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Studio Preamp - 

VT-737sp Tube Channel Strip

Studio Role: 

Fender Twin Reverb with the AKG 414, Reamping, Bass and Guitar DAW Direct In and Vocal/Dialog microphone DAW channel strip for the Neumann TLM-103





VT-737sp Tube Channel Strip

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Studio Role Description

The primary function of the Avalon VT-737sp channel strip is for Bass Guitar Direct DAW input.

When vocals or video dialog is required, it is a high-end condenser mic preamp channel for DAW recording.

It is also available for a Taylor acoustic guitar high-end condenser mic preamp channel or the Taylor and Seagull acoustic guitar DAW Direct input recording.

Device Details

The Avalon VT-737sp is a high-resolution vacuum tube triode channel strip design offering a Class A preamp with mic, DI, and line-level input selections; a minimum-signal-path opto-compressor with stereo linking; and a 4-band discrete, Class A passive-filter EQ with two sweepable, switchable-Q mid bands.

Avalon packed the VT-737sp with the fruits of their considerable engineering expertise: high-voltage circuits for generous headroom, a discrete internal toroidal transformer-coupled power supply, a soft-start tube life extension feature, a retro-cool oval VU meter for monitoring compressor gain reduction and output level, and more.

With its quiet -92dB noise floor, ultra-wide frequency response (10Hz-120kHz, -2.5dB), and impressive build quality (as evidenced by its sealed silver relays for signal routing), the Avalon VT-737sp is an audiophile-grade channel strip that will elevate your sound.

Avalon VT-737sp Channel Strip at a Glance:
• Class A preamp design with three input selections
• Opto-compressor with minimum signal path
• Sweepable EQ and hardwired bypass

Class A preamp design with three input selections:
The VT-737sp has three input selections:
1. It features a higher-performance microphone input transformer with 48-volt phantom selection.
2. The VT-737sp offers an instrument DI high-source input with a jack located on front panel.
3. The VT-737sp includes a balanced line input with discrete high-level Class A circuitry.

Other Key Features:
• The Class A preamplifier utilizes two cascaded dual vacuum tube triodes configured with minimum negative feedback.
• A high-gain switch boosts the overall gain of the preamplifier.
• The four high-quality tubes are configured as singled-ended anode coupled followers
• A passive/variable high-pass filter
• Hardwired relay bypass completing the VT-737sp's input signal conditioning
• A phase reverse relay is available on all three inputs

The Opto-compressor with minimum signal path:

The VT-737sp's opto-compressor features a minimum signal path design with twin Class A vacuum tube triodes for gain matching.
The optical attenuator acts as a simple passive level controller.

Full dynamic control from soft compression to hard- knee limiting can be achieved with:
• Threshold
• Ratio-compression
• Attack and release controls
• Gain reduction selection on the large VU meter.

Special spectral control, including de-essing, is available with the dual sweep mid EQ to side-chain switch.

The VT-737sp's EQ section can be flipped pre or post the opto-compressor via a front-panel switch for alternate effects and tone shaping.

Two VT-737sps can be linked via a rear panel link cable for stereo tracking.

The compressor bypass is a sealed silver relay for the most direct signal path.

Sweepable EQ and hardwired bypass:
The VT-737sp equalizer utilizes 100% discrete, Class A-high-voltage transistors for optimum sonic performance.

The high- and low-frequency bands provide the smooth characteristics of an all-passive design, while the dual mid bands include variable frequency and switched Q-width selection.

The enhanced range of the VT-737sp's mid bands is extended into the high and low bands by the use of X10 frequency multipliers.

The bypass switch also incorporates a sealed silver relay for the most direct signal path.

Dual sweep mid EQ to side-chain switch:
• The dual sweep mid frequency band controls are used to increase the mid frequency “Sensitivity” for the compressor’s threshold: De-essing for example
• The high-low EQ remains in the audio path for "tone enhancement” and is in the signal path
• The dual mid bands EQ settings only affect the Side Chain signal and is not in the signal path

The output amplifier utilizes another dual triode vacuum tube driving a 100% discrete, Class A, high-current, balanced and DC coupled low noise output amplifier.

The output level control provides a variable control of the overall signal path.

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