TI 8mx2 Preamp / Mixer

PLEASE NOTE: This article has been archived. It first appeared on ProRec.com in July 2000, contributed by then Editor-in-Chief Rip Rowan. We will not be making any updates to the article. Please visit the home page for our latest content. Thank you!

Audio-Toys, Inc. (ATI) made a name for itself in the past decade with its series of Paragon mixers, which have earned high marks as monitor and broadcast mixers. With the 8MX2, ATI is earning high marks for its mic preamps.

The 8MX2 was apparently designed primarily to be a front-end system to an DA-88: it has 8 mic inputs, feeding a single DB25 output jack. The 8MX2 provides limiters on every channel, making it an ideal candidate for a live remote rig. Additionally, the 8MX2 offers some limited mixer capability, rounding out its usefulness as a front-end to an 8-channel digital tape machine.

The front panel controls are fairly straightforward. Each channel has a pair of dual knobs which control input gain, limiter threshold, mix level, and mix pan. Switches are available on each channel for phase and phantom power. Another pair of switches control the mixer input selection and cueing selection.

It’s easiest to understand the functionality by separating the mic preamp controls from the mixer. As a straight-ahead mic preamp, each channel gives you phantom power, a phase switch, a gain knob, and a limiter threshold knob. The knobs are 41-position detented, giving you precise control and letting you easily match the gain and limiter settings of several channels. Easy enough.

Each channel also allows you to feed a two-channel mix bus from either the mic preamp or your multitrack. The channel gives you level and pan controls for the feed to the mix bus (think of the pan and fader on your mixer). Switches are provided to send the track to a cue bus, like a channel solo.

On the far right of the unit are a pair of meters for output level and limiter gain reduction. A variety of combinations of output level can be monitored: the output of the mix bus, or any single channel, pre or post limiter. The gain reduction meter shows the amount of limiting on any soloed channel. A headphone jack is provided along with a monitor level control. In the end, you can use the 8MX2 to replace your mixer in your rack, provided you just use the mixer for light-duty monitoring use. It makes the 8MX2 an ideal front end for “mixerless” DAW systems.

The unit sports decent measurements. The unit offers a good portion of usable gain (+64 dB) and low noise (-132 dB e.i.n), giving it plenty of dynamic range. Frequency response is 10 Hz – 50 KHz +/- 1 dB.

Road Test

I had the opportunity to use the 8MX2 on a CD project I recorded in November of 2002, and enjoyed every minute of it.

Sonically, the 8MX2 is somewhere between “colored” and “colorless”: it definitely has a sound of its own, but that sound is hardly “effected”. Rather, it recalls classic board preamps – just slightly boxy, barely warm, ever-so-slightly rolled-off on the highs and lows, and just a little forward. If you listened to it on its own without any frame of reference you might not even pick up on these characteristics. They are very subtle, and generally speaking, very pleasant. The sound is not fatiguing. I could use the 8MX2 on just about anything from kick drums to horns and love it.

I loved the sound of the 8MX2 on electric guitars – use used it with a variety of amps including Vox, Marshall, Rocket, and Clark amps, with mics including SM57s, AT4050s, GT AM40 and MD1a, and others, and in every case the sound of the 8MX2 flattered the amp and mic. The sound had great presence and focus, and seemed to stay put in the mix. We also used the 8MX2 on drum overheads, which really benefitted from the subtle presence boost, as did kick and snare drum. The 8MX2’s gain control goes from 0 dB to +64 dB. The availability of a 0 dB setting virtually eliminates the need for a pad, an unexpected convenience.

In practice, I found myself not using the limiters much. Back in the days of 16-bit recording, where every bit was precious, the idea of running super-hot and using limiters made more sense than it does these days, with 24 bit converters sporting 120 dB of dynamic range. The limiters are super-fast brickwalls, and do work well to absolutely prevent digital overs, but their sound is fairly harsh. Used in moderation as failsafes, the limiters serve their purpose very well: they prevent a keeper take from being ruined when some freak transient threatens to splat the converters. In at least one application the limiters absolutely saved the day as we tracked a very dynamic song and the drummer just lost his mind at the end of the track.

Unusual Quirks

The unit has some curious quirks. The printing on the face, while easy to see, is strangely laid-out, with numbers and labels seeming out of place and crammed around the knobs. The mixer routing is somewhat confusing at first, and the sparse block diagram in the manual did not help much. I found myself just hooking stuff up to the 8MX2 and pressing buttons to figure out what everything did.

The high-voltage design of the 8MX2 means that it runs hot. To combat the heat, the designers employed a micro fan in the back of the unit. In most situations the fan should not be an issue, however, if you use your control area to record, or if you record in a common area, the fan noise could be a concern. In our application, we were tracking in a single large room, but were able to control the noise from the 8MX2 by using some baffles. Generally speaking, though, I don’t like fans near me when recording. I would have preferred a no-fans design.

