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Ego Sys Wami Rack 24

Digital Audio & MIDI Soundcard By Martin Walker
Published September 2000

Ego Sys Wami Rack 24

A new PCI soundcard and breakout box system from Ego Sys combines analogue and digital audio, MIDI, and a host of synchronisation and driver options, and all without breaking the bank. Martin Walker wonders if this might be all you ever need...

Ego Systems (Ego Sys to their mates) are a Korean company with an intriguing range of hi‑tech products. These include the Waveterminal U24, claimed to be the world's first 24‑bit USB audio interface, and the WaMi Box, a high‑quality audio/MIDI solution for notebook users. There are also a couple of dedicated four‑in/four‑out MIDI interfaces in their range — one each for USB and serial‑port use — and the Dr D digital box for optical, co‑axial, and AES/EBU conversion.

Their range also currently includes two PC soundcards. The Waveterminal 2496 has two 24/96‑capable analogue inputs and outputs, along with co‑axial S/PDIF I/O, and is obviously intended for professional use, with balanced/unbalanced connectors running at +4dBu levels and comprehensive driver support including ASIO 2.0, DirectSound, and Gigasampler GSIF. However, their flagship soundcard is the one I'm looking at in this review — the WaMi Rack 24. The name is derived from an amalgamation of 'Wave' and 'MIDI', and from the fact that its two‑part design features not only a PCI expansion card, but also a 19‑inch rackmounting case.

As you might expect, the WaMi Rack's four analogue inputs and eight analogue outputs are 24‑bit/96kHz‑capable, and can be run at either ‑10dBV or +4dBu levels with either balanced or unbalanced connections. The inputs also feature a further preamp which provides enough gain to directly connect mics, and in this mode there is also the option of phantom power. On the digital audio side, there are both co‑axial and optical S/PDIF In and Out, word clock In and Out, and even a built‑in real‑time sample‑rate converter, while there is also a generous complement of four MIDI Ins and Outs, SMPTE In and Out, and a front panel that sports a comprehensive selection of LED indicators showing MIDI activity and analogue output levels.


With four analogue inputs and eight analogue outputs, along with ASIO 2.0 drivers capable of 7mS latency and 'zero' latency Direct Monitoring, the audio spec of the WaMi Rack 24 should suit plenty of musicians.With four analogue inputs and eight analogue outputs, along with ASIO 2.0 drivers capable of 7mS latency and 'zero' latency Direct Monitoring, the audio spec of the WaMi Rack 24 should suit plenty of musicians.

The PCI expansion card is five inches long, and its backplate has just two connectors — a 44‑pin socket for the umbilical connection to the rackmount unit, and a phono socket for CD digital audio output. This is directly connected to a 2‑pin socket on the card itself, into which you can plug the S/PDIF digital output from a suitable CD‑ROM drive using an internal cable. The phono socket can then be connected via a suitable lead to the co‑axial digital input on the rack unit.

Two further 2‑pin sockets on the card, labelled Sync In and Out, are to connect together multiple cards — apparently the drivers can link up to four cards with sample‑accurate sync. A couple of generous two‑foot‑long leads are provided for this purpose, along with a five‑foot‑long umbilical cable for connecting between the card and rack unit.

The 1U‑high rackmount case is made out of cast iron and steel, which makes it rugged and quite heavy. The general standard of internal construction also appears good, with neat layout and tidy cabling. Its top panel is impressed with the Ego Sys logo, and the 3mm‑thick front panel features an attractive grey‑speckled finish, several logos and badges, and a variety of differently coloured LED indicators grouped across a 9cm‑long perspex insert towards its left‑hand end. The top two‑thirds of this perspex strip holds eight 8‑segment LED ladder displays showing analogue output levels, while beneath these from left to right are a red PWR indicator, green COM LED indicating successful MIDI communication, two yellow LEDs showing SMPTE In activity and SMPTE Out generation, and four dual‑purpose MIDI LEDs. These latter four illuminate red to show MIDI In activity, and green to show MIDI Out activity for their respective interface. At the other end of the front panel is a red rocker switch for mains power.

