Acoustic Research Wireless Speaker System
Maximum flexibility through modularity

Many dream of doing away with speaker wires when in-wall wiring is not an option. Today's easy-to-install wireless speaker systems can make this an affordable reality in small to medium home audio installations, whether that being a home theater or a multi-room audio installation.

It is true that wireless speaker systems come with problems of their own, in particular, they introduce latency delays which if not taken care of, would throw out of synch the sound from the different speaker channels in multi-speaker surround sound setups.

Equally important is power line induced hum, a common problem (but easily resolved) with systems driven directly by the speaker output on your AV receiver. Other issues compared with the less expensive wired solution include limited signal to noise ratio and interference from neighboring WI-FI networks, cordless phones, and even microwave ovens.

In other words, these are not the systems for the audiophile. But from our own personal experience we say that systems like the Rocketfish Wireless HD Audio System, Soundcast Wireless Audio, and the Acoustic Research wireless speaker solution reviewed here can do a great job in delivering quality sound. Mind you, wired is still king but if wired is not an option, you can still enjoy great CD-quality sound with today's wireless speaker systems.

Sure, most wireless speaker solutions are mainly designed to make the rear speakers in a 5.1 speaker setup cordless but there is still lot more room for wireless speakers in the home. It is here that the Acoustic Research wireless speaker adaptor comes in as it makes it possible to even ditch all the speaker wires in a 5.1 speaker setup. All it takes is simply adding more ARWR2 wireless power amplifier receiver units onto the main ARW20 Acoustic Research wireless speaker system.

It makes use of the same 2.4GHz 802.11 wireless computer network technology to deliver uncompressed full-bandwidth CD-audio quality in point to multi-point systems between the central transmitter to up to six different speaker amplifiers positioned anywhere in the room, or in that case, anywhere in the house within a 100ft range from the transmitter. This leads to a supported overall combined bandwidth of over 4MBits/second.

The Acoustic Research wireless speaker solution makes use of advanced algorithms to ensure interference-free audio. For the purpose, it uses an additional 7Mbits/sec bandwidth just for quality control. Unlike most 2.4GHz wireless audio solutions, the Acoustic Research wireless speaker system uses transceivers at both the transmitter and receiver end. This allows each receiver to have its own dedicated communications channel for delivering Quality-of-Service (QoS) information back to the transmitter, or to request retransmission of lost or corrupted packets, determine channel assignments and serve as a secondary method of measuring interference.

Each independent wireless receiver comes with its own amplifier, capable of driving 60W RMS into a 4-Ohm or 35W RMS into an 8-Ohm speaker load; definitely a modest output that should prove useful in a medium size home theater wireless speaker system equipped with a powered subwoofer.  Standard 5-way binding post outputs let you connect the receivers to practically any home theater speakers.

Like the Rocketfish system, transmitter and receivers are pre-linked at the factory but this modular Acoustic Research wireless speaker solution still enables the user to link any receiver—up to a maximum of six—to any selected audio channel on the transmitter through a simple yet unique linking process. This makes it possible to add additional receivers at a later stage to expand the system as required, or to use the system as the backbone behind a multi-zone wireless audio solution in the home.

Acoustic Research Wireless Speaker System - Main Components:

ARWT1 5.1 channel transmitter with 5 speaker-level spring-clip inputs and 1 line level RCA input designed mainly for subwoofer/LFE. However, the line level input on the AWRT1 can be used with any audio channel for a total of six full-bandwidth audio channels in that it still support full bandwidth audio.

ARWR2 Amplified Wireless Receiver module equipped with an efficient Class D amplifier capable of delivering over 60W RMS into a 4 ohm speaker load. Standard 5-way binding post outputs let you connect the receivers to practically any home theater speakers.

ARWS3 Line Level Subwoofer/LFE Wireless Receiver module with an RCA output for driving powered subwoofers. The AR subwoofer unit is band limited to match the subwoofer response but it is possible to use an ARW2 module instead of the ARWS3 to drive say a small non-powered subwoofer or a standard speaker.

All modules within the Acoustic Research wireless speaker solution come with DC inputs driven through the provided AC-DC adaptors - 12 volts DC for the transmitter and the ARWS3 modules, and 26V DC for the amplifier units.

The ARW20 Acoustic Research Wireless Speaker Kit comes complete with one ARWT1 transmitter module and two ARWR2 wireless amplifier units. As stated earlier on, four additional ARWR2 wireless amplifier receiver modules may be added as need to the remaining unused channels on the AR transmitter. In addition, up to six ARWR2 units may be linked to any audio channel on the transmitter unit. This makes the ARW20 the basic building block for a complete wireless speaker solution.

