MEIER-AUDIO
CORDA


CORDA QUICKSTEP
Technical details:

Measures: 8.8 x 6.6 x 2.2 cm

Weight without battery: 115 gr.

Supply voltage: 6 .. (9) .. 15 Volts DC

Mean current uptake: 35 mA / 20mA
(high/low-current-consumption-mode)

Discrete volume control. Typical stepsize 1.5 dB, 31 steps.

Maximal amplification: -3 / 14 dB (low/high gain)

Active balanced headphone ground.

Star-grounding and ultra short signal paths.

Input impedance: 120kOhm / 17 kOhm

Output impedance: < 1 Ohm

The unit runs from a single 9V battery or an external regulated powersupply (upto 15V). Internally the supply voltage can be doubled (high current consumption mode) to increase driving capacity.

Noise is removed by LC-filtering of the supply voltage.

Total buffer capacity is 4700 uF to lower the effective battery impedance.

RF-noise (iPhone!!) is removed by extensive filtering of the input signal.

For amplification five single OPA209 opamps are used for maximal sonic performance.(No dual or quad-opamps!)

The heavy-duty (!!) 3.5 mm sockets are gold-plated.

Inside the signal path only metal-resistors and high-quality film-capacitors are used (polypropylene).

The enclosure is made entirely of aluminium.

Accessories: 2 mini-mini interconnects (goldplated)
......................Tool to open the amp
Technically the QUICKSTEP is a very sophisticated portable amplifier. This amp was designed to provide the best possible portable sound with a minimum of compromises towards size and current consumption.
The amp not only uses the concept of active balanced ground but also has a discrete volume control (32 positions, two gain settings). This volume control is not a standard industrial solution but uses a concept in which the position of an analog potentiometer is measured using a low-power ADC and in which the output of this ADC is used to control electronic switches that set the volume level. The result is a very clean and detailed sound without any channel imbalances.
The 3.5 mm sockets, mechanically often the weakest point of a portable amplifier, are heavy duty. Also much care is taken that the amp does not react to RF-signals at the input, thus making it immune to RF-pollution caused by mobile headphones.
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