Onkyo TX-8470 Review

The TX-8470 exudes the spirit that characterized Onkyo in the last century. Everything looks like before, but inside a small technical revolution took place: The stereo receiver combines streaming with AV flair.

by Stefan Schickedanz

After its temporary end in 2020, the audio specialist founded in Osaka in 1917 returned to the hi-fi stage.

After some economic turmoil, the Japanese company landed in 2021 with Voxx International—a company listed on the NASDAQ technology exchange, which also includes the German speaker manufacturer Magnat and the American speaker maker Klipsch. Despite all near-death experiences of the traditional brand, the TX-8470 stereo network receiver shows the practicality and functionally influenced design that made Onkyo great. Some clever solutions have even been added.

One shows a heart for testers: While we in our profession are usually at odds with user manuals, they can sometimes get lost on their way through various departments in a large editorial office. Then you can neither scan the code for the expected app nor search for its name. This can cause frustration with manufacturers that have more than one app or third-party solutions. When you turn on the receiver, the large display equipped with Onkyo-typical green light segments displays “Download Onkyo Controller App” in scrolling text.

The aforementioned app (see box on this page) serves to integrate the TX-8470 into multi-room systems and for basic settings such as tone control or volume adjustment. The latter is better done with the included remote control, and as far as streaming control is concerned, Onkyo relies on the generic apps of the streaming services or the music players of smartphones. For this purpose, the TX-8470 supports both AirPlay and Chromecast.

Tidal, Deezer, and Spotify are integrated. In addition to its streaming capabilities, the Roon-compatible stereo receiver relies on integrated tuners for FM and DAB+ as well as a whole range of analog and digital inputs. Standing out are the HDMI connections that not so long ago were only found on AV receivers. There are four inputs and one output with Audio Return Channel (ARC). Video images can be passed through with 8K resolution.

As far as outputs are concerned, the TX-8470 is also well equipped: There are two preamplifier outputs and a subwoofer output. In addition, there are two pairs of speaker connections. The screw terminals equipped with gold-plated contacts appear solid, but the sheet metal of the rear panel is so thin that they move noticeably when handling thick cables. This is only a minor cosmetic flaw that is irrelevant in practice. However, it shows exemplarily how tightly product planners have to calculate today with such comparatively inexpensively priced equipment marvels.

The digital heart of the Onkyo is the AKM AK4452, a stereo DAC with 32-bit/768 kHz resolution. This means it is also equipped for DSD256, i.e., 11.2 MHz. Despite this performance in the digital area, vinyl enthusiasts are not neglected with the integrated amplifier: The TX-8470 amplifies not only MM systems but also the signals of MC cartridges. However, the balancing act between high-frequency digital circuits and the sensitive MC amplifier with its high gain factor is reflected in the measurements (see lab box). Regarding signal-to-noise ratio, the combination of highly sensitive analog technology and streaming like LAN cable, WLAN, or Bluetooth connection takes its toll.

Economical with power, not with strength

Onkyo uses two high-current Class G amplifiers with low negative feedback (NFB) in the TX-8470 and promises high transparency and musicality compared to Class AB amplifiers with increased efficiency. Class G amps use multiple supply voltages. At low power output, the amplifier operates with a lower supply voltage to reduce power consumption. At higher power requirements, the amplifier switches to a higher supply voltage. This trick reduces power loss and the associated heat dissipation. At the same time, it ensures low thermally induced distortion.

Pulls out all transparency stops

In the listening test, the TX-8470 proved to be an outright clean machine. It impressed with excellent transparency and high detail resolution. In addition, a very precise focus and the very deep, precise bass contributed to the extremely positive overall picture. The dynamic reserves also left absolutely nothing to be desired. However, you have to turn the endlessly rotating volume knob diligently to unleash them.

Turning is also required when using the Onkyo Controller App. The somewhat nested solution is not necessarily practical but original because it imitates a rotary knob. For its class, the playback kicked remarkably well even with AAC’s data diet via AirPlay. The spacious soundstage and fine detail resolution made live recordings—with all the audience’s emotions—a feast, especially in hi-res, but still very engaging even with lower data rates.