Onkyo TX-RZ70 11.2CH AV Receiver Bench Test Results!

Onkyo TX-RZ70 Introduction

The Onkyo TX-RZ70 ($2,800) is a THX certified flagship 11.2CH AV receiver boasting 140 watts/ch x 11, 7 8K HDMI inputs, Dolby Atmos, DTS:X, Auro 3D, IMAX Enhanced and Dirac live (standard) with upgrade path to Dirac Live Bass Control. The Onkyo shares a similar platform to the Integra DRX-8.4 ($3,200) and Pioneer VSX-LX805 ($2,999) with differentiating features between the 3 brands that may appeal to different buyers and installation applications. All three AVRs share virtually identical power amp sections and utilize 2x ESS9026Pro 8CH DACs. The Pioneer and Integra models feature one pair of XLR inputs, while the Integra has XLR outputs for the front LCRs and subs, and the Pioneer has XLR outputs for the front LR outputs only. All three models feature dual independent subwoofer outputs. Additionally, the Integra and Pioneer models have two sets of paralleled sub outs to connect up to four subwoofers. The Integra and Onkyo AVRs support THX Select while the Pioneer does not.

This bench test report focuses on the Onkyo TX-RZ70, examining its frequency response, signal-to-noise ratio (SNR), bass management, distortion, and power delivery for up to 7 of the 11 channels driven under various load conditions. Similar bench test results can be expected for the Integra and Pioneer counterparts, as all three models share similar DNA.

Note: All measurements were conducted using our Audio Precision APx585 8 Channel HDMI Audio Analyzer.  The Onkyo TX-RZ70 was defaulted to high-impedance (High Z) mode (6-ohms or more) and ECO Off unless otherwise stated.

For more information about how we measure power amplifiers, please see:

Basic Amplifier Measurement Techniques

Onkyo TX-RZ70 11.2CH AV Receiver Bench Test Results!

Onkyo TX-RZ70 Preamplifier Measurements

The TX-RZ70 preouts are able to deliver  about 4Vrms unclipped from the multi-ch preamp outputs which is more than 2X voltage drive needed to make most external amplifiers reach full unclipped power.  The main channels had the lowest distortion as can be seen in the graph below. Preamp mode made a slight improvement in THD+N for the surround channels.

The Onkyo TX-RZ70 measured ruler flat from 10Hz to 50Khz (-1.7dB @ 85kHz).

 

Onkyo TX-RZ70 Frequency Response Analog Pure Direct

 

Onkyo TX-RZ70 SINAD vs Vrms Analog Preamp

The TX-RZ70 produced very low distortion of 99dB SINAD (.001% THD+N) for the main channels and 86dB SINAD (.005% THD+N) for the surround channels via the multi-ch preouts.

Note: While this distortion difference is measurable between channel groups, it’s unlikely to be audible.

As shown with the SINAD vs Vrms graph prior, the preouts of the TX-RZ70 have plenty of clean drive (3-4Vrms).

Onkyo TX-RZ70 Vsweep vs Distortion (HDMI In, Preout)

Note: The preamp disconnect mode can be selected for the main channels or all channels. It should be used if you are using external amplification on those channels since it disconnects the preamp signal to the power amp section, which is designed to drive the internal amplifiers into clipping around 1.6 Vrms. I personally prefer not driving an amplifier into clipping, even if there is no load attached to it.

Onkyo TX-RZ70 FFT Preout (2Vrms out, 0dbFS input)

With a digital full-scale input (0dBFS) and the volume adjusted to 2Vrms from the preamp outputs, the FFT looks very good with the 3rd order harmonic being 94dB below the 1kHz fundamental.  There was no appreciable hum or power supply noise present.

Onkyo TX-RZ70 SNR Analog Preout

Note: Ignore CH 4 which is the subwoofer channel in this case.

The Signal to Noise Ratio from the analog preouts of the Onkyo TX-RZ70 is excellent. With a 0dBFs input and 2Vrms output, I measured about 112 dB for ALL the channels regardless if I engaged preamp mode, pure direct or regular multi-ch. Anything above 100dB at 2Vrms is considered “quiet” in my book. The Onkyo is dead silent and will make for an excellent preamp/processor if you decide to power up in the future with a multi-channel amplifier.

