Superficially, it may look no different from other soundcards, but Yamaha's new DSP Factory is a real TARDIS when it comes to facilities. Martin Walker explores a soundcard that's bigger on the inside than it is on the outside.
If you were offered a brand new soundcard for under £600, which not only provided hard disk recording facilities but also contained the inner functions of a Yamaha 02R digital mixer, you might suspect that it had fallen off the back of a lorry. But there's nothing shady about the DS2416 digital mixing card, which will be available from all Yamaha dealers by the time you read this. The DS2416 forms the heart of Yamaha's DSP Factory hard disk recording system, and is a PCI soundcard which supports up to 24 channels of digital mixing and 16 simultaneous channels of audio playback from a hard drive.
The secret of the DSP Factory's amazing price is that while it provides onboard DSP (Digital Signal Processing) functions that will make many people's jaws drop, the I/O on the basic soundcard has been kept to a sensible minimum. On the backplate of the card, therefore, there are just six phono sockets — In L and R (analogue), Out L and R (analogue), Digital In, and Digital Out — although the system can be expanded to provide more external inputs and outputs if required (more on the expansion options in a moment).
By now, however, you may be slightly confused: what's the point of having 24 channels internally if there are so few hardware ins and outs? The secret is in the 02R mixer functions provided by the DS2416's onboard DSP chips. If you are using the DS2416 by itself, you can record mono or stereo audio channels separately to your hard disk at up to 32‑bit resolution (depending on the software you use). When it comes to playback, however, up to 16 channels of audio can be streamed from your hard drive simultaneously, each with its own internal mixing channel which provides a four‑band parametric EQ, dynamics processor, six aux sends, 10 buss outputs, and comprehensive metering. There are also two on‑board stereo multi‑effect units (based on the Yamaha REV500), and these provide a choice of 12 reverb types, 11 modulation types, two distortions, three dynamics processors, and 12 combination effects.
The DS2416 is also free of the limitations faced by some other systems where resources must be shared between the channels — you will never have to decide whether to remove some EQ from existing mixer channels to release enough DSP power to add compression to another, for instance. The DS2416 can simultaneously run a total of 26 channels (by default these are mapped as the 16 hard disk audio channels, four effect returns, two external analogue inputs, two external digital inputs, and a stereo master output channel), 104 bands of parametric EQ (four bands for each channel), and 26 dynamics processors.
All of this, moreover, is accomplished without using up any of your computer's CPU processing power at all, since the processing is all done by the soundcard's DSP chips. Given the number of people struggling to run a small selection of real‑time plug‑ins with their chosen MIDI + Audio sequencers, DSP hardware effects support is more than welcome. Although most modern soundcards have at least one DSP chip which normally controls audio mixing and routing, and several manufacturers have promised future updates with some of their spare DSP power devoted to proprietary effects, it is much safer to rely on a system that ships with this built in from the start.
Expanding Your Horizons
Although the DS4216 is a standard PCI expansion card, it is only seven inches long, and should therefore fit into nearly all PCs or Macs. Little touches of quality abound, such as the black anodised finish of its backplate, complete with gold‑plated phono sockets. The analogue inputs and outputs both feature 20‑bit converters, and the S/PDIF input and output will operate at up to 24‑bit resolution. If you only tend to record your music a track at a time, this basic I/O will probably be enough, but four additional internal connectors are provided along the top edge of the circuit board for expansion purposes.
The IO‑A and IO‑B connectors let you add one or two optional AX44 expansion units. Each provides an extra four analogue ins and outs using unbalanced quarter‑inch jack sockets, as well as a headphone output, attaches to the DS2416 by an internal ribbon cable, and is fitted into a spare 5.25‑inch drive bay on the front of a PC (see box for further details). The audio streaming engine supports up to eight simultaneous recording channels, and with a full complement of a DS2416 and two AX44s, you will have a total of 10 analogue inputs and 10 analogue outputs, as well as the digital in/out. An 16‑channel ADAT‑style optical interface has also been mentioned for future release (both the IO‑A and IO‑B connectors can accommodate either four‑ or eight‑channel expansion units).
The other two internal connectors are Serial In and Serial Out, which allow either a further DS2416 card to be cascaded for 48‑channel operation, or the integration of the forthcoming SW1000XG card. This adds a 64‑voice polyphonic MIDI synthesizer, complete with 20Mb of ROM waveforms from the MU100 MIDI module, and a further five multi‑effects processors. The SW1000XG should run in perfect sync with the DS2416, with the former's MIDI voices having access to all of the latter's 02R mixing and effect functions.
