Diamond Monster Sound MX300

Review date: 28 January 1999.
Last modified 03-Dec-2011.


Diamond's Monster Sound MX300 has been widely hailed as the PCI sound card of choice for the discerning gamer, with support for all the popular PC surround sound standards, including the hot new A3D 2.0. At $225 (Australian dollars) for the full retail package, it's expensive for a sound card, but not as expensive as Creative Labs' competing Sound Blaster Live!

If you're a game player, the MX300 jumps all over the SBLive!. Read on to find out why.

What you get

Monster Sound MX300

The MX300, like the MX200, has a black rear panel, with gold plated connectors. The gold connectors won't do anything for your sound - gold terminals are less prone to corrosion, but only if you use gold-plated PLUGS in your gold sockets. But the oh-so-cool black panel has white labelling on it, which makes the Monster Sound cards possibly the first on which the connectors are easily identified.

The MX300 is based on Aureal's Vortex 2 chipset, which gives it hardware support for both the A3D and A3D 2.0 surround sound Application Programming Interfaces (APIs). It also supports Microsoft's DirectSound, DirectSound 3D and with a future driver version will also support DirectSound EAX (Environmental Audio eXtensions). So, in English, there are few surround-sound-supporting games with which the MX300 will not work perfectly. When the EAX-compatible drivers come out, it'll have all bases covered, unless games start using CRL's upcoming Sensaura system - great, another standard, just what we need.

At present the MX300 works just fine with games that support EAX; you just have to live without the EAX reverb effects for the time being, or slow your system down by using CPU-emulated EAX.

At present, A3D 2.0 is clearly the most advanced game sound system. It supports sound locations like the first A3D, but also handles reflections from walls, occluding objects with different levels of permeability, and even Doppler pitch shifting.

The originally released version of the MX300 drivers permitted only a paltry 16 simultaneous positional audio streams. This is not 16 channels of audio divided among the four speakers - this is 16 sounds simultaneously, with each sound delivered through any or all of the four speakers, with the extra processing that enhances the surround effect. The current drivers raise the bar to 32 simultaneous sounds, by using software mixing. You can get them here. The MX300 actually has a total of 76 positional audio channels, but 60 of them are reserved for reflection effects. Aureal promise future driver versions will make more and more of the reflection channels available for primary sound streams.

Not-yet-available optional daughtercards will attach to the "MX-Link" connector on the back of the MX300 and add things like S/PDIF input-output ports with full Dolby Digital 5.1 channel support. This means people with a DVD drive and a software DVD player will be able to hook their PC up to a Dolby Digital home theatre system and get exactly the same sound they'd get from an S/PDIF-equipped DVD player.

This is less important to people that already have an S/PDIF output on a dedicated DVD decoder card, though (see my review of just such a card, the Jaton Magic DVD, here). Chances are your dedicated DVD card only offers S/PDIF output, though, so if you want to get clean digital audio into your computer from elsewhere, an MX300 daughtercard could still be for you. Apparently at least two models are in development (one with RCA-connector electrical S/PDIF, one with optical connectors), but no specifications have yet been released.

You also get a decent little manual, which is odd for Diamond, whose paper documentation is often barely visible to the naked eye.

So how's it sound?

You can set the MX300 to output to two speakers, or four speakers in "dual stereo" mode (the rear speakers make exactly the same sound as the fronts), or proper surround mode with different signals for the rear speakers. You can also use two speakers and plug headphones into the second speaker output, and switch between speakers and 'phones with a System Tray icon.

A3D's main claim to fame is the use of clever cueing manipulation to produce the illusion of surround sound from only two speakers. It does not a bad job of this; at the very least, it impressively extends the soundstage (the apparent area the sound is coming from) without muddying up the audio, which was the problem with old-fashioned attempts at the same thing like IMX. If you never heard "IMX expansion", you missed nothing.

Add another two speakers, and you're really talking. Now sounds behind you definitely ARE behind you, which is both hugely entertaining and actually quite useful in single player and, especially, multiplayer games. Knowing that the footsteps of the guy with the crowbar are behind you can save your life.

A3D's Head Related Transfer Function (HRTF) technology does an even better job with headphones, too. The speaker version is, of necessity, a compromise, because the programmers don't know the specs of the speakers or their location relative to the listener. They also have to include "crosstalk cancellation", to try to minimise the amount of sound meant for one ear which makes it to the other.