Onkyo TX-RZ70 Bass Management

With all channels set small, the HPF is correct 12dB/oct and LPF is correct 24dB/oct. This is what you would get from a THX certified product and is textbook good performance.

Note: The bass management calculator in the DSP has a 48kHz limitation and downsamples high resolution sources when engaged. Some AVRs from Yamaha and Denon don’t have this limitation but some high end processors like the $24k Storm Audio ISP processor also has a similar limitation. It’s not something to be too concerned about in my opinion.

 

Onkyo TX-RZ70 Bass Management (fc = 80Hz)

Onkyo’s Standing Wave manual EQ function is a bit disappointing. The TX-RZ70 only provides preadjusted set points that you can select. The Q of their prescribed filters is too low to serve as an effective calibration tool in most cases. To make matters worse, it applies the filter to ALL channels as there is no way to select channel groups or just the subwoofers.

PEQ filters are supposed to have adjustable frequency (Hz), Q (width) and amplitude settings (+-dB). Having the adjustability allows a calibrator to dial in the exact frequencies of the problematic room modes to customize filters to reduce or eliminate them. As you can see below, I selected 60Hz and applied a cut of 10dB. 

The Q appears to be around 2 based on: Q = fc / (f2-f1) or 60 / (80-50) = 2.

Onkyo TX-RZ70 PEQ Manual Filter Engaged

Onkyo TX-RZ70 Filter DAC Settings

Buried in the menus is a section where you can select the filter response type for the DAC. The effects of the various settings are most pronounced with Fs = 44.1kHz (CD sampling rate) and diminish as you increase sampling rate. Based on my measurements, I concluded that Filter: Auto = Sharp = Short while   Slow starts to roll off below 20kHz. I would recommend leaving this on “auto” for most cases.

 

Onkyo TX-RZ70 Frequency Response of Various Filter Settings (Fs= 44.1kHz)

 

Onkyo TX-RZ70 FFT Noise Spectrum (fs = 44.1kHz)

 

Onkyo TX-RZ70 FFT Noise Spectrum - fs = 96kHz (red) & 192kHz (brown)

With a 44.1kHz digital input, I checked the stopband rolloff and found it to have a smooth rolloff below ½ Nyquist. The noise spectra showed a little weirdness above 45kHz but it’s down in the weeds at -110dB and inconsequential. With the sampling rate increased to 96kHz, out of band noise was excellent at -130dB.

Onkyo TX-RZ70 Power Measurements

Using our Audio Precision APx585 8-channel HDMI analyzer, we conducted a full barrage of multi-channel amplifier tests on Onkyo TX-RZ70 per our Amplifier Measurement Protocol. We tested power using three methods all of which were taken at < 0.1% THD + N:

• Continuous Full Power Bandwidth (CFP-BW) from 20Hz to 20kHz into 8 and 4-ohm loads (up to two-channels)

• 1kHz Power Sweep vs. Distortion (1kHz PSweep) - popularized by the print magazines, this is an instantaneous power vs. distortion test at 1kHz. The problem with this test is it often masks slew-related and/or frequency response problems some amplifiers exhibit at the frequency extremes, and thus inflates the measured power results. It does provide an instant gratification number for consumers to argue over on the forums, so we are now incorporating this test to please the masses.

• Dynamic PWR - 1kHz CEA-2006 Burst Method testing. This is a dynamic power measurement adopted from the car industry similar to IHF method only a bit more difficult for an amplifier and more representative of real musical content.

Keep in mind most review publications don't do continuous power measurements and they usually publish power measurements into clipping at 1% THD + N. Our measurements are very conservative as we use a dedicated 20A line with no Variac to regulate line voltage.  We constantly monitor the line to ensure it never drops more than 2Vrms from nominal, which in our case was 120Vrms.  

