Yamaha RX-Z7 7.1 System Setup and Configuration

The first part of my review was conducted in the main Audioholics showcase theater room where I set up the RX-Z7 for 5.1 but biamped my front channels full range which consisted of RBH Sound T-30LSE towers that dip into the 3-ohm range to really give the amplifiers a real workout. I used the matching RBH T-1SE/R center channel and MC-6C bookshelfs on stands for the rears and one of my Velodyne DD-15's for the subwoofer channel. The transports were the Denon DVD-5910, Toshiba HD-A2 HD DVD player (yea I know, dead format) and the Yamaha MusicCAST MCX-2000 and an Epson 1080UB LCD projector.

The second part of my review was conducted in the Audioholics showcase family room which consists of all RBH Signature SE/R speakers in a 7.1 channel configuration, Axiom EP 500 subwoofer, Denon DVD-2930CI DVD player and a 56" Samsung DLP RPTV.

All of my cables were Sonicwave by Impact Acoustics / Cables to Go with the exception of my front speakers which were wired with Rivercable Starflex.  In fact Impact Acoustics was kind enough to supply me with all of their models of HDMI cables (Velocity, Sonicwave and RapidRun) to test on this receiver.

Choosing the Speaker Impedance
I tested the RX-Z7 in the "8 ohm or more" and "6 ohm" settings and as you will see in my lab tests, power was drastically reduced in the "6 ohm" setting. In NO circumstance do I ever recommend using this setting regardless of your loudspeaker impedance. This switch is put there for one purpose only – to pass UL heat dissipation requirements of driving low impedance loads. All it does is limit the output voltage to the amplifiers so that they clip at lower power and thus under their test condition, the receiver generates less heat.

Auto Setup Via YPAO

I've covered YPAO extensively in other Yamaha reviews, most recently my review of the RX-Z11. As a general overview however, YPAO automatically checks and calibrates the following parameters:

• Wiring
• Distance
• Size
• Equalization (manual, flat, front, natural, "through" which means bypass)
• Level
• Angle

Like the RX-Z11, the RX-Z7 features Yamaha's latest YPAO iteration of doing standing wave correction via a Frisbee looking device that you place the YPAO microphone on at each of the three legs in the primary calibration location. It would be more useful if YPAO would run this part of the calibration right after it takes the measurements for the primary seat so you don't have to hassle repositioning the microphone in that location after you've run the multi point calibration suite (up to 8 locations). YPAO does some low frequency equalization down to 32 Hz for all channels with roughly 1/6^th octave resolution. It offers a manual adjustment mode with a variable Q of .5 to 10.08 and Gain: +6 to -20dB with up to up to 3 bands per channel.

YPAO Calibration Results

Given my past experience with YPAO, I was honestly not going to test YPAO but was pleasantly surprised that the calibration results this time exceeded my expectations. Either there was perfect celestial alignment in the galaxy or Yamaha tweaked YPAO performance, or I just got lucky that YPAO nailed speaker level, distance (including the subwoofer) and size correctly. The only tweak I had to make was the center channel crossover which I lowered from 100Hz to 80Hz. I only used a 3 point calibration and kept the mic in relatively close proximity to the main listening position. I have found that keeping the sample points closely spaced towards the primary one or two seats does produce more consistent and usable results in virtually all auto calibration systems.

YPAO Low Frequency Calibration Results

YPAO didn't drastically change the shape of the measurement curve as much as it subtly lowered some problematic areas most notably 40-50Hz and 90-120Hz ranges. The Left graph above shows the calibration results for the mains + subwoofer with/without YPAO while the right graph shows the subwoofer channels only. YPAO lowered the subwoofer amplitude about -2dB below 38Hz and an additional 1dB from 38Hz to about 60Hz. To date the only auto correction system I've experimented with that significantly changes (not always for the better) system bass response is Audyssey.

Sonic Results of YPAO

One thing I've learned about Yamaha is that if you complain about something enough times in reviews, they eventually listen. Such is the case with this receiver and the RX-Z11 when it comes to selecting different PEQ settings simultaneously for all channels on the fly so you can instantaneously here the sonic results. It was a real delight to compare the different PEQ settings which as I previously mentioned weren't offensive sounding to me like that have been in the past. I found "Natural" mode slightly tightened up the low end with a slight reduction in overall impact. It slightly dulled the top end but did a good job of preserving the soundstage while also anchoring the vocals towards the midpoint of my main speakers. It wasn't quite as focused as the results I got from Pioneer's MCACC system, but it also didn't drastically reduce the soundstage like I heard with MCACC. "Flat" mode extended the treble response, perhaps sometimes a tad too much depending on source material but overall this was my preferred EQ setting.

Manual Calibration

After YPAO was completed, I did some preliminary listening tests and decided to manually tweak trim levels (0.5dB here or there for the main channels and about 2dB lower for the sub). I also went into the bass management menu and engaged "Bass Out" for the main channels + the subwoofers. The manual EQ mode is a helpful tool to further smooth out bass response even though YPAO doesn't quite have enough resolution. It's still good enough to fine tune low Q problem areas such as bumps or to a minor extent suckouts. Simply copy over the curve of your choice to the PEQ data copy and go in to do your edits. If you don't like them, you can always restore the original calibration results and start all over again.

Editorial Note for PEQ Editing

For those inclined to do some fine tuning of your systems frequency response and an available RTA analyzer to measure before and after results, here is a quick reference on how to use the editing features of YPAO and to calculate the Q.

· Select freq/gain to choose the center frequency

· Select band/gain to set the Q and gain as needed

How to Calculating Q:

To calculate Q, use fc / BW where fc = center frequency and BW - bandwidth

Bass Management

As I have come to expect with all top end Yamaha A/V receivers since they abandoned their abominable 90Hz fixed crossover setting, bass management of this receiver was excellent, Yamaha offers a variable crossover point from 40Hz to 200 Hz and +- phase adjustment for the subwoofer(s) so you can determine the best setting without having to go behind your subwoofer(s) to change it. There is also a "both" setting for the bass output so you can still have your subwoofer active for 2CH sources even if your main speakers are set to large. Please note however that "Pure Direct" and "Stereo Direct" modes bypass the bass management altogether and will NOT send signal to the subwoofer for 2CH sources regardless of speaker settings. In this case, either don't use "Pure Direct" or disable the "auto" setting for stereo direct mode in the OSD to engage the DSP and bass management.

As was the case with the RX-Z11, the RX-Z7 provides for variable crossover settings per speaker group (ie. Mains, Center, Surrounds but doesn't give you a choice for the subwoofer crossover which I found through my testing to be dependent on the main channel crossover setting when listening to 2CH sources in multi channel modes such as PLIIx Music or DSP programs. Thus I highly recommend you keep each speaker groups crossover setting within 20Hz to ensure a more optimal integration with the subwoofer during all playback modes.

I also noted that if you set the main channels to "small", the RX-Z7 still allows you to set the center and surround channels to "large". I would have preferred Yamaha to automatically set all speakers to "small" if the mains were set "small". But, since they didn't, pay extra attention to this when configuring your bass management settings.

The crossovers worked as expected for a THX Ultra2 certified receiver (despite the RX-Z7 is not THX certified) as indicated by the 12dB/oct High Pass Filter (HPF) slopes on speakers set small and 24dB/oct Low Pass Filter (LPF) slopes on the subwoofer output which I measured with my Audio Precision SYS 2722 Audio Analyzer.