Installation
The DS2416 requires a single IRQ and no DMA, and since PCI cards have their IRQ settings chosen automatically, installation is simple. Once the new hardware has been recognised by Plug and Play, Windows requests the supplied floppy disk containing the Multimedia driver files, and you should be up and running in only a few minutes.
The drivers appear to Windows as eight stereo output pairs (DS2416 #1 to #8 Wave Outs), and four stereo input pairs (DS2416 #1 to #4 Wave Ins). Mac drivers, as well as ASIO drivers for Cubase VST, are both promised in about October.
Because of the Multimedia drivers, the DSP Factory should immediately work at the basic recording/playback level with any Windows 95 or 98 audio application, which means that anyone already using packages such as Logic Audio, Cubase VST, Cakewalk Pro Audio, or one of the stereo sound editors like Sound Forge or Wavelab, will be able to get useful work done straight away, without having to learn a new recording package.
There is little to see once the drivers have been installed — when you run the Setup.exe file (also on the driver floppy disk) a small Check utility is installed which reports on how many DS2416 cards have been found and whether the drivers have been installed properly, and checks for correct functioning of the onboard DSP chips. A 1kHz sine wave test tone can also be sent through all analogue and digital outputs, including any connected AX44 expansion unit outputs, which is useful when checking your external wiring.
On the accompanying CD‑ROM (along with the PDF version of the supplied printed manual and various demos), a separate Patch.exe utility is also provided. This provides basic input/output patching, word clock source and digital I/O format selection, if you don't have an audio application that directly supports the DSP Factory (see the lower screenshot on page 184).
Software Support
The DSP Factory is primarily a hardware product, and Yamaha are relying on third‑party developers to add support for it in new or existing software. Given the exciting nature of this product, there is no shortage of companies who are adding the required low‑level calls to the Yamaha hardware so that their software can talk to it directly. It is up to the individual developers to decide how these extra facilities are marketed — some may provide free updates downloadable from a web site, others may introduce them in a chargeable upgrade, and there are some completely new products as well.
At the time that this review was written (late August), much of this software was still in beta form, but even so there were various applications being demonstrated at the Yamaha press launch, some of which I was allowed to take away. By the time you read this, more of these applications should have been launched.
Cakewalk have been quick off the mark — there is already a free update (DSPFactory.exe) available on its web site for Cakewalk Pro Audio 7, which installs and registers the various audio effects plug‑ins that are supported by the DSP Factory. All the MIDI and audio channels appear in the Console view (see screenshot on page 181), and the right‑hand side of this shows the eight new DSP Factory stereo track pairs (the Master sections). By right‑clicking the patch‑point in any Master section module, you can patch in any DirectX or DSP Factory function. DirectX Insert effects can be used both as track inserts and in aux busses, but the DSP Factory FX can only be used as master effects.
In essence, you can use DirectX plug‑ins (if required) on individual audio channels, and then route any number of these channels to any of the eight stereo pairs of DSP Factory channels for further EQ, dynamic or effect processing. This allows more than 16 channels of audio to be played back and mixed simultaneously. Controls to edit individual channel EQ, Dynamics and Effects appear on demand in separate floating windows, which keeps the main display comparatively uncluttered. Cakewalk also seem to have cleverly re‑engineered the DSP Factory effects as DirectX compatible plug‑ins — after installing the Cakewalk update I found three extra entries for the Equaliser, Dynamics, and dual Multi‑effects in my other DirectX compatible applications, with identical Cakewalk windows.
I was lucky enough to be authorised to try out a beta version of the forthcoming Cubase Audio VST/24 version 3.6, which also has specific DSP Factory support. This is an upgrade to Cubase Audio VST (and not the standard VST and Score versions). It wouldn't be fair to comment on any of the other new features of this software here, since it wasn't a completed version, and some things may well have changed before the release date. However, there were three completely new windows specific to the DSP Factory, controlling the Mixer, twin Effects processors, and the bus/Aux outputs (see screenshot above). Steinberg have implemented the mixer with mono channels (rather than the stereo ones of Cakewalk), so each has its own pan control. Although this seems more v ersatile, you currently have to set up alternate channels in the VST mixer as bus 1 left, bus 1 right, bus 2 left, and so on, so that they are routed correctly to the DSP Factory mixer.
