Fostex D2424

Derek Johnson & Debbie Poyser test Fostex's new hard disk 24‑track. The D2424 may not have quite the feature set of its two main rivals, but the facilities it does have may be very well targeted towards the intended users.

Something that quite often happens in the world of hi‑tech music recording is that several manufacturers working on a new and (we always hope) exciting development cross the finish line almost together. So, where we had hardly any choice at all in a given sector, we suddenly get three or four — which theoretically is great, but in practice can mean quite a lot of head‑scratching. As Devo said so eloquently, "Freedom of choice is what you've got / Freedom from choice is what you want".

And it's happened again with affordable stand‑alone hard disk 24‑tracks. We'd been wondering for a long while what had been keeping them, when stand‑alone 16‑tracks seem to have been around for ages, and now, sure enough, three have turned up since August of last year. Tascam made it first, with their MX2424 (reviewed in SOS August 2000) and Mackie followed close behind with the HDR24/96 (reviewed SOS October 2000). And now there's Fostex's D2424, which is really a double breakthrough, in that it offers not only 24 tracks, but also the 24‑bit, 96kHz recording that seems to be preoccupying the market at the moment.

At the outset, it's probably just as well to say that, happily, even though these three machines seem to offer similar basic powers, they'll probably be easy to choose between. Their respective ideal users should be able to look at what each offers and feel instinctively which they should go for. SOS editor Paul White, who reviewed both the Mackie and the Tascam machines, felt quite strongly that we might see a fairly tidy split, with the Mackie going to more serious music recording and project studios, and the Tascam finding its way into professional broadcast and post‑production environments. The D2424 brings a couple of extras to the party that, for many, will set it aside from the other two: firstly, it's a more straightforward replacement for a 24‑track tape machine than either of its competitors, which offer significant visual editing powers, and, secondly, it's a lot cheaper because it doesn't have all their bells and whistles.

Facts & Figures

Unlike its direct competitors, the Fostex D2424 comes with a wealth of analogue and digital I/O as standard — eight analogue inputs, 24 analogue outputs and 24 channels of ADAT digital I/O, as well as MIDI, word clock, RS422 and SCSI connectors.

The D2424 belongs very much to the constantly evolving Fostex hard disk recorder family, and is a logical development of their stand‑alone eight‑track and 16‑track machines. It's almost identical in appearance to the new D1624 (see the 'Keep It In The Family' box), except that the 16‑track has a charcoal‑grey case and detachable cream front panel, while the D2424 is finished entirely in charcoal grey. The front panel is still detachable, though (it would hardly be a Fostex if it wasn't!), and forms a neat remote control which necessarily duplicates all the D2424's front‑panel controls, because it is the front panel. This is one of the keys to the D2424's lower total price when compared to the Mackie and Tascam machines: you don't have to budget extra (anywhere between £250 and £1155 in the case of the aforementioned two) for a remote. You might have to budget for a 10‑metre extension cable, though (at around £35), as you can't get very 'remote' with the supplied five‑inch one. The D2424 also features an RS422 port to support the Sony nine‑pin protocol for compatibility with standard pro video and digital video workstation remote controls.

The second reason why the Fostex works out rather more cost‑effective is found on its back panel: quite a lot of I/O as standard, right out of the box. To be specific, you get eight analogue inputs and 24 analogue outputs, on balanced jacks (which can be switched for unbalanced operation, if desired), plus 24 channels of ADAT I/O on three optical connectors. These can also operate as stereo S/PDIF in and three pairs of stereo S/PDIF outs. This supplied audio I/O starkly contrasts with the Mackie and Tascam machines, which come with little or none, instead requiring you to purchase what you need on optional cards. The Fostex has optional extras too, of course, mainly geared towards those with specific applications in mind (see the 'Optional Boards' box for details).

To give a basic idea of its capabilities and features, the D2424 is a 2U, rackmounting 24‑track which records uncompressed digital audio to a supplied internal 15Gb IDE drive. A second drive bay can accommodate another hard disk, or a DVD‑RAM option, and there's also SCSI as standard. However, you can only back up to these supplementary drives, rather than being able to record direct to them. The comprehensive array of backup options is completed by DAT and ADAT methods.

