Studio Technologies Model 41 Interface with 4 Independent IFB Circuits

The Studio Technologies Model 41 is designed to create broadcast-standard IFB outputs from line-level audio sources. The unit's primary application is to interface analog outputs associated with digital matrix intercom systems with broadcast IFB user devices. The Model 41 creates four independent IFB outputs. Each IFB output provides DC power and two analog audio signals to support the connected IFB user devices. The Model 41's audio quality is excellent; little hiss, hum, or other artifacts are present. To ensure optimal operation, the unit provides resources for visually and audibly monitoring the audio output signals. In addition, the DC output voltage is monitored for fault conditions.

Key Features

• Transformer-coupled inputs
• Excellent audio quality
• Superior power-feed performance
• Four independent IFB circuits
• Single rack-space mounting
• Universal mains input powering

Technical Specifications

General Audio
Frequency Response - Pin 2 Output (DC with Channel 1 Audio)
+0/-3 dB, 20 Hz-20 kHz; +0/-1 dB, 100 Hz-20 kHz
Frequency Response - Pin 3 Output (Channel 2 Audio)
+0/-3 dB, 20 Hz-20 kHz; +0/-1 dB, 100 Hz-20 kHz
Distortion (THD+N) - Pin 2 Output (DC with Channel 1 Audio)
0.05%, measured at 1 kHz, +4 dBu
S/N Ratio - Pin 2 Output (DC with Channel 1 Audio)
86 dB, ref +4 dBu out, A-weighted
Audio Inputs
8, organized as four 2-channel inputs
Type
transformer balanced, capacitor coupled, compatible with balanced or unbalanced sources
Impedance
10 k ohms, nominal
Nominal Level
+4 dBu
IFB Circuits
4
Type
DC power with two channels of unbalanced audio (“wet” IFB)
Connections
Pin 1
common
Pin 2
30 Vdc (nominal) modulated with channel 1 audio (-10 dBu nominal)
Pin 3
channel 2 audio (-10 dBu nominal)
Maximum Audio Output Level
Pin 2
+9 dBu with +23 dBu on audio input
Pin 3
+14 dBu with +28 dBu on audio input
DC Current Output
220 mA maximum
Monitor Section - Headphone Output
Type
2-channel (stereo), drives headphones by way of 100-ohm series resistors
Compatibility
intended for connection to headphones with impedance of 100 ohms or greater
Maximum Voltage
8 Vpp, 100-ohm load
Monitor Section - Output Voltage Detection
Measures DC voltage level directly on pin 2 of IFB output connectors. Status LEDs flash when level is less than approximately 24 Vdc.
Connectors
Audio Inputs
25-pin female D-subminiature, 4-40 threads on locking hardware (two places)
IFB Outputs
3-pin male XLR
Headphone Output
1/4-inch 3-conductor phone jack
AC Mains
3-blade, IEC 320 C14 (mates with IEC 320 C13 connector)
AC Mains Requirement
100-240 V (±10%), 50/60 Hz, 40 watts maximum