One of the wonders of the digital audio revolution is the ability to simulate analog devices. From amplifier emulators to soft synths to plug-ins patterned after classic effects boxes, the practice of modeling is here to stay. And why not? By providing the functionality of more expensive or vintage gear without the price, rack space, or footprint associated with the real thing, well-constructed models can save recording engineers and desktop musicians heaps of money and space.
The Roland MMP-2 Mic Modeling Preamp figures into this lineage quite nicely. It promises users the ability to turn a small microphone collection into a veritable arsenal of microphones, with preamplifiers, equalizers, and dynamics processors.
The MMP-2 is roughly the size and thickness of a hardback book, but with a slightly sloping top panel to facilitate desktop usage (see Fig. 1). Analog inputs are provided on two combo XLR/TRS jacks on the upper left-hand corner of the top panel. Below each jack is a 20 dB pad switch and a rotary trim-control pot. The pots are labeled Sens (sensitivity), and the values given reflect the expected output level of the microphone (or other sound source) being used. Values range from -16 dBu to -64 dBu without the pad and from +4 dBu to -44 dBu with the pad engaged. (Some people may find this a little odd, as most preamp trims are marked by the amount of dB by which the signal is being amplified.) Below each pot is a tiny red peak LED that lights up when the input reaches a user-selectable level of 0, -3, or -6 dBfs. The default setting is -3, which affords a bit of headroom before digital distortion occurs.
Below the peak LEDs are two buttons (one for each channel) labeled, jointly, Phantom/Phase/Lo-Cut, which provide access to 48V phantom power, polarity reverse, and a highpass filter sweepable from 20 Hz to 2 kHz. The buttons select the functions, and parameters are adjusted using the three rotary value-control knobs beneath the LCD screen. In addition, pressing the Page button to the right of the LCD screen gives you access to the inaptly named Attenuator control. I say “inaptly” because, though it does allow attenuation of the signal by up to 42 dB, it also can boost the level by up to 6 dB. “Level” would be a better name for this control.
On the bottom left of the MMP-2 are two buttons, labeled Edit Ch Select, for selecting the channel you wish to edit effects parameters on. It's very handy being able to flip back and forth between the effects parameters of the two channels in order to compare settings and make quick adjustments. That feature is one of my favorite aspects of the MMP-2 — no parameter is ever more than a few button pushes away.
Another function of the Edit Ch Select buttons, referred to as Link mode, is enabled by holding down the button for channel 1 and then pushing the button for channel 2. That links the two channels into a stereo pair, after which all changes to the effects settings are applied equally to both channels. The Link feature affects only the DSP functions, though, and not any of the input controls (Pad, Sens, Phantom, Phase, Lo-Cut, Att). To get out of Link mode, you simply press either Edit Ch Select button. Whatever changes you made stay with channel 1, and channel 2 reverts to the state it was in before you linked the channels. That's a very clever feature — it allows you to experiment with linking the two channels but then change your mind at any point and instantly recall your previous channel 2 setup.
Yet another function accessed by the Edit Ch Select buttons is referred to as Channel Copy. The manual states that in order to copy all of the effects parameters (excluding those listed earlier) from channel 1 to channel 2, you hold down the channel 2 button for several seconds and then press Enter when prompted. But apparently the manual is mistaken, because I found the reverse to be true: pushing one channel's Edit Ch Select button for a few seconds allows you to copy that channel's parameters into the other channel, and not vice versa. That function can come in handy when you want the two channels to start out having the same set of effects but still be tweakable individually. You can't undo Channel Copy, so be sure you really want to copy before you commit to it.
Above the MMP-2's LCD screen are four cool-looking translucent buttons labeled, from left to right, Meter, Patch, System, and Enter. Each of the three leftmost buttons provides access to three different screens and glows green, red, or orange, depending on which parameters it is accessing. Pressing the Meter button makes the LCD screen display Input meters, Dynamic meters (compression or expansion gain reduction), or Output meters. (At first I missed having dedicated meters; however, I quickly became accustomed to them residing just a few button presses away.)