The back panel is awash with sockets. Starting on the left‑hand side there is a fused IEC mains socket for the internal power supply, followed by four five‑pin DIN sockets for the MIDI Inputs, and a further four for the MIDI Outputs. The other half of the panel has two rows of sockets. First are the eight TRS‑wired quarter‑inch jack sockets for the analogue outputs, and above these are four more for the analogue inputs, followed by a pair of Toslink optical sockets for S/PDIF digital I/O, and a further pair of quarter‑inch jack sockets for SMPTE In and Out. Then comes a vertically mounted pair of BNC sockets for word clock In and Out, and finally the 44‑pin umbilical connector with a pair of phono sockets above it for co‑axial S/PDIF In and Out.

Installation And Setup

The WaMi Rack 24 Control Desk utility provides a wealth of control options in a single compact panel, making it easy to see the current configuration at a glance.The WaMi Rack 24 Control Desk utility provides a wealth of control options in a single compact panel, making it easy to see the current configuration at a glance.

As I half expected, the supplied floppy disk containing version 1.5 drivers was already redundant, since a version 1.7 update had just become available from Ego Sys' download page. I downloaded the single 311K zipped file containing these driver files, and then unzipped them into a suitable folder on my hard drive. For those who are updating previously installed drivers to a new version, Ego Sys provide the EgoClear utility which will remove all traces of your old drivers from the Registry — you can then install the driver update.

As with many soundcards designed primarily for musicians, the software bells and whistles are wisely kept to a minimum, and the WaMi Rack driver and utility software comprises just nine files (including a release note detailing the driver change history), with a total size of just 735K. When you reach the desktop there is just a discreet WaMi icon on the Taskbar to show that the WaMi Rack 24 Control Desk has been installed and is operational. By the way, the rack unit must be switched on before you boot your PC, otherwise it won't be recognised by the drivers.

Staying In Control

The two‑pin Sync sockets on the WaMi Rack 24's PCI card can be used to connect up to four cards with sample‑ accurate sync. The other two‑pin socket allows you to connect the digital output of your computer's internal CD‑ROM drive.The two‑pin Sync sockets on the WaMi Rack 24's PCI card can be used to connect up to four cards with sample‑ accurate sync. The other two‑pin socket allows you to connect the digital output of your computer's internal CD‑ROM drive.

The Control Desk consists of a single window, and its title bar usefully displays the driver version and its release date, while the remainder of the window is divided into three main areas — digital input and clock options are down the left‑hand side, analogue input options are in the middle, and sample rate, monitoring, output, and SMPTE options are on the right hand side. Starting with the central area first, there are four rotary controls for input level, which are fully variable in 0.5dB steps over a 63dB range, with text readout of the current value in the boxes beneath. The remaining input controls all affect the inputs in stereo pairs (1/2 and 3/4), and there are also a couple of Gang buttons to adjust the appropriate input level controls in sync for stereo recording. Beneath these are the input gain switches. You can select +4dBu or ‑10dBV sensitivity for each pair, and in each case a further pair of buttons show the gain setting depending on whether you are using balanced or unbalanced wiring (there is a 6dB difference).

Clicking on the Mic On buttons switches into circuit a preamp with an extra 45dB of gain for either or both input pairs, and the Phantom Power buttons below these activate +12V phantom power for use with condenser and electret mics. Ego Sys claim on their web site that although phantom power standards include 12 Volts, 24 Volts, and 48 Volts, most modern condenser mics should work quite happily with just 12 Volts, although I suspect that headroom may be lower than with the more common 48V standard.

On the left‑hand side of the Control Desk are a series of buttons for the digital functions. Here you select an appropriate clock source — Internal if you're using the soundcard as a master clock, Digital In when receiving signals from other equipment such as a DAT or Minidisc playback, Word Clock if you have a suitable external master clock, and WaMi to WaMi if you have multiple cards and want to slave additional ones to the one you are using as master. Word clock can be switched between Fs and 256x Fs — the correct setting depends on what other gear you are using, but many Digidesign products supply 256x Fs word clock. The Digital Output type can be selected from either Consumer (IEC958 Type II) or Professional (IEC958 Type I) to set the appropriate flags. Ego Sys suggest using their Dr D converter box if you have older AES‑EBU digital gear that requires a higher signal level.

Three buttons are grouped together under the heading 'In 3,4 Select', and they are labelled Analog (sic), Coaxial, and Optical. These choose which one of the three input sockets is connected to Inputs 3 and 4 when monitoring or recording, since unlike some other soundcards the digital input is an either/or option rather than a separate extra input. However, even if you are using all four analogue inputs, you can still select either the co‑axial or optical input for clock purposes when the Clock Source is set to Digital In.

