Studio Technologies MODEL-81
1x8 Stereo Analog Audio Distribution Amplifier

MODEL-81

One Stereo Input
The differential input circuitry is compatible with balanced or unbalanced signals having a nominal level range of –12 dBV to +10 dBu. Laser trimmed, the inputs offer superior common-mode signal rejection. To achieve optimal audio performance the ExactCal calibration section matches the specific input levels with the Model 81’s internal gain structure. Two 15-turn trim potentiometers and four LEDs allow fast, precise calibration.

With ExactCal, excellent audio performance can be achieved with little or no hassle. During normal operation, the ExactCal LEDs also serve as convenient signal-present indicators. Standard 3-pin XLR-type connectors are used to interface the input sources with the input circuitry. Manufactured by Neutrik, the connectors feature metal housings for reliable operation.

Eight Stereo Outputs
The Model 81 contains eight independent stereo output sections. For compatibility with a wide range of facilities, each output section can be independently configured for a –10 dBV or +4 dBu nominal output level. Each output features an electronically balanced circuit capable of driving balanced or unbalanced loads. Short circuit resistant, the rugged output circuits can drive full signal levels into 600 ohm or greater loads.

The Model 81’s architecture precludes the need for individual output-level trim potentiometers. With the input signal calibrated using the ExactCal section, the eight outputs use 1%-tolerance components to provide precise –10 dBV or +4 dBu outputs. Two 25-pin D-subminiature connectors are used to interface the eight stereo outputs. Following the industry-standard connection scheme, the D-sub connectors allow fast, reliable, low-cost interconnection.

Audio Performance
The Model 81 is the result of exacting circuit design combined with the latest state-of-the-art components. Like all Studio Technologies products, the Model 81 has survived tough listening evaluations by industry professionals. These veterans have the "ears" to guide us in achieving the right performance. The outcome is a product that achieves sonic excellence.

Features:

• Stereo input with transformerless laser-trimmed circuitry
• ExactCal section allows precise input-level calibration
• 15-turn input trim potentiometers
• 3-pin Neutrik XLR-type input connectors
• Eight independent stereo outputs
• Configurable –10 dBV or +4 dBu nominal output levels
• 25-pin D-subminiature output connectors
• Inputs and outputs support balanced or unbalanced operation
• Internal ±17 V power supply with toroidal mains transformer
• Single rack-space mounting

Specifications:

• Audio Input: 1, stereo
  Type: electronically balanced, compatible with balanced or unbalanced signals
  Impedance: 24 k ohms
  Nominal Input Level:–12 dBV to +10 dBu
  Input Level Controls: 2, 15-turn trim potentiometers
• Audio Outputs: 8, stereo
  Type: electronically balanced, direct coupled
  Compatibility: intended to drive balanced or unbalanced loads of 600 ohms or greater
  Output Impedance: 50 ohms
  Nominal Output Level: –10dBV or +4 dBu, each output individually configurable
  Maximum Output Level:+27 dBu into 10k ohms, +26 dBu into 600 ohms
  Frequency Response: 10 Hz-70kHz +0/–0.5 dB (down 1 dB @ 110 kHz)
  Distortion (THD+N): 0.004%
  S/NRatio: 91 dB (20 Hz-20 kHz, ref. +4 dBu)
  Crosstalk: 75dB (1 kHz, ref. +4 dBu)
• Connectors:
  Audio Inputs: 2, 3-pin XLR-type, manufactured by Neutrik
  Audio Outputs: 2, 25-pin D-subminiature
  AC Mains: standard 3-blade IEC-type
• AC Mains Requirement: 100, 120, or 220/240 V, ±10%, factory configured, 50/60 Hz
• Dimensions (Overall):
  19.00 inches wide (48.3 cm)
  1.72 inches high(4.4 cm)
  6.65 inches deep (16.9 cm)
• Mounting: one space in a standard 19-inch rack
• Weight: 7.0 pounds (3.2 kg)

Our Part #  MODEL-81