More than just another stand-alone box that burns CD-Rs, the Alesis MasterLink also includes a large hard drive to store audio and built-in CD mastering tools -- in theory, all you need to create CD-R masters without ever booting up a computer. Paul White puts this idea to the test.
Creating your own CD is easy these days --pretty much any computer equipped with a CD-ROM burner can do the job. However, you also need suitable software and a high-quality audio I/O unit that can handle both analogue and digital material, and you may additionally require software mastering plug-ins. If you already own a computer, this is probably the best way to make your own CD-Rs, but if you don't, is there an alternative? You can copy DAT mixes straight to a stand-alone CD recorder, but this doesn't allow you to perform vital operations such as trimming the starts and ends of the songs, adjusting levels and EQs or creating precision fades. Nor will you be able to chop up different mixes and reassemble them to create a new arrangement.
The Alesis MasterLink doesn't offer all the facilities of a computer-based CD editing and mastering system, but it does provide a neat, one-box solution for compiling your finished mixes onto CD with a few processing tricks thrown in along the way. It also allows you to create CD-ROM backups of high-resolution audio recordings made at up to 24-bit resolution and a 96kHz sample rate, which may become increasingly important in the future (see the '24/96 Compatibility' box on page 129). Add DSP capability for EQ, compression, limiting and normalising, the ability to trim the starts and ends of songs and the means to create fade ins and outs with a choice of curve types, and you have a pretty powerful package.
Cosmetics & Features
The hardware occupies a 2U box and is based around an 8x read, 4x write CD-burner and a non-user-specifiable 4.3Gb internal hard drive, which is large enough to hold several albums' worth of CD-quality stereo audio at the same time. Audio is first recorded to the hard drive, then assembled in a playlist where the track starts and ends can be trimmed, appropriate between-track gaps set
ALESIS MASTERLINK £1499
One-box solution to CD mastering and burning.
Built-in DSP-based processing.
Can archive and play 24-bit/96kHz audio.
Unsuitable for cut and paste rearranging within songs.
No Undo button.
No non-destructive track length changes possible.
A complete stand-alone solution for anyone who needs to produce Red Book CDs from master DAT tapes or other sources, MasterLink is also 24-bit, 96kHz-compatible. It is currently less suitable for chopping up and rearranging songs at the mastering stage, though future software revisions may change this.
Cosmetically, the Alesis MasterLink looks much like a stand-alone CD recorder and has both balanced XLR and unbalanced phono analogue I/O as well as AES-EBU (XLR) and S/PDIF (phono co-axial) digital I/O. The converters are 24-bit with 128x oversampling and a specified signal-to-noise ratio of better than 113dB (A-weighted). 44.1kHz, 48kHz, 88.2kHz and 96kHz sample rates are supported.
There's no hardware input sample-rate conversion, but if you're making a Red Book audio CD, any high sample rates or bit depths will be converted down to the Red Book-standard 44.1kHz sample rate/16-bit resolution automatically as the CD is burned. If the resolution of the original audio file is greater than 16-bit, noise-shaped dither will also be applied to maximise the dynamic range of the final recording. This process doesn't change the audio on the hard drive, which remains in its original format. A motorised CD drawer accepts standard CD-R discs, but MasterLink does not read or write CD-RWs.
At the centre of the front panel is a large, clear plasma display which shows track and playlist details, edit parameters, time and the audio data format as well as providing stereo metering. Conventional CD writer transport controls occupy the right of the front panel while the rest of the space is given over to groups of buttons that deal with various aspects of the recording, editing and CD burning process. Most of these are located below the display with the central oval group of buttons functioning as cursor and yes/no keys. The keys below the CD drawer deal mainly with the digital format of the recording and the single Create CD button does exactly that There are four stereo DSP functions in all -- the DSP1 Compressor, DSP2 EQ, DSP3 Limiter and DSP4 Normaliser. DSP1 is a fairly conventional, full-band compressor with threshold, ratio, makeup gain, attack, release and hard/soft knee action as well as peak or RMS side-chain detection. It won't replace a multi-band mastering compressor, but it works perfectly well. DSP2 is a three-band parametric equaliser where the high and low bands may also be switched to shelving mode. It offers ±18dB of range over a 20Hz to 20kHz range. The Limiter is slightly more advanced than its analogue counterparts as it can look ahead to anticipate signal peaks, and may be used to increase loudness by limiting the top few dBs of a signal and at the same time increasing the level, rather as the Waves L1 plug-in does. Again, it is a single-band limiter, but it works well and is easy to set up with just Output Level, Limit Threshold and Release parameters. If more than five or six dBs of limiting are applied, you may hear the Limiter working, but it's generally smooth and well behaved. Finally comes the Normaliser which first scans the track to find the highest peak, then applies a real-time scaling function so that the loudest peak is at digital full scale. All four DSP functions may be set up independently for each track, making it possible to match the tonality, level and dynamic range of each track on an album. Track fades are applied after all processing except normalisation so that the compressor and limiter action are not affected as the level fades in or out.
