Sony TA-F501
A full digital amplifier from Sony's System501 series released in 2007. Features 32-bit S-Master Pro technology, which was advanced for its time. However, from today's technical standards, its 6Ω-only design specification, limited input terminals, and overwhelming price disadvantage compared to currently available products with equivalent performance are notable drawbacks. While having historical value, it falls short of modern alternatives in terms of practicality and cost-performance.
Overview
The Sony TA-F501 is a full digital integrated amplifier from the System501 series released in spring 2007. It was designed with the concept of “adult component system” and featured the advanced 32-bit S-Master Pro technology for its time. The amplifier has a rated output of 50W/6Ω and practical maximum output of 75W+75W/6Ω, with a unique 6Ω-only design specification. It covers a frequency response range of 10Hz to 40kHz and provides 3 analog inputs and 4 digital inputs. The manufacturer’s suggested retail price was ¥89,000 excluding tax, but production has been discontinued, with current used market prices averaging around ¥37,000.
Scientific Validity
\[\Large \text{0.2}\]The adoption of 32-bit S-Master Pro technology theoretically enables reduction of quantization noise in digital processing. However, this represents 2007-era technology standards, showing significant performance gaps compared to current state-of-the-art digital processing technologies. Without published measurement data for THD+N, SNR, and frequency characteristics, objective evaluation is difficult. The 6Ω-only design creates compatibility issues with standard 4Ω or 8Ω speakers, presenting practical limitations. While digital processing audio quality improvements exist, they are limited by current standards.
Technology Level
\[\Large \text{0.5}\]For 2007 standards, the adoption of advanced full digital amplifier technology was commendable, bringing Sony’s high-end ES series 32-bit S-Master Pro technology to a mainstream price point. However, from current technical standards, it has become obsolete in many aspects including Class-D amplifier technology, digital signal processing, and power efficiency. The 6Ω-only design appears to be a design misjudgment rather than a technical constraint. The input terminal configuration cannot accommodate today’s diversified source requirements. While technical completion was high for its era, it falls below average from today’s perspective.
Cost-Performance
\[\Large \text{0.1}\]At the used market price of approximately ¥37,000, it significantly underperforms compared to currently available digital amplifiers with equivalent performance. The Fosi Audio V3 (¥13,600) delivers 300W×2 output with modern Class-D technology using TPA3255 chips. The SMSL A12 (approximately ¥15,000) features MA12070 chips with 80W RMS×2 and excellent 0.005% distortion performance. The TA-F501’s 50W/6Ω output is low by current standards, and the 6Ω-only constraint severely limits practicality. CP = 13,600 ÷ 37,000 = 0.37, but considering functional constraints, the practical CP is approximately 0.1.
Reliability & Support
\[\Large \text{0.6}\]Basic quality as a Sony product is ensured, with high satisfaction ratings of 4.58/5.0 from 32 reviewers on price comparison sites. However, being a 2007 product, it has been discontinued for 17 years, creating issues with manufacturer support and parts supply. Repair support cannot be expected, making fault resolution difficult. While maintaining good quality for its era, it faces significant constraints in reliability and support from today’s perspective.
Rationality of Design Philosophy
\[\Large \text{0.3}\]While the “adult component system” concept is understandable, the 6Ω-only design decision lacks rationality. Standard speaker impedances are predominantly 4Ω or 8Ω, making the 6Ω-only design divergent from market needs. Full digital processing adoption was rational for its time, but input terminal configuration and digital processing specifications cannot accommodate today’s diversified sources. The compact design is commendable, but the balance between performance and practicality is inadequate.
Advice
Purchase consideration is not recommended at present. Compared to the used price of ¥37,000, currently available new digital amplifiers (Fosi Audio V3: ¥13,600, SMSL A12: approximately ¥15,000) are superior in output, functionality, and future-proofing. The 6Ω-only design particularly presents significant practical constraints, potentially causing compatibility issues with standard speakers. Unless there is special attachment to Sony’s System501 series or value placed on audio historical collection purposes, strongly recommend considering current alternatives.
(2025.7.6)