ALPHATON SM-50 PASSIVE D.I-BOX WITH GROUNDLIFT

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
 

Tube-buffered DI-Box DI-1000

The Tube-Buffered DI-Box DI-1000 allows the extraction of all the musical details of
musical interfaces without degrading the sound. This can only be achieved by
providing a very high input impedance to avoid any loading of instrument pickups.This
design approach allows seemingly infinite headroom to preserve the real dynamic range
of the interfaced instruments.A vacuum tube enables all these goals to be achieved
without any compromises in sound quality.The sonic difference between a standard
DI-Box and the Tube-Buffered DI-Box is comparable to the musical resolution difference
between a standard microphone and a studio microphone.One of the best transformers,
the very transparent sounding JENSEN JT-DB-E, was chosen providing complete ground
isolation. The parameters of this transformer, like frequency response, phase response,
group delay and geadroom capabilities, play a vital part in the performance of this DI-Box.
 
Technical Specifications
Input
The signal of the instrument is directly fed to the tube circuit with > 20 MOhms input
impedance to prevent any signal degradation, inevitable in traditional designs.
Buffered Output“
The second stage of the vacuum tube is used to buffer the signal and lower the output
impedance to < 8 kOhms. This unity gain output allows for cable runs of 10 meters
without loosing high frequency information.
Boost circuit
The boost circuit increases the signal send to the output transformer by 15 dB. This may
be useful for instruments with extremely low output, but decreases headroom capability
to 6 Volt rms. Under these circumstances the signal may be clipped, concerning the output
transformer?s signal, which gives you 2nd harmonic tube-like distortion. This distortion
normally does not occur - but is sometimes desirable, being the reason for this special feature.
Unity circuit
The unity circuit feeds a low distortion unity gain signal to the JENSEN output transformer.
This gives the best possible sound quality.
Ground-lift“-Switch
This front panel mounted switch allows complete ground and electrical isolation between the
direct injection box and the console or recording device.
 

Mechanical Specifications
Cabinet 2 mm stainless steel
Front- and rear-panel 1,5 mm stainless steel lasercut and photo-chemically etched
Dimensions 185 x 100 x 40 mm
Vibration insulation 4 high-compliance rubber-elements
Operating Voltage
220/110 V AC, selectable via rear panel mounted switch. The fuse is easily
accessible from the rear panel. IEC mains connector with optional fixture.
Construction details
Double sided glass fibre contacted PCB with 70 mm copper plating. 1% metal film resistors
and the finest polypropylene capacitors are used in the signal path. MIL type Switchcraft jacks
and high performance switches ensure flawless operation. The power supply is optimised via
measurement quality toroid transformer and a low impedance design to ensure the lowest
possible noise. Through a double sided PCB all parts are roadworthy secured. A waterclear
blue LED perfects the aesthetics of the DI box.

Technical Data
Input impedance > 20 MOhm
Output impedance180 Ohm at 1 kHz
Frequncy response 20 Hz - 20 kHz (-0,1 dB)
                             5 Hz - 120 kHz (-3 dB)
THD at 0 dBv  0,06% at 20 Hz
                      0,04% at 1 kHz
                      0,035% at 20 kHz
Signal to Noise Ratio 86 dB
Tube ECC 83/7025 A - military E 83 CC optional
Output transformer JENSEN JT-DB-E
Polarity Pin 2 Hot , AES/IEC -Standard
Max. Input voltage > 30 V peak
 

Passive DI box. Jack input with paralell "THRU" output, transformer balanced XLR output. Attenuable input sensitivity, can handle both line level and speaker level signals.

At dbx, when we do something, we do it right. So when we decided to create our new direct injection boxes, we didnʼt settle for the same old tired approach to direct box design. With our dbx name on the line, how could we? One look at our new dB10 Passive and dB12 Active direct boxes will tell you that these are clearly different. With their bullet-proof construction, and extraordinary audio performance to rival their looks, finally thereʼs a direct box worthy of the dbx name.

