Stax
STAX SRM-500T Tube Driver
A full model change of the middle level vacuum tube output driver unit
STAX introduces a new vacuum tube output driver unit “SRM-500T”, the successor model of “SRM-006tS”. STAX custom-made low noise DUAL FET is installed on First Stage and the vacuum tube”6FQ7/6CG7″ is installed on Output Stage. STAX continued to use the traditional circuit design which is perfect for STAX vacuum tube driver and improved the power efficiency. Finally SRM-500T achieved the sound quality improvement.
In addition to the conventional power transformer for the high voltage circuit, the newly designed power transformer with the winding for the low voltage circuit is installed in SRM-500T. The low voltage winding enables to improve the power efficiency and achieve further power saving and better sound quality than the conventional vacuum tube output driver units such as SRM-006tS.
The new chassis which is more rigid than the conventional model is installed. The chassis has a hybrid structure using a lot of non-magnetic aluminum and further reduces the effect of the environmental noise factors such as vibrations. The inputs are RCA and XLR, the mutual exclusion inputs. The custom made concentric dual volume knob which is common to STAX products and RCA PARALLEL OUT functions are installed same as the conventional driver units. All electric components are strictly selected considering the environment. Also the sound quality and the performance is improved. The complete DC amplifier configuration that the signal circuit includes no coupling condensers is one of the biggest traditional features.
The clear and highly transparent sound, a feature of the vacuum tube circuit and the warm and wide sound texture is maintained and the thickness of the low-mid range is brushed up. This is the new choice for the combination with the advanced lambda series (SR-L300/SR-L500 MK2/SR-L700 MK2).
Rear Panel
Type
FET input + vacuum tube output hybrid DC amplification driver unit
Vacuum tube
6FQ7/6CG7
Frequency response
DC – 90kHz (with one SR-009S)
Gain
60dB
Harmonic distortion
0.01% or less (1kHz/100Vrms output)
Input impedance
50kΩ (RCA), 50kΩx 2 (XLR)
Maximum output voltage
300Vrms (1kHz)
Bias voltage
DC580V
Operating temperature / humidity
0 to 35 degrees C / less than 90% (non condensing)
Input terminal
RCA x 1, XLR x 1
Output
RCA parallel output terminal
Power consumption
38W
Dimension
195W x 102 H x 376 D mm (maximum protruding portion included)
Weight
3.4kg