The VST mixer graphics look wonderful, and to cope with the huge number of extra controls, various display options are available — these are switched by clicking on the narrow strip running horizontally across the mixer above the faders. The 'Narrow' option shows only Pan, Fader, Meter, and Mute and Solo buttons at the bottom of the channel strip, whereas the EQ, Dynamics, bus Send, and Aux Send options each expand the channel to double the 'Narrow' width, and provide the appropriate controls for each of these functions in the area above the fader section.
The new DSP Factory Mixer console can be used alongside the existing VST mixer console, to provide access to both hardware effects and software‑based effect plug‑ins, and every one of the hundreds of new DS4216 controls can be fully automated. Since the twin effects of the DS2416 are more easily used for providing more global effects such as reverb, I found myself using the VST Channel Inserts for specific DirectX plug‑in effects to supplement those of the DSP Factory. My main reservation here is that to access both ActiveMovie and DSP Factory effects, you currently need to run both mixers (VST and DSP Factory) side by side, which not only takes a bit of getting your head around, but also needs a large monitor to fit everything on screen at once. However, these are early days, and by the release date there may be more integration.
Emagic's Logic Audio Gold and Platinum are also being provided with DSP Factory support, and these are again up to the beta stage, although I didn't manage to try the new facilities for myself. The update will be free to registered users, with release expected by the end of September. However, Emagic's approach seems to be a combination of those taken by Cakewalk and Steinberg. Each of the 16 Tracks can use up to six Inserts (any combination of DirectX plug‑ins or the Yamaha EQ or Dynamics), as well as two Effect Sends to the DSP Factory multi‑effects. Control of the two effects and the stereo Master channel is on the right‑hand side of the mixer.
The advantage of this approach is that you only have to deal with a single integrated mixer, and each of the 16 channels can have its own Pan (or Balance) control. However, without any further submixing facilities, there will be a maximum number of 16 channels available for audio use. Logic Audio uses the Yamaha multimedia driver for playback and recording, and therefore their PC AV driver (for other MME soundcards) cannot be used simultaneously with the DS2416, although (as is often the case with Emagic) parallel operation with Audiowerk8 is still possible. At this stage, it's not clear whether Logic will offer support for multiple cards, or just one.
If your favourite hard disk recording package doesn't provide direct support for the DSP Factory system, there are also stand‑alone programs which you can run alongside it. C‑Mexx have already produced several pieces of software which provide remote control and a computer front end for other Yamaha digital mixers such as the 02R and 03D. Their C‑Console provides a more traditional mixer view for the DSP Factory (see top screen above), which may suit some people better than the other virtual interfaces. It has snapshot facilities, as well as providing libraries for functions such as EQ and Effects, and if you are running it alongside SEKD's Samplitude package, up to six parameters on each channel can be chosen for automation. However, while well designed and graphically easy to use, at £149 (including VAT) it is an expensive way to gain access to functions that other sequencer manufacturers are providing as free updates or for a modest upgrade fee.
In Use
I was able to spend some time using most of the applications listed above, and was very impressed with the DSP Factory's audio performance — as you might expect, considering the excellent SOS reviews already received by the 02R and 03D digital mixers (August '95 and June '97 issues respectively) and the REV500 reverb (March '97 issue). Audio sound quality was excellent, and although all of the packages I used were currently only capable of 16‑bit operation, background noise was still very low. Using my standard Sound Forge test for A/D conversion, I measured signal/noise ratio at 90dB, which would equate to about 93dB when A‑weighted (exactly what the manual claims).
I was particularly interested in comparing the effects to other DirectX plug‑ins at my disposal. There are 39 algorithms for Effect 1, and 40 for Effect 2 (the extra algorithm provides "High Quality Pitch Shift"). These range from various reverbs, early reflections and gates, through echoes and delays, chorus, flange, and phaser, t o more unusual options such as ring mod, an amp simulator, dynamic filter, and various combinations of effects such as distortion and delay. These are all up to Yamaha's normal high standards, with clean smooth reverb tails and low noise (although, as you might expect, you do have to be careful with the distortion options where unwanted noise is concerned).