The final pair of On and Off buttons at this side of the panel are at the top, and labelled 'Digital Input with SRC'. These switch in and out a real‑time sample‑rate converter. When activated you can change the sample rate of an incoming signal at either the co‑axial or optical inputs to a different rate by choosing the Internal clock source option, and then selecting the output sample rate from the buttons at the top of the right‑hand section of the Control Desk. Six rates are provided, grouped in three pairs — 32 and 64kHz, 44.1 and 88.2kHz, and 48 and 96kHz. The only restriction is that the maximum conversion rate is 3:1, so for instance an 11kHz input signal can only be converted as far as 32kHz, or a 96kHz one down to 32kHz. An Auto button below the sample‑rate selectors sets the rate automatically depending either on the choice within your music application, or by the embedded clock signal from a digital input.

Also on the right‑hand side are buttons to switch the nominal analogue Output Level between +4dBu balanced or ‑10dBV unbalanced operation. However, there is also 20dB headroom: I measured the output level for an 0dBFS playback signal at the +4dBu setting, and I found it to be 11.86V RMS, which equates to a very healthy +23.7dBu. All three input gain modes (+4dBu, ‑10dBV, and Mic) along with phantom power and output level selection are switched remotely using relays in the rack unit — you can hear them click on and off when you change a setting in Control Desk — which keeps the analogue audio circuitry well out of the way of digital control signals, ensuring optimum audio quality.

Two more sets of buttons control 'zero'‑latency hardware monitoring of input signals. Input pairs 1/2 and 3/4 can each be monitored through any one of the four output pairs, and if required both pairs can be routed to the same output. Given that mixing together two full‑scale input signals would produce a combined signal that exceeds 0dB digital level, there are also two mixing options — Dynamic leaves the combined level as it is, and you will hear clipping distortion if you don't reduce the input signal levels at source, while Soft reduces the monitored signal level automatically by 6dB to avoid overload.

The final controls on the right‑hand area are for the SMPTE display: the Show/Hide button launches an add‑on panel at the bottom of Control Desk, and here you can select from the five frame rates of 24, 25, 29.97, 30D (drop), and 30 frames per second, while a large numerical display shows the current timecode value. You can increment any digit of the start time using the left‑hand mouse button, and reset it to zero using the right‑hand mouse button. Owners of wheel mice can also use their central wheel to alter these values. A start/stop button starts timecode generation.

Right‑clicking anywhere over the main control area launches a floating menu with a few more options including a 'Stay on Top' function and a Full Reset of all controls to their default settings. Overall I found Control Desk straightforward and easy to use, and the illuminated 'LED' style graphics show its current status clearly.

A Cornucopia Of Drivers

As well as offering four analogue inputs, eight analogue outputs and two choices of digital I/O, the WaMi Rack 24 also provides more MIDI Ins and Outs than any other soundcard I've reviewed to date, as well as word clock and SMPTE sync facilities.As well as offering four analogue inputs, eight analogue outputs and two choices of digital I/O, the WaMi Rack 24 also provides more MIDI Ins and Outs than any other soundcard I've reviewed to date, as well as word clock and SMPTE sync facilities.

Driver support for the WaMi Rack 24 is possibly the most comprehensive that I've seen in any soundcard to date, and formats include MME, DirectSound, ASIO 2.0, EASI, and GSIF (see the 'Driving A Hard Bargain' box for full details). Various driver options are available from the right‑click floating menu — you can individually disable each of the four outputs of the EASI driver, disable/enable the Gigasampler driver, disable the DirectSound driver or select one of the four output pairs for this purpose, and choose the MME buffer size from a selection of 4, 8, 16, or 32K.

There are no options to selectively disable ASIO inputs and outputs, but the ASIO 2.0 drivers do provide five options for DMA buffer size, giving latency values of 7mS to 94mS. My Pentium II 450MHz was quite happy at the 13mS setting, but exhibited an occasional click on the fastest 7mS one — however, if your PC has a faster processor it may well manage this. ASIO 2.0 Direct Monitoring is also available if you prefer to use this rather than the Control Desk facilities. I did find one bug in the driver — every time I changed the ASIO buffer value, the Cubase 5.0 CPU indicator shot to 100 percent and stayed there, the soundcard refusing to play back again until I rebooted Cubase.

