Power Amplifiers

Wyred4Sound SX-1000 Monoblock Power Amplifier



Wyred4Sound has entered into the high end audio market with plenty of experience behind its doors. Born from the skilled minds and hands of EJ Sarmento and Rick Cullen of Cullen Circuits, these two have been providing high end components for the audio industry for years. Rick used to be the production manager for PS Audio, until in 1990 he started Cullen Circuits- a provider and consultant to companies such as PS Audio, Genesis Technologies, Camelot and more. EJ has worked for Cullen Circuits since its early inception, developing his skills as a technician. While dabbling in class D ICE power modules, EJ created the first W4S amp, the 200S. Wyred4Sound has expanded their line of products to include not only the SX-1000 monoblock amps, but also stereo, multichannel and integrated amps, and DACs.


  • Design: Monoblock Power Amplifier, Class D
  • Power Output: 570 Watts RMS into 8 Ohms, 1,140 Watts RMS into 4 Ohms
  • MFR: 20 Hz - 20 kHz, ± 0.4 dB
  • THD+N: 0.2% at Rated Output
  • IMD: (CCIF): 0.0005%
  • Efficiency: 79%
  • Sensitivity: 2.95 Volts
  • Output Impedance: 0.005 Ohms
  • Idle Power Consumption: 15 Watts
  • Dimensions: 4.1" H x 8.5" W x 13.5" D
  • Weight: 14 Pounds/each
  • MSRP: $1,199/each USA
  • Wyred4Sound

Class D amplification hasn't exactly gotten the warmest reception in the high end audio industry. In a world dominated by hot and heavy class A and class AB amps, class D has been the ugly stepchild. However, many recent enhancements in ICE power modules have made amplifier designers take a second look into the benefits of class D - cool running, efficient, and very fast. Using a power supply that operates at 100kHz and an amplifier section that runs at 500 kHz (typical class AB amps run on 60Hz power supplies), a well designed Class D amp can adapt to power needs, or musical dynamics, in an instant.

W4S enhances the ICE modules by upgrading the analog section for better low end extension and overall smoothness to the sound. The question is, does their design work? Is a Class D ICE module powered amp capable of competing with the tried and true old school room heating amps?