Audio Research LS7 Line Stage Amplifier
The Audio Research LS7 is a vacuum tube line-stage preamplifier designed to deliver wide bandwidth, low distortion and classic Audio Research transparency. Introduced in the mid-1990s, the LS7 remains a respected example of ARC’s minimalist line-stage engineering philosophy.
It utilises 6922 (E88CC) dual-triode vacuum tubes and features electronically regulated high- and low-voltage power supplies to ensure stable operation and consistent performance.
Designed for integration with high-quality power amplifiers, the LS7 offers low output impedance, moderate gain and broad frequency response, making it compatible with a wide range of solid-state and tube amplification systems.
Key Features
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Vacuum tube line-stage preamplifier
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4 × 6922 / E88CC dual triode tubes
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Electronically regulated power supply
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Wide bandwidth design
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Low distortion topology
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Line-level inputs only (no built-in phono stage)
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Analogue volume control and source selection
Specifications
| Specification | Detail |
|---|---|
| Frequency Response | ±0.5 dB, 1 Hz – 100 kHz |
| -3 dB Points | Below 0.1 Hz and above 300 kHz |
| Total Harmonic Distortion | < 0.01% at 2V RMS output (typically 0.005% midband) |
| Gain | Main Output: 13 dB (unbalanced) |
| Tape Output: 0 dB | |
| Input Impedance | 100kΩ |
| Inputs (5) | Tape, Tuner, CD, Video, Aux |
| Output Impedance | 200Ω (main output) |
| Recommended Load | 60kΩ and 100pF |
| Load Range | Minimum 20kΩ / Maximum 1000pF |
| Maximum Input | 20V |
| Rated Output | 2V RMS, 1 Hz – 100 kHz into 60kΩ load |
| Maximum Output | 25V RMS at 0.5% THD, 1 kHz into 100kΩ |
| Noise | 15µV RMS maximum (IHF weighted) at main output with gain minimum (more than 102 dB below 2V RMS output) |
| Tube Complement | 4 × 6922 / E88CC dual triodes |
| Power Supplies | Electronically regulated low- and high-voltage supplies; solid-state rectified |
| Line Regulation | Better than 0.01% |
| Power Requirements | 100–135VAC 60Hz or 200–270VAC 50/60Hz |
| Power Consumption | 130 watts maximum |
| Dimensions (W × H × D) | 19″ (48 cm) × 5¼” (13.4 cm) × 10¼” (26 cm) |
| Handle Extension | 1½” (3.8 cm) forward of front panel |
| Rear Fittings Extension | ½” (1.3 cm) |
| Weight (Net) | 9.8 lbs (4.5 kg) |
System Integration
With a 13 dB gain structure and low output impedance (~200 Ω), the LS7 is well suited to driving most power amplifiers with input impedances of 60 kΩ or higher. Its wide bandwidth design (1 Hz – 100 kHz) ensures stable frequency extension well beyond the audible range.
As a dedicated line-stage, an external phono preamplifier is required for vinyl playback systems.
The Audio Research LS7 is a straightforward, tube-based line preamplifier built around proven 6922 circuitry and regulated power supply design. Offering wide frequency response, low distortion and stable output characteristics, it remains a solid choice for systems seeking classic Audio Research line-stage performance.
Condition: Good
Colour: Silver face, Black body
Note: Product does not include additional accessories or original packaging
R15,800.00
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