Mastering Tools -- The DSP Functions
The DSP functions of the MasterLink can be auditioned in real time, though as explained in the main text, you must create (or 'render') a disk image before you can burn a CD where one or more tracks are processed using a DSP function. No user intervention is required to make this happen -- MasterLink does whatever is necessary, burns the disc, finalises it, then pops it out ready for you to take away.
There are four stereo DSP functions in all -- the DSP1 Compressor, DSP2 EQ, DSP3 Limiter and DSP4 Normaliser. DSP1 is a fairly conventional, full-band compressor with threshold, ratio, makeup gain, attack, release and hard/soft knee action as well as peak or RMS side-chain detection. It won't replace a multi-band mastering compressor, but it works perfectly well. DSP2 is a three-band parametric equaliser where the high and low bands may also be switched to shelving mode. It offers ±18dB of range over a 20Hz to 20kHz range.
The Limiter is slightly more advanced than its analogue counterparts as it can look ahead to anticipate signal peaks, and may be used to increase loudness by limiting the top few dBs of a signal and at the same time increasing the level, rather as the Waves L1 plug-in does. Again, it is a single-band limiter, but it works well and is easy to set up with just Output Level, Limit Threshold and Release parameters. If more than five or six dBs of limiting are applied, you may hear the Limiter working, but it's generally smooth and well behaved. Finally comes the Normaliser which first scans the track to find the highest peak, then applies a real-time scaling function so that the loudest peak is at digital full scale.
All four DSP functions may be set up independently for each track, making it possible to match the tonality, level and dynamic range of each track on an album. Track fades are applied after all processing except normalisation so that the compressor and limiter action are not affected as the level fades in or out.
One very important control is the HD/CD button at the top right-hand corner of the panel. HD mode is for recording or playing back via the internal hard drive and when burning CDs, and CD mode is used when the MasterLink is playing back standard CDs or copying CD tracks to the internal drive. Depending on which mode is selected, the display and the transport control operation will change. However, other than the up/down cursor buttons, which also operate as yes/no buttons, all the controls have a single, dedicated function. All the front-panel controls and functions are duplicated on a hand-held remote, which is useful, although the size of remote and its buttons makes using it a little fiddly.
A utility menu allows for formatting the drive, sorting audio files alphabetically and changing the meter ballistics. It also shows the current software revision, which stood at v1.00 on the review model.
How It Works
To make a recording, you either need to select the analogue or digital input source, or import a track directly from CD. Both digital inputs are operational at the same time, so it's important to plug into only one of them. If the source is digital, the data storage format will clearly be the same as the original, but if it's analogue, you can set the bit depth and sample rate. Note that if a digital source is selected, the playback sample rate will be controlled by whatever digital source is connected, so if you open a file that was created with a different sample rate, it'll play back at the wrong speed unless you either select an analogue source or unplug the digital input.
Audio must be recorded into a playlist and 16 playlists are available plus a further Special playlist location for storing rendered image files. Playlists can be named, as can tracks within them, but there's no input for a keyboard, so names have to be entered using MasterLink's front-panel buttons, which means it's rather like naming patches in a synth -- easy but slow.
Most computer-based systems use a file and region system that enables recorded sound files to be divided into regions, such as tracks or sections of tracks. The MasterLink doesn't work that way -- instead, songs are recorded individually, each being saved as a track in the currently open playlist. You can't divide a chunk of audio after recording, though you can trim it to length. Note, though, that trimming is a destructive process, and for some reason, there doesn't seem to be an Undo function -- so if you snip a little too much off your audio, there's no going back.
Once material is in the playlist, you can audition it, rather like playing the tracks on a standard CD, complete with track skip buttons and fast forward/reverse functions. It's also possible to record additional tracks, up to a maximum of 99 per playlist. Unwanted tracks may be deleted and tracks may be moved to a different order via a simple source number/destination number system. Track-to-track spacing may also be changed here, as may the level of individual tracks (over a ±18dB range), and once you're sure a track is OK, it may be locked to save accidental deletion or editing. Fades are all carried out non-destructively and in real time -- all you have to do is select fade in or out, set the fade length and choose from log, linear or inverse log fade curves.
