VSX-82TXS Video Processing and MCACC

Video processing is really what a lot of people are concerned about at this time. As HDMI becomes more and more common, we are going to see a lot of the web of A/V connections reduced to just a few wires. For now, most of us have a mishmash of components that have different output capabilities. What we want is something that takes all that and transfers it all to component or HDMI so that we are only having to run a single wire to the display. This simplifies our lives as the video is automatically switched when you change sources on your receiver. The VSX-82TXS is supposed to be able to convert any incoming signal to all the different monitor outs.

In the course of reviewing this receiver I noticed some visual artifacts on the display that seemed static - some vertical lines that ran across the screen mostly at the bottom and top of the display. Unfortunately, I had a display in for review the same time I was reviewing the 82TXS so it took me a while to identify the problem. I thought I had a bad monitor until I ran a 6.75 MHz test and the display failed. For those of you that don't know, this is a 480p test. There is no way that display should have failed (it was 720p capable). So, off I went to test the connections and discover the cause. Eventually, I figured out that when I turned the video conversion "Off" so that all the unit was doing was switching, it passed the 6.5 MHz test and the artifacts went away. On a whim, I went back and sent the unit a 480i signal. With a 480i signal, the unit passed the 6.75 MHz test. It seems that sending the unit a progressive signal caused it to fail the test.

But that was not the end of the saga. Buried deep in the AV Parameter menu is an option called Resolution. You can select Pure , 480p , 720p , or 1080i depending on your display capabilities (the default is Pure) . Once I selected 720p , I found that the unit now passed the 6.75 MHz test on both component and HDMI. But I still noticed some visual artifacts on the HDMI output. If I sent a 480i signal, I noticed the visual artifacts on both component and HDMI. I've informed Pioneer of my findings and will report back once they respond.

MCACC Automatic Calibration

I was very excited to use the MCACC automatic calibration system. I wasn't sure exactly what it could do but I could tell from the menus that it seemed to be highly user configurable. While I don't have the equipment on hand to check the accuracy of the system I could compare my manual settings to the MCACC settings. When implementing the MCACC, I set the supplied microphone on a tripod at ear level at the sweet spot. The mic plugged into the front of the unit and had a long enough cord to reach my prime listening area two times over. I did the testing at night when the house was the quietest and turned the AC off (a big sacrifice in Florida during summer). I left the room and only popped in to hit OK when prompted:

Table 1: Speaker Settings

It apparently came to the conclusion that my fronts and surrounds were Large. This is a common occurrence on auto calibration systems and is a result of the system factoring in a reasonable low frequency extension for main speakers that isn't 20Hz (typically 50Hz will net you a "Large" setting). When I checked the EQ curve it was trying to boost 63Hz by 8dB or more. Luckily both the distances and the levels were all fairly close save the subwoofer distance. This is very common as the on-board DSP in many receivers cannot correctly capture the information needed to correctly place a subwoofer. In addition, many subs with DSP andor undefeatable crossovers also cause difficulties. Your best bet is to use common sense and reference the subwoofer distance based on your main speakers.

The way to go with the MCACC is to run it at ALL which sets the speaker levels and distances (especially handy if you don't have an SPL meter). Go back and modify the distances and types. Then you can rerun it using only the Acoustical Cal EQ Pro to make sure that the settings aren't too far off because of incorrect speaker size or distance. It won't overwrite your speaker settings but it will overwrite your EQ settings.

Table 2: EQ Settings

Table 2 shows the EQ setting when I set the speaker levelsdistance (labeled Me) and when the MCACC set the distance/levels (labeled Pio). I did all this to show you what you probably wouldn't have believed if I had just stated it. Even with the wrong speaker sizes the two are pretty close. I noticed that at 125Hz and 250Hz the Pio setting is quite a bit lower than the setting achieved when I set the speaker type, level, and distance. Other than that, though, they are pretty close.

I wanted to see if I could hear the difference between these two and more importantly, compared to a baseline with the EQ off. I listened to some music at first and I definitely heard a difference (described later) but then I got the bright idea of trying out my Avia disc. Under the Audio Calibrations menu I looked at the Verification/Evaluation tones. I went ahead and chose the Wideband Pink, 5 Channel Pan and the 150 HighPass Pink, 5 Channel Pan. I didn't think it was fair to look at any of the low frequency sweeps as the MCACC doesn't really do anything to the sub. As the test tone circled around the room, it quickly became evident that the EQ was doing something. With the EQ off I perceived a much fuller sound with substantially more midrange. The EQ setting based on my speaker settings had reduced midrange but not as much as the MCACC only EQ. Now, is this a bad thing? Not necessarily. If I have a midrange bump based on my room, perhaps it is making it sound better. I won't know until I get to the listening tests.

It should also be noted that the MCACC has six different memory locations so that you can save different settings. If you want to calibrate the system for a different seat based on activity (if you watch movies from the couch and play video games from the recliner for example) you can do that. You can also have the MCACC calibrate for three different seats at once. In our opinion, it will typically be better to utilize this feature and capture more than one location of data, since you may have a particular issue at the listening position that doesn't exist at other seats. The result may be an extreme compensation that would otherwise negatively affect the remaining seats in the theater,

You can also adjust and/or re-measure a number of different aspects including the channel level, speaker distance, standing wave, and reverb time. The one thing that I found had the most bearing on the sound difference I was noticing was the standing wave. If I switched that off, it would almost sound identical to the un-EQed sound. This makes sense as the standing wave setting seeks to filter out overly resonant sounds (it is essentially a 3-band parametric EQ):

Table 3: Results of the Standing Wave adjustment

Apparently, the Pioneer thinks I have a problem between 150 and 250Hz. This easily explains why I was hearing so much more lower midrange from the unEQed setting.