Mike Collins provides some early reflections on TC Electronic's latest reverb unit and effects processor.
TC Electronic's new effects unit represents a new approach to reverb design based on their 'virtual space simulator' technology (see 'VSS Technology' box at the end of this review). The M3000 offers a mammoth selection of 250 single and 50 combined presets in ROM, including many of the favourites from TC's previous units. You won't run out of memory slots to store your own presets very easily either, as you not only get an internal RAM bank for up to 250 single and 50 combined user‑memories, but you can also store the same number again onto a standard PCMCIA card — very useful for taking your favourite setups from studio to studio.
The new algorithms offered are the VSS Reverb and Gate, along with TC's CORE (Coefficient Optimised Room Emulation) Reverb, Reverb 3, Delay, Pitch, EQ, Expander, Compressor, Chorus/Flanger, Tremolo/Panner, Phase and De‑Esser. Like the existing M2000, the M3000 features two separate processors which you can use in serial, parallel, dual‑input, dual‑mono, linked and pre‑glide modes. The M3000 also features 24‑bit resolution A‑D and D‑A converters, along with 16‑ and 20‑bit dithering for output to devices working at these lower resolutions.
Breaking with the more conventional black‑with‑grey‑buttons look, the M3000 comes in a 1U rackmount case with an attractive grey metallic finish — and black buttons. From the left‑hand side, the front panel sports a slot for a PCMCIA card just underneath the power on/off button, with a display area to the right of this encompassing a pair of LED PPM meters, a column of LED indicators for overload, sample‑rate and MIDI activity, and a parameter display area. This was the one feature I felt let the unit down somewhat — the parameter display is not really large enough to do justice to the number of parameters which can be controlled. It can also be a little difficult to read from an angle, although you can adjust the viewing angle from the Utility page if you are going to be looking from a particular angle a lot of the time. And, to be fair, the display is about as large as is practical on a 1U unit with as many buttons to accommodate as there are on the M3000.
Talking of buttons, there are six main groups of four buttons each, occupying the main part of the front panel to the right of the parameter display. The first column of buttons lets you set up the inputs and outputs, select the routing mode, adjust the input and output levels, and control various utility functions. a particularly useful feature here is the ability to alter the digital input gain — to raise the level of an incoming signal from a DAT which has been recorded too low, for example. The next two columns provide the recall and store buttons for the presets, and the Edit mode and bypass buttons for Engines 1 and 2, as the dual processors are known. The Recall and Store buttons each have a second function when the Shift button is activated — to recall a Wizard (a 'helper' to suggest a selection of suitable presets for your application) and to delete a preset. The next column lets you control the combined presets — which use both processors — and a further column of smaller buttons lets you quickly store and recall any of these combined presets. Buttons are provided in the last column to let you confirm operations, Shift to the secondary functions, and move the cursor between parameters or page up and down. One further button is provided to let you tap a tempo for the delays, while a large parameter‑adjustment wheel takes up the last bit of space at the far right of the front panel.
The rear panel has an additional power switch, an IEC mains socket, a pair of balanced XLR analogue inputs, a pair of balanced XLR analogue outputs, optical input and output sockets switchable between ADAT and S/PDIF formats, a phono connector for word clock (a phono‑to‑BNC adaptor is supplied), a pair of XLRs for AES‑EBU and a pair of phonos for S/PDIF digital input and output, plus MIDI In, Out and Thru connectors. All the audio connectors are gold‑plated, and any combination of (or all) the digital outputs can be used simultaneously. The M3000's internal clock is switchable between 44.1 and 48kHz operation. There is also a quarter‑inch jack for an external control input, via which you can connect a momentary pedal to the M3000. You can use the pedal as a bypass switch for either or both of the processing engines, or to let you tap a tempo.
The M3000's user interface is very straightforward, providing two edit modes — User and Expert. In User mode, you are only presented with half a dozen or so of the most important parameters you will need to edit, such as decay time. Expert mode, by contrast, provides a much larger number of parameters to control the effects, so you can play with early reflections or modulation settings to your heart's content, for instance.