The MME drivers appear to Windows applications as WaMi Rack 24 In 1‑1/2, and In 1‑3/4, while the four pairs of outputs are WaMi Rack 24 Out 1‑1/2, Out 1‑3/4, out 1‑5/6, and Out 1‑7/8. This suggests that multiple WaMi Racks may automatically appear as Out 2, and so on, although I wasn't able to confirm this. There are four MIDI Inputs and four MIDI Outputs, with names along similar lines to the audio ones, plus a fifth one labelled WaMi Rack 24 SMPTE In for use by your MIDI sequencer. The DirectSound drivers appeared to work quite well, and I managed a 20mS Play Ahead setting in Reaktor, and 27mS latency using VAZ Modular. However, if you change the output pair for the DirectSound driver your PC will need a reboot before this takes effect.

In Use

As always, I started out with comparative 16‑bit listening tests against my Echo Gina, after carefully balancing the two soundcard levels using a 1kHz sine wave test tone. As expected, the 24‑bit converters of the WaMi Rack were noticeably better than those of the 20‑bit Gina, but I don't think I've ever noticed such a difference in smoothness — the WaMi Rack made the Gina sound positively shrill and harsh by comparison, especially on female vocals! Listening with a wide variety of material including unaccompanied voice, solo drum kit, jazz quartet, and rock ensemble, the WaMi Rack 24 sounded balanced and natural — just what you need from a soundcard.

Internally the resolution of the WaMi Rack 24 is 32‑bit, although recorded data will of course play back at any sample resolution supported by your software, including 16‑ and 24‑bit. Even if you are making recordings for CD or other 16‑bit format, they will still benefit from being recorded with the 24‑bit resolution of the A‑D converters, processed at 32‑bit resolution, and then dithered down to 16 bits for a higher‑quality final signal. Strangely, both the box and owner's manual claim only that sample rates of up to 48kHz are supported, but apparently support for the higher sample rates of 64kHz, 88.2kHz, and 96kHz was added in a firmware upgrade as part of the version 1.5 drivers. I certainly recorded some tracks at 96kHz which sounded very good, and so can confirm that this now works.

RMS background noise measurements using Wavelab 3.0 measured ‑93dB for 16‑bit/44.1kHz, while those at 24‑bit/44.1kHz dropped to ‑100dB, rising slightly to ‑98dB when the bandwidth was opened out to 24‑bit/96kHz. All measurements were taken with gain controls set to 0dB, and input sensitivity at +4dBu. Results at the ‑10dBV setting were identical at 16 bits, and about 1dB worse at 24 bits. Although I've measured lower noise levels on several other cards, these are still all good results, and I think any owner would be pleased with the analogue audio performance of the WaMi Rack 24.

The eight‑step LED ladder meters on the rack unit show playback levels for each of the eight channels, but have no front‑panel calibrations. However, according to my tests they are set to ‑23, ‑20, ‑17, ‑15, ‑10, ‑6, ‑4, and ‑1dBFS. It would possibly have been more useful to instead have four 16‑step displays to show more accurate input levels during recording, but the ones provided are nevertheless handy.

After digitally transferring data to and from a DAT recorder, I found that the WaMi Rack 24 doesn't produce bit‑for‑bit copies, but the only difference between the two was low‑level dither noise, which shouldn't bother most users. Sample‑rate conversion also sounded good, and this feature could be particularly useful when importing 48kHz DAT recordings to use in a 44.1kHz CD burning project. Overall the WaMi Rack 24 has very good performance, and the owner's manual explains all its functions in great detail — apart from covering the Control Desk options it also includes a SMPTE primer, details of suitable balanced and unbalanced cable wiring, and the setting up of applications such as Cakewalk Pro Audio 9.0, Cubase VST 3.7, Logic Audio, and Gigasampler 1.6.