With headphones, the speaker position and crosstalk problems go away, and you hear remarkably good actual honest-to-goodness 3D audio, with height, width and depth.

The height cues are the most elusive, but they're still definitely there; you can close your eyes and tell with considerable accuracy when a sound is meant to be above or below you. It's not perfect, but it's good. The result is less impressive when all you have is a 2D speaker array, and less impressive again with the "1D" pair of speakers most people live with.

The modern surround-simulation systems work so well because they have huge amounts of processing power to play with, and because the games they work from can tell them where the sounds are meant to be. Previous systems worked from plain analogue stereo inputs, and had no idea how many sound sources there were or where, precisely, they were meant to be.

However many dimensions you can hear in it, A3D sounds good with two speakers, and much better than unenhanced game sound.

The MX300, used with SoftDVD, can also mix down 5.1 channel Dolby Digital audio from DVDs to four channels. It can also handle games with Dolby Digital sound. Unfortunately, no such games presently exist.

The MX300 also has a very low noise floor - the level of background hiss that determines the quietest sounds you can reproduce. Realistically, gamers don't care much about the signal-to-noise ratio of their sound hardware. If you intend to use the MX300 for music applications, though, the lack of traditional PC background noise is a lovely feature.

The support software includes controls for the hardware 10-band graphic equaliser (EQ) - you set the sliders on your screen, but the sound is processed by the MX300, and so tweaking the bass, mid and treble won't make your computer slower. There are even EQ presets for different kinds of music. Most little computer speakers benefit from a modicum of bass boost - although this makes it easier to overdrive the poor little things if you wind the volume up too far.


The MX300's earlier relative, the MX200 (reviewed here), uses the same Roland Dream 4Mb wavetable daughterboard as the Sound Blaster Live!. The MX300 has a standard wavetable daughterboard connector, but it doesn't have anything plugged into it by default. Instead, the card uses the DLS (DownLoadable Samples) system for MIDI, which uses 4Mb of system memory by default instead of having its own onboard storage. The standard instrument sample set sounds pretty good (maybe not as good as the Dream, but it's a close-run thing), and the nice thing about DLS is that you can easily switch to other sample sets if you like. The MX300 works with the Microsoft DirectMusic standard, and it lets you use sample sets much bigger than 4Mb, if you've got the memory.

Since current computers generally have at least 32Mb of RAM, the 4Mb sample set is not a very big deal. If you want better MIDI and 4Mb of system RAM back you can plug any of a number of daughtercards into the wavetable board connector, but outboard MIDI gear will sound yet better.

The MX300 has 64 hardware MIDI "voices" - it can play 64 notes at once without having to mix sounds. With real-time mixing it can play up to 320 notes at once, but this will significantly slow down the computer. All of this is pretty much irrelevant to most users; gamers playing many current titles will never hear a note of MIDI. If you want to make use of the bundled MidiSoft Studio Recording Session package to compose rather drastically orchestral works, though, the MX300 can handle it, and will do a decent, if not stellar, job.


The MX300 software bundle is OK, but not fabulous. You get "Half-Life - Day One", which is one of those dreaded cut-down "special editions", but pretty good as such things go - you get almost the first quarter of the game.

There's also the arcade tank combat game Recoil, whose chief claim to fame is that it, like Half-Life, supports A3D 2.0. Apart from that, it's an unremarkable shooter. But you do get the full version.

If you're into music, the included MidiSoft Studio Recording Session is a great deal better than the dinky MIDI sequencers included with many sound cards. You can do real composition with this program. Most buyers will never touch it, but if you're into MIDI, you'll be pleasantly surprised.

The outside of the box also promises Zoran's SoftDVD DVD playing software, and, unlike certain Diamond Viper V550 graphics cards I could mention (and do, here), the included CD actually does contain said software. SoftDVD is all very well if you have a DVD-ROM drive, but otherwise useless. It does work well with the MX300, mixing 5.1 channel Dolby Digital sound down to four channels, or even two channels. A hardware DVD decoder card like Jaton's Magic DVD (reviewed here) does the job more elegantly and without functionally paralysing your computer, but hey, it's freebie bundled software. You can't complain.