Setting delay tempos is easy as well. When you hit the Tap button, up comes a parameter display showing the tempo in bpm; you can tap on the button or rotate the Adjust wheel to set the tempo. As well as delay tempos, you can also control the reverb decay and the chorus, flanger, phaser or tremolo speeds, and you can sync the M3000 to an incoming MIDI clock signal by simply holding the Tap button for 3 seconds. Another neat touch is the MIDI monitor window which lets you display incoming program changes, control changes, SysEx and notes.
The 'normal' display window, which you can think of as the M3000's 'home page', shows either the Recall Display for one of the effect Engines or the Combined Display, which you are returned to whenever you exit from any other display. This display holds a few of the most important parameters for each of the two engines with Engine 1 in the upper half and Engine 2 in the lower half of the screen. To recall a preset you just hit the recall key for Engine 1 or 2 and scroll through the presets using the Adjust wheel, pressing OK when you find what you want. Obviously it could take some time to scroll through all the factory presets, so TC have provided a useful index to these which you can bring up on screen by holding down the Recall key for a few seconds. This reminds you which preset types occupy which preset positions — so, for instance, you can see at a glance that the Gated Reverbs are in presets 205‑211. Combined presets, which are also available, consist of a specific presets in each Engine, with a defined Routing between these which is shown in the display.
I found more or less the perfect settings for a jazzy sax solo with a preset called 'Smokey Sax', and when I turned to the drums there was 'Puk Drum Ambience' just beckoning me!
But what if you are not sure which effects might suit your purpose best? In this case, the Wizard will help you out by suggesting a bunch of presets for you to try. Just press the Shift key before hitting any of the Recall buttons and the display will show the Reverb Wizard. Select various search criteria and the M3000 will choose a selection of the presets which correspond to these criteria. So, for example, you can choose between Music or Post‑production applications, then select the type of instrument or environment you want to work with, such as drums or ambience, and finally select the size of the reverb. At the bottom of the screen the display shows the number of presets corresponding to these criteria which have been found, and you can scroll through the list of these much more quickly than having to search the entire list of presets. I found this feature very useful — marvellously simple to operate and allowing for very fast initial choices.
The Setups section has four buttons which take you to the Input/Output page, the Routing page, the Levels page, and the Utilities/MIDI settings page. The I/O page is very easy to use. You can see everything at a glance and make your choice of analogue and digital formats, clocking, sync and dither settings, and whether the optical connectors will deliver S/PDIF‑ or ADAT‑format audio. The Levels page also lets you see everything at a glance: you can select between +4dBV and ‑10dBu for input and output independently, or fine‑tune these levels in 1dB steps to match to just about anything. You can even boost the digital input level by up to 6dB. The Utilities and MIDI settings don't allow you to see everything at a glance, and scrolling can get a little tedious. Still, everything you need is there, from the display viewing angle to a PIN code setting which you can use as a security lock for the unit.
The Routing page is also extremely simple to use, letting you choose between the six different ways of hooking the two Engines up, but deserves a more detailed explanation:
- Serial mode is a stereo in/out routing giving you two independent effects in the same signal path, with the output from Engine 1 fed to the input of Engine 2. So, for example, you could connect a de‑esser, a compressor or chorus in Engine 1 and a reverb or delay in Engine 2.
- Parallel mode is another stereo in/out routing, where both engines work as stereo effects and both their stereo outputs are mixed into one stereo output signal. With this routing, the M3000 can be used as two parallel effects on the same stereo source. You may also set the I/O menu to left‑only input to get two independent stereo out effects from a single send on your mixer.
- In Parallel mode you can also use the Dynamic Morphing function to morph between the two Engines' output according to your input level, allowing quick, seamless effect changes. You could, for instance, use this to increase the room size of the reverb from verse to chorus if the vocalist sings more softly in the verse and more loudly in the chorus, by setting the threshold and speed of the effect appropriately.
- Dual‑Input or Split Mode is a dual mono in/stereo out routing. The left input is always routed to Engine 1 while the right input is routed to Engine 2. This allows you to set up two different effects each with separate inputs by connecting aux 1 from your mixer to left in and aux 2 to right in. Now you have access to two separate effects with a common stereo output, and you can set the individual preset output volumes to get the desired balance between these effects. With this routing you only need one set of return channels on your mixer.
- Dual Mono mode lets you split the M3000 into two independent mono effects units using left in/out for Engine 1 and right in/out to connect Engine 2.