The Patch button's green, red, and orange hues correspond to Select, Store, and Reset, respectively. Those functions do just what their names suggest. Select allows you to choose 1 of the 43 preset patches, which are optimized for different sound sources (Violin, Wood Bass, Rock Male Vocal, and so on). The Store feature allows you to store your own settings into any of the 64 user patches or to reset the parameters of the currently selected patch. The only twist is that Reset completely zeroes out whichever effects you select (Model, EQ, Dynamics, Plug In, or all effects) instead of resetting them to the default state of the patch itself. In order to return them to the default setting, you need to reselect the preset or user patch using the Select function; however, that will overwrite all effects parameters for both channels.
Actually, that is my biggest gripe with the Patch function and perhaps even with the whole device: selecting a patch always affects both channels. There doesn't seem to be a way to select a patch for one channel while maintaining different settings on the other — a major drawback if you want to use two microphones on two different sources at the same time. Another thing that bugged me is that, after turning the value-control knob in preparation for selecting another patch, there is no way to tell from the hardware unit which patch is currently active. On a brighter note, one cool aspect of the patches is that you can see exactly what they do to the effects settings and make subtle changes from there. Note, however, that patches include effects parameters only, not input parameters such as Phantom Power and Lo-Cut. Also, although you can store Modeling parameters in your own patches, none of the preset patches contain any, and selecting a preset patch zeroes out any Modeling parameters you may have enabled.
The System button provides access to three sets of screens: Clock, USB, and Others. The Clock screen is where you choose the audio-input source (Mic or Digi), the clock source (Int or Digi), and the sampling frequency (44.1, 48, 88.2, or 96 kHz). You can choose only Digi as the clock source if the S/PDIF input is receiving valid clock. Moreover, you can choose only Digi as the input source if the clock source has already been successfully switched to digital, and once you are in digital-input mode, the unit obtains the sampling frequency from the source and renders the frequency selector inactive. Actually, I find these limitations quite useful — I have never understood why other digital devices let you select the improper clocking source if they are able to sense that there is no solid sync coming in.
The USB screen lets you choose the driver, the device ID, and whether you want to send metering information over USB to a computer. You'll probably want to leave these settings alone, unless you want to delve deep and set up the MMP-2 as a MIDI controller. The unit will, in fact, send MIDI data over the USB port, and the manual provides seven pages of very specific MIDI implementation data.
One more click turns the System button orange and brings up the Others screen, which comprises controls for the contrast of the LCD screen and Peak LED level; the Route control; system initialization; and backing up and recovering user patches to a computer using the USB port. You can adjust the contrast of the LCD screen over a range of values from 1 to 16, and at any value setting you have approximately a 20-degree viewing range. This is not a trivial matter — you'll need to adjust the contrast to suit your viewing angle. When I first placed the MMP-2 on my desk, all I could see was a completely black LCD screen. I had to prop the unit up with a wedge of foam so I could read the screen — until I discovered the contrast control.
The Route control allows you to set up the MMP-2 as a signal splitter, with the input signal showing up at both channels of the digital and analog outputs simultaneously. You can split the signal either pre-DSP, which allows you to retain control over the EQ and dynamics of the second output, or post-DSP, which lets both outputs come directly from channel 1's effects section. I can imagine a number of situations in which this feature would come in quite handy. For example, you could split a signal's frequency range, or you could feed four separate inputs at the same time.
From the Initialize screen (a subscreen of the Others screen) it is possible to reset all system parameters, all user-effects patches, or both to the factory-default state. The Backup screen lets you save all user patches to a computer, and the Recover screen lets you overwrite the existing user patches with a previously saved set. You can back up as many sets as you like, so at 20 KB a pop you have virtually infinite backup resources (on your computer's hard drive).
The fourth button, labeled Enter, lights red when you have changed a parameter that can be saved (although merely exiting the current screen saves most changes). This button is also useful as part of the unit's “dummy check” — when you turn on phantom power or choose to erase all of your user patches, a message comes up on the LCD screen asking if you really want to execute that action. You push the Enter button to answer yes.
The 20-character-by-2-line LCD screen on the MMP-2 is a nice deep orange with black lettering. When adjusted to the proper contrast, it is easy to read in any environment, no matter how well or poorly lit. Also nifty are the little decibel markings at the top of the LCD screen, which correspond to the meters (when they are visible). The three value-control knobs beneath the screen are flanked by two Page buttons, which let you scroll left or right when there are more than three parameters for a given screen. Though I generally deplore working with LCD-screen menus, I found the MMP-2's screen surprisingly navigable.