Alongside its 24 playback tracks, the D2424 has 32 virtual tracks — one area in which it really doesn't match up to the Tascam or the Mackie, which offer loads more. It provides a total of six recording formats: 24‑bit/96kHz, 24‑bit/88.2kHz, 24‑bit/48kHz, 24‑bit/44.1kHz, 16‑bit/48kHz and 16‑bit/44.1kHz. Four things happen if the 96kHz or 88.2kHz options are used: recordable tracks are cut to eight; virtual tracks are increased to 48 (the total number of available tracks in all cases remaining at 56); DAT and ADAT backup become unavailable; and the ADAT ports become inoperative — understandably, because the ADAT format doesn't currently support audio at sample rates above 48kHz. Recorded audio can be edited directly from the front panel, with the help of the large fluorescent display, and though the operations available are quite basic, they certainly allow tracks to be chopped about and reassembled in a different order, with bits repeated if required. If more detailed editing is needed, tracks can be exported as WAV files via a fixed or removable drive attached to the SCSI port, or transferred out of the ADAT ports to an ADAT‑equipped soundcard, say, for computer editing with a favoured software package.

The D2424 benefits from the latest version of the Fostex Disk Management System, FDMS3. This should be familiar to anyone who's used a Fostex digital machine, even one of the all‑in‑one multitrackers. Desirable added features include unlimited undos (dependent on disk space), a big improvement over Fostex's previous less‑than‑generous one level of undo; copying and pasting of material between songs (Hallelujah!); better video sync capabilities (with an optional board set); and Program Chain Play, which allows you to automate sequential playback of a number of Songs, presumably for on‑stage use.

Up & Running

All functions of the D2424 are accessible from the controls on its detachable front panel, and the associated display shows the level meters, along with the current time position and other information.

When it ships, the D2424 has no hard drive fitted. However, there is one in the box with it, and this must be installed into a 'ruggedised' caddy that fits into a drawer behind the front panel. Extra caddies cost about £40 each, and with hard drives now so cheap it may be a viable proposition to fill them up one at a time, archiving them as you go.

The drive must be formatted to the desired recording mode. Unfortunately, once a drive has been formatted for a particular mode, say 16‑bit/44.1kHz, all Programs (songs) on that drive have to be at that bit depth and sampling rate. Unlike the flexibility of, say, the Tascam MX2424, the D2424 doesn't allow 16‑bit and 24‑bit recordings to be mixed on the same drive, let alone within the same Program. At this time you can also choose between one level of undo and unlimited undos. It's nice to discover that Fostex now provide a drive optimisation routine, possibly because unlimited undos could lead to rapid fragmentation of the disk.

The next step depends on what kind of mixer is being used with the D2424. If it's analogue, it's just a matter of hooking up the desk's eight subgroup outputs to the D2424's analogue ins, and the D2424's analogue outs to 24 mixer channels. If you're wondering how you can record to 24 hard disk tracks with only eight inputs, each input is hard wired to three disk tracks: input 1, for example, feeds disk tracks 1, 9 and 17. This begs the question of how you could record different audio to tracks 1 and 9, say, at the same time. Basically, you can't when using these analogue inputs — but you can use the Track Exchange feature to move audio about to the tracks of your choice once it's recorded. Anyone who's desperate to record more than eight analogue tracks at once could invest in Fostex's AC2496 option, which attaches to an ADAT port and provides eight more balanced inputs. All 24 tracks can be recorded at once via the ADAT inputs, however, providing your desk can output audio on three sets of ADAT output connectors.

There are a few things to consider if the D2424 is to be used with a digital mixer. First, can the mixer handle 24 tracks of digital audio coming from the recorder on mixdown? There are a number of desks that are compatible with 24 tracks of ADAT‑format digital audio, though all of these need some form of optional card or external adaptor box. Mackie's D8b, Yamaha's 02R, Tascam's TMD4000 and TMD8000, Roland's 7000‑series V‑Mixers, Sony's DMX R100 and the Ramsa WR‑DA7 all fall into this group. If the desk in question can't do it (like the lower‑cost Yamaha digital desks, for example), it would be necessary to send the audio out through a mixture of digital outputs and analogue outputs (going through a D‑A conversion in the latter case). The by‑now analogue tracks would then go into the desk via its analogue ins, passing through an A‑D conversion. Not quite in keeping with the all‑digital dream, though you probably wouldn't hear any difference. (In fact, it's quite a common thing to find pros replacing analogue recorders with digital multitracks but keeping, or upgrading, their analogue consoles.) Assuming the desk can accommodate the D2424's digital connectivity, there are some digital interfacing and clocking jobs to do. Ideally, the D2424 would be the digital clock master and, in some cases, setting the target desk to be a 'slave' to its ADAT inputs might be sufficient; if the desk is equipped with a word clock input, however, the D2424's word clock output would be connected to this.

