Steinberg Midex 8

MIDI Interface

Reviews : MIDI Interface



Musicians using Mac and PC sequencers often complain about loose MIDI timing. Martin Walker checks out an interface from Steinberg which should solve this problem -- at least for users of their sequencing software...



Steinberg's Midex 8, like Emagic's existing AMT8 and Unitor 8, is designed to provide much tighter MIDI timing than traditional Mac/PC MIDI interfaces, at least within their own sequencer, by using an 'intelligent' buffering system to clock data out (see the How LTB Works box). Data can be sent from multiple ports simultaneously, which is a big improvement over a standard serial or parallel-port MIDI interface where the more ports there are, the more the delays can accumulate.



The Midex 8 has eight MIDI Ins and eight MIDI Outs, supporting a total of 128 independent MIDI channels, and connects to your computer via a high-speed 12Mbit/second USB connector (unlike the AMT8, there is no serial

STEINBERG MIDEX 8 £299

pros

Rock-solid sub-millisecond timing that bypasses USB and operating-system uncertainties.

Useful MIDI cable check and Thru modes.

cons

Multiple Midex 8 devices can only be currently run under Windows ME.

Windows 98 owners will need to upgrade to Windows 98SE.

Current PC drivers not multi-client.

No SMPTE or patchbay facilities.

No Mac drivers yet.

summary

A no-nonsense eight-in/eight-out MIDI interface that provides the tightest timing currently available to Cubase and Nuendo owners, and which suffers from none of the current USB problems.



-port option). The USB buss normally provides the power as well, although you can use an external power supply if you wish (see the Power And USB box).



It features a 'designer' 1U desktop case with optional brushed-aluminium end cheeks for rackmounting. On the front panel are a pair of MIDI sockets for In 8 and Out 8, useful Cablecheck/Panic and MIDI Thru buttons (more on these in a moment), a blue power LED, and two sets of eight numerically shaped red indicators displaying MIDI In and Out activity. These convey far more information from the other side of the studio than standard LEDs, but it's a shame that all the indicators share a common transparent moulding, since some light leaks from one to the next -- at some angles this results in an adjacent inactive digit being nearly as bright as an active one. The back panel contains all eight MIDI output sockets (Out 8 duplicates the front-panel one) and seven MIDI input sockets, as well as connectors for USB, the optional PSU, and a LED sensitivity preset which lets you adjust the MIDI display timing using a small screwdriver. A three-metre-long USB cable is also supplied, which should be adequate for most studios.



A short press of the Cablecheck/Panic button tests a MIDI cable plugged between the front-panel MIDI In and Out sockets, while pressing the button for longer than a few seconds sends out a series of All Notes Off and Controller Reset messages to all MIDI outputs. The MIDI Thru button toggles between two modes that send data to all eight outputs from either MIDI In 1 on the back panel or In 8 on the front. This is handy when you want to control several synths from a single keyboard for instance, and Thru mode gets deactivated automatically as soon as any application starts sending data to the inputs or outputs. This partly compensates for the lack of any dedicated patchbay features such as those offered by Emagic's AMT8 and Unitor 8, though you will need to use an external PSU if you want to use this feature when the computer isn't powered up. Holding both buttons down for several seconds causes a full reset, equivalent to unplugging the Midex 8 from USB. However, although this reset function is handy, as is the ability to hot-swap any USB peripheral, the Windows user should never do either with the Midex 8 while a MIDI application is using it, since this will cause a crash.



There are no SMPTE read or write features at all, which may disappoint some musicians, especially as Emagic's Unitor 8 offers them. Steinberg's take on this is that the best place for any sync features is on the

How LTB Improves MIDI Timing On Playback

Steinberg and Emagic made headlines at the 1998 Frankfurt Musik Messe, when they announced that they would in future share certain aspects of their expertise. Unfortunately this camaraderie didn't last very long, as Emagic later decided to develop their own 'improved' version of ASIO called EASI, and Steinberg took Emagic's existing AMT (Active MIDI Transmission) technology and created their own 'improved' Linear Time Base technology. LTB is used for the first time in the Midex 8.



Both require specially written code in their host sequencer application to benefit, which is why the Midex 8 will only deliver improved timing with Cubase VST 5.0 or Nuendo 1.5 (and Emagic's AMT with Logic Audio 4.0.1 or higher). In essence, both do exactly the same thing. Once MIDI data has been recorded, the sequencer sends it ahead of time to the MIDI interface, where it's stored in a temporary buffer. Then a high-resolution clock inside the MIDI interface sends the time-stamped data out at exactly the right time.