Below the LCD screen and its associated buttons is the Edit Select section, which contains eight buttons: four on the bottom, labeled, from left to right, Model, EQ, Dynamics, and Plug In, and an associated Bypass button directly above each of those. The Model, EQ, Dynamics, and Plug In buttons glow green when selected, and the Bypass buttons red. I like having dedicated hardware buttons for bypassing the effects stages — it makes it much easier to hear how the sound is being affected by the given digital signal processor. Of the four types of effects, only three can be used at one time. Model and Dynamics are always available, but EQ and Plug In share DSP resources, so those two sections cannot be active at the same time.
The MMP-2 provides a fairly diverse array of input and output options (see Fig. 2). Next to the power switch is the AC jack, which uses a standard IEC cable to bring juice to the internal power supply. From left to right, the other provisions are an AES/EBU Digital Out on an XLR connector, an S/PDIF digital output and input on RCA (coaxial) jacks, a USB B-Type (square) jack for connecting the MMP2 to a computer, a switch for selecting the nominal analog-output level (your choices are -16 dBu or +4 dBu, rather than the standard -10 dBV or +4 dBu), and two analog Line Out XLR connectors.
It is important to note that no audio passes through the USB connection to or from the computer. This connection is for exchanging control information with the MMP-2 Editor software and for updating the unit with future firmware releases or effects algorithms.
Speaking of the Editor software, I consider it the MMP-2's icing on the cake (see Fig. 3). It has an excellent graphic interface and is even easier to use than the unit's hardware controls. The software was also very easy to install (though familiarity with OMS or FreeMIDI, one of which is needed in order to communicate using MIDI with a Mac, is helpful). My only complaints are that the software doesn't provide control over the Plug In settings, and it doesn't allow you to select patches (although it does tell you which patch is currently active). Also, you must start the computer with the MMP-2 already powered up and connected over USB to get the Editor to recognize the hardware unit — which means if the unit somehow gets unplugged, you have to reboot to reestablish communication. In other words, contrary to what the manual says, the MMP-2 is not exactly “plug and play.”
I tested the MMP-2's mic modeler with an AKG C 3000 B — one of the mics recommended by Roland — as my input microphone. I compared the results with microphones that matched the somewhat vague descriptions of the MMP2's six models. For “small dynamic” I used a Shure SM57; for “vocal dynamic” I used a Shure Beta 58; for “large dynamic” I used a Sennheiser MD 421; for “small condenser” I used an Oktava MC012; for “large condenser” I used a Neumann U 87; and for “vintage condenser” I used a Neumann M 149 (a descendant of the M 49 and U 47, and the closest thing to a vintage tube condenser I could get my hands on).
I like that Roland kept the descriptions of the models generic — other companies' claims that their mic modelers can make an ordinary microphone sound like a Neumann U 47, a Telefunken U 47, or any other giant among transducers just seem ridiculous to me. The approach of providing fewer models with more generic descriptions is more realistic, not to mention hard to dispute.
So does a vocal track produced by a male singing through a C 3000 B and modeled to sound like a “vocal dynamic” sound just like it would through a Beta 58? Not exactly — but it does sound more like it than the C 3000 B with no modeling at all.
In general, on vocals, acoustic guitar, electric bass, and upright bass, though none of the microphone models sounded exactly like the actual microphones, they all had characteristics that approximated the sound of the target mics. Of course, that doesn't address the more important issue of whether the modeled sound was better or worse for a given situation. Indeed, to my surprise, the models sometimes sounded better than the mics they were modeling. For example, on one acoustic-guitar track, I much preferred the C 3000 B modeled as a small condenser to the actual small-condenser MC012 (my usual microphone of choice for recording acoustic guitar).
For the vocals tests, I generally preferred the real mics; then again, I was using Neumanns that cost thousands of dollars. For upright bass, I achieved the best sound for the particular track by using the C 3000 B with the large-dynamic setting (which shouldn't have surprised me, given that I often use a Sennheiser MD 421 or Electro-Voice RE20 on acoustic bass). The result was a nice, rich, and full — yet not boomy — tone. The bottom line is that achieving the best results involves a little experimentation with the many variables the MMP-2 affords — you can't just stay with what you think should work.