Yamaha's reverbs, in particular, sounded very smooth when compared to a variety of DirectX plug‑ins (including Waves' TrueVerb, the Hyperprism Hyperverb, and the TC Native Reverb), and I suspect this may be due to having the luxury of more processing power allocated from the DSP chips than anyone could afford to give to a DirectX plug‑in. All of these reverbs sound good, and I would happily use any of them in a track, but of course the beauty of the DSP Factory effects is that switching them in gave absolutely no increase in the computer's CPU overhead — it almost seemed too good to be true.
Conclusions
Many people need to record only a single mono or stereo track at a time, but still want multitrack outputs to patch in external effects (largely because you normally need such a powerful computer to run many effects in software). The beauty of the DS4216 is that with high‑quality integral effects (which take no processor overhead from your main computer CPU at all), the requirement for multiple outputs becomes less important. The onboard DSP mixing power may also enable your computer to manage a larger maximum number of simultaneous audio channels.
In case you do decide that you want more access to the outside world, however, buying an AX44 in addition will give you a total of six analogue ins and outs for a total outlay of just under £800. £1000 will get you a DS4216 with two AX44 units, giving 10 ins and outs (not to mention the stereo S/PDIF digital I/O). You can even cascade a second DS2416, giving a potential 48 mixer input channels. The DSP Factory looks destined to appear on many musicians' shortlists. It sounds good, and provides an incredible amount of hardware capability on a single soundcard.
My main reservation is in the area of the user interface. Although you can use the DS2416 immediately with any Windows 95/98 application for recording and playback, access to the mixer functions relies on third‑party software support. Whilst developers are beavering away adding facilities to existing software, each of them is accessing the hardware features in a different way. At the time of writing, Logic Audio seems to have the most elegant implementation (at the expense of having a maximum of only 16 audio channels, and no confirmed support yet for an additional DS2416). Cakewalk takes the straightforward option of effectively letting the DS2416 provide eight additional stereo subgroups to its previous maximum of 64 audio tracks. Cubase VST provides the most ambitious interface, and you can quickly create a huge virtual mixer alongside the existing VST one. This, however, can rapidly get unwieldy, especially when inserts have to be set up on one mixer and DSP Factory effects on the other, although things may well have changed by the time of the release version. There are currently no options for a hardware control surface, which would make day‑to‑day operation a lot easier. Given that every implementation of software is different, however, additional hardware support may be unlikely to appear.
Yamaha are to be firmly congratulated on their hardware achievement. When I first mentioned the DSP Factory way back in the March '98 PC Notes, the only mention of likely price was 'under £1000'. Now that it has arrived, with a shipping price of £599 (including VAT), it represents remarkable value for money. The DSP Factory blows most of the competition out of the water in terms of facilities, but whether or not you find these facilities easy to use will depend largely on your choice of software.
Audio Specification
DSP FACTORY SYSTEM
Sampling rates: 44.1kHz or 48kHz internal, 41.45kHz to 50.88kHz internal varipitch, 30.08kHz to 50.88kHz external.
Frequency response: 20Hz to 20kHz, ‑3/+1dB.
DS2416 DIGITAL MIXING CARD
Inputs: two off analogue (20‑bit 128‑times oversampling A‑D), one off stereo digital S/PDIF (coaxial).
Outputs: two off analogue (20‑bit eight‑times oversampling D‑A), one off stereo digital S/PDIF (coaxial).
Nominal levels: ‑10dBV.
THD: less than 0.02 percent (20Hz to 20kHz).
Dynamic range: A‑D + D‑A typically 93dBA, D‑A typically 94dBA.
MIXER FACILITIES AVAILABLE ON EACOF THE 26 CHANNELS
Four‑band parametric EQ (12 types), dynamics (six types), six Aux Sends, eight Bus Assigns, Pan, Meter, Fader.
Effects: Effect 1 (39 types), Effect 2 (40 types).
AX44 AUDIO EXPANSION UNIT
Inputs: four off analogue (20‑bit 128‑times oversampling A‑D).
Outputs: four off analogue (18‑bit 8‑times oversampling D‑A), headphone output hardwired to outputs three and four.
Nominal levels: ‑10dBV, but inputs one and two are switchable between Line (‑10dBV) and Mic (‑50dBV) sensitivity.
THD: less than 0.01 percent (20Hz to 20kHz).
Dynamic range: A‑D + D‑A typically 100dBA, D‑A typically 106dBA.