This overcomes the sometimes temperamental nature of both the Universal Serial Buss and the operating system, since the interface doesn't have to rely on smooth delivery of data in real time. As long as enough data is sent in advance (even in fits and starts) to keep the buffer topped up, the AMT8, Midex 8, or Unitor 8 will be able to carry on with perfect precision. It also means that MIDI data can emerge at precisely the same time from each of the eight MIDI ports when required, which again would be a problem for any standard multi-port USB MIDI interface.



Bear in mind that just as with VST Instruments, your MIDI timing won't be any more precise during recording -- it's only on playback that higher precision timing kicks in -- so you won't gain anything from LTB or AMT when attempting to capture the subtleties of a live performance. Nor can these technologies overcome the serial nature of MIDI itself: if you send 16 simultaneous notes to a single MIDI port, once on each channel, then they will still emerge as a serial stream lasting 16mS. That's MIDI for you.



audio card, since nowadays this is the timing heart of many studios. I can see their point, but it does mean that if you want the timing of LTB with sync features, you'll either have to buy an audio card with sync capability, or an expensive stand-alone product such as Steinberg's Timelock Pro as well.



Installation



As with nearly all USB peripherals, installation is simplicity itself: you just plug in the Midex 8 'on the fly', and a few seconds later Windows recognises it, requests the drivers disk and installs the drivers. Well, it does as long as you run Windows 98SE, Windows ME, or Windows 2000. Mac OS and Mac OMS drivers are still in preparation, and apparently Steinberg's drivers are not recognised by any version of Windows older than Windows 98SE, so those with the original Windows 98 release will have to upgrade. A Microsoft USB Fix file is also supplied on the CD-ROM to update the Windows 98SE USB drivers so that the Midex 8 is still recognised after temporarily unplugging it from USB.



Steinberg use the WDM (Win32 Driver Model) for the Midex 8 drivers, which means that you can only use more than one Midex 8 when running Windows ME. This is because both Windows 98SE and 2000 currently have a restriction of 10 MIDI ports when using WDM drivers. Before you panic, let me point out that this doesn't apply to the VXD drivers still used by most other MIDI devices, and in my Windows 98SE-equipped PC I successfully ran various other MIDI hardware and soft synths with MIDI support alongside the Midex 8, with a total of 11 Ins and 21 Outs.



Once the drivers have been installed, any standard MIDI application can use the Midex 8 in the normal way. However, the only way to gain the benefits of LTB technology is to use it with an application that's LTB-aware. Currently there are only two such applications: Cubase 5.0 and Nuendo 1.5. Cubase 5.0 recognises the Midex 8 automatically from revision 2, but if you're still using 5.0 or 5.0 revision 1 you'll also need to run the UPDMROS.EXE utility supplied on the CD-ROM to update a few files.



Steinberg also recommend deactivating the MIDI 'Reset on Stop' function to prevent audio dropouts with low latency settings, and ensuring that the System Preroll setting is at least 100mS to maintain a stable MIDI output with lots of audio tracks.



In Use



I had no problems at all using the Midex 8, and the timing certainly sounded very tight -- but is it actually better than a standard MIDI interface? To check this out I used the test described in my March 2000 PC Musician article, by first creating a MID

Power And USB

Each Midex 8 you plug in is normally powered from the USB buss, but you can plug in any external AC or DC power supply capable of supplying 500mA at anywhere between six and 12 Volts. This will let you use the interface without powering up your computer, which could be useful on occasion.



The Midex 8 is an 'end' device, so each one you plug in will need its own USB port. In addition, those with complex setups who want to install multiple Midex 8s (only currently available if running Windows ME) should note that the USB buss of a computer can only supply up to 1 Amp, which will only power two interfaces. If you run out of suitable ports and want to use a USB hub to provide more, make sure you buy a self-powered one, and that each of its ports can provide more than the 400mA required by each Midex 8. A buss-powered hub only supplies up to 100mA per output, which is not sufficient, so in this case you would need an external PSU.



I part containing continuous hi-hats on every 16th note (ie. four to each beat), copying this part to 16 other MIDI tracks, and then allocating the first part to a VST Instrument drum synth (I used Steinberg's LM9), and the other 16 to each and every channel simultaneously of various MIDI ports.



Next I panned the VST Instrument hard left on my hardware mixer, and the output of my various MIDI synths hard right, and played the song back at 120bpm. Each beat of the VST Instrument is sample-accurate, and will emerge every 125mS or 5513 samples apart, so if you record the two audio signals into a stereo audio track, any MIDI timing discrepancy can be measured by examining the relative positions of the sample-accurate VST Instrument in the left channel and the MIDI drum source in the right channel of the waveform.