The MMP-2's 4-band fully parametric EQ was quite transparent and musical, sounding at least as good as any digital EQ I have used. Ditto for the dynamics processing, which includes compression and expansion as well as a switchable de-esser/enhancer.
As of now the only plug-ins on the MMP-2 are microphone-preamp models. I tested these by recording a full mix played on Genelec 1030As miked with a tiny-diaphragm measurement mic. Comparing the results proved an exercise in distinguishing subtleties. The difference between the Red7 (Focusrite Red) and the CSSlSt (Crane Song Solid State) presets, for instance, was pretty minimal. In general, the presets that model tube preamps sounded a little crunchier, especially in the cymbal range, as compared with the solid-state models, which sounded clearer and crisper — just as you might expect.
I do have a few minor gripes about how the MMP-2's various effects sections work. What bothered me most were bypass redundancies. Each section has both on/off and Bypass switches. The manual says these are functionally the same (except in the Dynamics section, where the Bypass switch bypasses all of the dynamics processors as a group and the on/off switches pertain only to individual effects). That means that for the Modeling and EQ sections, bypassing does the same thing as turning the effect off. Typically, a dedicated bypass button means that circuitry is taken out of the signal path. But according to Roland, physically bypassing any of the effects sections is impossible, given their DSP architecture. Okay, then — so why have both an on/off switch and bypass function? To add insult to injury, choosing the Flat modeling setting seems to do exactly the same thing as bypassing (or turning off!) the Modeling section. Redundancy for no apparent reason just irks me.
I also discovered what appears to be a small labeling mistake: the letters “BEF” show up on the LCD screen and in the Editor software for the Band-Reject Filter parameter. I suspect that that should have been “BRF.”
The Roland MMP-2 mic-modeling preamp is a very powerful tool, especially for personal-studio recordists with few resources. Will it really make your AKG C 3000 B sound as good as a Neumann U 87? No. But it can dramatically increase the available sound palette of the mics you do have. In addition, the MMP-2 offers good preamplification, high-quality A/D conversion, and better-than-average EQ and dynamics processing. The unit is easy to use, is very portable, and has a very small footprint. Granted, at nearly $700, it's not the best deal in the universe. But it probably won't break your bank either. If you are looking for the Swiss Army knife of digital front-ends, give the MMP-2 a good hard look.
Minimum System Requirements
MAC: G3/233; 128 MB RAM; Mac OS 8.6; OMS 2.3.5 or FreeMIDI
PC: Pentium II/200; 64 MB RAM; Windows 98/2000/ME/XP; USB port
FEATURES4.0EASE OF USE4.5AUDIO QUALITY4.0VALUE3.5RATING PRODUCTS FROM 1 TO 5
PROS: Impressive array of I/O options. Tons of sound-shaping capabilities. Relatively easy LCD-screen navigation. Handy stereo-linking function. Editing software is powerful and intuitive.
CONS: Can't select patches from editing software. No way to tell which patch is currently active from the hardware unit once you turn the knob. Patch changes always affect both channels — can't set up different patches for the two channels. Writing style makes the manual difficult to follow in places.
Roland Corp. U.S.
tel. (323) 890-3700
Analog Inputs(2) balanced/unbalanced ¼" TRS/XLR Neutrik combo connectorsAnalog Outputs(2) balanced XLRDigital Inputs(1) S/PDIF on RCA connectorsDigital Outputs(1) AES/EBU on XLR connectors; (1) S/PDIF on RCA connectorsNominal Analog Output Level-16 dBu or +4 dBu (switchable)Frequency Response44.1/48 kHz: 20 Hz-20 kHz (+0.1/-0.5 dB); 88.2/96 kHz: 20 Hz-40 kHz (+0.1/-3.0 dB)Signal-to-Noise Ratio105 dBEquivalent Input Noise-132 dBuA/D Conversion24-bit; 64× oversamplingD/A Conversion24-bit; 128× oversamplingSampling Rates44.1, 48, 88.2, 96 kHzPower SupplyInternal; 117, 230, or 240 VACDimensions9.9" (L) × 6.5" (H) × 3.0" (D)Weight4 lb. BIAS