S4 now ships with toroidal output transformers.

 

 

S4 is the latest embodiment of Audial reference Model range of D/A converters, that started back in 2007. With a plenty of both new and old Audial unique solutions, the S4 produces the ultimate sonic experience. Its highest resolution and definition, and most pleasing tone at that, will bring you a new perspective on your music collection. And on the music, generally.

 

 

● Non-oversampling, real multibit TDA1541A DAC, with synchronous DEM clocking

● Master USB device (“asynchronous USB”), up to 384 kHz capable, with two low jitter clocks and galvanic isolation

● True 75 Ohm BNC S/PDIF input, with differential input termination

● High performance, zero feedback, hybrid output analog stage

● High quality parts, including Renesas and Toshiba semiconductors, Rubycon ZA capacitors, Vishay and Allen Bradley carbon resistors, and unique toroidal output coupling transformers (optional)

● Ten fully separate supplies, with three stage common mode filters, and low noise, fully discrete, zero feedback regulators

● Output impedance 3 Ohm plus 23 uF coupling capacitors, or 30 Ohm (transformers coupled)

● Extremely optimized layout, based notably on high quality SMT parts

● Includes mains isolation transformer, both as a mains filter and balanced power source

● Quality aluminum chassis

 

 

 

Harmonic distortion, capacitor coupled output, 1 kHz, -6 dBFS dithered sinewave, THD = 0.0029%

 

Harmonic distortion, transformer coupled output, 1 kHz, -6 dBFS dithered sinewave, THD = 0.0043%

 

Harmonic distortion, capacitor coupled output, 1 kHz, -60 dBFS dithered sinewave, THD = 0.9%

 

Harmonic distortion, transformer coupled output, 1 kHz, -60 dBFS dithered sinewave, THD = 0.9%

 

Intermodulation distortion, capacitor coupled output, CCIR IMD = 0.006%

 

Intermodulation distortion, transformer coupled output, CCIR IMD = 0.005%

 

Square wave 100 Hz, capacitor coupled output

 

Square wave 100 Hz, transformer coupled output

 

Square wave 11025 Hz, capacitor coupled output

 

Square wave 11025 Hz, transformer coupled output

 

 

S/PDIF stage bit clock 2.822 MHz, FFT analysis, ± 50 kHz span

 

 

 

USB stage bit clock 1.411 MHz, FFT analysis, ± 50 kHz span

 

 

 

 

  User manual

 

 

 

 

 

 

 

 

 

 

Recommended reading:

Model S4 is coming

Another story about TDA1541A: 384 kHz

Transformer coupling pros and cons