The power amplifier we bring to these pages is designed by Electro-Voice and is part of the PRECISION SERIES. In the manufacturer's own words, "Congratulations! You have just purchased an Electro-Voice power amplifier that uses the most advanced technology." Is it true? Many user manuals tend to start like this, although some of them must be right. The PRECISION SERIES (or P Series) of power amplifiers combines excellent audio performance, reliability and operational stability. Each amplifier (including, at the very least, the P900 RL model as well) features the RCM-24 remote control module, which allows everything from monitoring the amplifier's values (output current, load impedance…) to controlling and configuring it.
Under control
One of the strong points of this amplifier is precisely this remote control system. It provides an overview of the amplifier's functions and performance at any time. An ambitious installation could control, manage and configure up to 250 amplifiers from the same series and, using the Windows program IRIS (Intelligent Remote & Integrated Supervision), control and monitor the entire PA from one or several personal computers. All operating states (such as amplifier power-on, temperature, modulation, limiting, activation of protection systems, load impedance deviation, etc.) can be displayed and stored, making it possible to anticipate any malfunction or, if disaster strikes, study the data stored on disk to find the source of the problem and fix it.
Because it allows monitoring of output current and voltage, it's also possible to get real-time information on the state of the loudspeakers. Every time the signal exceeds the preset limits, a warning is triggered and the values are saved. Combining these measurement values provides information, for example, on the real impedance of the cabinet and the connected cable across the whole frequency range, displaying the result graphically on the computer screen; by comparing this value with a reference, we can recognize any defect or irregularity in the loudspeaker.
But this system offers other no less interesting features. The RCM-24 module also includes signal processing functions. In total there are 20 parametric filters (crossover filters, delays, routers and level control, as well as compressors and limiters per channel). All parameters can be freely edited and stored in any of its eight user memories. This processing is independent of the network control system, so the configuration is retained even in the event of a network failure.
This processing takes place in the digital domain, so it includes 24-bit D/A and A/D converters and 128x linear-phase oversampling (the resulting internal word length is 48 bits). The result is outstanding, as is its 115 dB dynamic range.
More everyday use
Let's tackle the part of this amplifier that interests us most. It is a standard-width module for 19" rack mounting, 132.5 mm high and weighing a not-insignificant 17 kg. Its weight is undoubtedly considerable, but given its clear orientation toward fixed installation, it needn't be a problem (it would be another matter if we wanted to haul it gig after gig, with those 17 kg being a "hard" burden on our backs). The front panel is absolutely simple, with no controls at all except the power switch. Three indicators per channel (obviously it is a stereo amplifier) tell us that the amplifier is working properly, whether signal is arriving (or not), and show the ever-tedious red limiting LED. Another three indicate the activation of any of its effective protection systems, power-on and "standby." This last LED is uncommon in this type of product, but given the remote control possibilities it is useful, as it confirms that the unit is connected to the mains (via a typical IEC socket) and powered on, while indicating that it is "off" and waiting to receive commands via the network. The rest consists of ventilation grilles and two carrying handles flanking the unit (obviously, given its weight, of sturdy construction).
The rear panel is divided into three clearly differentiated sections. On one side, the signal input via XLR connection and the whole network control system (including network input and output via RJ45, BUS selectors, RS-232 interface and line output and input connections, which include, for example, the processed signal output as a preamp out for any use we may fancy). Next comes the aforementioned IEC socket (with its corresponding easily replaceable fuse, without needing to open the chassis), a ground lift switch and, finally, the power outputs, which in our case are binding posts, meaning bare wire must be used. Electro-Voice has placed this connection, which I personally consider dangerous (a strand of the copper wire can accidentally touch the opposite conductor and cause a short circuit), on a removable metal plate, making it easy for the owner to replace the connection system with a much more reliable one (something I always recommend doing).
Its insides
After removing 15 screws, you can see inside. Your eyes go straight to the generous toroidal transformer placed in the center right. The electronic circuits are arranged on different boards, with all the power stages isolated in a small Faraday cage with forced ventilation. The fan only kicks in when the temperature reaches a certain value, so the first time you switch on this amplifier, silence reigns. The placement of the various electronic boards ensures minimal interference between them, as also shown by the isolation of the small transformer which, I assume, powers the digital section.
The ample free space around the transformer and its generous ventilation grilles likewise ensure more than adequate cooling of the amplifier when it reaches its limits. Although I doubt it can be seen in the images accompanying this article, my "theory" about the output connection plate is confirmed, as is the generous space at the rear that allows any combination to be used.
In use
I wasn't able to test any of the connectivity or DSP features this amplifier boasts, but I could test what really matters: how does it amplify?
For the tests I used a MIDAS Venice console feeding the amplifier directly via XLR. As loudspeakers, I started with a pair of high-performance two-way JC N Series cabinets, although later I switched to JBL MPRO monitors. In both cases they are 4-ohm loads, which, according to the manufacturer, means up to 600 W per channel (500 W according to IHF-A). One way to check the performance of an amplifier (and of any other component) is by comparison, so I set up one of my familiar Crown CE2000s, adjusting the output levels so that both cabinets with their respective amplifiers delivered the same output level (using an SPL meter can be unreliable because of ambient noise). You can find my opinions on the CE2000 in ISP issue 56, pages 60 to 64.
Apart from the difference in power, I can say that our guest has very good current delivery, although it lacks a bit of aggressiveness and is a little less fast than the aforementioned CE2000 (although they are slightly different types of amplification). But even though some may think the lack of aggressiveness and speed is a bad mark, it can also be just the opposite. In fact, an installation meant for more or less quiet music, based on vocals, acoustic instruments, etc., will find an excellent ally in this P1200RL. But there's more.
Using the same cabinets, reliable cabling, console and source, the Electro-Voice shows a slight lack of low end and a tremendously controlled midrange, with very well-balanced highs. Although a certain dynamic compression can be noticed, the response is tonally balanced, reinforcing the previous opinion on the most recommended use for this amplifier. But let's not be radical and rule it out, for example, for use in an active system powering subwoofers. It will obviously perform perfectly, thanks to its excellent current delivery capacity. Just those somewhat lazy (but at the same time smooth) transients and that magnificent ability to deliver a convincing sound, especially in the mid and high audio spectrum.
In "normal" applications, you miss having volume pots on the front panel. It's true that we can do this remotely from a PC or with the help of a preamp, but often, especially live, these controls are almost essential. In fact, this reinforces its "fixed installation" outlook.
Conclusion
I take the network connection, control, remote management and DSP system on faith, but I must mention it as a more than interesting feature for fixed installations. Good results in current delivery, with a very attractive price-per-watt ratio. Electro-Voice has spared nothing in this respect, considering this model suited to fixed installation and forgetting for a moment about the need to drastically reduce its weight. Worth trying.
