MACKIE MDB-1A ACTIVE DIRECT BOX

Product Highlights

• Connect an Instrument to a Mic Input
• Converts Unbalanced to Balanced
• Converts High Impedance to Low Impedance
• 1/4" Unbalanced Input
• 1/4" Thru Jack
• XLR Balanced Output
• Switchable Pad Prevents Overloading
• Ground-Lift Switch Minimizes Hum
• Merge, Low-Cut, and Polarity Switches
• Operates on Phantom Power

The alphaton Direct Injection-Box SM-50 allows direct connection of electric guitars,
electric bass, and electronic music instruments with mixing desks of PA systems
and of recording studios.
The SM-50 reduces the amount of microphones used on stage, thus improving gain
before feedback.
Coloration of sound is avoided. Clean signal without interference from other instruments
eases the job of the recording engineer. The use of a strong aluminium die-cast box allows
trouble-free function for a number of years even under adverse conditions. Double grounding
(hum) can be eliminated by activating the built-in ground-lift switch. Isolation voltage between
input and output is 2500 volts, against ground 1500 volts (with ground-lift switch activated).
The box thus complies with toughest safety standards.

Technical Data

input impedance 20 kOhm
input impedance, instrument input impedance, line-In input impedance, speaker output impedance 200 Ohm
frequency response 30 ... 20000 Hz, ± 1 dB
THD isolation voltage tranformer pri/sec 2500 V
                        outpur to ground 1500 V
inputs 1/4" phone jacks, unbalanced
outputs XLR, balanced, microphone level.
           pin 1 = ground, pin 2 = hot, pin 3 = cold
case aluminium die-cast
weight 230 g
dimensions113 x 71 x 37 mm
 

Passive DI box especially designed for guitars.

The PDI09 can be connected between an effect device or amplifier and the mixing console. The PDI09 is not suitable for direct connection to a guitar. Integrated filter circuits simulate the authentic "speaker" sound. Tone can be varied between "Mellow“, "Normal“, or "Bright“.

Technical specifications:

• Input: 6.3 mm jack with parallel "THRU" socket
• Output: male XLR transformer balanced
• Attenuator: (Level switch) 0 dB for line signals, -15 dB for small amps up to 10 w, 30 dB for large amps up to 200 w
• No battery necessary

Phantom or battery powered in a rugged steel chassis, with separate Speaker Level input connector
 
The ARX DI-PLUS represents another major step forward in active direct boxes. Packaged in
a single channel stand-alone format, the DI-PLUS represents a fresh look at active D.I. concepts.
Precision engineered
Ultra quiet, ultra clean circuitry delivers maximum headroom whatever the signal. Premium grade
components, plus an all-steel chassis gives excellent hum and noise specifications and superb
audio quality in a tough, roadworthy package.
Level control
The DI-PLUS features a Normal gain high impedance unbalanced input on the front panel, running to
a balanced XLR output on the rear. There is also a separate -40dB Speaker Level input for signal coming
from the External (auxiliary) speaker output of an amplifier. A a global Pad switch drops both the normal
input and the speaker input by a further 20dB, making it suitable for all applications, from the softest
keyboard to the hottest broadcast levels.
 
Battery compartment
The revolutionary simple 'clamshell' action of the DI-PLUS battery compartment makes battery changing
extremely easy, even on the darkest stages.
A 9v alkaline battery snaps into a PCB mounted battery holder for fast, secure location. No fragile battery
clip leads to break, no tools required, no screws to lose. Production crew heaven!
 
Automatic Phantom switching
The DI-PLUS will automatically switch itself to the console's own Phantom Power, if available, and an LED
will indicate this mode. Turn the Phantom Power off and it will instantly revert back to battery mode.
Rugged all-steel case
A lot of direct boxes are fitted into brittle cast alloy cases. Not this one! The tough all-steel inner and outer
chassis of the DI-PLUS provide excellent RF/EMF shielding while making it a sturdy, heavy duty unit that is
hard to dislodge, and hard to leave behind.
 
Rear panel showing XLR connector, ground lift switch, and captive screw for opening up the unit
for battery changing
 
Whether you're a Studio or Live Sound engineer, installation contractor, or broadcast engineer, you want all
the dynamics and clarity of the original sound source transferred to the mixing console. The ARX DI-PLUS
provides a rugged, no-compromise solution to all direct injection and signal balancing requirements.
 
T E C H N I C A L  S P E C I F I C A T I O N S:
Max Input Level
+13 dB Phantom powered
+6 dB Battery powered
Input Impedance 1 Meg Ohm
Max Output Level
+17 dB 10K Ohm load Phantom powered
+12 dB 10K Ohm load Battery powered
+11 dB 600 Ohm load Phantom powered
+12 dB 600 Ohm load Battery powered
Output Impedance 680 Ohms Balanced
Output Signal to Noise
-100 dB unweighted
-104 dB A weighted
Dynamic Range
117 dB 10K Ohm load Phantom powered
112 dB 10K Ohm load Battery powered
111 dB 600 Ohm load Phantom powered
107.5 dB 600 Ohm load Battery powered
Distortion
100 Hz .0027%, 1KHz .0028%, 10KHz .0037%
Frequency Response 20Hz to 20KHz, ± 0.2 dB
Gain through Unit: 6dB (Normal input, Pad switch out)
Pad Switch: -20 dB attenuation
Speaker Input
-40 dB attenuation, equivalent to 100:1 decrease in input level
-60 dB attenuation available with Pad switch
Input Connectors
Insulated jacks (!!!Note that the Input connector switches the unit on
when a plug is inserted. Remove plug when storing to avoid battery drain!!!)
Output Connector
3 pin XLR. Wired Pin 1 Ground, Pin 2 + Hot, Pin 3 - Cold.
With Audio Ground (Pin 1) lift switch
Construction
All-steel chassis, fibreglass PCB
Battery Access
Twist connector opens chassis, snap-in battery holder inside.
No tools required
 

You're serious about getting rid of all that excess noise on stage, but you've got so many line
instruments you don't know where to start. The ADB-4 from Stewart can take care of all your
high impedance problems. The ADB-4 is 4 active direct boxes, all in a module that only takes
up half a space on your keyboard rack. It's a rugged, durable piece of equipment that packs a
lot of DI power.

? Requires phantom power or 9v battery
? Ground lift switch
? Instrument or speaker level switch
? Transformerless
? Can be used with amp up to 400w
? RF shielding