L2 ULTRAMAXIMIZERA professional mastering limiter punches up your tracks.Waves' L1 Ultramaximizer software plug-in is one of the few audio tools I rely on that doesn't have a "sound" of its own. This mastering/compression program is essential for getting the most out of the 16-bit CD format. During the last five years, it has been one of the most important components in my studio.
Needless to say, I was enthusiastic about the new hardware version of Ultramaximizer, the L2. I used the L2 straight out of the box, because L1's familiar features were retained more or less unchanged. In addition to the advantage of real-time (as opposed to file-based) processing, L2 offers a handful of exciting new options that don't mess with the proven success of Waves' Increased Digital Resolution (IDR) technology.
These options include support for 24-bit, 96 kHz digital audio, excellent 24-bit A/D/A conversion, 48-bit internal processing, individual left and right analog-input controls, auto-release circuitry, dual-mono or stereo operation, and a hardwired bypass. L1's only feature that was not handed down to L2 is the ability to output 8-bit audio, which is pretty much limited to multimedia and Web-based audio.
MAX HEADROOMFor those not familiar with Waves' Ultramaximizer, here's how L1 works. The L1 Ultramaximizer plug-in combines output-level normalization with look-ahead limiting - a process that lowers amplitude peaks that come in above an adjustable threshold - and intelligently redraws them to minimize audible distortion.
As the threshold is adjusted downward from 0 dB FS (the maximum value, or ceiling, for any digital signal), more peaks are limited and the signal's dynamic range is reduced. Consequently, more headroom is created, and the normalizing function - which is typically set to keep peaks around the 0 dB maximum - effectively pushes the signal's overall gain up as the threshold decreases.
Besides its obvious gain-maximizing function, L1 also provides adjustable bit-depth reduction in addition to dithering and noise-shaping options to audibly enhance the low-level information stored in the digital signal's least significant bits. As a result of Waves' proprietary IDR process, the subtle aspects of a mix - room sound, reverberation, quiet instruments, and extreme high and low frequencies - are brought out of the background without the unwanted artifacts of nonlinear distortion or quantization noise.
I use L1 on nearly every mastering and editing job, and my clients are consistently amazed at the depth and resolution it adds to a mix while boosting their music to the level of most commercial CDs. On live recordings, analog-tape transfers, and other difficult reclamation work, L1 frequently works miracles; even on an average mastering day, it makes me look like a hero.
OUTBOARD FOR GLORYFor all L2's sophistication, the 2U front panel is a marvel of simplicity and makes this unit a joy to operate (see Fig. 1). The white-on-black control labels are easy on the eyes and large enough to read at a distance. The same goes for the numerical readouts and colored status LEDs. Best of all, the unit has no master LCD and no banks of menus to scroll through.
On the left are seven buttons, one for each processing parameter or I/O option. The buttons toggle through the available settings, which are clearly indicated by orange or green status LEDs arrayed to the buttons' left.
The buttons control input selection (AES/EBU, S/PDIF, analog); synchronization (external, digital, internal); sample rate (44.1 or 48 kHz); sample rate 52 (for 88.2 or 96 kHz operation); bit depth (16, 18, 20, 22, 24); dither (type 1, type 2, off); and noise shaping (ultra, normal, moderate, off).
The center-detented, analog-input gain controls range from -10 to +10 dB. To the right of the gain controls are three pairs of large, one-inch rotary control knobs, each with a yellow numerical LED and multisegment gain meters with automatic peak hold. The knobs control different parameters for each channel independently. The first pair adjusts the L2's threshold downward from 0 dB FS in 0.1 dB increments, and the meters indicate the input-gain level. The next pair, called Out Ceiling, controls the final output level (again in 0.1 dB steps downward from 0 dB), and their meters indicate output gain. The third pair governs release time and the knobs are adjustable over a range of 0.01 ms to 1 second. The associated meters indicate the amount of gain reduction.
To the far right is a pair of switches that activate the L2's auto-release function for each channel. Additional switches that engage stereo or dual-mono operation, bypass mode, and meter peak-hold reset are located in the center strip between the individual channel controls.
The front panel had one minor problem: the tips on some of the buttons were loose and wobbly. In fact, a few came off upon examination. The switch mechanisms are recessed below the panel, and without the tip, they could be accessed only with a small, pointed tool. Waves has confirmed that this problem has since been corrected.
The power switch and all connections are on the rear panel (see Fig. 2). Analog I/O is available on XLR and 11/44-inch jacks, but at +4 dBu professional level only. Balanced or unbalanced signals are accepted on both types of input connectors. On the outputs, the XLR jacks are balanced and the 11/44-inch connectors are unbalanced. The L2 has no -10 dBV semi-pro connectors.
Inserting a 11/44-inch plug at the input interrupts any signal present in the XLR connector. However, I found that some crosstalk from the XLR input was easily heard when both jacks were connected, prompting me to manually disconnect the XLR cable.
As noted earlier, the supported digital signal formats are AES/EBU (XLR) and S/PDIF (RCA), with input switching on the front panel. Both digital outputs are active simultaneously, which is a big advantage in a studio or mastering situation. Latency is rated at a low 1.5 ms. The unit's all-metal chassis is vented on both sides because it runs rather hot.
MANUAL DEXTERITYThe L2's manual is an exemplary document that not only explains all functions and potential applications thoroughly, but also provides detailed theoretical information in a straightforward, easy-to-comprehend manner. Most important, the manual stresses that the L2 should be the final processor in a digital signal chain, located immediately before the destination device, such as DAT, CD, or computer.
