Axiom Home Page Forums General Discussion Home Theater VP150 in a hole?

I was calibrating my new Axiom's using the AVIA disk. I have M60's for fronts, VP150 for a center and M22's as rear surrounds. These speakers are being run from a older Sony STR-DB940 A/V receiver. When I run the test which compares the left front with the center, it sounds as if the center is accentuating more of the upper bass than the left M60. It sounds rather like the VP150 is in a hole or something...not horrible but definitely noticeable. I was under the impression that the timbre of these speakers would be very similar especially in the higher frequencies...I have run a Real Time Analysis program on a laptop using the above tones supplied on the AVIA disk, using a cheap Sound Blaster mic and recorded the tones reproduced by the speakers. There is a noted difference in the frequency response graph between the left and the center...peaks in the upper bass from 60 to around 500 Hz or more occur in the center.

I thought it may be affected by my having the 150 on the shelf under my Sony KV36XBR800 TV. The Sanus Video stand on which the TV sits has a front center post adding support to the center of the top shelf holding the set (which weighs in at approx. 235 lbs) and therefore the speaker is two or three inches back from the front of the shelf. As an experiment, I put the 150 on top of the set and ran the AVIA test again...I noticed that the comparison between the two speakers (left and center) still has that difference of the center sounding like it is in a hole.

I performed another experiment this morning. I switched the speaker connections on the receiver between the center and the right front (making the left front and right front speakers identical...both M60's). I then ran the tone set again from AVIA comparing left front and center and the right front exhibited the same issue as the center does when the center is connected to the center's speaker connections.

Also, the standard individual level tones used to set all five speakers level also exhibits the "in a hole" effect for which ever speaker is connected to the center output...using this test, upon switching the connections (VP150 connected to the right front output), the center sounded more like it was supposed to (at least what I was expecting...more treble response) than when connected to its correct set of center speaker posts. Has anyone heard of any situations where the output to the center channel on a specific receiver was tonally different from the other speakers? Could this possibly be an issue with the signal on the AVIA disk for that specific test or an issue with the center output on the receiver?

This is something that I "can" hear...I tried recording it with the mic I had available just to see if it heard (and recorded) what I was hearing and that my mind was not "making it up...". I have no other "effects' turned on...no DSP of any kind except for the standard Dolby Digital decoding of the AVIA disk...

Anyone...anyone?

WhatFurrer

my guess is the center channel on your receiver.

i had a receiver a couple of years ago that had a defective center channel.

I second you WhatFurrer! I bought the VP150. It was my first speaker. So what was I to know. Now I have a pair of M2s (M60s on the way - factory seconds wait list). And the M2s and my center channel have a different tone between them. Thats both with the Avia disk (which I have) and using the test tone on my H/K 630. It's hard to believe no one else has this problem. Do we have something wrong with our speakers? Mine is on top of my 53" Sony, angled down. But man...I can't imagine moving it up or down would change the OBVIOUS tonal difference between ALL my speakers (surrounds included)to my VP150. What to do?

There was a thread a while back started by me that brought up the same issue. You can view it here:

http://www.axiomaudio.com/boards/showthreaded.php?Cat=&Board=HT&Number=30827&page=&view=&sb=&o=

Basically, we're wrong and the VP150 is a perfect timbre match to all the Axiom speakers. There's nothing wrong with your VP150. It's the best!! BTW, I sent mine back.

You sent yours back? As in...an accident back? Or, after you learned everything still sent it back? Thanks for the link by the way. I'm off to read it!

After I learned everything, I sent it back.

So what are you using now?

Hi Whatfurrer

Is the STRDB940 a 6.1 receiver? I know the 1070 has 2 center channel speaker outputs - one for the front center and the other for the rear center. I know it's a dumb question, but are you sure you are using the correct center channel output?

2x6spds,

The DB940 is a 5.1 receiver (circa 2000) so the center is the only center available. Wish it were 6.1 or 7.1 but I did not know then what I know now...

Regards,

WhatFurrer

NHT M5, IMHO a properly designed 3-way center that matches very well my fronts (also M5s).