Utilizing custom dbx mu-metal-shielded audio transformers, high-quality Neutrik® connectors, and low-noise circuitry preserves the sonic integrity and true characteristics of the signal source. Both boxes include a pad switch that accomodates instrument, line and even speaker level signals. Take even more control of your sound by utilizing the polarity invert switch to set the phase relationship between the direct and mic'd sound.

As a professional, you donʼt have time for interference, so weʼve included a ground lift switch to solve potential hum and buzz problems due to ground loops. And between the combined shielding of the cast metal chassis and the custom-wound transformer, you can be doubly assured of a clean signal free from interference. All of this sits atop a solid, stable footprint, that will keep the box from being dragged around the stage, and the unique contoured underside allows secure stacking of multiple units.

So whether you need to control the level, placement in the mix, or overall characteristics of 4 independent signals or control the gain leveling on a couple of stereo pairs, the dbx dB12 is for you.

• Phantom Powered
• Green LED Phantom Power Indicator
• +48V Phantom Operation
• Low-Noise Active Circuitr

Input: 1 instrument/line/speaker level

Connector: 1/4" jack

Type: Unbalanced, RF filtered

Impedance: 150k Ohm typical

Max Input Level: +20dBu (0dB pad)
+40dBu (20dB pad)
+60dBu (40dB pad)

Thru Output: 1 parallel connection from input jack

Connector: 1/4" jack

Type: Unbalanced, RF filtered

Main Output: 1 line level

Connector: XLR male jack

Type: Balanced

Impedance: 150 Ohm typical

Max Output Level: 0dBu

Transformer: Custom dbx mu-metal-shielded

Frequency Response: 20Hz to 20kHz, +/-2.5dB

Noise:

THD:

Dimensions: 5.82" L X 5.44" W X 2.20" H (148 x 138 x 56mm)

Weight: 1.4 lbs / 0.65 kg

Note: Specifications subject to change without notice.

Phantom or battery powered in a rugged steel chassis
 
The ARX DI-PLUS 2 represents another major step forward in active direct boxes. Packaged in
a single channel stand-alone format, the DI-PLUS 2 represents a fresh look at active stereo
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. Accurate Left and Right channel level matching keeps
the stereo image centred.

Level control
The DI-PLUS 2 features two high impedance unbalanced inputs on the front panel, running to balanced
XLR outputs on the rear. A a global Pad switch drops inputs by 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 2 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 2 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 2 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 Left and Right XLR connectors, ground lift switch, battery check switch and LED, plus
phantom power On LED 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,clarity and stereo information of the original sound source transferred to the mixing console.
The ARX DI-PLUS 2 provides a rugged, no-compromise solution to all stereo 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
+12 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 .0018%, 1KHz .0028%, 10KHz .0056%
Frequency Response 20Hz to 20KHz, ± 0.2 dB
Gain through Unit: 6dB (Pad switch out)
Pad Switch: Global -20 dB attenuation
Input and Loop Out Connectors
Insulated jacks (!!!Note that Channel A Input connector switches the unit on
when a plug is inserted. Remove plug when storing to avoid battery drain!!!)
Output Connectors
3 pin XLR. Wired Pin 1 Ground, Pin 2 + Hot, Pin 3 - Cold.
Global 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

• Compact, high-performance passive direct box
• Jack input 1/4" TS in and parallel out
• Gold-plated XLR output / impedance balanced
• Super-flat frequency output for uncolored sound
• Switchable filter that optimizes the DI for guitars
• Instrument/Amp switch lowers the input level 30dB for feeding amplifiers into the DI
• Instruments or amplifier outputs with up to 3,000 watts can be connected directly
• Offers impedance and signal matching of instruments to mixers
• Perfect for stage and studio use
• Ground lift switch eliminates typical ground loop problems
• Rugged metal case can take the rigors of the road

• Type: Passive DI Box
• Channels: 1
• Ground Lift: Yes
• Inputs: 1 x 1/4"
• Outputs: 1 x 1/4“, 1 x XLR
• Height: 1.4"
• Width: 3.75"
• Depth: 5"
• Weight: 0.66 lbs.
• Manufacturer Part Number: DI600P