Record & Play

With the Fostex D2424 there is no need for a separate remote controller — an optional 10‑metre extension cable allows you the flexibility to widely separate the main rack unit and the detachable control surface.

Basic recording with the D2424, as with other Fostex multitracks, is essentially very tape‑like: record‑enable the desired disk track (using the enable buttons under the display), then press the Record button to audition whatever's being recorded. There are only eight record‑enable buttons, but these are shifted into three groups to account for all 24 tracks.

Metering is provided by the display, as the D2424 doesn't have dedicated hardware metering like the Tascam and Mackie machines. However, the metering provided is clear and accurate, with the peak‑reading bargraphs showing green until the audio level hits 0dB, when they turn red to indicate that clipping is about to occur. There's no user control over peak hold, but it seems to hold for long enough anyway. While we're on the subject of metering, the fact that the Fostex remote is the front panel means that full metering will always be in view, even if the user and remote are situated quite some distance from the machine. This isn't guaranteed with the Tascam MX2424 remote (whose only metering is clip LEDs) or the Mackie HDR24/96 at the time of its review, when the only remote available had just one meter switchable to reflect its 24 tracks one at a time. A bigger remote was planned, though, and metering for the Mackie is duplicated on any connected monitor.

The D2424's built‑in metronome derives its tempo from the onboard tempo track, of which more in a moment. As with other Fostex digital recorders, using the metronome takes up one track, which can't be recorded to or monitored while the metronome is on; in this case, it's track 24. If there is audio on this track, you don't lose it by turning on the metronome; it's just not accessible while the metronome is in use. When the 24‑bit/96kHz recording mode is being used (which, as we've said, reduces the track count to eight), the metronome is still output from track 24, so track count is never compromised in this mode.

With levels and metronome (if required) set, pressing the Record and Play buttons together initiates recording, and if the take is unsatisfactory the dedicated Undo button consigns it to history. Punching in and out can be done manually (with front‑panel controls), via footswitch, or can be pre‑programmed, producing excellent results with no pops or clicks. It's possible to set punch‑in/out points very precisely and when you've established a personal procedure this is very fast too. There's no facility for multiple punches in one pass, though.

The nice Jog/Shuttle wheel helps during track navigation, with the inner Jog part performing audio scrubbing in both directions, while comprehensive fast‑wind options are accessed with the outer, sprung Shuttle collar. The other functions of the Jog/Shuttle wheel are parameter selection and value changing.

As you'd expect, it's possible to set more locate points per Song than you would reasonably need — up to 99 — though if your requirements are modest, the six 'Edit Memory' buttons (used to set punch in/out points, edit points and so on) can be used for quick auto‑location; and, of course, you can locate to the beginning of a Song by pressing Stop plus Rewind, or to the end by pressing Stop plus Fast Forward, just like on every other Fostex digital multitrack. If locate points have been set in a haphazard way, and their position in the numbered locate memories doesn't correspond with their correct chronological place in the Song, there's even a Direct Locate function that sorts the locate memories into chronological order. Finding the next one is then just a matter of using the front‑panel Prev and Next keys.

There are few complaints to make about the D2424 recording process, which is easy and quite intuitive, though the new colour scheme is perhaps not as conducive to comprehension as that of previous Fostex digital machines — mostly charcoal‑ grey buttons on a charcoal‑grey background, with small legends. The button layout is still slightly disorganised, too, so initially you do poke about trying to find things. Still, it's nothing to make a big deal about.

Hack & Slash

Tracks are armed for recording using an assignable bank of eight buttons which can be allocated to tracks 1‑8, 9‑16, or 17‑24 by using the Track Shift button.

One area in which the D2424 stands out as being radically simpler than the Tascam and Mackie competition is digital editing. By 'simpler', we mean not only that its editing facilities are easy to use (which they are), but also that they are fewer and less sophisticated. Tascam and Mackie have both gone out of their way to compete with DAWs (Digital Audio Workstations), offering the ability to connect a computer running dedicated visual editing software in the case of the Tascam, and the ability to directly plug in a monitor, keyboard and mouse with the Mackie. As the Mackie is practically a full‑blown PC anyway, you can imagine how impressive its visual user interface is. Both machines provide something akin to the computer recording experience, though they don't go as far as something like Pro Tools.

