VT-1 Single Channel Vacuum Tube Microphone Preamplifier

VT-Series Microphone Preamplifiers have long been the weapon of choice for top artists, engineers, producers, and other audio professionals. Designed to deliver unparalleled performance in ultra high-fidelity tracking sessions, any microphone or sound source will benefit from the improved clarity, definition, and lack of solid-state artifacts that are the hallmarks of the VT-Series.

In designing the VT Series Microphone Preamp, no compromise in sonic quality, reliability, or ruggedness was permitted. Like the best tube equipment of the 1950s and ’60s, each VT-1 preamp is hand-built on a heavy-gauge aluminum chassis, utilizing point-to-point wiring. Each and every vacuum tube is selected for minimum noise and microphonics, and to deliver maximum sonic clarity. The front panel switches control sealed, gold-contact precision relays for all audio switching, totally eliminating the possibility of dirty contacts degrading the sound quality while minimizing the internal audio path. Four class-A triode amplifier sections (in two tubes) in each channel comprise the entire active circuit. This elegantly simple circuit, expertly executed with top-quality components and careful design optimization, provides the sonic superiority that the VT-Series preamps have become known for.

Features
All vacuum-tube design
Lo-Z input position for superior performance with transformerless microphones
Phase (polarity) reverse switch
+48 volt phantom power (completely disconnected when off)
Custom-design Jensen input and output transformers
20 dB input pad (switchable)
True VU meters (amplifier isolated)
All point-to-point audio wiring
Gold input and output XLR connectors
Polypropylene and polystyrene coupling capacitors
All audio switching through gold-contact, sealed precision relays
International operation on 100, 120, or 220 VAC, 50/60 Hz
CE certified, RoHS-compliant
+4 dBm output
Conservatively rated precision components and rugged construction for stability and long life

Specifications
Input 150 ohms
Input Load Impedance 1.5k ohms
Minimum Input Level -65 dBm nominal
Maximum Input Level @ 20 cps -30 dBm without pad, -5 dBm with 20 dB pad
Gain 53 dB
Frequency Response +/-0.25 dB 20 cps to 20 kc; -3 dB @ 0.5 cps and 55 kc
THD+Noise less than 0.25% 20 cps to 20 kc
Intermodulation Distortion SMPTE less than 0.02%
Signal to Noise Ratio 74 dB minimum
Equivalent Input Noise -124 dBm maximum
Output low-Z, transformer-balanced
Maximum Output Level +22 dBm, 20k ohm load
Power Requirements 100, 120, or 220 VAC, 50/60 Hz
Dimensions 19” (48.26cm) W, 5.25” (13.34cm) H, 14” (35.56cm)