Line One
Precise & Natural Sound
LKV’s Line One preamplifier offers state-of-the-art sonic excellence and operational flexibility that suits virtually every high-end audiophile system.
Designed by Bill Hutchins, the Line One reproduces music with natural tones, neutral frequency balance, accurate detail, startling dynamics, and a relaxed, engaging presentation. The bass is deep and tight, the midrange rich and smooth, and the highs extended and airy. The Line One’s soundstage is broad and deep, offering tangible images.
Uniting LKV’s products is the AZF circuit: a Class A, Zero-Feedback differential amplifier with short signal paths employing hand-matched, discrete JFETs for vanishingly low noise and distortion.
An external power supply with seven stages of regulation and filtering assures clean DC power for the dual-mono topology using two identical, separate circuit boards.
Premium parts assure the purity of the musical signal is maintained. A four-gang stepped attenuator using discrete, 0.1% tolerance resistors controls volume. ELMA switches with gold plated contacts provide input selection. All resistors are Vishay/Dale metal film, 1% tolerance and signal path capacitors are WIMA polypropylene. Four-layer circuit boards reduce noise by shortening signal traces and connecting all ground connections to a ground plane. Internal signal wires are solid-core with Teflon insulation.
The Line One offers six inputs, two balanced and four single-ended, and two outputs of each type. When using the single-ended inputs and/or outputs, all amplification occurs in the differential gain blocks. Gain can be adjusted to either 4 dB or 10 dB for both single-ended and balanced modes. Front panel controls include mute switches and power on/off.
Line One Features
Line One Specifications
AZF Circuit. Fully differential, class A, zero feedback gain blocks implemented with low-noise JFETs.
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Cascode gain circuitry, stiff current source biasing and hand matched JFETs (Idss less than ± 0.1 mA) to minimize distortion.
High current JFET output buffer suitable for driving long cables and low impedances.
Extensive on-board voltage regulation and filtering assure clean, stable power supply rails for the gain circuitry.
Soft start protection to prevent component failure.
Dual mono construction with separate circuit boards to reduce crosstalk and enhance imaging.
Four-layer circuit boards reduce the length of the signal path and connect grounds to the same plane to minimize noise.
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1% tolerance metal film resistors.
Polypropylene dielectric signal path capacitors.
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Separate power supply with custom designed toroidal power transformer and low-noise HEXFRED rectifier diodes.
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Two balanced and four single-ended inputs per channel.
Two balanced and two single-ended outputs per channel.
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32-step attenuator volume control, with 0.1% tolerance resistors.
User selectable 4 dB (low) and 10 dB (high) gain settings in both single ended and balanced modes.
Balanced Output with Volume Control at Maximum
Gain: 4 dB (low) or 10 dB (high), selectable
Total Harmonic Distortion, 2 V out at 1 kHz:
- 0.003%
THD+N, 2V out, 20Hz - 20 kHz:
- 0.005%
Frequency response:
- ± 0.15 dB from 20 Hz to 50 kHz.
Signal/Noise Ratio, 1 V output, 20 to 20 kHz:
- better than 103 dB.
Crosstalk L-R and R-L, 2V output at 2kHz:
- -115 dB
Clipping at 1% THD occurs at 19 V output
Single-Ended Output with Volume Control at Maximum:
Gain: 4 dB (low) or 10 dB (high), selectable
Total Harmonic Distortion, 1 V out at 1 kHz:
- 0.01% (4 dB) / 0.008% (10 dB)
THD+N, 2V out, 20 Hz – 20 kHz:
- 0.01%
Frequency response:
- ± 0.15 dB from 20 Hz to 50 kHz.
Signal/Noise Ratio, 1V output, 20 Hz - 20 kHz:
- better than 103 dB.
Crosstalk L-R and R-L, 2V output at 2K Hz:
- -115 dB.
Clipping at 1% THD occurs at 9.5 V output
Dimensions, Main Unit:
W: 43 cm, D: 33 cm, H 10 cm
W: 17 inches, D: 13 inches, H: 4 inches
4.3 kg, 9.5 pounds
Singled-Ended (RCA) & Balanced (XLR) Input
Singled-Ended (RCA) & Balanced (XLR) Output
Dimensions, External Power Supply:
W: 15 cm, D: 33 cm, H 10 cm
W: 6 inches, D: 13 inches, H: 4 inches
3 kg, 7 pounds
One meter umbilical cable