By contrast, Fostex's hard disk editing is more like a digital razor blade, but for a great many people this will be quite sufficient. If what you're after is really an analogue tape machine replacement, you might not need it to be able to give you a display like a computer sequencer. The editing features Fostex do provide offer more flexibility than any analogue machine, but they don't try to compete with dedicated audio sequencers. Many Fostex users apparently do run their disk recorders sync'ed to computer sequencers, and for these people it should be relatively easy to swap audio between multitrack machine and computer‑based software editor (see the 'Computer Love' box).

So what can be done? Audio can be Erased and its space returned to the general pool, Moved And Pasted, or Copied And Pasted, to another point in the song or — new for FDMS3 v3 — even to another song (the last is great news!). It might also make the virtual track limit easier to live with, as an entire other song could provide an auxiliary store for alternate takes. Audio sections can be automatically pasted up to 99 times, making song extensions easy. Multiple Erase operations are possible too. We've lost count of how many times we've moaned about the fact that Fostex machines can't insert a section of audio, pushing subsequent audio along to

make space, and this ability still isn't present, even after the recent FDMS update — are we really the only people asking for it?! By the way, editing is not 'playlist' style, but uses up actual disk space with every new copy.

Searching for an edit point is facilitated by the fact that the bar‑graph meters in the display can turn into a strange but useful representation of a waveform that you scroll through using the Jog wheel. Audio feedback is available at the same time, its speed dictated by how fast the Jog wheel is twirled. This makes it easy to home in on the right spot.

The last 'editing' feature to mention is Track Exchange, which is used to move all the audio on one playback track to another playback track, and also to swap virtual tracks with playback tracks. This operation is easier because tracks can now have names of up to eight characters.

"Even though the D2424 may not provide as feature‑filled a hard disk 24‑track as its competitors, the bottom line is that it does the job, in an uncomplicated, efficient, economical and reliable way."

MIDI & Sync

Out of the box, the D2424's MIDI spec is identical to other Fostex multitracks. It can generate MIDI Clock, for sync'ing simple MIDI sequencers and drum machines, and can respond to and generate MIDI Time Code, with the same range of frame rates as offered with the optional 8345 video sync board set: 24, 25, 29 and 30 frames per second, with 29 and 30 drop‑frame options. MIDI Machine Control is also implemented for remote transport control of or by the D2424.

Common to all Fostex digital multitracks are the tempo and time‑signature maps, both essential when sync'ing MIDI gear to the D2424. Creating tempo and time‑signature maps (each has 64 steps) that match a slaved MIDI sequence allows the user to edit D2424 audio with the same precision and ease as the MIDI data. While the D2424 doesn't have the useful ability of the Mackie HDR24/96 to import tempo and time‑signature data from a MIDI file via a floppy drive, the Fostex system is straightforward: just choose the bar and beat location that requires a tempo or time signature change, and insert it. When selecting time signatures, the choices range from 1/4 to 5/4 and from 1/8 to 8/8, which is quite adequate for most purposes. However, though the occasional 7/4 or 10/8 bar can be created out of two consecutive changes, it would be tricky to keep it going for an entire song — trying to set up a 7/4 time signature by alternating 3/4 and 4/4 signatures would use up the 64 steps within 32 bars!

Further sync facilities are supplied by the optional 8345 timecode/sync board set, for compatibility with SMPTE/EBU‑savvy devices.

Sound & Noise

The ADAT optical I/O and word clock connections are standard on the D2424, and allow it to connect into professional all‑digital setups

The D2424 is reasonably quiet in terms of the ambient noise it generates. It shouldn't drive you mad with annoying high‑pitched whining, as some digital recorders do. However, you wouldn't want to do sensitive acoustic recordings right next to it, because of the rhythmic disk 'burping', sometimes fairly loud, that it can emit when in record mode, especially when recording 24 tracks at once.

Actual D2424 recordings are wonderfully noise‑free, clean and punchy, as you would expect, with 24‑bit/96kHz mode sounding especially pleasing. We happened to have the new D1624 around at the same time as the D2424, so we were able to record the same acoustic guitar/vocals/bass song twice, at 16‑bit/44.1kHz on the D1624 and at 24‑bit/96kHz on the D2424 (note that the D1624 also does 24/96 recording). One of us then turned our back while the other one switched between the two, and we found that we could hear a bit more detail and presence in the 24/96 audio — though there was nothing at all wrong with the lower bit depth and sample rate recording.

