TX-NR646 vs TX-NR656
The TX-NR656 matches the TX-NR646 on power @ 8ω (100W), bit depth (32-bit), max sample rate (384 kHz), and power @ 4ω (170W).
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AmplifiersAV ReceiversDACsDiscontinued
About the TX-NR646
The Onkyo TX-NR646 is a 7.2-channel home theater receiver designed for immersive audio and high-definition video. It delivers 170 watts per channel (6 ohms, 1 kHz, 1 channel driven) with a high-current amplifier design for authentic sound reproduction. It supports advanced multi-dimensional audio formats including Dolby Atmos (up to 5.1.2 channels) and DTS:X, providing a rich surround sound experience. The receiver features eight HDMI inputs (including one front) and two HDMI outputs, all supporting 4K UltraHD video at 60Hz with HDCP 2.2 compatibility for premium 4K content. It includes a high-grade 384 kHz/32-bit AKM DAC for high-resolution audio playback, supporting formats such as DSD 5.6 MHz and FLAC 192 kHz/24-bit. Network features include built-in Wi-Fi, Bluetooth, AirPlay, and internet music services like Spotify Connect and Pandora. The TX-NR646 also has a phono input for turntable connection, multi-zone audio capability, and room calibration via AccuEQ. Additional features include Phase-Matching Bass, A/V sync control, and a variety of analog and digital inputs for versatile connectivity. The unit is no longer in current production but remains a capable receiver for both music and home theater applications.
Specifications
Power Specifications
Amplification power output and characteristics
- Power @ 8Ω
- 100W @ 8Ω
- Power @ 4Ω
- 170W @ 4Ω
- Minimum Impedance
- 6Ω
Digital Audio
DAC capabilities and digital audio processing
- Bit Depth
- 32-bit
- Max Sample Rate
- 384 kHz
- DSD Support
- DSD128
- DAC Chip
- AKM
Connectivity
Input and output connections
- Bluetooth
- Yes
- Wi-Fi
- Yes
- Ethernet
- No
- Digital Inputs
- Optical, Coaxial
- Analog Inputs
- RCA
- Analog Outputs
- RCA
Streaming Services
Supported streaming platforms and protocols
- AirPlay
- v1
- Chromecast
- No
- Roon Ready
- No
- Spotify Connect
- Yes
- TIDAL Connect
- No
- Other Services
- Pandora, SiriusXM, Slacker, TuneIn
Physical Dimensions
Size, weight, and appearance
- Dimensions
- 435 × 173 × 346 mm (W × H × D)
- Weight
- 9.39 kg (21 lbs)
Key Specifications
Power: 100W
Specifications are community-contributed and may not be accurate or complete. Verify all details with the manufacturer before making purchasing decisions. Terms & Conditions