Instead, the ARW51 wireless speaker kit includes five ARWR2 and one ARWS3 modules apart from the transmitter unit, making it the ideal solution to do away with all your speaker wires in a 5.1 surround sound system installation.

Acoustic Research Wireless Speaker Performance

The system under review was the ARW20 coupled with ARWR2. The scope was to test the use of the Acoustic Research wireless speaker solution in a 7.1 environment with the rear and back surround speakers connected via the AR wireless speaker modules.

Installing the system was a snap; simply connected the AR units in the audio loop and powered up. Linking the additional ARWR2 units to the transmitter unit also turned out to be a simple straightforward process. Once set, it just behaves as any other wired speaker system.

Interference and Range: Like the Rocketfish solution, the user manual indicates a maximum range of 100 feet. That leaves quite a few options open for the Acoustic Research wireless speaker system when used as part of a multi-room audio installation. We did not have the possibility to test the system at its maximum range but at up to 85 feet away, sound quality was as if the sender and the receiver units were in the same room.

As stated earlier on, the system uses 2.4 GHz wireless technology to transmit the audio signals. We have a WLAN using 802.11 N+ wireless gear; the sender unit was just 15 feet away from the main router, and there are some four or five neighboring Wi-Fi networks in the area.

The Acoustic Research wireless speaker system did still manage to produce clean audio with no problems of signal dropouts but our WLAN did slow down considerably - at times even going down completely - especially once all four wireless audio channels were activated.

But this is basically the same as with other 2.4GHz wireless audio systems even though the Rocketfish we reviewed way back in 2007 - possibly due to a less congested network space at the time of the review - did not cause such problems. These systems are often characterized by a relatively strong wireless signal to ensure interference-free audio; but as a result, Wi-Fi networks in the area would generally suffer.

Audio Quality: The overall performance of the wireless audio link is very good. We still say 'wired is king' but as stated earlier on in this review article, with the Acoustic Research wireless speaker kit, it is really hard to perceive any difference in audio quality between a wired and a wireless setup with most audio content.

The power amplifier in the receiver unit is a Class D amplifier - meaning that while these are the best in terms of power efficiency (with efficiencies in excess of 90%), in terms of sound quality, these amplifiers are often at the lower end of the sound quality scale - with higher noise and distortion levels. The Acoustic Research wireless speaker amplifier supports 1% THD at its rated output - while signal to noise ratio stands at 70dB; these ratings are typical of most HTiB systems.

System Latency Delay: As with all wireless speakers, the Acoustic Research wireless speaker system introduces what is referred to as latency delay (unwanted time delay) over the wireless audio link; latency delay stand at 14msec—one of the lowest around for such systems.

Still, this latency delay has to be taken into consideration in a hybrid wired/wireless multi-channel audio setup, such as when connecting the surround rear and back channels over a wireless link while wiring the fronts straight to the AV receiver. The introduced latency delay has to be deducted from the delay settings for the surrounds applied through your AV receiver to ensure that all audio channels stay in synch.

This delay issue is irrelevant when the AR wireless speaker system is used to route stereo sound to a secondary room in the house, or when all speakers in a 5.1 surround sound setup are connected over wireless links.

Hum Issues: One issue some may experience is the presence of hum on speakers connected to the Acoustic Research wireless speaker amplifier units when switching off the AV receiver, as well as when the audio signal is low. The extent of how much hum you experience depends on the mismatch between your AV receiver output and the Acoustic Research wireless speaker transmitter input. This is typical of wireless speaker systems using the speaker output as their input; in other words, it is not something related to the AR system only.

As further expressed in our wireless speakers installation tips, for some audio systems, presenting an open circuit on the speaker outputs would throw the system into all sorts of problems. The impedance as seen by an AV receiver on its speaker outputs connected to a wireless speaker transmitter unit is typically a few 1000 Ohms - almost an open circuit for an amplifier designed to drive a 4 to 8 ohm speaker load.

Loading the rear speaker outputs on the AV with a 100-ohm resistor would generally work fine. The value of this dummy load resistor is not critical. Just try not to go much above the 100-ohm - preferable lower but then take care about the power rating of the resistor since lowering the resistor would require a higher rating. The 100-ohm seems the ideal balance but experimenting here is critical.

The resistor power rating should be based on the receiver output. A receiver designed to deliver 25W into 4-ohm speakers require a 1 Watt rating; if the same receiver delivers 25W into 8-ohm speakers, than use a 2W resistor. If your AV receiver delivers 50W per rear speaker, then double the resistor rating in either case. Take care that as you increase the resistor rating, it starts to get really hot - so check this out after the first few minutes of use.