There's also MusicMatch, an MP3 compression and playback package which comes with the superfast Xing codec. On a 300MHz or faster Pentium machine, MusicMatch can compress CD-quality music to the 12-times-smaller 128 kilobit per second MP3 format in about as much time as the music takes to play. MusicMatch makes it very easy to convert whole CDs to MP3, if your CD-ROM drive supports audio extraction - all current models do, but some produce more listenable results than others. If you've got an Internet connection, MusicMatch even logs into the Compact Disc Database and automatically gets the disc and track names for you.

The Xing codec pays for its speed with marginally lower quality than some other MP3 encoders, but it's a good trade. This version of MusicMatch is not quite the full version - it won't compress WAV files to MP3, but only tracks it's just read from a CD. This is not much of a limitation for most users.


Various problems have been reported with the MX300 driver loading procedure, but they seem to be restricted to the drivers that come with the card. The solution is simple - use the latest drivers (get them here) instead of the bundled ones.

If you're a joystick user, check to make sure your stick will work with the MX300's subtly non-standard game port. Apparently because of the card's 3.3 volt architecture, the game port is incompatible with some older sticks. The original 1997 Monster Sound was renowned for being incompatible with pretty much any joystick you care to name; the MX300 is much, much better but still not perfect.

3D audio has a price - game speed. Fast accelerated boards like the MX300 can greatly reduce that price, but only if you're using their hardware features only. If you use only 16 positional audio channels - which is all that most games currently use - the MX300 allows you to play your games not a lot slower than they'd run without surround sound, even when you're using the all-singing, all-dancing features of A3D 2.0.

The degree of slowdown you see depends on your CPU speed and graphics card. If you have a slow graphics card (an original Voodoo Graphics, for instance) and a fast CPU (a P-II 400, for instance), the extra load on the CPU will not slow it enough for the frame rate to drop significantly; the graphics card is the limiting factor. Turbo machines with 450MHz overclocked Celeron-As (directly equivalent to a Pentium-II 450 for gaming, and pretty much everything else) and really fast video cards like the Diamond Viper V550 (reviewed here) suffer about a 20% frame rate loss with A3D 2.0 sound enabled and lots going on. Low-load performance (single player gaming) is still great, but the loss of speed for frantic multiplayer games can be significant.

If you activate the 32 sound stream mode permitted by the current drivers, you'll get a more significant slowdown - maybe twice as much as you'd otherwise see. But the only game that supports this many sound streams at present is Unreal, and you can choke it down to only 16 streams if you like.

If you're using the DOS Aureal drivers and also have Norton Antivirus on your system, the virus-checker will trigger unnecessarily on the sound card drivers. Edit your AUTOEXEC.BAT file and swap the order of the virus checker and sound card lines, so the sound card drivers load first, and all will be well.

Some users have also reported problems with Cambridge Soundworks five-speaker systems (four satellites and one subwoofer) in which bass is barely audible. This problem also appears with any other speakers that share the same design - four speakers, and a subwoofer that draws signal from both the front and the rear pair - and to a lesser extent in setups with two subwoofers, one driven from the front output and one from the rear. In other words, people who run a pair of regular three-piece subwoofer/satellite systems.

The "absent bass" problem looks like an out of phase signal; the Aureal drivers shift the phase of sound as part of the position cueing process, but they shouldn't do it with the bass, which is canonically nondirectional. The current drivers ought to fix the problem, and it won't arise at all if you don't use dual subwoofers, or dual-input single subs.

How's it stack up?

The obvious competitor for the MX300 is the Sound Blaster Live! in its full and Value incarnations. The full SBLive has S/PDIF in and out connectors, MIDI connectors and a special digital speaker output connector (which can support up to eight speakers but at present works with exactly one speaker system, coincidentally made by Cambridge Soundworks, a subsidiary of Creative...), but it costs more than twice as much as the MX300. The upcoming MX-Link boards for the MX300 promise to give it most if not all of these features. The Value version of the SBLive doesn't have the extra connectors, but still costs a bit more than the MX300, and is unexpandable.

The SBLive supports DirectSound 3D and EAX, but not A3D 1 or 2. The MX300 doesn't yet support EAX, but we're promised it will with an upcoming driver release; the SBLive will never support A3D. A3D is Aureal's proprietary standard, which only cards based on their designs can use; EAX was created by Creative Labs, makers of the Sound Blaster line, but it's an open standard and anyone can make gear that uses it.

When Creative release the EAX 2.0 standard, which will include the same sort of extra bits as A3D 2.0 currently does, the SBLive will support it and may well sound as good as the MX300 - as long, of course, as you're playing games with EAX 2 support.