Over & Out

Fostex just keep going in the same reliable way, producing digital recorders that stick with the same type of OS, so long‑term users can upgrade in the confidence that the change‑over will be smooth and painless. Their machines function with the minimum of fuss, don't overload the user with possibilities, and are remarkably stable and robust, from what we've seen over the years. Stated features all tend to work right out of the box, too — unlike its competitors, the D2424's 96kHz recording is available as soon as you get the machine, even though it can only manage eight tracks at this rate, compared to the promised 12.

It's business as usual for Fostex as far as the D2424 is concerned, since they've approached it in exactly the same way as their eight‑tracks and 16‑tracks — no bad thing for the end user. Mackie and Tascam have gone to town with what digital can do, and if their large, professional feature sets and visual editing capabilities are best for your application and way of working, you'll know it. There's no knocking the usefulness of seeing everything on a big screen, after all. On the other hand, if you just want a 24‑track hard disk recorder that works like a tape machine (but with a range of useful extras), that sounds great, and that gives you the option to work at high sample rates and bit depths, have a serious look at the D2424. From a financial point of view, the generous built‑in I/O and 'free' remote are very welcome, and even if you added all the optional extras it would be hard to get the D2424's cost up to the level of its competitors: they both start with higher prices and then need most or all of their I/O — plus a remote if required, and either a computer or a monitor, mouse and keyboard for the editing — to be paid for on top.

The negatives we'd identify about the D2424 are the limited number of virtual tracks, the fact that the display still doesn't have high enough resolution to properly display waveforms, and that the editing is not as powerful as that available on the Tascam and Mackie machines. It also might be inconvenient for film and video types that the video sync board has to be bought as an option.

However, even though the D2424 may not provide as feature‑filled a hard disk 24‑track as its competitors, the bottom line is that it does the job, in an uncomplicated, efficient, economical and reliable way. Let's not forget that the Chinese curse their enemies with the words: "May you live in exciting times!"

Computer Love

Obviously, the D2424 doesn't have the built‑in ability of its 24‑track competitors to plug into a computer or monitor for direct 'online' audio editing, but it is very well set up for offloading audio into a computer for editing there. The simplest method is to transfer tracks directly to the computer as WAV‑format files, using DOS‑formatted media. This requires either that both the D2424 and your computer have access to the same type of removable media, or that you have an external fixed SCSI hard drive that can be dedicated to transferring audio. Remember, though, that when using a fixed SCSI drive, the D2424 and computer need to be shut down before connecting or disconnecting it. The process is quite straightforward, and is aided by the fact that Fostex audio tracks can now be named.

The second audio transfer technique is available to anyone with a PCI audio card‑ equipped computer, as long as the card has S/PDIF or ADAT‑format optical connectors. D2424 audio can be piped two or eight tracks at a time to any compatible audio application. Rather than streaming the audio directly to a sample editor, it's best to first import the audio into a MIDI + Audio sequencer, so that it'll be possible to maintain some form of sync when moving the audio back to the D2424. Most digital audio cards aren't equipped with sophisticated digital sync options, so the user is reliant on the sync information inherent in the S/PDIF or ADAT stream, and MTC for locking the target sequencer and D2424 together. This is necessary in order to maintain actual track length, so that the audio, once tweaked on the computer, can be precisely replaced in its original track. It also helps if you don't cut any audio from the beginning of a file. We have, with a little practice, successfully moved audio back and forth between a Fostex digital recorder and Pro Tools LE software on an Apple G4, via Digidesign's Digi 001 hardware. The combination of PCI card‑equipped computer and D2424 might work better for some people than doing all audio recording on a computer, leaving the computer to handle just MIDI, rather than audio, sequencing.

Fostex in the USA, seeing the computer‑like capabilities of the D2424's competition, have assembled a bundle that includes the multitrack, a Mac/PC‑compatible RME Hammerfall PCI card (which offers 24 channels of 24‑bit digital I/O) and C‑Mexx's C‑Console software. The latter is sadly PC only, but aims to provide full remote access to the D2424's transport (via MMC), metering, settings and more. The TCP/IP plug‑in adds remote control over a network (including the Internet) and there's a speech plug‑in that's an ideal option for blind and handicapped users, or for anyone requiring hands‑free operation. Versions will also be released for the D1624 and D824. While it's unlikely that UK Fostex distributor SCV will release an identical bundle, D2424 users can come up with something similar under their own steam if they like. Watch the SOS news pages for any activity regarding the C‑Console software.