Axiom Home Page Forums General Discussion Advice from Axiom Owners Auto-calibration Issues

I experienced some trouble recently when I decided to re-run my audio auto-calibration on my 4 month-old home theatre system. I'm hoping that you can give me some potential root causes that I can pursue.

When I ran the auto-cal 4 months ago, the Denon set my volumes within a few dB of zero. With the exception of my sub, it also figured out the distances of my 7 speakers.

This time around, it detected phase errors and set all my speakers to +12dB. I ran the cal three times. The first two times it discovered a side surround phase error. The third time it discovered a rear surround phase error.

At no time did I change the wiring in the last 4 months. I decided however to check the wiring at my receiver and each of the speakers. I found no errors. I also ran in and out of phase pink noise and that checked out too.

I haven't changed anything in my room with the exception of adding a couple of pictures on the walls (yes, it's still the same bare room I had 4 months ago ).

So what is going on?

I'm also puzzled about something else. I sit about 12 feet away from the side and rear QS8s. The sound that reaches my ears is, I would imagine, mostly indirect. So how does my Denon figure that I am 12 feet away? Acoustically, I should be a lot further away than that if the majority of the sound is indirect, right? JohnK and others claim a remarkable improvement in soundstage when they switch from stereo to PLIIx but I can't get the same effect. Maybe that's because there isn't enough delay built in to the surrounds. Maybe I should try setting my surrounds to 24 feet.

What does everyone think of this? I've included pictures below for reference. And my room was recently blessed with holy water so I don't want to hear any demon tales .

Have you resetted the micro processor to factory default before each calibration run? Not sure that would matter, but you might give it a try...

Mo, the first question obviously is whether the holy water was Catholic, Orthodox or what. I've pondered this a few minutes and don't have a technologically oriented suggestion because I've never heard of such significant changes occurring. Incidentally,"remarkable improvement in soundstage" isn't really how I would describe it. There's a relatively subtle overall expansion of ambience throughout the room, the effect of which becomes really noticeable when the surround mode is suddenly switched off and the soundstage collapses to the front.

After about two months my Denon 2807 also started doing strange things. It started setting my VP150 to -3dB to -7dB and my M80s to +1 to +4dB. It also started setting the speaker sized randomly. And the Auto EQ started setting everything from 100Hz to 350Hz to -7dB or more for the center and -2 to -5dB for everything else.

Randy, thanks for the reset suggestion I haven’t tried that.

The reset suggestion is a good one.

Based on what grunt said and what I am witnessing, I am now wondering if properties within the speakers are changing. I can tell you that with my old speaker system, which was good and worn in, the auto-cal was always consistent in setting my levels and distances.

Now with regard to surround performance, look at my room and trace out rays for the sound propagation. The rears have their inside tweeters pointed right at my sweet spot (located by the post). Their acoustic distance is the same as their physical distance. But the sides are a completely different story. The sound from their "front" tweeters has to bounce off the front wall before it reaches my ears. Their acoustic distance is about twice their physical distance.

So I changed the settings in the Denon as per above. And you know what? Instant ambience!!! Now I know exactly what JohnK and others are talking about when they say that PLIIx adds life. I still need to tweak the speaker volumes but I think I have discovered the answer to the long-standing mystery of PLIIx.

But I still don't understand why the Denon is getting confused with the phase. I wonder if it's getting confused with that post but the post was there 4 months ago too. I'll have to try Randy's reset suggestion.

So now I am curious. How are you all setting your delays (distances)? Are you letting your receivers do it for you or are you "ray tracing"?

I too had similar issues with my Denon on it's auto db setup. It would come up with totally wonky numbers. I have never run the auto EQ to see if it was also messed up. A full processor reset made the problem go away and it has never been a problem since.

Hardest part is remembering where you stored the manual to get the reset sequence. I'd post it for you if I could remember either. Denon has copies on it's web page though.

I'm pretty sure I read somewhere that my Denon 3805 could occasionally warn of phase errors when there actually were none.

FWIW...

I agree that it must be the Dennon out of whack, the speakers wouldn't change to this degree.