The MEDUS has its origins in our product line for professional mastering studios. Mastering Engineers have the Golden Ears to give the music recordings the final touch before their release. So the MEDUS is as transparent as it can be. Hands down the best Digital to Analog Converter money can buy.
MEDUS is a stereo 24 Bit/192 kHz Digital to Analog Converter designed with the aim of keeping an absolutely uncompromising audio signal path. Much detail and thought was spent on the digital input as well as the analog output stage. Both have in common the purest possible approach in audio design, aspiring for nothing less than excellence. This is coupled with an ergonomic design that gives the user immediate access to all necessary functions, while keeping an uncluttered and thus easy-to-use front panel. This combination makes a truly professional D/A converter catering for the highest expectations.
The MEDUS works with AES/EBU or S/PDIF sources and optionally acommodates USB, Ethernet, Firewire and ST glass fibre inputs. The USB input handles PCM as well as DSD signals. An IR remote unit controls all functions.
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, Ethernet 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 RCA
- 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 USB, Ethernet, 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 OP2-BP) per channel.
All analog processing is done with our own discrete operational amplifier modules, the Weiss OP2-BP. The OP2-BP is arguably the best audio operational amplifier currently available. Four OP2-BP are used per channel, two for current to voltage (I/V) conversion and two for the balanced and unbalanced output stages. The OP2-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 (example)
- 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
- USB connector.
- Ethernet connector.
- 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
- Connecting the MEDUS to a Local Netwerk via the Ethernet input and stream audio data directly from a NAS or from Internet to the Medus. This under control by and app on a tablet or smart phone.
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.
- Mains voltage: 100…120 / 200…240 Volt
Fuse rating: 500 mA slow blow
- Power consumption: 80 VA max.
- Power consumption in standby: 2 VA max.
- Depth: 30 cm
- Width: 45 cm
- Height: 6,6 cm
- Height with feet: 7,4 cm
- Depth: 2,5 cm
- Width: 6,2 cm
- Height: 16,9 cm
- (3) XLR connectors
- (1) TOSLINK connector (optical)
- (4) RCA connectors
- All inputs accept professional or consumer standard, i.e. accept AES/EBU or S/PDIF signals
- Sampling frequencies; single wire scheme: 44.1kHz, 48 kHz, 88.2 kHz, 96 kHz, 176.4 kHz or 192 kHz on any of the four inputs
- Sampling frequencies; dual wire scheme: 88.2 kHz, 96 kHz, 176.4 kHz or 192 kHz on inputs 1 and 2
- Sampling frequencies of 352.8kHz or 384kHz: On USB input
- DSD64, DSD128: On USB input
- Sampling frequency tolerance: ±80 ppm
- Maximum input word-length: 24 Bits
- (2) XLR Connectors
- (2) RCA Connectors
- Servo-less, DC coupled, short circuit proof output circuitry
- Output impedance: < 100 Ω
- Output level: variable from −4.0 dBu to +27.0 dBu balanced on XLR connectors (−10.0 dBu to +21.0 dBu unbalanced on RCA connectors) with 0 dBFS input, in 1 dB steps (−4 dBu is 0.49 V, +27 dBu is 17.35 V, −10 dBu is 0.245 V, +21 dBu is 8.67 V)
- Output stage: Discrete Class A
D/A Converter chip
- Over-sampling multi-bit sigma-delta converter
- Four converters per audio channel
- Synchronized via the input signal
- Extremely efficient Jitter attenuation down to subsonic frequencies
- Sampling frequencies: 44.1 kHz, 48 kHz, 88.2 kHz, 96 kHz, 176.4 kHz, 192 kHz, USB only: 352.8 kHz, 384 kHz
Up-sampling, jitter reduction
The measurements below have been taken at the following conditions (unless noted otherwise): 1 kHz, +24.0 dBu output level (−3 dBFS input level), 192 kHz sampling frequency (fs).
- Fs = 44.1 kHz: 0 Hz…20 kHz: within ±0.25 dB
- Fs = 48 kHz: 0 Hz…20 kHz: within ±0.25 dB
- Fs = 88.2 kHz: 0 Hz…30 kHz: within ±0.75 dB
- Fs = 96 kHz: 0 Hz…30 kHz: within ±0.75 dB
- Fs = 176.4 kHz: 0 Hz…40 kHz: within ±0.75 dB
- Fs = 192 kHz: 0 Hz…40 kHz: within ±0.75 dB
Signal To Noise Ratio (SNR) at −40 dBFS input:
- > 129 dB un-weighted
(relative to full scale output)
- > 132 dB A-weighted
(relative to full scale output)
- At 0 to −100 dBFs input level:
< ±0.05 dB deviation from ideal
- At −100 to −120 dBFs input level:
< ±0.2 dB deviation from ideal
Total Harmonic Distortion plus Noise (THD+N) ratio:
- < −112 dB @ −3 dBFS input
(0 dBFS = +27.0 dBu)
- < −115 dB @ 0 dBFS input
(0 dBFS = +27.0 dBu)
< −110 dB, 0…20 kHz