Yamaha - A-S801 Integrated Amplifier

The only integrated amplifier in Yamaha’s A-S range with a proper built-in DAC — an ESS Sabre ES9010K2M on a USB Type-B input, handling native DSD and PCM to 384 kHz — wrapped around the same 100-watt output stage as the A-S701.

This is the model to buy if a computer is one of your sources. The USB Type-B input runs into a 32-bit ESS Technology ES9010K2M Sabre converter, which Yamaha names explicitly — the only model in the range for which it does. Over USB it accepts native DSD at 2.8224 and 5.6448 MHz and PCM up to 384 kHz at 32-bit on Windows or 24-bit on Mac. The optical and coaxial inputs feed the same converter but are PCM only, to 192 kHz, with no DSD. The analogue CD, LINE and PHONO inputs bypass the DAC entirely.

ToP-ART, Yamaha’s Total Purity Audio Reproduction Technology, is a layout philosophy rather than a circuit: the left and right channels are laid out as mirror images and the signal takes the shortest, straightest route from input to output, on the reasoning that a shorter path picks up less noise and adds less distortion. The ART (Anti-Resonance and Tough) Base is the mechanical half of the same idea — a stiffened bottom chassis with a solid centre bar that damps vibration before it reaches the circuit boards. Both are real, named engineering choices; Yamaha publishes no measurement isolating what either contributes.

Be clear about what the extra money buys. The A-S801 is rated at 100 watts into 8 ohms — identical to the A-S701 below it. It is not a more powerful amplifier. The differences are the USB DAC, a heavier double-bottom chassis built on a 1 mm iron plate, larger 12,000 µF block capacitors, and about two pounds of extra mass. The phono stage is still moving-magnet only and there are still no level meters. Unusually for the range, this model has no MAIN IN or PRE OUT at all — Yamaha’s manual confirms their absence, so the A-S801 cannot be split into pre and power sections the way the A-S1200 and A-S2200 can.

Pure Direct routes the signal by the shortest internal path available, bypassing the buffer amplifier and the tone, loudness and balance controls. The continuously variable loudness control does the opposite job when you want it: because hearing loses sensitivity at the frequency extremes as level drops, it dials in a variable amount of bass and treble lift as you turn down, rather than the single fixed curve a simple loudness switch gives you.

Features

• ESS Technology ES9010K2M 32-bit Sabre DAC on a USB Type-B input — the only A-S integrated with a Yamaha-named converter
• Native DSD 2.8 and 5.6 MHz, PCM to 384 kHz / 32-bit over USB
• 100 W + 100 W into 8 ohms, 20 Hz – 20 kHz at 0.019% THD
• Double-bottom ART Base chassis with 1 mm iron damping plate and solid centre bar
• 12,000 µF block capacitors and a custom power transformer
• Moving-magnet phono input
• Pure Direct and CD Direct Amplification modes
• Continuously variable loudness control, bass, treble and balance
• Subwoofer output
• Two pairs of gold-plated binding posts with A / B / A+B bi-wiring
• Available in black or silver

Specifications

• Type: Two-channel integrated amplifier with built-in USB DAC
• DAC: ESS Technology ES9010K2M, 32-bit Sabre. Named by Yamaha for this model
• USB input: Type B, USB 2.0. Native DSD 2.8224 and 5.6448 MHz; PCM up to 384 / 352.8 / 192 / 176.4 / 96 / 88.2 / 48 / 44.1 kHz at 32-bit (Windows) or 24-bit (Mac)
• Optical and coaxial inputs: PCM only, up to 192 / 176.4 / 96 / 88.2 / 48 / 44.1 / 32 kHz. No DSD over these inputs
• Rated power output (8 ohms): 100 W + 100 W, 20 Hz – 20 kHz, 0.019% THD
• Rated power output (6 ohms): 120 W + 120 W (owner’s manual). Yamaha publishes no distortion or bandwidth condition with this figure, unlike the 8-ohm rating above
• Dynamic power (IHF): 140 W into 8 ohms, 170 W into 6 ohms, 220 W into 4 ohms, 290 W into 2 ohms, per channel
• Power bandwidth: 10 Hz – 50 kHz, 0.04% THD, 50 W into 8 ohms
• Frequency response: 10 Hz – 100 kHz, ±1.0 dB (Pure Direct); 20 Hz – 20 kHz, 0 ±0.5 dB (CD input)
• Total harmonic distortion: 0.019% or less, CD input to speakers, 20 Hz – 20 kHz at 50 W into 8 ohms
• Signal-to-noise ratio: 99 dB or more (CD, Pure Direct on); 104 dB or more with CD Direct Amplification. Two different circuit conditions, not interchangeable
• Damping factor: 240 (Speakers A, 1 kHz, 8 ohms)
• Phono stage: Moving magnet only, 3.0 mV / 47 kilohms
• RIAA deviation: Not published
• Analogue inputs: PHONO (MM), CD, LINE
• Outputs: Speakers A and B, subwoofer out, REC OUT, DC OUT, headphones
• Preamp out / main in: None. Yamaha’s owner’s manual confirms this model has neither MAIN IN nor PRE OUT; it uses a record-out-only architecture and cannot be used as a separate preamplifier or power amplifier
• Balanced XLR input: No
• Headphone output: 470 mV / 470 ohms (CD input, 1 kHz, 200 mV, 8 ohms)
• Tone controls: Bass and treble. Balance control fitted
• Loudness: Continuously variable
• Level meters: No
• Subwoofer output: Yes
• Speaker terminals: Two pairs, gold-plated binding posts, A / B / A+B bi-wiring
• Dimensions (W×H×D): 17-1/8″ × 6″ × 15-1/4″ (435 × 152 × 387 mm)
• Weight: 26.7 lb (12.1 kg)
• Power consumption: 270 W; 0.5 W standby
• Finishes: Black and Silver (A-S801BL and A-S801SL)
• Country of manufacture: Not published. Yamaha prints no country-of-manufacture statement on this model’s US product pages, specification tables or owner’s manual. The only geographic reference in Yamaha’s own documentation is the corporate head-office address in Hamamatsu, Japan, which is a company address and not a manufacturing statement. Third-party retailers and reviewers often assert “made in Japan” for this model — Yamaha does not.
• Warranty: Two years, parts and labour, under Yamaha Corporation of America’s general A/V Products limited warranty, which is the document Yamaha’s warranty index links for this class of product. Yamaha states that warranty registration is not required for coverage. The warranty is enforceable only by the original purchaser and is not transferable. The owner pays shipping to the service centre; Yamaha covers return shipping on a covered repair.