Summit Audio MPE-200: ELEMENT 78 SERIES MIC PREAMP/EQUALIZERIn the periodic table, element 78 is platinum, and Element 78 is also the name of the new series of digitally controlled analog processors from Summit 10/01/1999 8:00 AM Eastern
In the periodic table, element 78 is platinum, and Element 78 is also the name of the new series of digitally controlled analog processors from Summit Audio. First in the series is MPE-200, a stereo (or dual-mono) microphone preamp with four-band parametric equalizer. MPE differs completely from other new pre/equalizer combinations in two important ways: One, Mr. Rupert Neve designed the Class A, discrete-transistor analog microphone preamp; coupling sections; output driver stages; and English-made transformers, and specified the frequencies and performance of the equalizer section. Two, the entire unit is digitally controlled, using an intuitive and simple interface designed by Summit engineers. Digital control allows all front panel settings to be stored internally in any of the 25 memories, or externally through a MIDI SysEx librarian. Digital control also means that there will never be any scratchy pots or switches to replace, and all settings can be exported by way of the rear panel MIDI ports to less-expensive slave preamp/equalizer units, such as the upcoming MPE-200S.
The unit I reviewed came with Version 1.23 software and differed (in a good way) from the pre-release spec sheets and other reviews I have read. Future updates (if needed) would be handled by your Summit dealer, who would connect a special computer interface to a port within the unit and download. Physically, the MPE-200 is a handsome and impressive unit that reflects professional confidence, from its thick extruded aluminum front panel and massive chassis components, large rotary-shaft encoder knobs and backlit LCD alphanumeric display switches to its 28-pound heft.
Operation of the MPE is easier to work than my friend's new BMW car stereo. LCD onscreen switches display the current accessible menu for that section of the unit, and pushing the switch itself toggles through the other available menus in an endless loop. Once the desired menu is found, a rotary-shaft encoder knob advances around the menu to the desired parameter, while turning that knob changes that parameter value. Furthermore, the switches' LCD screen changes color to indicate operational or setup modes. Thankfully, there are no confusing imbedded submenus or "trick" data entry schemes; the display switches show all data and the shaft encoders also indicate this information with backlit pointers at actual dial positions of frequency, Q, boost, cut, peak, shelf, fine or coarse gain settings.
MASTER OUTPUT/SETUP SECTIONI divide the MPE into three parts: the microphone preamp/filter input section; the parametric equalizer sections; and the master output/setup section. Let's begin with the master output/setup section, because when getting a sound I'll go to this section first to choose an unused preset memory location to be saved as I refine the sound. The Master LCD display switch has up to four menus: Master Channel Select, Master Preset, Master Setup and Output Fader. The Master Channel Select Screen indicates whether Channel A and B are "locked" or "unlocked" (more about this later) and has a dual-bargraph VU meter showing the EQ's output level. Output level is adjustable +/-16 dB to make up for the EQ's boost/cut settings. This entire screen flashes red with peaks of +18 dB or 3 dB below clip and is pretty hard to miss. Master Preset (a yellow screen) shows both the currently-loaded preset location and the preset that's waiting to be loaded. Here you can A/B compare your stored preset and today's tweak without losing either setting.
Essentially, settings are saved as a preset by "locking" them in. When locked, the preset can be altered but changes in the buffer will not be saved if power fails, the MPE is turned off or another preset is loaded. In Sleep mode, the buffer memory's contents are saved even when the MPE is powered down. Within Master Setup you can unlock and lock presets; select whether the MPE operates in linked stereo-where all settings track together on both channels-or 2-channel modes, where each channel can have completely different settings. You can also add a fader to the output of the equalizer-a useful feature for "on the fly" fade outs during direct recording. These fader settings are NOT saved, and values are returned to 0 dB when changing presets or powering down-a good thing.
PREAMP/FILTER INPUT AND EQ SECTIONSAt the front end of the MPE is the microphone preamp/filter input section. The green Mic Gain screen shows gain settings of both channels, and the dual-bargraph VU meter has a -28 to +9dBu range. Gain is in 1.0dB steps. A single setting stores both mic gains in stereo mode, while in 2-channel mode, gain settings can easily be offset when your matched pair of mics don't match up. The Mic Gain display switch changes to bright red at +18dB peaks.