For more info on amplifier measurements, see:  The All Channels Driven (ACD) Test

Onkyo TX-RZ70 Frequency Response @ Speaker Output

 

Onkyo TX-RZ70 CFP-BW – (2CH) – 4 ohms

The TX-RZ70 exhibited ruler flat frequency response from the power amp all the way out to 48kHz with a -3dB pt of 78kHz. With two-channels driven, the 140 watt/ch rated TX-RZ70 delivered almost 170 watts/ch for full bandwidth 20Hz to 20kHz at under 1% THD+N into 8 ohm load. Under similar test conditions for 4 ohms, the TX-RZ70 delivered 265 watts/ch 2CH driven at 0.05% THD+N. I couldn’t test it at a higher level without tripping the protection circuits.

Onkyo TX-RZ70 SINAD vs Power (2CH) – 8 ohms

Distortion is low for the amp section of the TX-RZ70 measuring 85dB SINAD (.005% THD+N) up to at 50 watts/ch. That’s excellent!

For 1kHz sweep testing, the TX-RZ70 delivered 161 watts/ch at 0.1% THD+N and 178 watts/ch at 1% THD+N into 8-ohms two channels driven.

Onkyo TX-RZ70 1kHz PSweep (7CH) - 8 ohms

The TX-RZ70 was able to muster 118 watts/ch at 0.1% THD+N and 133 watts/ch at 1% THD+N into 8-ohms with seven channels driven. By comparison, the costlier Marantz SR8015 tested 92 watts/ch @ .01% THD+N and 101 watts/ch at 1% with seven channels driven under similar test conditions.

Onkyo TX-RZ70 1kHz PSweep (2CH) – 4 ohms

The TX-RZ70 was able to belt out 266 watts/ch at 0.1% THD+N and 299 watts/ch at 1% THD+N into 4-ohms with both channels driven. This beats the Marantz SR8015 which tested at 229 watts/ch @ .01% THD+N and 251 watts/ch at 1% under similar test conditions.

Hold the Nannies Please

The Onkyo TX-RZ70 put out some impressive power numbers IF you disable the dreaded nannies (ie. Eco mode and Low Impedance switch). If you leave the receiver set to Eco Auto or Off and the default “6ohm or more” setting on the impedance switch, this will NOT affect the performance of your unit.

Onkyo TX-RZ70 Impedance Switch Psweep Comparison

In the 4-ohm setting, the Onkyo TX-RZ70 was only able to deliver 29 watts/ch at 0.1% THD+N and 32 watts/ch at 1% THD+N for 2CH driven at 8 ohms. When testing at 4 ohms, the power modestly increased to 47 watts/ch at 0.1% THD+N and 54 watts/ch at 1% THD+N for 2CH driven.

Editorial Note: Impedance Selector Switch – No matter how tempted you may be to do so, we DO NOT recommend changing the default "6 ohm min" impedance setting of ANY AV receiver, especially this unit. All this does is starve your speakers of power, simply so the manufacturer can get 4-ohm certification (at a reduced power level) without making the receiver get too hot during their power tests. We have tested this 'feature' on virtually every receiver that has offered it in the past, and the results were always the same: the low impedance setting significantly robs your speakers of power.

For more information, see:  Setting the AV Receiver Impedance Switch

Onkyo TX-RZ70 Dynamic (2CH) Power Test - 4 ohms

The Onkyo TX-RZ70 wins a bass ass award for its impressive CEA 2006 short dynamic burst tests results by delivering about 213 watts/ch for 8 ohms and 370 watts/ch with 2CH driven at 4 ohms and over 180 watts/ch with 7CH driven at 8 ohms. If you compare the 140 watts/ch rating to dynamic power, we see about 1.8dB of dynamic headroom. That's impressive! What is NOT impressive is if the impedance switch is set to 4-ohms, this power dropped to 59 watts/ch for 2CH driven into a 4-ohm load. Do NOT mess with the impedance switch under ANY circumstance!

