Benchmark LA4 - Black

The LA4 line-level preamplifier features the best analog volume control system available at any price.

At each volume setting, relays select pairs of high-precision resistors to attenuate the music to the desired level. This system eliminates the noise, distortion, and L/R balance issues found in more conventional analog volume control systems. Traditional potentiometers and integrated electronic volume controls are the weakest link in most Hi-Fi signal chains. The LA4 removes the weak link while optimising the system noise performance at each volume setting.

The award-winning LA4 is designed to keep noise and distortion below the 0-dB SPL threshold of hearing at each of the 256 volume control settings. No preamplifier delivers a higher degree of transparency.

The LA4 provides input selection and volume control without adding an "electronic fingerprint" to the music. Discover the difference! Listen to the music, not the electronics.

Relay-Controlled Volume

• High-Precision Low-Impedance 256-Step Attenuator
• Low-Noise 16-Step Input Gain Stage
• Control Range is +15 dB to -127.5 dB in 0.5 dB Steps
• High Precision Laser-Trimmed Thin-Film Resistors
• 12 Relays per Output Channel - 24 Total
• Precision Make-Before-Break Timing - Prevents Switching Noise

Extended Frequency Response

• Ultra Wide 0.1 Hz to 500 kHz Response
• Bass is Delivered Without a Phase Shift
• Fast, Distortion-Free Transient Response
• Linear Phase Response
• Accurately Reproduces the Audio Waveshape
• Precise Rendering of Stereo Width and Depth
• Focused 3-D Stereo Image

Fully-Balanced Signal Path

• 2 Pairs of Balanced Line Inputs
• Fully-Balanced Differential Input Amplifiers
• Fully-Balanced Relay-Controlled Gain Stage
• Fully-Balanced Relay-Controlled Attenuation Stage
• Fully-Balanced Output Line Drivers
• Left, Right and Mono - Balanced Line Outputs
• Unbalanced Inputs and Outputs Included

System Optimisation

• Establishes an Optimal Gain Structure Between the DAC and Power Amplifier
• System Noise Performance is Optimized at all Volume Settings
• Matches Hi-Fi to Pro Signal Levels
• Matches Unbalanced to Balanced Signal Levels
• Perfect Match Between a DAC3 and AHB2
• Use a Single Remote to Control an All-Benchmark System

Special Features

• Colour Touch Screen
• Balance Control
• -20 dB "Dim" Function
• Soft Unmute
• Two Bidirectional 12V Trigger Ports
• Gain Offset Adjustments for Each Input
• Home Theatre Bypass Function

Studio Applications

• Precise, Repeatable Gain Settings Calibrated in dB
• Studio +28 dBu Input and Output Capability
• Instant A/B Switching Between Sources with Calibrated Input Offsets
• Volume Knob uses Long-Life Heavy-Duty Optical Encoder
• Long-Life Telcom-Grade Gold-Contact Relays
• Rack-Mount Version Available

DESIGNED, ASSEMBLED, AND TESTED N THE USA

This Benchmark product was designed, assembled, and tested in the USA using USA and imported components. Most major components are made in USA.