Hands-On Review:XTi 4002 Power Amp
Power to the people—lots of power
By Russ Kent
Harmony Central Contributor
Crown's XTi Series power amps broke the mold by providing more power and features in smaller, lighter, and more convenient and elegantly designed cases. The modelreviewed here offers the second-highest output (in terms of wattage) in the family. It's the only amplifier on the market in this price range that has fully integrated digital signal-processing tools, or DSP.
The, like its XTi siblings 1002 and 2002, is a two-rackspace unit that's 12-1/4" deep and weighs 18-1/2 pounds. Used with the default left-right outputs, it sends 650, 1,200, or 1,600 watts into 8-ohm, 4-ohm, or 2-ohm loads, respectively. All XTi amps can be wired in bridge-mono mode for 4- and 8-ohm loads, supplying a range of power from 1,000 watts into 8 ohms (XTi 1002) to a whopping 6,000 watts into 4 ohms (XTi 6002). You will not lack for power with an XTi in your rack!
The front panel of the 4002 has LED meters and rotary pots for output control of each channel. The meters are marked with Ready, Signal, –20, –10, Clip, and Thermal. The faceplate is marked 0 to 10 behind the pots, and the knobs can rest in any of 20 detented (notched) positions. This makes it easy to match channels in a hurry. Between the pots are an LCD window and pushbuttons marked Set/Enter, Prev/Up, and Next/Down for control of the built-in parameters.
The rear panel of theoffers a straightforward collection of XLR (input) and binding post (output) connectors with the addition of Speakon twist-lock connections on the outputs, and a HiQnet mini USB port to use with a computer and Crown software (described below). The input side also has male XLRs for line pass-through and for chaining amps. A diagram above the binding posts, which accept banana plugs, shows which posts to use for those who wish to use exposed-wire leads to connect speaker cables. Placement of the posts, with red "positive" posts next to each other and black posts on the outside, make it easy to use one banana plug when the amp is in bridge mode.
The unassuming power receptacle connects to an advanced Universal Tracking Switch Mode power supply, usually found only in much more expensive amps. Besides the fact that you can use the amp anywhere in the world (with the proper wall adapter), theintelligently computes the power needed based on the input signal. The resulting efficiency means you can put more amplifiers on the same circuit without risking an overload and shutting down your performance.
I wired up my passive JBL studio monitors to theand connected the amp to my 12-channel FireWire-equipped mixer. As I expected, the Crown amp was clean, quiet, and transparent when I pumped a variety of program material through it—from full-range orchestral music to bass-heavy techno-pop. Although I had used powered monitor speakers for many years, I was impressed with how easy it was to set up the lightweight 4002 and drive my speakers with 650 watts each instead of 100.
The DSP section of the 4002 includes five Quick-Start presets to help you get rolling. These are DSP Off, Bridge, Crossover (the channel outputs are split at 1.2kHz, which can be adjusted), Bridge Subs (the summed bridge output has a low-pass filter at 100Hz), and Subharmonic Synthesizer (low-pass filter and generated deep bass). Only the current DSP edits are retained when you power down and restart the amp. But you can store 15 user presets for instant recall using the free HiQnet Band Manager or System Architect software available at hiqnet.harmanpro.com. Crown also provides an Amplifier Application Guide PDF file at crownaudio.com to help you determine your system's optimum gain structure.
You can set the amp to stereo or bridge mode, set basic EQ's independently for each channel, set independent delays for each channel (each with 14 presets), or engage a limiter on one or both channels. (Channel 1 is always the active channel in bridge mode.) The limiting comes from Crown's new PeakX Plus, which provides greatly improved response and sound quality and gives you full control over threshold, attack, and release. You can also engage a subharmonic synth for deep bass. Crown has expanded this feature to double the bass frequencies to an octave below. (In the previous version of XTi, the frequency was locked at 90Hz.) Now you can change the frequency along with defining the max harmonic frequency and fully control the filters.
The 4002 brings big improvements to the already excellent XTi series. The new features bring ease and convenience to anyone who needs a hardworking, lightweight, and intelligent amp—or series of amps—to drive everything from a small studio to a mobile rig to arena tours.
Features & Specs
- PeakX Plus limiters provide full control over threshold, attack, and release
- Enhanced Subharmonic Synth section doubles bass frequencies and provides control over frequency, gain, and filter type
- 3 user-defined fan mode controls—normal, early, and full speed
- New system monitoring provides software visibility of AC line voltage and power supply temperature
- Increased number of presets to a total of 30; 29 user-definable
- Integrated cast-aluminum handles
- Locking power cord clip
- Updated HiQnet Band Manager and System Architect control software