DSP settings may also be made for individual tracks -- you just hit the track DSP button as many times as it takes to bring up the desired DSP effect, use the Up/Down buttons to select the parameter to be adjusted, then move the cursor across to the parameter value and edit it using the up/down buttons. It seems you never have to save anything -- you just set things like fades a
MasterLink normally burns audio CDs as Red Book-standard discs, which means they'll play on ordinary CD players, and should be acceptable as masters for commercial CD production. If you want to save a playlist where the material was at a different rate to audio CD, it is stored in something Alesis call the CD24 format, which is in fact a CD-ROM format rather than an audio format. CD24 recordings can still be played back by MasterLink as well as loaded into any computer editing system that supports that bit depth and sample rate. This is an important facet of MasterLink, as it provides a practical means of archiving 24-bit, 96kHz audio (or other non-Red Book standard formats). To produce a CD24 disc, the CD Format switch under the CD door must be switched from Red Book to CD24, and as you might expect, the amount of audio you can get onto a disc is reduced. A 24-bit/96kHz stereo recording times out at just over 19.5 minutes of audio on a 74-minute CD blank. When CD24 discs are created, track names (if used) are preserved, though they are all converted to upper case.
Track lengths cannot be directly edited from the playlist -- you must first go to the track edit mode and use Crop to trim the start and end to the desired positions. A type of slow audio scrub function makes it reasonably easy to find the right places to crop -- you hold down the Track Start or End button while using the transport Scan buttons, then press Track Start and Track End buttons together to make the edits. As pointed out earlier, this is final -- there's no 'Oops' button!
Track start time can, however, be freely adjusted without cropping. This simply sets the track start time relative to the start of the playlist, so if you want a track to start a couple of seconds later, you just add two seconds to its current value using the cursor buttons. You can't make the start of a track earlier than the end of the previous track, though -- overlaps or crossfades are not supported. This software version also isn't geared up for the kind of cut, copy and paste editing you'd need to rearrange material within a track, or the ability to vary levels within a track, as found in some software mastering packages.
Having been used to a computer editing system, I expected the MasterLink to be awkward and fiddly, but that wasn't the case. The single-function buttons and the easy menu structure, combined with a mercifully brief manual, actually make it very easy to use, and within my first hour, I'd put together an album of tracks I'd been working on. I then went for a coffee while I waited for my CD to cook! The one-hour album with DSP processing rendered in around 20 minutes and burned in a further 20 minutes, playing back perfectly on completion. I found the fade-in/out quality smooth and the recording quality is as good as it gets without going to super-high-quality stand-alone converters that cost a lot more than the entire MasterLink does! I also found the built-in EQ to be very effective for mastering work, as it doesn't alter the overall tonality of the music too much, it simply adjusts the harmonic balance.
Alesis have done a great job with MasterLink and any criticisms have to be balanced against the fact that this box costs little more than some stand-alone CD recorders. Perhaps they should have included a simple, direct CD burning mode for those with ready-edited DAT tapes or for backing up existing CDs, and a QWERTY keyboard input might have made some of the operations easier, but you can't have everything you want as well as a low price.
Of course, it's important to know what MasterLink can and can't do. It can help you burn a CD from previously mastered tracks and it has good onboard EQ and dynamics processing to help you with this, but you can't rearrange sections or vary levels within songs; both functional areas where software-based mastering packages still have the edge over MasterLink. I also fail to see why there's no Undo facility, nor any sort of non-destructive track length-tweaking facility to allow songs to be constructed from segments more easily; but then this is still only version 1.00 of the software. Apparently some cut-and-paste editing options are planned for v2 later in the year.
These limitations aside, MasterLink is a well-thought-out tool that offers all the key facilities needed to make a bunch of mixes sit happily together on the same album. The ability to record and archive 24/96 recordings should also not be underestimated as you could conceivably mix directly onto the MasterLink, then save your mixes in CD24 format. In this respect, it's an effective archiving solution for studios, broadcast, or even DJs.
In summary, whether the Masterlink is right for you depends mainly on the level of editing you expect to be able to achieve and on whether or not you already have a computer. I have to admit that I find my Mac editing software rather more powerful for doing surgery on tracks, and Adaptec's Jam is hard to beat for rapid album assembly, but if you don't want to go the computer-based route, then MasterLink provides an easy way to assemble finished tracks into an album format and to burn them onto a Red Book CD. Furthermore, although there are only four DSP effects, they're the ones you're most likely to need to use when mastering, so you don't need to spend more on plug-ins. It's hard to believe this is version 1.00 of the software, as MasterLink seems stable, has no operational foibles I'm aware of, and produces fine-sounding results.