Toa D-901 User manual

D-901 Rackmount Main Unit
MANUFACTURER SPECIFICATIONS
Frequency Response: 20–20,000Hz (±1dB) (±4dB
input)
Parametric Equalizer: 20–20,000Hz, ±15dB,
Q: 0.267–69.249
Filters: High-pass, ow-pass, notch, a -pass,
high- and ow-she f, horn EQ
Crossover Filter: Se ectab e between 20–20,000Hz,
s opes; 6dB/oct, 12dB/oct, 18 dB/oct, 24dB/oct
Compressor Threshold: –20dB to +20dB, 1dB steps
Ratio: 1:1, 2:1, 3:1, 4:1, 8:1, 12:1, 20:1, ∞:1
Attack Time: 0.2ms-5 seconds
Release Time: 10ms-5 seconds
Gain: –∞ to +10dB
Delay Time: 0–682.6ms, 0.021ms steps
Preset emory: 16
Auxiliary Function: System ock capabi ity
Control: RS232C D-sub connector (9-pin); optiona
remote contro modu e (D-981)
Dimensions (WxHxD): 482.6mm x 132.6mm x 320mm
Weight: 15.2 bs.
Accessories: Power cord x 1, rack-mounting screw x 4,
rack-mounting brackets x 2 (comes insta ed on the
main unit)
Design A
Performance A-
Value A
Final Grade A
GRADES AT A
GLANCE
TOA D-901
TOA'S LATEST entry into the AV and commercial sound mixer market, the D-901, packs a lot of
digital signal processing (DSP) power into a compact unit. They’ve taken all the functionality of today's
small-format digital mixing consoles, including parametric EQ and dynamics on every channel, digital
filters, and feedback control, and packaged it into three standard rackspaces. Fundamentally, it’s a 12-
input, eight-buss, and eight-output digital mixer with a comprehensive set of DSP functions, a
cross-point matrix, and optional cards for audio input and output.
Design
The D-901 takes a page from small-format mixing consoles with its Spartan front panel, where all
functions are adjustable using a common set of buttons and multiple menu pages. The panel is divided
into three sections, with the entry section taking the leftmost portion. This section has four buttons for
navigating menus, a parameter knob, and dedicated buttons for accessing utilities and saving presets.
Preset recall buttons provide access to the first eight of 16 total presets; accessing the other eight require
the inconvenient use of the knob and backlit LCD display. The center section of the front panel is
devoted to controlling the 12 inputs via select buttons and a rotary level knob, while the right section is
home to an eight-segment LED output meter, eight-output select buttons, and an output level knob. The
level knobs are continuous rotary encoders with surrounding LEDs that indicate the current setting.
The rear panel consists of eight slots for audio input and output cards, plus one slot for an optional
serial control card that interfaces to AMX and Crestron control systems, and a serial port for connecting
the mixer to a PC. TOA offers several different versions of analog audio input and output modules, with
onboard 20- or 24-bit A/D and D/A converters. Customers will appreciate being able to buy only the
inputs and outputs they need for a specific application.
TOA provides D-901 control software as a free download from its website, and this greatly simplifies
preset programming. It runs on modest PCs under Windows 98SE, ME, 2000, or XP, and connects to a
D-901 via a DB9 serial cable (not included). When launched, all the functions of the mixer become vis-
ible as part of an informative, onscreen block diagram. Clicking on any block reveals its settings in the
pane below, where adjustments are simple and intuitive. The control software is well written, easy-to-
use, and makes the setup process quick and enjoyable.
Design Grade: A
Performance
The review unit was shipped with four modules: a two-channel, XLR-equipped input card, a four-stereo
channel input card, a four-channel XLR output card, and a four-stereo channel RCA output card. Because
there are a total of eight outputs in the mixer, I alternated between the XLR and RCA cards for outputs.
I tested the D-901 in a large multimedia hall at a university, where it replaced a conventional analog mix-
ing console. With music, the D-901 provided a more accurate and open-sounding high-frequency response
than the existing mixer, and was on par with other digital mixers I’ve used. The EQ was transparent and the
level compressors were competent, although they have a sterile quality common to most digital mixers.
Once presets were stored, it was convenient to make small level adjustments using the channel select but-
tons and level knobs. The microphone preamplifiers on the two-channel XLR cards are clean and
uncolored, although I had to boost the gain substantially on one wireless microphone with a low output.
I also exercised the automatic microphone mixing, which operates on the principle of Number of Open
Microphones (NOM). In this mode, each time a channel’s gate opens, the D-901 recognizes it as an open
REVIEWS
Product: TOA D-901 digital mixer
Price: $2,190 MSRP (modules are $158 - $282 each)
Company website: www.toaelectron cs.com
Plus: H ghly flex ble, compact, good sound qual ty
Minus: D ff cult to program w thout free PC software
Final Grade: A
TOA D-901
Steve Cunningham is a 25-year
veteran of the pro audio
industry, and is on the faculty at
the University of Southern
California, where he lectures on
digital audio technology. Contact
him at [email protected].
by Steve Cunningham
2 FEBRUARY 200 proavmagazine.com
mic and adjusts the gain each time the number of
open microphones doubles by an amount set as a
preference. It worked as advertised.
The D-901 comes with a five-year warranty,
and based on its solid construction, there’s little
reason to believe the warranty will see much
action. I contacted customer support to trou-
bleshoot the PC-to-mixer connection, and
although I ended up in voicemail, my call was
returned within the hour by a polite tech who
suggested that my serial cable might be dodgy
(which it was).
You’ll get to know the entry section of the
front panel well when you set up presets in the
D-901 as you select channels and tweak them.
Combine this with the multiple-page menu
nature of the display, and the programming
experience becomes tedious. (I suggest you
bring a laptop and a serial cable to the job to
program the D-901). That aside, this unit
deserves high marks for performance. An
Ethernet connection to the PC would be even
more convenient than the serial connection, but
what's there works well enough.
Performance Grade: A-
Value
TOA has a history of success in commercial
sound, and the D-901 is a worthy addition to its
product line. At $2,190 plus cards, a likely price for
a complete D-901 might be around $2,700. This is
just slightly higher than current digital mixing
consoles with comparable interconnections, and
those units lack the D-901’s space-saving, anti-
feedback, and preset-locking features.
Value Grade: A