- In Linked mode, the two Engines will link together to perform true stereo operation, one on the left channel and one on the right. This means that the preset in Engine 1 will be copied into Engine 2 and the edit pages will lock together.
- With Preset Glide routing, the M3000 will perform preset changes by crossfading the current effect and the new preset with a glide time which you can set using the Utility menu. This gives you a very smooth change between effects — allowing, for instance, a delay to keep repeating while a chorus is being faded in.
Fancy technical features are not going to make you buy the M3000 if you don't like the 'sounds' — which, for many people, will mean the presets — and I don't think anyone is going to be disappointed here. TC have prepared presets to get you started in just about any situation. For instance, I found more or less the perfect settings for a jazzy sax solo with a preset called 'Smokey Sax', and when I turned to the drums there was 'Puk Drum Ambience' just beckoning me! This is an emulation of the sound of the drum room at Puk Studios in Denmark, renowned for sophisticated rock rather than for punk sounds.
Although the reverbs will be the M3000's main selling point, it does offer a wide range of other time‑based effects and dynamics processes.
The four basic reverb algorithms together offer an extremely wide range of reverb effects. The VSS Reverb and Gate algorithms have separately controllable parameters for the reverb itself (decay time, mix level and so forth), the early reflections (type, balance and so forth), the reverb tail (high, mid, low decay times and so forth), modulation of the reverb tail, and 'Space Modulation' which controls the way the sound moves around the room. These new algorithms are what make the M3000 stand apart from the competition for me, providing new levels of realism and offering wider ranges of effects than others. The CORE algorithm, on the other hand, is still very good at short to medium decay times, although it doesn't have the VSS algorithm's Expert layer with additional control parameters. Similarly, the Reverb‑3 algorithm is taken from the M5000 and is very good at medium decay times.
Although the reverbs will be the M3000's main selling point, it does offer a wide range of other time‑based effects and dynamics processes. The Delay effect allows delay settings up to 1350mS, with feedback, and offers damping of the higher frequencies being fed back, for a more natural‑sounding delay effect. The Pitch presets let you create six differently‑pitched 'voices' at the same time — yielding some pretty awesome chorus effects. The EQ programs are 3‑band parametric types with separate high and low shelving bands while the standard LFO‑based effects (Chorus, Flanger, Tremolo and Phaser) are all very useable in a variety of situations.
The dynamics algorithms include an Expander/Gate to reduce noise in the channel, a Compressor to keep the signal at a more constant level and a De‑esser for reducing the sibilant sounds from vocals. All these effects work well enough, although I won't be throwing away my dedicated dynamics processors just yet!
For me, the M3000 is TC's most exciting new product since the 2290 Sampler/Delay, and I feel sure it will be able to offer some serious competition to the popular Lexicon models — it is actually priced a little lower than the PCM 81 and 91. Of course, other companies make high quality multi‑effects processors too — Yamaha, Sony, Eventide, Alesis et al, all make excellent‑sounding units of this type — but when it comes to purely reverb, most listeners would agree that Lexicon have always been a cut above the opposition. The new TC unit is certainly of that same calibre and, I believe, even has the edge. Given that it also scores heavily on ease of use, it should prove to be a real winner.
Digital audio's distortion performance is at its poorest at the bottom end of the dynamic range, where quantisation errors are most noticeable. By adding a so‑called 'dither' signal, consisting of very low‑level random noise, the audible effects of quantisation errors can be reduced, thereby minimising the distortion which normally occurs as the wanted audio signal reaches the lowest levels.
Of course there is always a trade‑off between the dither noise you are adding and the lessening of the distortion which this brings about. Various dither algorithms have been devised to try to provide the best compromises, the more sophisticated of which use 'noise‑shaping' techniques to remove noise from the middle of the audio spectrum where the human ear is most sensitive, shifting them into a less audible frequency range. The basic form of dithering which simply adds a low‑level 'white' noise signal is sometimes referred to as 'simple dither' to distinguish it from these more sophisticated systems.
The most important things you need to know are these:
- Dithering is normally used when truncating signals from 24 or more bits down to 16 or fewer bits, to help you to get the best possible subjective performance from the available bits when transferring audio digitally between systems.
- Simple dither adds a small amount of extra noise but reduces distortion of low‑level signals.
