The Peak
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peak
[peek]
–noun
1.
the pointed top of a mountain or ridge.
2.
a mountain with a pointed summit.
3. the pointed top of anything.
The Apex Peak
represents a fresh approach to a mid-priced headphone amplifier and preamp.
The Peak is a hybrid amplifier, pairing a 6SN7 vacuum tube voltage amplifier
stage with a class-A single-ended MOSFET output stage. Unlike some hybrid
amplifiers on the market, the Peak generates a true high voltage B+ supply to
operate the tube where it belongs – at a very linear operating point.
The single-ended MOSFET output stage is DC-coupled to the outputs to provide
excellent drive capability and deep bass response. No negative feedback
whatsoever is used in the Peak.
Three inputs, selected by a front panel switch, and a line output (which is
automatically muted when you plug in your headphones) are provided, so you can
use the Peak both as a headphone amplifier and a pre-amp for a loudspeaker
system. Relays are used to keep the signal path short and direct.
The standard Peak is powered by an external switching power supply. For
ultimate fidelity, the Volcano, an optional linear power supply is available
that matches the amplifier in appearance and performance. The Volcano uses
a low-noise toroidal transformer and a massive bank of filter capacitors to
provide high peak currents without significant voltage drop.
Unique design and quality parts combine to give the Peak optimum sound at an
affordable price. Unlike many so-called "high-end" audio
components, the Peak is not just a prettied-up marginal design implemented with
poor-quality parts from third-world nations. It is proudly hand-built in
the USA.
Click on the photos for a full resolution version
Review of the Apex Peak and Volcano by Tom Martin at Playback
a review from Srajan Ebaen at 6moons. Read
it here.
Measurements and Specifications
NOTE: Please read the page about headphone & amp specs!
Values are typical. Measured using a Volcano power supply.
Max output level into 150 ohms @ 1kHz: 6.6V RMS / 18.7V P-P / 290mW
Max output level into 33 ohms @ 1kHz: 5.7V RMS / 16V P-P / 980mW
Peak output current: 220mA
Input impedance: 50k ohms
Output impedance: 1.0 ohm
THD+N 1V 1kHz 150 ohms: 0.16%
THD+N 1V 1kHz 33 ohms: 0.11%
FR: 20-20kHz +/- 1dB
FR: -3dB 7Hz – 30kHz
Noise 400Hz-30kHz: 30uV
Max gain (Headphone out) 1kHz: 23dB
Max gain (line out) 1kHz: 17dB
DC Offset: +/- 10mV
Power: 120 or 240 VAC, 50-60Hz, 45 watts max.
Dimensions: 8.3" W x 10.3" D x 2" tall (excluding tube)
FFT: 1V RMS @ 1kHz into 33 ohms:
FFT: 1V RMS @ 1kHz into 150 ohms:
Frequency response:
THD+N vs. frequency
THD+N vs. output voltage (1kHz into 33 ohms):
THD+N vs. output voltage (1kHz into 150 ohms):
