UD-01 USB DAC  

• Positioning: A basic desktop DAC built for clear digital-to-analogue conversion.  
• Description: Uses Burr-Brown chip technology with dual-channel buffering and low-pass filtering to maintain clean signal output. Compared to the preamps and amplifiers in the lineup, it offers straightforward functionality best suited for simple, low-budget desktop use without extra features.

Pre-Amp  

• Positioning: An entry-level active preamplifier designed for compact affordability.  
• Description: Uses a hybrid design with Burr-Brown OPA627 op-amps and BUF634 buffers along with an auto-select line input to improve signal clarity. Compared to the UD-01, it integrates a built-in transformer and line filter to reduce interference, serving users needing enhanced signal processing in a moderately sized room while keeping expenses low.

PREference  

• Positioning: A refined second-generation preamplifier offering enhanced signal control.  
• Description: Adds a current booster and diamond buffer technology along with selectable gain settings and integrated phonostage options to boost performance. Compared to the standard Pre-Amp, its advanced circuitry provides more precise and versatile amplification.

T20 Audio AMP  

• Positioning: A compact power amplifier engineered for small to medium rooms.  
• Description: Built around the Tripath TA2020-20 DPP chip that offers increased power efficiency with low distortion and simple connectivity through gold-plated terminals. Compared to the earlier DAC and preamp units, its design focuses on delivering robust output and dynamic range.

HQ-1 Headphone AMP  

• Positioning: A premium class A headphone amplifier designed for high-end desktop audio.  
• Description: Features a two-box design that separates the linear regulated power supply from the MOSFET-based amplification circuitry to ensure smooth, low-noise operation. Compared to the UD-01, Pre-Amp, and T20, it delivers superior detail and clarity for critical listening.