Onkyo TX-RZ70 Power Measurement Table

Onkyo TX-RZ70 Power Measurement Table

Onkyo TX-RZ70 CH-CH Crosstalk (1CH, Undriven) @ 1 watt

The channel-channel crosstalk was excellent for a multi-ch receiver, especially one packing 11 channels of amplification. On the preamp side, CH-CH isolation was about -85dB at 20kHz which is excellent.

On the amplifier side, with ACD except for the one under test, the TX-RZ70 provided > -50dB of CH-CH isolation out to 20kHz. This is a decent figure but not as good as we’ve seen on competitor AVRs.

Note: I wasn’t able to sweep all 7 channels on this particular test due to EDID compatibility issues with my test gear.  

Onkyo TX-RZ70 Power Consumption

Aside from the sheer mass of this unit, the back panel of the Onkyo TX-RZ70 gives you some indication that it is indeed a very powerful AV receiver. You can see this with the rating of 1095 watts, though let me remind you of the article and YouTube video we did on the topic of AV receiver power consumption that unless the unit states “Max Power Consumption,” you can safely bet it is NOT. If you recall how I explained this before, this power consumption estimate is usually based on ALL channels driven at 1/8th power, which is where a linear amp is least efficient (20% typical). So if we take 1/8 * (140) * 11 and then account for efficiency, you’re looking at about 963 watts. Add on another 100 watts or so for HDMI and DSP processing, and you get the 1095 power consumption figure stamped on the back of the unit. Despite the 1095-watt back panel power rating, my power measurements show that driving 7 channels at 130 watts per channel (130 watts x 7 / 0.6) equals 1516 watts. Adding processing power, the maximum power consumption is closer to 1600 watts!

On the topic of power consumption, it is interesting to note that the 150 watts/ch-rated Integra DRX-8.4 and Pioneer VSX-LX805 counterparts all have the same 1095-watt power consumption stamped on the back panel as the Onkyo TX-RZ70.

Onkyo TX-RZ70 Summary

The Onkyo TX-RZ70 proved to be a true powerhouse of an AV receiver and certainly the top dog in its price class and slightly beyond. I tested the amp section of this AVR rigorously, and it rewarded me with great sustained power delivery that exceeded its power ratings. During high-power sweeps, variable speed fans activated but were almost imperceptible just a couple of feet away in a quiet room. I’m pleased to see Onkyo addressed the issue we discovered in prior models tested (including Integra) that would go into a low power mode after fault protection occurred, which could only be reset by unplugging the unit from the wall rather than a simple power toggle. Instead, if a fault condition occurs with the TX-RZ70, the unit checks the amplifier channels one by one when turned back on. It takes a couple of minutes, but it is probably a good measure to help troubleshoot fault conditions beyond overdriving in a bench test scenario.

Onkyo vs Integra vs Pioneer

The Onkyo TX-RZ70 provides flagship-level performance in almost all measurement scenarios and has the most powerful amplifier section in its price class. This is the type of performance I’ve come to revere from the brand decades ago, and I’m glad to see Onkyo returning to its heritage, making it a true contender in a very competitive marketplace. You can expect similar performance from the Integra DRX-8.4 ($3,200) and Pioneer VSX-LX805 ($2,999), as these receivers all share a common platform with a few differentiating features. Though, it’s odd that Onkyo rates the TX-RZ70 at 140 watts per channel x 11, while its Integra and Pioneer counterparts are rated at 150 watts per channel x 11 despite using identical power sections and exact same power consumption figures on their respective backpanels. Perhaps it’s a specmanship error or deliberate differentiation of the brands? In either case, I’m happy to see that Onkyo, Integra, and Pioneer have put serious attention into the amplifier sections of these AVRs and have dropped the subpar Class D ICE modules that previous models used, which simply could not drive 4-ohm loads at high power very well, as I found with the Pioneer SC-07. If I was on the market for an 11.2CH AV receiver for around $3k, the Onkyo TX-RZ70 would be my top choice especially if you have power hungry speakers or an insatiable appetite for achieving reference levels in your home theater system.

Stay tuned for our full written review with listening tests and tips on how to get the most out of your Onkyo TZ-RZ70.....