Orpheus uses two tube gain stages with zero feedback and passive LCR equalizer with 2 inputs on RCA and one on XLR connectors. All inputs are balanced differential unless the grounding option is engaged on the RCA inputs. As we switch the ground plane when switching inputs there are no hum loops and induced ground noise.
The input stage is a super low noise D3a German Post tube used as a triode. Loaded by a constant current cascode it provides the necessary gain and output impedance to feed the custom passive LCR RIAA correction following it.
The switchable input transformer interfaces to MC cartridges and has selectable gain and loading impedance.
The equalization is passive and the next stage is another super low noise tube loaded by a transformer to bring the signal up to the necessary level and provide complete isolation of this sensitive circuit from the following components.
The filter is out of any gain loops and sits between the two gain stages protected from any unpredictable influences.
The equalization is realized through the use of constant impedance LCR filters using coils wound with OFC wire and silver capacitors.
This way that the input stage sees a constant load, making its behaviour predictable at any signal level.
The power supply of Orpheus uses a choke input full wave tube rectifier arrangement. This eliminates switching noise and any other disturbance that comes before the choke. The other benefit of this topology is that the choke keeps the voltage on the capacitor bank constant.
All this is governed by a microprocessor switching the appropriate combination of relays and monitoring the status and incoming command.
The chassis is milled in house from solid plates of different thickness aluminium that are interlocked together to form a ring like structure.
We have the power supply mounted on the left sidewall of this structure and the signal transformers on the right side. Two semi-flexible bars on which the motherboard and its heat sink are attached, which then support this ring.
The top and bottom plates link all sides of the ring with the flexible bars and the feet made from carbon doped plastic on flexible screws.
There are no screws visible anywhere on the chassis. And the chassis feels like a solid block. TECHNICAL SPECIFICATIONS Inputs 2 x RCA or XLR - MM or MC phone cartridges Outputs RCA or XLR Power consumption 50W Dimensions 432W x 400D x 120H mm Weight 15 kg Tube compliment 2 x D3a amplification 2 x 6C4П amplification 1 x 6Ц4П rectifier AVAILABLE FINISHES
Silver Anodized Aluminum
Black Anodized Aluminum
DOWNLOADS
Declaration of Conformity
Operating Manual
Orpheus
Brochure
Thrax
Brochure
251 Okolovrasten Pat, Delta Center |
1766 Sofia |
Bulgaria |
Telephone: +359 2 988 95 55 |
E-mail: sales@thraxaudio.com