A review or two! http://www.headfonia.com/supersharp-apex-glacier/2/http://www.headfonia.com/supersharp-apex-glacier/2/ http://audio-head.com/apex-glacier-portable-headphone-amp-and-dac/
The newest creation from designer/engineer Pete Millett for
the Apex High Fi Audio line is the portable Apex Glacier. This amp is so slim
The Glacier has a great headphone amplifier section. The DAC
section is 24/96 and sounds fantastic. The Glacier also has an excellent power
supply to insure the electronics are not lacking for power!
Features include three gain settings, separate USB inputs
for charging the amp and Digital In, Digital volume control, color
volume/on/off indicator and 4 connector strips to connect your Glacier and
portable source together. No rubber bands or sticky mess as the connector
strips are removable and leave no residue!
But the best features of all are the footprint of the Glacier.
It is ultra-thin and is the same footprint as the most popular portable sources
– the iPod and iPhone as well as many other portable players.
24-bit, 96-kBPS USB
– A Cirrus Logic DAC driven by a Tenor isochronous USB interface provides
support for up to 24-bit, 96-kSPS digital audio from a USB host. This implementation requires no drivers, and
works seamlessly with Windows or Mac PCs or other devices with a USB host port
(including the iPad using the Apple CCK).
Charging from the USB DAC port can be enabled or disabled, to allow use
with low-power portable devices that cannot supply enough current to charge the
Stepped Attenuator - No cheap volume
control pot here. Small potentiometers
are notoriously bad - they mis-track, get noisy, and break. So the Glacier uses a
microprocessor-controlled analog stepped attenuator. Each of the 32 steps changes the volume level
by a precise 2dB, and the gain difference between channels is less than ±0.2dB
- compare that to normal pots that at best provide ±3dB! The current volume setting is indicated by
the color of the front-panel LED. In addition, you can select 0dB, 10dB, or
20dB of maximum gain at the press of a button, to accommodate all sources and
High output power - What's the point of
a headphone amp if it can't drive any more than your iPod? Using a current feedback amplifier, the Glacier
puts out 2.6V RMS (7.4V P-P) and up to 100mA of output current, so can easily
drive nearly any headphones. The highly
efficient, high frequency regulated power supply guarantees full output power
over the life of the battery, with low noise and high output current for
powerful bass response, even with low impedance headphones.
DC-coupled design - The signal path in
most portable amps is AC-coupled, with a single power supply. This requires the audio signal to pass
through multiple capacitors, which degrade the sound and limit frequency
response. The Apex Glacier has a bipolar
power supply, allowing the audio path to be DC-coupled. That means the low-frequency response extends
- The Glacier contains a lithium-polymer battery which will power the amp for 12-15
hours at typical listening levels. It
recharges in about 2 hours from any USB port, or a USB wall charger. You can also operate it while plugged in to
keep the battery topped off.
case – A
full metal enclosure with stainless-steel skins makes the Glacier slim, strong,
and resistant to EMI (electromagnetic interference). Sized to match common portable devices, the
Glacier is the thinnest portable headphone amp made!
Frequency response: DC to >100kHz,
±1dB; 20Hz - 20kHz ±0.1dB @ 1V out
output: >2.6V RMS into 150Ω; >1.7V RMS into 32Ω
source impedance: Approximately 2Ω
0.005% @ 1V RMS out, 20Hz - 20kHz into 150Ω
RMS, unweighted, integrated over 20Hz - 20kHz
DC offset: <5mV
input level: 2V RMS
tracking (gain difference between channels, all volume steps): <±0.2dB
gain: 0dB, 10dB, or 20dB, ±<0.5dB
114mm long x 65mm wide x 9mm thick