Tube Works MosValve 3175 Series User Manual

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Congratulations on purchasing the most innovative, unique and best-performing bass amp in existence.
With world-renowned and patented MosValve Circuitry for power coupled with an extremely versatile
bass pre-amp, your new bass amp is truly a major advance in the art of bass amplification. Please take
some time to fully familiarize yourself with the many design features of your new amp. It far exceeds the
performance level and design features of any similarly priced alternative equipment.
IMPORTANT FEAT URES
Conservatively rated 160-Watt or 300-Watt MosValve power output at 2 ohms. A 2 ohm rating was se-
lected by the designer, BK Butler to be the most versatile choice for bassists, enabling a vast array of
cabinet combinations to be used.
F.E.T. or TUBE preamp operation. For those perfectionists who savor the warmth of tubes, this amp will
satisfy you fully. For the ultimate in clean, punchy and accurate bass sound production, the alternative F.
E.T. preamp stage is also available.
Simplicity of layout and design provides the most reliability possible. For the example, the MosValve
power amplifier section contains up to 60% fewer parts than conventional amplifiers, but has vastly im-
proved performance and sound. Fewer parts means increased reliability, and a more direct, noise-free
tone.
Completely original and unique "dynamic response" limiter. You will notice that this limiter is not the
"brick wall" type that you may have experienced in the past. Much more like the old classic tube limiters
used in studios for years, your amp will give you great dynamic punch and response even with high set-
ting of limiting. Much time and input from bassists has resulted in perhaps the best single-knob limiter
ever designed.
5-control E.Q. section — The ranges and frequencies of these controls have been carefully selected to
be the most useful available. The E.Q. section is a combination of active and passive designs.
2 Direct balanced outputs — One is a buffered true-balanced Direct Out from the guitar without any gain
or E.Q. added. The other is selectable to include the preamp F.E.T. or tube plus input volume setting, or
the entire preamp plus E.Q. and Effects Loop.
Front-panel variable mixing of effects return. This feature greatly enhances the versatility of the tonality
available with effects.
Variable send-receive effects loop. Easily adjusts to virtually any signal level of floor or rack-mount device
on the market regardless of input/output level or impedance.
Standard rugged ozite covered all-plywood enclosures for exceptionally long life and good acoustical iso-
lation properties.
Take a few moments more and read the rest of the information. Again, please accept our thanks and
appreciation for your purchase.
MosValve™
REAL TUBE
3300 SERIES & 3175 BASS AMPS
OWNER’S MANUAL

Tube Works MosValve 3175 Series Specifications

General

Brand	Tube Works
Model	MosValve 3175 Series
Category	Amplifier
Language	English

Summary

Important Features of the MosValve Amplifier

Front Panel Controls Overview

Tube or FET Preamp Selection

Selects either TUBE or F.E.T. preamp for desired tone and response.

Input Jacks

Two inputs (+6dB and 0dB) for varying instrument sensitivity and summing capabilities.

Volume Control

Adjusts gain through the input preamp stage.

Limiter Functionality

Manages signal levels to prevent excessive bottoming and maintain dynamic response.

Contour Control

Shapes the overall bass-response slope across active bass frequencies.

Low Frequency EQ

Controls and shelves frequencies in the extreme low-end (150Hz and less).

Low-Mid Frequency EQ

Adjusts frequencies between 100Hz and 400Hz.

Mid Frequency EQ

Wide-range control for frequencies between 400Hz and 1500Hz.

High Frequency EQ

Shelves and controls frequencies 1500Hz and higher.

Master Volume

Controls input gain to the power amp section for overall output.

Effects Mix Control

Blends the effects return signal with the dry preamp signal.

Power Switch

Controls AC main power to the amplifier.

Rear Panel Connections and Features

Fuse Holder

Specifies fuse types for 120V and 240V operation, advising factory contact for wiring changes.

Line Out

Useful for 'slaving' amps or sending the full amp sound to a mixing board.

Speaker Outputs

Connects cabinets, requiring a minimum combined impedance of 2 ohms.

Limiter Cancel Jack

Allows footswitch operation to cancel the limiter's effect.

Effects Loop

Provides flexibility for connecting external effects processors.

Pre EQ/Post Loop Switch

Selects output mode for the balanced connector: preamp only or full signal path.

Direct Out

Provides a true balanced output for direct connection to boards or long snakes.

Safety and Operation Guidelines

Speaker Impedance Warning

Advises using speakers with ample power handling capability and proper impedance.

General Safety Precautions

Emphasizes reading safety information and using qualified personnel for servicing.

Using the Effects Loop

Operational Notes and Maintenance

Amplifier Operation

Designed for musical amplification, adding warmth and definition.

Speaker Usage

Recommends speakers rated at 125% of amp's RMS power; manufacturer not liable for speaker failure.

Heat and Ventilation

Normal heat presence; avoid obstructing vents for proper airflow.

Speaker Load Restrictions

Never load speaker outputs with less than 2 ohm loads.

Product Warranty Information