The HP/LP Filter screen (yellow) provides any combination of two filters. The highpass has 17 steps from 25 to 320 Hz; the lowpass has 17 steps from 4 to 30 kHz. These are 12dB/octave filters, but become a single, steep 24dB/octave filter when selecting the same filter twice with the same corner frequencies; or you could configure two LP or two HP filters with two different corner frequencies for an unusual contour. An Input Setup menu handles chores such as phantom powering on/off, phase flip and whether the mic preamp output feeds the equalizer input or not. This is useful when inserting an outboard compressor between the preamp and the EQ section or for using the preamp and EQ sections separately. The rear panel has stereo pairs of XLR analog I/Os for the EQ and preamp sections.
The parametric EQ section has four bands. Each band's LCD screen switch is yellow when bypassed and green when active. When switching, I heard a relay clicking, verifying a hardwired bypass. There is no global EQ in/out switch on the MPE, although this switching is easily accomplished by having a blank preset ready to compare to your current settings. The Low band covers 17 frequency steps from 30 to 300 Hz with +/-16 dB of gain. Like the MPE's Master Output and Mic Input sections, all the EQ parameter values are displayed on both the backlit pointer collar around the rotary encoder knobs and the LCD switches. Pressing the Frequency Select knob changes the section from peaking to shelving characteristics. In all four sections, pushing the Boost/Cut encoder knob toggles between Coarse (2 dB) and Fine (0.5 dB) steps-great for mastering. The EQ's Low Mid section handles 100 to 1k Hz in 17 steps. This time, pressing the Frequency select knob changes the knob to Q selection. As indicated on the display switch, Q is adjustable in 17 steps from a Q of 0.60 (or 1.6 octaves) to 2.0 (or 0.5-octave). Perhaps it may be a little esoteric to fuss over a Q of 0.60 vs. a Q of 0.65; and so I would like to see a wider range of Q's offered here-such as from 0.40 to as high as 4.0. The High Mid section is the same as Low Mid, except frequency steps are from 500 to 5k Hz: There's plenty of overlap for the most important middle frequencies. The High section band covers from 2 to 20 kHz in 17 steps and has switchable shelf/peak operation.
IN SESSIONEqualizing both program sources and individual instrument and vocal tracks with the equalizer sections alone, I was impressed by the MPE-200's ease of control over spectral tonalities. There is plenty of boost and cut available, with high enough Q's for surgical removal or blatant EQ hyping.
As the two channels track together exactly, in stereo, there is never a question about whether both sides of a stereo mix have the same exact EQ-you know they do! A/B comparison is a practical reality, as you have instant response without having to set up two "identical" signal paths on a console and then switch between them. Switching or "morphing" between presets yielded no glitches, noise or "zipper" effects. Also, I always saved presets as stereo even if I only used one channel for recording vocals. By locking out Channel A, I could then use Channel B for the same vocalist with an alternate microphone, with a different mic gain setting.
Another useful feature is the red peak indicator. This unit is so clean, I never would know by listening that I am approaching clip.
Speaking of clean, the MPE-200 offers some impressive specs. Maximum output is +28 dB. Within the mic preamp path, THD is rated at less than 0.003% (40 to 16k Hz), at 8 dB of gain and with +26dBu output level. THD in the EQ path at unity gain is less than 0.003% (40 to 16k Hz), while output noise at unity gain with all EQ and filters switched out is less than -100 dB. Dynamic range is measured at 133 dB and equivalent input noise at 60 dB of gain is -128 dBu.
Using the mic preamp on a wide variety of sound sources revealed a very transparent and warm sound, reminiscent of a vintage Neve module, but clearer, cleaner and able to handle momentary peaks better when using hotter mic gain settings.
The Summit MPE units should appeal to anyone interested in simple yet elegant digital control of the highest quality analog. If you are interested in owning a future "classic" piece of fine recording equipment, and you're starting a collection of digitally controlled analog processors, then begin with the MPE-200 at $4,495 and add additional slave MPE-200S units at $3,995 each.
Summit Audio, P.O. Box 223306, Carmel, CA 93922; 831/728-1302; fax 831/728-1073; www.summitaudio.com.