FIG. 1: The ATB Series mixers come in three configurations: 16, 24, and 32 channel. The 16-channel model is shown here.
Malcolm Toft has played an integral role in the creation of a number of important and interesting products over the last 40 years. He's best known as the founder and chief design engineer of Trident Audio, the manufacturer of legendary consoles such as the A Range and the 80B. He later designed another large-format analog desk, the now-defunct MTA 980 series, along with some rackmount gear, all of which was reminiscent of his most famous products.
His latest venture, Toft Audio Designs, has produced a board that is unique in the current audio market. The ultracompact ATB Series 8-bus console is available in 16-, 24-, and 32-channel configurations, which are identical featurewise except for the number of input channels. Its feature set is topflight, and its footprint is remarkably small considering its comprehensive functionality. I reviewed the 16-channel ATB 16 (see Fig. 1).
When it comes to low-cost, compact analog mixing boards, the 800-pound gorilla is the Mackie 8-Bus, along with the competitors that were quick to capitalize on its success. However, the ATB Series consoles are more closely aligned with the long-discontinued Soundcraft Ghost, a console that offered more channel strip and routing features than the Mackie does and had optional MIDI-based functions. Although the Toft mixer currently doesn't have MIDI or digital I/O, it does have a slot for a MIDI/digital I/O card, which should be available sometime in 2008. The ATB Series mixers set themselves apart from pretty much any other product in their price range in several aspects of their design, avoiding issues that have compromised other low-end consoles.
Cruising the Strip
I'll begin with a look at a single channel strip (see Fig. 2). Starting at the top, in the mic-pre section, you'll find buttons for +48V phantom power, input/monitor selection, line-level input selection, and phase reverse. An input gain knob provides 6 to 65 dB gain at the mic input. Next up is the EQ section, featuring four bands that each provide ±15 dB boost and cut. The high-frequency shelving filter can be set at either 8 or 12 kHz. High- and low-mid EQs can be swept from 1 to 15 kHz and from 100 Hz to 1.5 kHz, respectively. A low-frequency filter can be set at 60 or 120 Hz. There is a button to engage an 80 Hz highpass filter, and another to turn the EQ on or off.
Below the EQ controls are six aux sends; aux 1 is prefader, while auxes 2 through 6 can be switched between pre- and postfader. Further down is a monitor section that allows you to listen to a separate input signal, with a switch that lets you apply the channel's EQ if desired. This signal can also be sent out of aux sends 5 and 6. Directly above the fader is a pan knob along with solo and mute buttons for the channel, and the 100 mm fader is metal bodied. To the right of the fader are signal-presence and overload LEDs, and buttons for sending the signal to the main L/R output as well as to any of the eight buses.
In addition to a fader, pan knob, and solo button, each bus channel has its own 12-LED level meter and knobs for aux sends 5 and 6. Aux send 5 can be set pre- or postfader to a monitor-level control for each bus. This is handy for setting headphone mixes or effects sends from the bus section. An effects return level control and associated pan knob round out the bus strip. Possibly the coolest feature here is that the bus section can be soloed at the main outputs, and its level controlled with a dedicated knob.
On the back panel, each channel has mic and line inputs, a line-level direct output, an insert jack, and a monitor input. For the bus section, there are inserts, outputs, and monitor returns for each bus. The bus section also has stereo effects returns for each bus, which can be used as 16 extra inputs on mixdown. The master section allows for two sets of monitors to be connected, and it has main L/R stereo insert points in addition to 2-track return jacks and main outputs.
There are a couple of other notable features in the master section. One is the ability to route the talkback mic to either the auxes or the buses and master L/R outputs (lowering the output volume by 25 dB to avoid creating a feedback loop over the monitors). In addition, the headphone output has its own amplifier and level knob, so it functions independently of the main output amplifier (which surprisingly is not the case with the Ghost).
Oh, the Sound of It
FIG. 2: A look at the controls that make up an ATB Series mixer''s channel strip: (A) the preamp and EQ sections; (B) the aux and monitor sends; and (C) the fader and pan knob and the mute, solo, and bus assign switches.
