Line Amplifiers

THE ULTIMATE LINE AMPLIFIERS

The LA4 and HPA4 are the ultimate line amplifiers for professional applications or for reference-quality Hi-Fi applications. They features balanced and unbalanced inputs and outputs. They include fully-balanced high-precision 256-step relay controlled gain stages. The gain range is -112 dB to +15 dB in 0.5 dB steps. The relay closures are precisely timed to provide silky-smooth volume changes. They also include relays for mute, balance, input selection, and -20 dB dim.

For professional applications, both products are available in 19-inch, 2-RU rackmount versions.

The HPA4 includes the revolutionary THX-888 headphone amplifier.

The LA4 and HPA4 line amplifiers are an excellent choice for controlling the levels to studio monitors, and power amplifiers in the most critical listening environments. No other analog-to-analog line amplifiers offer higher performance!

Benchmark Line Amplifier defines the current state of the art (LA4 and HPA4):

• Gain Range -112 to +15 dB in 0.5 dB steps - Fully Balanced, Relay Controlled
• THD < -125 dB (0.00006%)
• SNR > 135 dB, unweighted, 20-20 kHz
• SNR > 137 dB, A-weighted
• Frequency Response - 0.003 dB at 10 Hz, -0.001 dB at 20 kHz
• - 3 dB Bandwidth exceeds 0.1 Hz to 500 kHz
• Output Impedance 60 Ohms
• Output Noise < 1.9 uV at Unity Gain, 20-20 kHz
• Maximum Input and Output Level, +28 dBu
• Crosstalk < -133 dB @ 1 kHz, -116 dB @ 10 kHz

The THX-888 Headphone Amplifier also defines the state of the art (HPA4 only):

• Gain Range -112 to +15 dB in 0.5 dB steps - Fully Balanced, Relay Controlled
• THD < -125 dB (0.00006%)
• SNR > 131 dB, unweighted, 20-20 kHz
• SNR > 135 dB, A-weighted
• Frequency Response - 0.003 dB at 10 Hz, -0.001 dB at 20 kHz
• - 3 dB Bandwidth exceeds 0.1 Hz to 500 kHz
• Output Impedance, near 0 Ohms
• Output Noise < 2.45 uV at Unity Gain, 20-20 kHz
• Maximum Output Power, 6 Watts into 16 Ohms
• Maximum Output Voltage, 11.5 Vrms into 300 Ohms
• Crosstalk < -133 dB @ 1 kHz, -115 dB @ 10 kHz (XLR4)