Axiom Home Page Forums General Discussion Home Theater VP150 - dialogue sometimes sounds harsh

i have a vp150 as my centre channel speaker. it's served me well, but recently i altered my set up with a new tv stand and receiver and every now and then i notice that dialogue will sound harsh or shrill on certain notes. it's hard to explain exactly what it is, almost like it's too bright, or there is some sort of vibration.

about my current set up - yamaha rx-a800 (although i've also tried a yamaha rx-v667 and pioneer vsx1021k with similar results) with m60s and qs8s.

i have the bass crossover set at 80hz, and have tried adjusting the level downwards for the centre speaker - and that helps if i lower it enough, but then i miss some of the dialogue.

it's an original vp150. what are the differences between the v.2 and v.3? i should note that the little stick on rubber feet are long gone. i thought perhaps it was vibration causing the harshness so i stuck a couple of dvd cases with foam around them to raise the speaker, but that didn't really help. are those little rubber feet so important?

any ideas?

Have you ran Yamaha's YPAO sound correction program in the receiver?

yes

Have you tried it without YPAO?

We don't really have a lot of details on the v.2/v.3 differences, but of course the v.3s are said to be smoother with better dispersion, etc.

I don't think the rubber feet are crucial.

Is the VP150 right up to the edge of whatever it's sitting on, or is it back on a shelf? That could be changing the characteristics of the sound.

Or maybe you just need a VP180.

yes, i've tried it without the YPAO as well.

i've tried the vp150 in the middle of the stand, closer forward and farther back. still happens.

it's not like it's a constant problem, but when it does it's really bothersome. i don't recall hearing it before i changed my set up, so i think it has to be the crossover setting, or some reverberation from the stand.

the small rubber bumpers can be purchased at any building supply and will help to de-couple the speaker from the shelf. Always have the speaker slightly forward of the shelf edge so not to obstruct the dispersion. Ideally your channel level should be set to 0db/+1 db, you may need to lower the output of the other speakers to achieve the best results. Also, try a different crossover for your center, try 90Hz or 100Hz, listen if this makes a difference.

I'm thinking changing the crossover probably won't really help with the higher frequencies and harshness you describe, as that would not be around the lower frequency ranges.

Possibly check your speaker wires to make sure you have + to + and - to -. As the others have stated, you want it up close to or beyond the shelf lip so you don't get any unwanted reflections. What surround mode are you listening in, I assume one of the dolby or dts modes, and not one of the special modes. Now that it is on a shelf, do you have it angled upward by flipping the speaker over? Have you tried listening close to see if possibly one of the drivers is bad...

just a few thoughts.

Seems to me this is the most likely culprit. I know the sound of my VP150 changes a lot when I move it around in my TV stand. Just try moving it around best you can.

Have you try turn the VP150 the other way round i.e. angle up or down?

I did it and it does bring better result but to me the VP150 still the weakest link in my Axiom setup...am considering the VP180 as the VP160 is too tall and will cover a little of my screen.

if anyone with a vp150 has the fellowship of the ring extended edition bluray, please pop it in and have a listen at around the 2:00 min mark. there is some dialogue ..."and into this ring..." that hits the notes that give off the buzz. play it loud and see if you hear it.

i don't think it's vibrations from the stand as i placed a pillow below the speaker and i still hear the noise (i'll call it a buzz, but i'm not sure that does it justice... but i do think it's some sort of vibration) I also flipped the speaker (which is actually how i had it before) and while there might have been a minimal improvement (probably because it was now pointed slightly up instead of directly at me) the noise was still there.

the more i look into this i think it's a matter of internal resonance in the speaker. could this have developed over time? perhaps the cabinet loosening up? (although the speaker has rarely been moved). perhaps if i removed a driver and stuffed some extra insulation in the interior? would the fact that there is no port on the vp150 lead to some internal resonance?

i'd love to upgrade to a vp160, but that simply won't be happening in the near future (just upgraded my receiver and have to replace my sub first)

Sometimes it can be hard to hear if a particular driver is having a problem just by putting your ear up to it so I suggest the following.

If you haven’t already, rule out that it’s a loose dust cap on one of the midrange drivers. I had this problem with a new M22 and it only happened on certain frequencies. Play a scene with the offending buzz and hold your finger on the dust cap of each driver in turn and see if it eliminates of at least muffles the buzz. This would be my first guess since it seems to be an older speaker.

You could also check the mounting screws on the drivers to make sure one of them hasn’t come loose.

If that amounts to nothing it could still be something else wrong with a driver like Randy suggests. So one at a time I would remove each driver and disconnect the wires starting with the midranges, since it seem to be a lower frequency from what you’ve said. If the problem goes away when you disconnect a particular driver then reinstall that driver in another position and see if the problem follows the driver. If not put another driver in the offending position and see if that driver has a problem. If the problem is with what position the driver is in regardless of which driver is there then look for something near that driver that could be vibrating including a loose wire on the crossover.

If there is nothing at all wrong with the drivers or the position then it could be a bad crossover. I had that problem with a new M2 when only a certain frequency was played but luckily those come in pairs so after eliminating all other possibilities I swapped the crossovers and the problem followed the crossover.

thanks for the suggestions. i'll see if i can identify if it's a bad driver.

Well i don't think it's a dust cap, and i cant isolate it to any specific driver (it seems to be internal, like a vibration from the cabinet.

I guess i'll disconnect the drivers this weekend when i have some time and have a look.

also wondering if anyone with a vp150 had a chance to listen to that passage from fellowship of the ring?

Know the passage well but no longer have a VP150; I don't recall any issues when I had my VP150. It could possibly be that the crossover in the VP150 is having some trouble and no longer functioning as it should.

Well i took a look at the drivers, they all seem to be connected well and in good working order.

I connected an Energy bookshelf speaker as the center channel, and the same problem is replicated, so my felling is that buzzing note is actually on the source recording. I think the VP150 is a better speaker and just exposes the flaw in the recording more (and now with my new set up where the centre channel is more optimally placed i here the flaw more).

I'm glad you figured out the problem!

yep, I don't know how many times I've told people over at AVS that Axiom speakers aren't bright, but true to the recording.

I'm glad you were able to duplicate the problem so you know it isn't the VP150, nothing like reassurance.