Final Thoughts

The WaMi Rack 24 is a well‑designed product with a unique set of features, and ought to sell well, especially at £499. It doesn't have any direct competitors, and the only other four‑in/eight‑out system I've reviewed is Lexicon's Core 2, which is rather more expensive. If you want rackmounting converters and eight outputs in a similar price range then you should also look at the Gadget Labs Wave/8•24 at around £449, although digital I/O is an optional extra and the highest supported sample rate is 48kHz, or Terratec's EWS88MT, which does include co‑axial digital I/O and retails at £399. If you want more than one MIDI In and Out, one of the few other soundcards to offer this is the SEKD Siena, now at £349, which provides eight‑in/eight‑out analogue I/O, two MIDI Ins and two MIDI Outs, but no digital I/O, and no rackmounted converters.

Ultimately, you should always judge a soundcard by its performance as well as by its feature set, and the WaMi Rack 24 is no slouch in either department. If four analogue inputs are enough for your purposes, and you want both co‑axial and optical digital I/O to interface existing gear like DAT and Minidisc recorders, then it ought to go on your shortlist. However, I suspect that two features in particular will make it popular among musicians — real‑time sample‑rate conversion, and multiple MIDI I/O. The first can save time, and the second money — if you don't fancy having to buy a separate MIDI interface then the WaMi Rack 24 might prove the perfect solution.

Brief Specifications

  • Hardware format: 32‑bit PCI buss mastering expansion card.
  • Analogue I/O: four inputs, eight outputs.
  • Analogue connectors: balanced/unbalanced gold‑plated TRS‑wired quarter‑inch jack sockets.
  • Input/output levels: ‑10dBV or +4dBu nominal.
  • Switchable mic preamps: 45dB fixed gain with switchable +12V phantom power.
  • A‑D and D‑A conversion: 24‑bit.
  • Dynamic Range: 120dB (A‑weighted) measured at ‑60dBFS.
  • Signal to Noise: 120dB (A‑weighted).
  • THD + Noise: 100dB at ‑0.5dBFS.
  • Supported bit depths: 8, 16, and 24.
  • Internal resolution: 32‑bit.
  • Supported sample rates: 32, 44.1, 48, 64, 88.2, and 96kHz.
  • Frequency response: 10Hz to 22kHz (no deviation quoted).
  • Digital I/O: co‑axial and optical S/PDIF with up to 24‑bit resolution.
  • Word clock: supports normal and 256x Super Clock formats.
  • MIDI: four MIDI Ins, four MIDI Outs, and 64 MIDI channels.
  • SMPTE: reads and writes all formats including 24,25,29.97, and 30 drop and non‑drop.

Driving A Hard Bargain

The following drivers are available for the WaMi Rack 24:

  • MME MIDI: four inputs, four outputs, one SMPTE, running with Windows 95/98.
  • MME Wave: 16‑, 24‑, and 32‑bit, four inputs, eight outputs, running with Windows 95/98.
  • DirectSound: 16‑bit, two outputs, running with Windows 95/98.
  • ASIO 2.0: 32‑bit, four inputs, eight outputs, running with Cubase VST 3.7 or later.
  • EASI: 32‑bit, four inputs, eight outputs, running with Logic Audio Platinum 4.04 or later.
  • GSIF 1.6: 32‑bit, eight outputs, running with Gigasampler 1.6.

System Requirements

The bare minimum requirements are a Pentium 166MHz CPU and 32Mb of RAM running Windows 95, 98, or 98SE, although a Pentium II 233MHz and 64Mb of RAM are recommended. However, Ego Sys are unusually forthcoming on their web site about other options, and WaMi Rack 24 is declared fully compatible with Athlon processors. Those using motherboards with a VIA chipset may have possible conflicts if they are running Windows 95 or 98 (but not Windows 98SE), but there is a link to the Viatech web site so that you can update your chipset drivers to solve this problem. Mac drivers are being developed at the moment, and there are apparently plans to support Windows 2000 as well as Windows NT, although no dates are given. However, BeOS and Linux drivers are definitely not on the cards.


  • Good sound quality and support for up to 24‑bit/96kHz.
  • Enough MIDI I/O to allow many musicians to do without a dedicated multi‑port MIDI interface.
  • Comprehensive digital audio and sync options, including word clock and SMPTE.
  • Wide range of driver support.
  • 'Zero'‑latency hardware monitoring.


  • Only two analogue inputs when the digital input is in use.
  • No support for Mac, Windows NT or 2000 at the moment.


The Ego Sys WaMi Rack 24 provides a carefully thought out combination of high‑quality audio and MIDI features that could deliver everything many musicians will ever need in a single package. It is also excellent value for money.