that should provide you with years of listening enjoyment.
Distributed in Canada by Audio Dream Distributions
ACT Series A4 Speakers
Price: $10,500 CAD/pair