The timing between adjacent MIDI beats using the Midex 8 proved to be considerably tighter than several standard MIDI interfaces I tried for comparison purposes. With the standard interfaces, timing varied by up to 2.4mS (105 samples at 44.1kHz), but by only 0.3mS (just 13 samples) with the Midex 8. The Midex 8's timing also seemed fairly consistent as I loaded the other ports with MIDI data, while that of standard multi-port devices tended to get worse as more and more data was sent to them.



Of course, the MIDI protocol itself still limits the density of data that can be transmitted successfully, and when I continued adding tracks full of aftertouch, pitch-bend and other controller data I could still eventually choke the Midex 8 to the point where it spat out notes with almost random timing, just like any other interface. The important thing is that until this happens, Cubase users will find that the Midex 8 keeps their timing far more solid than any other MIDI interface.



Steinberg wisely recommend not connecting other USB devices to the same port if they have 'fluctuating bandwidth requirements', and at the very least not using them at the same time. I plugged in my USB modem

System Requirements

I/O CONNECTION

USB



POWER

Self-powered from USB or optional external PSU (AC or DC, 6 to 12 Volts, 500mA).



OPERATING SYSTEM

Windows 98SE or 2000 (only one Midex 8 supported).

Windows ME (supports multiple Midex 8s).



HOST APPLICATION

Cubase VST 5.0 or 5.0 revision 1 (needs supplied UPDMROS.EXE update)

Cubase VST 5.0 revision 2 or later (recognises Midex 8 automatically).

Nuendo 1.5.



and didn't experience any difficulties during the course of the review, although it made the Midex 8 choke with less controller data. This is as you would expect, since each USB device takes some of the finite bandwidth available, but the beauty of USB is that you can unplug your other devices 'on the fly'.



A few users have reported Midex 8 problems which have been traced to the USB Controller chips in their PCs: hopefully most SOS readers know all about this problem with certain USB chip sets already. The audio crackling problem reported by RME on their web site when using USB MIDI interfaces and low audio latency doesn't affect the Midex 8 at all.



However, after this excellent timing performance, I was disappointed to find that the current Midex 8 drivers are not multi-client, at least not when using the standard Windows MME driver interface. This won't bother everyone, but it will affect those musicians who want to run stand-alone synth editors alongside Cubase. Apparently the drivers are multi-client-capable when addressed by an application using DirectMusic drivers, but there are few professional music applications that do this.



Steinberg maintain that since the LTB aspect of Midex 8 is so closely linked to Cubase, it would be foolish to compromise its timing by adding multi-client capability. I'm sure many musicians will agree with their priorities, but reading between the lines I suspect Steinberg may still manage this with a future driver release. Let's hope so, since Emagic seem to offer this with their AMT8, and the only alternative for those using dedicated synth editors such as MIDI Quest, Sound Diver, or XGedit is to return to Steinberg's Mixer Maps -- not much of a comparison!



Some of you may already be thinking that you could just install a utility like Hubi's Loopback to add multi-client capability, much as we have done in the past with other interfaces. Unfortunately you will lose LTB support in the process -- only when Cubase talks directly to the Midex 8 drivers do you get the improved timing.



Conclusions



With VST Instruments now offering sample-accurate playback timing, musicians with hardware MIDI synths are becoming the poor relations, at least as far as timing is concerned. Steinberg's Midex 8 changes all that for Cubase and Nuendo users, but do remember that although it will work fine as a standard MME interface with other music applications, the advantages of LTB timing will be completely lost.



I was impressed by the improvements I measured in MIDI timing, and those with large MIDI rigs requiring lots of ports will benefit even more. However, as mentioned earlier, PC owners will need to run Windows ME if they want to use more than one Midex 8, due to current WDM driver restrictions. Some people will be disappointed at the lack of a stand-alone patchbay facility, but once Cubase is up and running there's little you can't duplicate. Sadly, I suspect more people will be upset by the current lack of multi-client drivers, and anyone currently running a stand-alone synth editor alongside Cubase will have to discard it to use the Midex 8.



However, tighter timing is obviously the most important design goal here, and Steinberg have certainly achieved it. If you use Cubase VST 5.0 or Nuendo 1.5 and want an eight-in/eight-out MIDI interface that will give you the tightest timing available, this is currently the only option.  
Published in SOS May 2001