The mic pres on the ATB Series mixers utilize Burr-Brown chips and sound clean and robust. To test them, I recorded several tracks of vocals, acoustic guitar, and drums. I used pairs of large- or small-condenser mics, with one of the pair going through the ATB and the other through the preamp of a Soundcraft Ghost or Mackie VLZ mixer (each about a decade old but both fairly comparable to the ATB Series mixers in relative price and feature set).
In each case, I had to crank the gain considerably more on the ATB than on the other board's preamp. This was even more pronounced when the comparison was with a preamp on an RME Fireface 800. Similarly, the outputs at every stage had noticeably less maximum output level than at similar stages on my Ghost; this applied to the channel direct outs, the individual bus outs, and the summed line and monitor outs. There wasn't any more noise on the ATB when I matched levels between it and the Ghost (though its THD spec is an order of magnitude greater than that of the Ghost or the Mackie), but the discrepancy was, at the very least, peculiar. Also, when listening to the channel's line input, the same gain knob is used to adjust input level: there is no separate “tape trim” knob, as is found on some consoles.
According to the documentation, the design of the equalization borrows heavily from that of the Trident 80B (“ATB” — get it?). The EQ settings are certainly well placed and sweet sounding; you can carve out some very nice tracks. I'm not sure whether there was an overwhelming desire on Toft's part to be faithful to the 80B design, but I would have appreciated Q knobs on the low- and high-mid EQ bands like on the original.
It's the Little Things
The ATB Series mixers benefit from a number of design choices that are very satisfying to those of us who have owned other consoles in this price range. First, instead of using a fan to cool the power supply as similar consoles do, the ATB models use a large toroidal transformer and a hefty heat sink. That means they're completely silent when in action, a boon to users without dedicated machine rooms. Second, the jack field is on the back (rather than on top as with many others), so unused inputs don't collect dust over time if you neglect to cover them.
Perhaps most important for the long haul of ownership, the ATB's modular construction allows 8-channel sections to be removed easily from the top of the unit, and ribbon cables aid further disconnection. Similar consoles are much more unforgiving in the event of a breakdown. Active components such as ICs are socketed for easy replacement (or even upgrade with different ICs of compatible spec), while passive components such as resistors and capacitors are through-hole rather than surface mounted, which makes the ATB infinitely more serviceable should a component fail or fall outside of specification over time. Instead of requiring the replacement of an entire channel strip, the failed component can be removed easily and a new one soldered into place.
ATB: All the Best
The ATB is a powerful mixer in a relatively small package. It has several features that I have encountered only on much more expensive mixers. Its small footprint does come at a slight ergonomic cost, as the knobs in the bus section are situated extremely close together. But it's not as if that's a high-traffic area of the board, and overall it's a small price to pay for all the benefits you get. There are a few other curious things, most notably the relatively low output level from the direct, bus, and main outs. Also, the cord that connects the mixer to its power supply is shorter than I would have expected. (Because the power supply is silent, this isn't quite as big an issue as it might otherwise be, because power-supply placement won't be as critical.)
But all in all, the ATB is built better from the ground up than anything else in its price range — its preamps and summing amplifier sound just fine. The EQ has lots of flexibility and is better than anything I've heard in a similar type of mixer (at least in those on the market now; the Ghost was close but it's no longer available new). Importantly, the ATB mixers are more readily serviceable than other mixers currently in their class. (As long as Toft has manufactured plenty of extra parts, that is — the way console manufacturers and models come and go, you never know how long the ATB will be in production.) The ATB Series mixers deliver, and I'm sure anybody who purchases one will agree.
Rich Wells runs the Supreme Reality (http://thesupremereality.org), a recording studio in Portland, Oregon.
TOFT AUDIO DESIGNS
analog mixing console
ATB 16, $3,999.99 (street)
ATB 24, $5,099.99 (street)
ATB 32, $6,499.99 (street)
FEATURES 5 EASE OF USE 4 AUDIO QUALITY 4 VALUE 4
RATING PRODUCTS FROM 1 TO 5
PROS: Comprehensive in both functionality and user adjustment. Great-sounding preamps. Modular construction. Excellent build quality. Power supply cooled silently — no fan noise. Sweet-sounding EQ.
CONS: Overly compact bus section. Some output levels lower than expected. No Q controls on low- and high-mid EQ bands.
Toft Audio Designs