Ресиверы — Yamaha RX-A4A

The RX-A4A is a 7.2-channel AV receiver in Yamaha's AVENTAGE series, placed above the RX-A2A and below the 9.2-channel RX-A6A and the 11.2-channel RX-A8A. It combines 8K-capable HDMI, Dolby Atmos and DTS:X decoding, MusicCast multi-room streaming and a turntable input in a single box, and it is the lowest AVENTAGE model that carries Yamaha's Surround AI processing.

Key specs that matter

Yamaha rates the amplifier section at 110 W per channel into 8 ohm from 20 Hz to 20 kHz with two channels driven at 0.06% THD, and at 135 W into 8 ohm at 1 kHz with one channel driven at 0.9% THD. The HDMI board offers seven inputs and three outputs to HDMI 2.1 and HDCP 2.3, with 4K120, 8K60 and 40 Gbps pass-through, eARC, upscaling to 8K, Dolby Vision, HDR10+, VRR and ALLM. Other inputs are two optical, one coaxial, four analog and a phono stage, and there are 7.2-channel pre outs, a headphone jack and two 12 V trigger outputs. The network player handles FLAC to 384 kHz and 24-bit, WAV and AIFF to 384 kHz and 32-bit, and DSD to 11.2 MHz. Wi-Fi works on 2.4 and 5 GHz, and Bluetooth supports SBC and AAC. The receiver measures 435 x 191 x 442 mm with the antennas down and weighs 16.2 kg, and standby consumption is below 0.4 W.

Engineering and use context

Decoding and sound field work run on a Qualcomm QCS407 with 64-bit processing. Surround AI analyses dialogue, background music, ambient sounds and effects in each scene and adjusts the surround field in real time, and Cinema DSP HD3 offers 24 programs, able to build up to 11.1 channels from a 7.1 layout when front height speakers are connected. Dolby Atmos Height Virtualization can simulate overhead channels without ceiling speakers. Digital-to-analog conversion uses an ESS SABRE ES9007S rated at up to 120 dB of dynamic range. A newly designed amplifier circuit targets a high slew rate, and the internal layout is symmetrical to keep signal paths on each board short. An H-cross frame stiffens the chassis, and the A.R.T. Wedge, a fifth foot placed centrally under the front edge, damps vibration from the transformer, power transistors and heat sinks. The Zone 2 output can carry the same or different content via speaker terminals, pre outs or HDMI, and the receiver is Roon Tested and certified to work with Sonos through a Sonos Port.

Pairing

The seven channels can serve a 5.1 system with two overhead or Atmos elevation speakers, and bi-amp wiring of the front pair is listed among the features. Owners who want more headroom can drive the front channels from an external power amplifier through the pre outs, and vinyl owners can plug a deck into the phono terminals.

Alternatives

The Yamaha RX-A6A is the 9.2-channel AVENTAGE receiver with 150 W per channel, Auro-3D decoding, XLR inputs and Zone 2, 3 and 4 outputs.