System Requirements
Since so much of the functionality of the DSP Factory is provided by the onboard DSP chips, computer requirements are modest, and depend largely on how many audio channels you want to achieve. Yamaha suggest a minimum of an Intel Pentium 100MHz with 24Mb RAM, and recommend an Intel Pentium 166MHz and 48Mb RAM. For once the question of using other makes of CPU is largely irrelevant, since the audio processing is carried out on the soundcard itself. However, if you want to run DirectX real‑time plug‑ins as well, then an Intel processor is recommended, and preferably a Pentium II.
During my time with the review model, I sometimes found using such a well‑endowed software mixer with a 17‑inch monitor screen a little unwieldy — even at 1280 by 1024 pixels some software will struggle to display more than a section of the mixer. This is a fundamental stumbling block with any digital mixing console controlled via software alone, and each software developer will have a different idea on how to design the user interface so that you can quickly and easily access any parameter without losing sight of the whole picture.
The AX44 Audio Expansion Unit
If you need more inputs and outputs, the AX44 is a neat solution. Housed in a standard 5.25‑inch drive enclosure, this fits in your computer exactly like a CD‑ROM drive, and connects internally by a ribbon cable to the DS2416 card. Four inputs and four outputs are provided, all on quarter‑inch unbalanced jack sockets. The first two inputs each have an associated slide switch which selects either Mic (‑50dBV) or Line (‑10dBV) operation, while the other two are both at Line level. All feature 20‑bit, 128‑times oversampling A‑D converters.
All four outputs are identical, with a ‑10dBV level, and using 18‑bit eight‑times oversampling D‑A converters. In addition, outputs three and four also appear at a headphone output alongside, which has its own level control. A useful touch is the LED power indicator, which can be interrogated from the Check utility — the LED can be made to illuminate by clicking on a button, and this can also be useful if you connect two AX44 units to a single DS2416, and wish to identify which is which.
Since the case provides reasonable shielding from the rest of the computer, noise levels are fairly low, and although you can't expect the mic inputs to compete with those of an external mixing desk, they are still very capable, with a quoted equivalent input noise of 120dBV.
Techno Talk
The bulk of the DSP Factory's clever bits are contained within five Yamaha DSP3 custom DSP chips (three for mixing, one for audio streaming, and one for the effects). These can also be found in both the 02R and 03D mixing consoles, and there is also one on the forthcoming SW1000XG soundcard. Unlike most other manufacturers who use third‑party chips (often from the Motorola range) Yamaha actually design and manufacture their own DSP chips, which are apparently optimised for audio use.
However, there are other proprietary chips on the DSP Factory circuit board — the 20‑bit A‑D converters are CS5335s, made by Crystal Semiconductor, which are also found on the Event Gina/Darla cards. The converters on the AX44 expansion unit are even better, and typical noise levels are several dBs better than on the DS2416 (though these are pretty low already).
The mixer sections feature a 32‑bit data path, 24‑bit coefficient, and 42‑bit accumulator, and the EQ has a 44‑bit data path, 32‑bit coefficient, and 54‑bit accumulator. This all sounds suitably awe‑inspiring, but it is the host software that determines the recorded bit depth, and all the applications I looked at only work at 16‑bit resolution at the time of writing. The same situation applies to aspects like sync'ing to MIDI Clock, MTC, and SMPTE timecode, all of which is dependent on the host software to a large extent. The DS2416 has its own internal clock, but it is up to individual applications to support this facility.
Software has to communicate with the DS2416 using fairly low level API (Application Program Interface) calls, but it is also possible for the software to provide MIDI control of some of the functions, which is apparently what Cakewalk Pro Audio 7.0 does. This means that if any hardware control surface is released, it will also need special drivers — the sheer numbers of possible controls make it difficult for MIDI controllers to be used, and the amount of SysEx data needed for real‑time MIDI automation doesn't bear thinking about.
Pros
- Staggering facilities for the price.
- Effects take no computer processing power.
- Will work well with any make of computer processor.
Cons
- Difficult to control fully using software alone.
- No control software provided.
- Needs a minimum of a 1024 by 768 resolution screen, and preferably a 19‑inch or larger monitor.
- Even after the Mac drivers arrive, the AX44 expansion won't fit Mac computers.
Summary
An extremely versatile and powerful system that will provide high enough audio quality for most people at a bargain price, but very dependent on third‑party support to get the most out of it.