Audiophonics HPA-S400ET Amplifier Class D Stereo Purifi 2x400W 4 Ohm *** 1,490.00 € tax incl. - 1,241.67 € tax excl. ***https://www.audiophonics.fr/en/powe...ass-d-stereo-purifi-2x400w-4-ohm-p-14393.htmlRotated, clarified and optimized
Audiophonics Interface Card [ Both modules are
driven in opposite phase, to cancel out the «Power-Supply Pumping» effect. This allows greater stability in the power supply by alternately distributing current draws on each rail, thus increasing its overall capacities.
We opted for a regulation with
two voltage levels in order to optimize the power supply to the PDOs and the auxiliary voltage supplied to the modules. This allows the OPAs to be
powered with a high voltage (18V) for better overall performance, and allows them in turn to provide the voltage needed to reach the amplifier's maximum output level. While still maintaining the auxiliary voltage required by the modules.
Each channel uses its own
Analog Devices OP275 AOP. They are based on a hybrid Bipolar / JFET technology. Bringing precision and musicality. They are mounted
on a socket allowing their possible replacement.
To suit all uses we opted for
3 gain settings adjustable by jumper on the interface card:
*
Gain of + 9.5dB, for a total of 22.3dB (default) Maximum power reached with a signal of ~ 3.2V RMS
*
Gain of + 15.5dB, for a total of 28.3dB Maximum power reached with a signal of ~ 1.6V RMS
*
Bypass: in this case the signal passes directly from the inputs to the modules, allowing the lowest possible gain of 12.8dB. This mode can be interesting when using a
powerful preamplifier, capable of driving a load of 2 to 4kOhm and reaching a voltage of ~ 10V RMS ]