Finally, the 8MX2 only has a single DB25 output connector. No 1/4″ outputs are provided. While this is surely a great convenience for use with a DA-88, it will require most users to purchase (or build) a fanout connector. In my opinion, for a unit with a $3000 list price, the $50 1/4″ fanout should have been included in the package. But enough about me.

Mixerless DAW?

Functionally, what intrigued me most about the 8MX2 was the ability to use it as a simple mixer. These days, I pretty much only use my mixer as a volume knob on my DAW’s output. All the mixing and routing happens in the DAW. With the 8MX2 I was able to put my old mixer to rest. By routing the DAW’s output to a pair of less-used inputs (7 & 8), I was able to monitor those channels through the 8MX2 while using the mic preamps to record. The only thing you cannot do is mix a channel’s mic input with the machine return. In other words, you can either monitor the mic, or the return. This is not an inconvenience to me, since the only time I’m likely to be using all 8 channels of the 8MX2 is when I’m recording the starter rhythm tracks and there isn’t anything coming out of the DAW to be monitored.

Be forewarned, though. The 8MX2 is not a full-featured mixer. There are no aux sends, or multiple busses, or EQs. Before you decide to “go mixerless” with the 8MX2, you really need to decide if you can live without those other features.

American Ingenuity: Comprehensive Answers
Bill Park

The ATI 8MX2 is a uniquely configured box. Using the popular mic pre from the Paragon console should be recommendation enough, but the folks at ATI have looked into the market place and tried to provide a high quality option for the recordist who requires a large degree of flexibility in a small space. It was designed for MDM/DAW usage, with a very cool routing structure, which I will explain in a moment.

Each of the 8 channels has the following switches: Cue, Phase Reverse, Assign to Mix, and Channel/Return Select. The channel level control is a dual concentric setup, with the Pan being the outside control. The inner Mix Level knob is not a conventional pot, it is a 41 position control. Why? Repeatability. The outer portion of the second dual concentric control sets the limiter Threshold, while the inner knob, also a 41 position control, sets the channel Gain.

That’s a lot of power. And here is what I think is the really cool part: Each channel has direct outputs and machine return inputs. You can feed a recorder, and monitor the returning signal. You can assign any or all 8 channels or their machine returns to the Mix, and from the Master section mix to 2 track.

The Master section is equally simple yet powerful. There is a ten-segment meter to read limiter Attenuation of cued channels and a ten-segment meter to read the selected Level. There is another dual concentric control, this one handling Left and Right Mix Master Pan and Mix Master Level. There is a headphone output jack and a Monitor Level control. Selecting between the monitored signals is accomplished by the use of three switches.

The Mix Return switch sends the input from the 2 Track Return TSR jacks to the Monitor section when pressed. The 2 Track Return TSR jacks are located on the rear panel.

If the Pre switch is in the ‘up’ position, the signal sent to the monitor section is the Channel Output of the cued Channel/s. If the Pre switch is pressed in, the monitored signal will be the Channel Input of the cued Channel/s.

The Ret switch sends the Return signals of any cued Channels to the monitor section.

Monitored signals show up at the headphone jack, on the appropriate meter, and at the left and right TSR Monitor Output jacks on the rear panel.

The rear panel also contains the 8 XLR inputs, phantom power and ground lift switches for each channel, and the TSR left and right Mix Output jacks. There is a D-sub connector for the 8 channels of Direct Output, and a D-sub for machine control. The pinout of these D-subs conforms to the Tascam standard.

And there are two 9 pin D-subs. These connection points allow one to stack and interconnect multiple 8MX2 units, allowing one to be the master, and having cue functions follow through multiple units. This also provides similar control access for compatible consoles and other units using the same communication protocol. And gee whiz, we’re talking about an amazing, eye-straining, finger scrunching 73 controls in one rack space, though to be fair these are spread among 8 channels and a master section.

The ATI 8MX2 exhibited plenty of character without descending into the fuzz-box realm of many inexpensive so-called “Microphone Pre-Amplifiers”. The ATI 8MX2 retains the highs, but the lows and mids were fuller and richer than either the John Hardy M1 or the Midas XL-42.

Conclusions

The 8MX2 is a flexible, great sounding unit that is one part mic pre, one part mixer. It is one of the best conceived packages of functionality available for the digital recordist: great preamps, brickwall limiters, lots of gain, and a very usable, if simple mix bus. It is no mean feat to stuff all of this functionality into a 1U container, and ATI deserves credit for building a very portable, usable piece of gear. With the 8MX2 and an 8 I/O DAW with flexible routing, it is quite conceivable that one could build a completely mixerless, highly functional DAW with a total “face space” of 2U.

At a list price of $3000 the 8MX2 comes in at about $350/channel. That’s a great price considering the quality of the preamps and the other great functions available int he mixer section. If you are interested in building a mixerless DAW, the 8MX2 might very well be your Holy Grail. And if you just want to add a great-sounding 8-pack of mic preamps, this unit is definitely worth your time.

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