The MEDUS employs a twin metal frame. The inner chassis is made of steel and acts as a very effective shield against electrostatic and electromagnetic radiation. The outer frame is made of massive anodized aluminium for additional shielding, resulting in optimal heat convection and beautiful looks.
A powerful non-switching power supply is used. All sensitive voltages have their own regulators which are separated between left and right channels. The result is an analog output free of “digital noise” and channel crosstalk. The power switch activates a semiconductor relay which only switches on or off at zero crossings of the mains voltage. This assures a glitch free power switching. The mains transformer sits in a mu-metal shielding box.
The MEDUS is synchronized by the input signal present at the selected input. Several signal re-clocking schemes are combined for extremely high jitter attenuation down to subsonic frequencies, making the MEDUS virtually immune to jitter. With the USB or Firewire inputs the master clock is generated by the MEDUS.
There are a total of four inputs with the following input sockets:
– Input #1: AES/EBU on XLR or RCA
– Input #2: AES/EBU on XLR or RCA
– Input #3: AES/EBU on XLR or USB
– Input #4: AES/EBU on TOSLINK or RCA
Sampling frequencies can be 44.1, 48, 88.2, 96, 176.4 or 192 kHz. Inputs #1 and #2 can be used for the dual wire scheme of transferring 88.2 kHz…192 kHz data. All inputs accept up to 24 Bits of data word-length. Optional inputs are Firewire or ST type glass fiber.
Signals at 44.1 or 48 kHz sampling frequency are up-sampled in the MEDUS’ DSP chip, using our own up-sampling algorithms. Thus the DAC chip always receives signals at a 88.2 kHz minimum sampling frequency.
The 32 Bit DAC chip up-samples the input signal to about 1.5 MHz. Four D/A conversion channels are used per audio channel, resulting in exceptional performance specifications. The I/V conversion after the DAC chip uses two of our own discrete OP-AMPs (the OP1-BP) per channel.
All analog processing is done with our own discrete operational amplifier modules, the Weiss OP1-BP. The OP1-BP is arguably the best audio operational amplifier currently available. Four OP1-BP are used per channel, two for current to voltage (I/V) conversion and two for the balanced and unbalanced output stages. The OP1-BP run in class A mode for all common loads. Output levels can be set with a rotary switch at the back of the unit. The level range is 32 dB with a 1 dB step resolution. The outputs are symmetrical on XLR connectors and asymmetrical on RCA connectors. No sound degrading servo mechanisms or AC coupling capacitors are used.
Front panel controls
The power switch allows to switch on or off the MEDUS unit. Four switches select one out of four input sources. A display conveys information on the selected input, the sampling frequency, the output level, the oversampling filter type, the absolute output polarity, the mute status and the coarse output level setting
Allows to control all functions of the MEDUS, namely: The input selected for conversion, the output level, output muting, the coarse output level, the absolute polarity, the oversampling filter type, the display brightness.
Back panel elements from left to right
– Analog outputs on XLR and RCA connectors with output level switch.
– Digital inputs 1…4 (three XLR, three RCA, one USB and one TOSLINK connector).
– Mains connector with fuses and voltage selector.
Optional back-panel elements
– Firewire connector.
– ST type glass fiber connector.
The MEDUS can be used in a variety of configurations. In all cases the MEDUS can be used as a pre-amplifier as well. This allows to reduce the number of components in a playback system by connecting the MEDUS directly to the power amplifier. Typical applications are:
– Connecting a computer via USB for file playback, including DSD file playback
– Connecting a CD Transport
– Connecting a radio or TV e.g. via the TOSLINK input
With the optional inputs (Firewire or ST glass fiber) the connectivity is further enhanced. E.g. with the ST glass fiber it is possible to connect the MEDUS to the JASON CD Transport directly via a glass fiber connection.