The first priority for those building a freckle-kicking gaming computer is a fast CPU and graphics card. But the MX300 should be next on the shopping list. It adds something to pretty much any game, adds a great deal to A3D 2.0 compatible games, and isn't very expensive - certainly not compared with the Sound Blaster Live!.

For gamers, the MX300 is the best sound card you can buy. For hard core music folk, the MX300 plus one of the upcoming MX-Link cards should compete very favourably, considering the price, with far more expensive offerings from the likes of Turtle Beach.

If you play games, and you're in the market for something to replace your old plain-stereo ISA sound card, the MX300 is the only horse in the race.




  • Great sound!
  • Supports, or shortly will, every 3D audio standard
  • Cheap for what you get
  • Doesn't work with EAX - yet.
  • Current drivers not too fast for 3D sound
  • Not great value if you don't play games


A3D - Aureal's proprietary PC surround sound standard. Version 1 of A3D is much like Creative's competing standard EAX; version 2 of A3D can more accurately simulate how sound sources in a complex environment behave, by using information on the shape of the environment provided by the game. A3D 1 and EAX have no real idea what shape a room is - they only know where the sound sources are within it.

Codec - Short for compressor/decompressor, a codec is software or hardware for compressing and decompressing data.

EAX - Environmental Audio eXtensions, the PC environmental reverb standard created by Creative Labs, makers of the Sound Blaster line, but made an open standard for anyone to use. The plain "EAX 1" originally available implements environmental audio effects by using pre-programmed presets of much the same nature as those used by home theatre amplifiers for ambience enhancement - stage, hall and room reverb, for instance. The various presets can be further tweaked, but EAX 1 has no ability to truly simulate how things would sound in a particular shape of room, especially when you start taking closed doors, obstacles and fancy reflections into account. EAX actually doesn't have anything to do with positional audio - by itself, it's just reverb, and a game must also support DirectSound 3D if sounds are to come from particular locations. EAX 2 has positional audio and room-shape support, like A3D 2.0, but it's not widely supported yet. Neither is A3D 2.0, really, but at least it's ahead of EAX 2.

PCI - Peripheral Component Interconnect, the standard for PC expansion cards that replaced the venerable ISA (Industry Standard Architecture). PCI sound cards don't, inherently, sound any better than ISA ones, but they take up a bit less CPU time. On the other hand, some PCI sound cards don't work at all in DOS. The MX300, however, does, so old DOS software that you don't want to run from Windows won't be silent. The MX300 only emulates an old Sound Blaster Pro in DOS mode, though; the Sound Blaster Live! emulates the more recent SB16.

Phase - Phase is best described as the "polarity" of a signal. Audio signals in your speaker wires are alternating current, with the rapidity of the alternations corresponding directly to the motion of the speaker cones and the pitch of the sound that comes out. When the signal is positive, the speaker cones should move outwards (towards the listener), unless the speaker's been connected backwards (some speakers are connected backwards inside). Signals are said to be "out of phase" when they're oppositely polarised, like these two waveform examples:

phase160.GIF (897 bytes)

phaseb160.GIF (901 bytes)

If these two signals are both sent to one speaker, no sound will come out at all - adding them together gives nothing. If they're played out of two different speakers, though, a listener between the two speakers will have sound of one phase in one ear and sound of the other phase in the other ear, not to mention various wall reflections. This sounds weird in a distinctive way. If you have speakers on your computer or hi-fi with wires going to spring or screw terminals on the back, try reversing the wires on one of the speakers and you'll see what I mean. Connecting your speakers out of phase is a classic hi-fi setup mistake.

Along with the odd sound, you'll get significantly less bass, because bass sound waves have a long enough wavelength that two separate speakers can easily interfere with each other, if they're out of phase. It's like sending two out of phase signals to one speaker, only less so.

S/PDIF - Sony/Philips Digital Interface Format is an audio transfer protocol that can use either optical or electrical connectors - electrical, in this case. It's used to transfer either 16 bit stereo audio data between various components (CD players, Digital Audio Tape decks, some sound cards), or to transfer Dolby Digital (formerly known as AC-3) 5.1 channel audio for movies. If you've got a home theatre amplifier with an S/PDIF input, you can hook it straight up to the Jaton decoder card and enjoy Dolby Digital surround sound from any DVD that features it. Click here to jump to the sidebar on DVD movie audio.

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