- Noise‑shaped dither should only be used once, immediately prior to mastering to CD or whatever, as repeated applications of this process can adversely affect the audio quality.
The M3000 uses the intriguingly‑named 'High Passed Triangular Probability Density Function', or HPTPDF for short, to work its particular dithering magic. TC's Thomas Lund explained this further, saying "We have kept away from using 'aggressive' noise‑shaped dither which can be problematic when you want to process your audio later on. The HPTPDF is a high‑pass filtered noise signal which is used instead of simple white‑noise dither. This is much more 'production‑friendly' — it doesn't conceal as much noise as the noise‑shaped algorithms but is more forgiving later."
As fate would have it, the day the M3000 arrived a very experienced ex‑Sarm recording engineer, Renny Hill, called by to see me just as I started checking out the presets. I was playing a Pro Tools session through my 02R with the Lexicon Lexiverb plug‑in installed in Pro Tools, a TC UNIT*Y card installed in the 02R, and the M3000 hooked up via the Aux sends from the 02R. The UNIT*Y is basically an M2000 on a card — ideal for comparison with the M3000 — while the Lexiverb in Pro Tools and the built‑in reverb in the 02R would provide other good comparisons. We tried out saxophone, drums, bass and various keyboards through all four reverbs, choosing roughly similar types of reverb presets. The 02R's onboard reverb sounded OK, but reminiscent of the original SPX90 reverb, sometimes sounding too metallic or 'honky' for my liking. For me, the Lexicon plug‑in sounded smoother and more interesting in many ways, while the UNIT*Y was fuller‑sounding and more realistic than either of these. Renny said. The presets in the UNIT*Y sound very suitable straight away. You have to play with the Lexicon more to get useable settings, although the Lexicon does sound pretty good as well."
Then we listened to the M3000. Before I could say anything, Renny quietly said "This sounds better than a Lexicon 480L!" I asked him why and he told me that the sound of the reverb was simply one of the most natural he had ever heard from a digital device. We switched back to the UNIT*Y and we both agreed that it sounded very natural compared with the Lexiverb and 02R reverb. But then when we listened to the M3000 again, the difference became much more apparent to me — there was a depth, a smoothness, but, more importantly, such a convincing and realistic sound to the reverb that we just stood around with our mouths wide open for the next 10 minutes while we just listened! Say no more!
- VSS Reverb
- VSS Gate
- CORE Reverb
- Reverb 3
TC Electronic have made great play of the new Virtual Space Simulation technology which powers the M3000. According to the brochure, it aims to provide "the ability to simulate the sonics of actual rooms", "the ability to keep the signal in 100 percent correct pitch, even when engaging extensive effects processing", and offers "to keep the signal 100 percent free of sound‑deteriorating modulation" perhaps most importantly, detailed control of early reflections is also possible.
TC's Program Manager, Thomas Lund, translated the marketing blurb for me, saying "Previous reverb designs added some modulation in their diffusion system. We found that, from a natural point of view, this is not correct. It is just a way of designers overcoming limitations of processing power. So we wanted to do it the way it should be, without these modulations and consequent pitch‑changing. The pitch‑changing was the most intrusive problem, as this does not happen with real reverb in a room. Now that there is no pitch change between speakers, say on a solo piano sound, our new reverb algorithms also deliver much better stereo imaging than was possible previously.
"However, sometimes this modulation and pitch‑changing can be subjectively desirable, as with the old EMT 250 plates which people love. These add a lot of modulation which people like for rock and pop. So we now offer the modulation‑free natural reverb settings plus the vintage‑type settings which do include these modulations in the M3000. We also researched the initial reflection patterns. We wanted to add different directions rather than just having reflections to left or right. We now have eight different directions for the reflections, which are combined across the stereo output. Each of these reflections can have individual EQ, delay, level and phase settings, providing a much greater degree of control than on our previous designs."
- Zillions of presets.
- Incredible‑sounding reverb.
- Dual processors can be combined in many different ways.
- Very reasonable price.
- My main gripe is the small display area available for the control and editing parameters, especially in Expert mode.
The M3000 sounds, at least to my ears, better than the closest competing product and costs around 20 percent less too. It is incredibly easy to operate and you get a tremendous selection of presets to work with. The new reverb algorithms are the most natural‑sounding I have ever heard.