Overview

The t.amp S-75 MK II is a 75W class power amplifier from Thomann’s house brand t.amp series. It delivers 2×75W at 4Ω and 2×45W at 8Ω, designed for music and voice amplification in small-scale fixed installations such as restaurants, cafes, hotels, and schools. It features balanced inputs (XLR, phone), bridge mode, speaker protection circuits, and fanless design for quiet operation. The unit is 19-inch rack 1U size weighing 7.5kg, employing conventional circuit design with a linear transformer.

Scientific Validity

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Performance evaluation based on official technical specifications reveals several limitations. The actual published specs show THD <0.1%, which falls into the problem level range according to measurement criteria (0.1% or above being problematic). SNR is specified as >80dB, which is at the borderline of the problem level (80dB or below being problematic) and far from the transparent level (105dB or above). Crosstalk performance is listed as >70dB at 1kHz, 8Ω, which meets the transparent level threshold (-70dB or below). The damping factor is specified as >150, clearing the transparent level (100 or above). Frequency response is 10Hz-50kHz (±1.5dB), which exceeds the transparent level range due to the wider tolerance. These specifications indicate substandard performance in key audio quality metrics, particularly THD and SNR.

Technology Level

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The conventional design employing Class AB circuitry and linear transformer shows no technical uniqueness or innovation. Basic specifications such as damping factor of 150 or higher and slew rate of 35V/μs are at industry standard level, but appear mediocre from modern design standards. While protection circuits and soft-start functions are incorporated, these are now standard features. The fanless design is commendable, but no special technological innovation to achieve this is evident. It is likely an OEM product with no traces of proprietary design. The non-disclosure of measurement data also suggests a lack of technical confidence.

Cost-Performance

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The actual price of the t.amp S-75 MK II is approximately 19,170 JPY (135 EUR, converted at 2025 exchange rate of 1 EUR = 142 JPY). As a competing product with equivalent or superior output and functionality, the AIYIMA A07 (13,999 JPY) emerges as the most affordable option. This Class D product offers 2×300W (4Ω) output, providing significantly higher power while being substantially cheaper. The calculation is 13,999 JPY ÷ 19,170 JPY = 0.73, resulting in a final evaluation of 0.7 after rounding. However, the S-75 MK II offers features specialized for professional audio applications such as 19-inch rack mounting and balanced inputs, making it not entirely identical in application.

Reliability & Support

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Basic quality control can be expected from the Thomann brand, but detailed failure rate data is not publicly available. User reviews show generally positive evaluations regarding operational stability. Specific information about warranty periods and repair systems is limited, but support through Thomann’s sales network can be expected. However, modern support functions such as firmware updates are not incorporated. While basic durability as professional audio equipment is presumed, it cannot be considered industry-leading.

Rationality of Design Philosophy

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The application setting for small-scale fixed installations is clear, and the fanless design and incorporation of basic protection circuits are rational for this purpose. The transparent approach to technical specifications, publishing actual measurement ranges rather than idealized values, demonstrates reasonable engineering honesty. However, from a modern perspective, it appears outdated in not utilizing the possibilities of Class D technology for weight reduction and high efficiency, or digital signal processing for functional expansion. The adoption of linear transformers causes weight increase and hum noise, which is irrational given the maturity of switching power supply technology today. The necessity of existing as dedicated equipment is also questionable given the presence of higher-performance, more functional products in the same price range.

Advice

The t.amp S-75 MK II, at approximately 19,170 JPY, has certain value as a product specialized for professional audio applications. Features such as 19-inch rack mounting compatibility, balanced inputs, and bridge mode support are practical for fixed installation use. However, if pure output performance and functionality are priorities, Class D products like the AIYIMA A07 offer higher output at significantly lower cost. It could be a viable option for fixed installations in restaurants, cafes, hotels where rack mounting is required and stable operation is prioritized, but for home use or more flexible applications, we recommend considering more modern and multifunctional products. The technical specifications are standard with no major issues, but no particularly outstanding features are apparent, making it important to carefully consider the intended use before selection.

(2025.7.21)