The manual also scores points by warning users against "slamming" mixes prior to mastering. There is no undo on a hardware processor, so prudent use is advised to avoid the typical pitfalls of over-compression. The L2's most sensible applications include maximizing levels from a DAT (or other master) to CD or cassette reference copies for clients, or as a high-quality, analog-to-digital converter with conservative limiting.
NORMALIZING RELATIONSI tested the L2 as a mastering compressor on a CD project by the band Cranium. I placed the L2 between my TC Electronics M2000 (used for parametric equalization with 24-bit output) and my digital audio workstation, and I adjusted the L2 on a song-by-song basis to boost overall gain within a range of 4 to 7 dB as tracks went to hard disk.
At these settings, some compression was audible on the snare and hi-hat, which stuck out dynamically from Cranium's wall of distorted guitar and bass. But the L2 dealt with these transients mercifully and yielded fine results. For example, running the mix through the L2 increased the guitar bed's level and intensity compared to the original, unprocessed DAT mixes. Once I auditioned everything from the computer, I was pleasantly surprised to find that overall levels were consistent. Only two songs out of nine needed additional minor gain adjustment.
I had similar success using the L2 on other mastering projects. It was a great time-saver compared to the file-based processing of L1, and I adjusted levels with confidence on any collection of mixes featuring consistent production and arrangements.
On one occasion, the L2 saved the day, providing left/right channel balancing and massive - yet very clean - gain boosting of an extremely low-level concert recording. On the other hand, I would be nervous about using the L2 for mastering a multiple-source compilation or for a job where levels, instrumentation, or dynamics vary widely. Under these conditions, I would prefer L1's ability to instantaneously compare processed and unprocessed material in the computer.
ALL IN ONEIn the recording studio, I pulled out the L2 for a broad range of jobs, and it soon became the digital equivalent of a well-stocked toolbox. When faced with impending deadlines and short sessions, the L2 kept me from getting bogged down by the time it takes to use the computer for mastering compression. CD copies of unfamiliar material were handled smoothly and efficiently by the L2 with a touch of set-it-and-forget-it limiting to avoid unforeseen digital overs. The unit's analog I/O also did a first-rate job of sample-rate conversion. For example, I converted 48 kHz material from a DAT tape to 44.1 kHz for burning a reference CD.
To critically evaluate the L2's sound, I put together an analog-multitrack mix from the dub-oriented Guerrilla Hi-Fi project produced at my studio by engineers Eithen Fletcher and John Finkbeiner. I used an Apogee PSX-100 for the initial 24-bit A/D conversion and recorded samples of the mix to a DAT machine running at 48 kHz. I tried the L2 in several different configurations: out of the signal path altogether; with the L2 between the PSX-100 and DAT machine, but bypassed; and active at threshold settings of 0, -3, and -6 dB using dither types 1 and 2.
There was no noticeable difference in sound with the L2 in or out of the signal path, and I heard only a slight, beneficial emphasis in the high-end detail of the hi-hat with the Ultramaximizer set to 0 dB limiting. At the -3 dB threshold, limiting was minor and generally confined to snare-drum hits, with no audible compression effects. With the threshold at -6 dB, the mix reached a fairly robust level that was certainly on par with most commercial CDs. At this setting, only the percussive guitar "skanks," drum fills, and some full horn chords were audibly limited, despite the meters' indication that most of the mix's dynamic peaks maxed out between -2 and 0 dB.
This is called brick-wall limiting. The L2 Ultramaximizer's performance at this extreme setting was still very musical, distortion-free, and, for much of the mix, absolutely undetectable. The L2's auto-release function worked marvelously throughout these trials and certainly deserves part of the credit for the device's transparency.
Next, I took the PSX-100 out of the signal path and used the L2 for A/D conversion as well as limiting. The resulting timbre was very close to that of the Apogee converters; much closer, in fact, than any other digital processor or recorder I've tested. The main differences included a slightly grainier upper midrange in the hi-hat and trumpet and an occasional harshness from the limiter in the most densely compressed sections at the extreme -6 dB threshold setting. Regarding other important factors (such as resolution, frequency response, sound stage, and noise floor), the two converters were evenly matched, and there were no significant differences.
UNLIMITED POTENTIALBased on my experiences with the L2, I would seriously consider adding one to my studio inventory. In fact, the more I used it, the more reasons I found to keep it close at hand. The unit sets up quickly and easily, and it provides a logical front-panel layout of dedicated switches and knobs that governs all functions. In addition to being a snap to use, the L2 is an extraordinarily versatile processor. With its top-notch A/D converters, high sample-rate and bit-depth capability, and multiple digital outputs, this unique device integrates seamlessly into any two-track mixing, mastering, or transfer scenario.
An experienced mastering engineer can rely on the L2 Ultramaximizer to make a mix jump out of the speakers, and in less time than the L2's computer-based predecessor. It's also invaluable as a limiter during unpredictable tape transfers, live two-track mixes, and location recordings. When used sensibly to beef up demos or reference CDs, the L2 is so good, it's addictive.
Of course, all this power doesn't come cheap, and it's unfortunate that the only real drawback of the Ultramaximizer is its rather steep price tag. But the cost of this fully professional unit is insignificant compared to its ability to dramatically increase sound quality while pushing your stereo mix levels up to the ceiling.