Axiom Home Page Forums General Discussion Home Theater denon 3805/Polarity warning

I've recently set up my new h/t system and love the Axioms!!I made a great choice. I am having one issue with my setup that concerns me. The first time I ran the auto setup program on the 3805 to calibrate my speakers, one of my surrounds (qs8's)sounded bad. At the end of the set up procedure the Denon screen said I had a Polarity problem with that speaker. I checked the wires to that speaker and it appeared that the installer did switch the red and black wires. I changed them around and ran the set up again. It sounded much better and I didn't get a polarity warning. Great right? We'll for the heck of it I ran the auto set up again last night out of curiosity. The speakers all sounded fine but the polarity warning came up again for that one surround speaker...Any idea whats goin on? I'm not ruining a speaker here am I? Thanks guys for your help. Axiom rocks my house!

I've heard that the polarity warning is often wrong on those auto-set up recievers. It should be fine.

Hi divot:
I've run the auto setup quite a few times and have never received that warning. Maybe you have a stray speaker wire somewhere in the connection or a loose connection.

You can also try one of the THX setup guides on dvds paying particular attention to the phase test.

Good luck and let us know how it turns out.

I agree, the polarity setup is very accurate. You might want to double check your work to make sure you don't have a stray wire touching the opposite terminal, that is all it takes...

good luck

I'd think that would be more likely to cause the thing to shut down in protection mode than report an incorrect polarity!

True,

In reading my manual on the 2805, step two of the Autosetup checks for polarity, I guess I just figured it might be able to detect a stray wire or two, your probably right Ken.

I have found the polarity warning not to be accurate at all on my 2805.
I've run the auto sequence many times and have gotten different readings several times with nothing changing.
In my opinion I think your better off using the a test disc to determine some things.
However I find the auto distance and db settings to be right on.

I've found my 3805 is wrong one in five times.... without any rewiring being done in between attempts!

yeah, i've gotten the warning a couple of times when doing the auto setup, and i KNOW for a fact the polarity is correct. i vaguely remember seeing a note about this occuring with the QS-type speakers in either the Denon manual or the manual that came with the speaker...but i can't seem to find it looking at it now.

This sounds like a problem that should be voiced to Denon for a fix in their hardware.

I can imagine their reply :

Dear Sir :

Thank you for your recent feedback concerning the auto-polarity capability of your fine Denon receiver. Please understand that IF YOUR SPEAKERS DID NOT HAVE DRIVERS POINTING IN ALL DIRECTIONS the auto polarity system would have no problem operating in the reliable manner you have come to expect from Denon products.

If I might suggest a test, perhaps you could repeat the auto-polarity check with some speakers WHERE THE SOUND COMES OUT THE FRONT LIKE GOD INTENDED. Using those speakers I believe you would quickly find yourself to be very satisfied with the fine engineering included in every Denon receiver.

I hope this helps. Please do not hesitate to contact us again if we can provide further assistance.

Yours very truly,
Customer Support

^^^
Good point...I didn't think about the fact that the Q's have speakers pointing in multiple directions. Makes sense. But do all the other folks that say they have this issue, have multi-directional drivers also?

The only speakers that my Denon reported as having wrong polarity was my QS-8s.

I never thought about the multi-drivers causing the erroneous reading either.... makes sense!

If I had to make another guess, I would guess that QS8s on the back wall have few problems with auto-polarity while QS8s on the side walls drive the auto-polarity logic batty...

I never thought about the multi-directional qualities of the qs8 throwing the auto setup for a loop, but it does make sense. It might be worth a try to reposition the speakers, then rerun the setup.

I have my speakers located on the side and sligthly behind the listening area and toed in a bit. The only problem I've experienced when using the denon mic is it boosts the db level a bit more on the 8s.

My bet on that actually is their quad-polar nature. I imagine di- or bi- polar speakers would have the same issue. I don't remember which is which at the moment, but one has drivers wired out of phase with the others.

I have a Denon 3805 and have had the same problem a few times...I spoke to Denon and they say that this is possible with dipole type speakers (or qudrapole in your case) and that there is nothing wrong with the receiver. I have polk dipoles...the diffuse sound confuses the mic...Denon said to try to move the mic foward (or back) a bit to try to alleviate the problem. You would think Denon would have thought of this and factored it into the setup...make next years model will do a better job. Otherwise this receiver is awesome!!

yeah, with the $65 bucks you spend on the mic that doesn't work too well with the QS's you could go out and buy an Avia disc and a SPL meter and get better results. i guess denon figures a relatively few number of people have di/quad pole speakers so it's not worth the effort to accomodate them in the setup. speaking of which why the h-e-double hockey sticks do we have to shell out extra dough for a mic when the 2805 buyers get it for free?!? whiskey tango foxtrot?

In fairness to Denon, the whole idea behind the quadpole speakers is to smear the sound around so it sounds like a bunch of different speakers at different locations.

If Axiom is doing their job right then Denon will not be able to do theirs (polarity determination based on simply listening to the returning sound). If Denon was able to make auto-polarity work all the time it would be pretty clear that Ian needed to go back to the drawing board

Thanks guys, I appreciate everyones feedback...I'm sure it's the design of the speaker that throws off the Denon. By the way, what do speakers sound like if the polarity is reversed? Instead of english, do the words come out in german? Ha Ha. Or maybe every phrase ends in "Ehhh"...no I am serious, anyone know?

It's probably hard to tell with surrounds because they only get bits and pieces of the content anyways, but here's what you see with the mains :

- when polarity is correct (left and right are the same) your brain sees the sounds distributed properly between the speakers, with many sounds clearly coming from the midpoint between the speakers

- when polarity is reversed you hear a weird "phasey" kind of sound (you know the sound a phase shifter (not a flanger) makes on a voice or instrument ?) and the sounds seem to move more to the outside, ie there is sound on the left and on the right but nothing in the middle

If you're not a musical instrument junkie and aren't familiar with phase shifters let me know what you do watch/listen to and I'll try to give you an example