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Posted By: Nachosgrande Where are your VP 180's? - 12/14/16 05:42 PM
I just swapped in a VP 180 from the 150, and the one thing I noticed right away was the reflections off the back wall/ceiling, as the unit is mounted above my 60 inch TV. It doesn't have as much breathing room to the back wall, as there is only a few inches space now due to the 17 inch length. I am going to add some absorption pads on the wall to deal with this.

As most of you are using this VP180 with a mounted OLED/LCD TV or on a stand/unit with minimal space to the nearest wall behind the TV, what have you done to eliminate this issue?
Posted By: bridgman Re: Where are your VP 180's? - 12/14/16 06:01 PM
I'm not exactly your target demographic because I'm using a (720p) projector & wall-mounted screen rather than TV and stand, but I have M60s and VP180s pulled well out from the wall. Roughly 15" between back of VP180 and wall.

Never thought about the "close to the wall" problem but it is a good point. That said, there should only be pretty low frequencies coming out of the ports so wondering if some kind of "jet deflector" arrangement angling down behind the VP180 would help ?

At first glance that seems like a stupid idea because the wavelengths involved would be so much longer than the deflector but it seems like it should at least help to stop the "puffs of pressure" coming out of the ports from being reflected back into the ports immediately.
Posted By: nickbuol Re: Where are your VP 180's? - 12/14/16 06:08 PM
Yeah, my VP180 is directly behind my acoustically transparent screen in my projector setup. I also have my front wall completely treated with acoustical treatments for absorption that would suck up any stray reflections from the backs of my front speakers.

I also have my VP180 about 18" between the back of the VP180 to the front of the treatments on my wall.

So I don't fit your model either, but I just wanted to reply.
Posted By: bridgman Re: Where are your VP 180's? - 12/14/16 07:15 PM
Originally Posted By Nachosgrande
As most of you are using this VP180 with a mounted OLED/LCD TV or on a stand/unit with minimal space to the nearest wall behind the TV...

Based on our current sample space of 2 this may turn out to be a questionable assumption smile
Posted By: MMM Re: Where are your VP 180's? - 12/14/16 07:31 PM
i put mine below the 65" TV on an ikea besta stand. I have about 8" of space behind my speaker and it works fine for me. But then again i don't know how well my hearing is to know what the reflections you are talking about.

try moving it down below the tv and pulling it out. stick it onto a box or stool so that the front edge of what it is sitting on doesn't interfear with the front of the speaker. Then try moving it out into the room till you get it to sound right. if it's too far out, you could try putting a sound absorbing material behind it like Roxol Safe'n'Sound.
Posted By: bridgman Re: Where are your VP 180's? - 12/14/16 07:44 PM
Do we want to absorb the energy coming from the ports ? My understanding was that it made up an important part of the overall output from the speaker.

I was about to say "I imagine most of the port output will be below 80 Hz so maybe not a big issue for HT" but then remembered that VP180 is probably one of the "most likely to be set to Large in the AVR" speakers out there.
Posted By: nickbuol Re: Where are your VP 180's? - 12/14/16 07:57 PM
Originally Posted By bridgman
Do we want to absorb the energy coming from the ports ? My understanding was that it made up an important part of the overall output from the speaker.

I was about to say "I imagine most of the port output will be below 80 Hz so maybe not a big issue for HT" but then remembered that VP180 is probably one of the "most likely to be set to Large in the AVR" speakers out there.


I would answer this as "it depends." I have my wall treated, and it is great, however it isn't this massive energy trap either. In fact, outside of my front bass traps, I have probably more "effective" absorption in 2 of my wall panels in the room than the entire front wall due to the difference in materials used. My front wall is much less absorptive than it may come across. Just enough to make it not a massive reflection point causing a delay between the energy coming from the front of the speaker and the reflection off of that wall. In my situation, I am not absorbing much of the deeper frequencies which have longer wavelengths and aren't as noticeable when dealing with that front wall reflection.

So for me, it is less absorption of that ported energy.

I would think that if he is getting noticeable reflections off of the ceiling/front wall, then even some thin 1" OC703 or similar would help. I am not a huge fan of 1" acoustical insulation as it doesn't work well for the sound as a whole, but it will get those most noticeable highs sorted out.
Posted By: TroyD Re: Where are your VP 180's? - 12/15/16 04:59 AM
I had my vp180 about 12" from the back wall.

I built a stand from 1x2 wood. Made it so it had no bottom.
basically it sat on the legs. I put a shelf about 12 " below and about 6" off the floor. Stand was 18" off the floor in rear and 19.5" in front so it was angled towards my listening position. worked well with no bottom reflections. wall behind was treated with 2" of sound board and a 1" gap between the insulation and 3/4" off the back wall.
Posted By: Nachosgrande Re: Where are your VP 180's? - 12/15/16 04:08 PM
Thanks for the thoughts....I'm a bit constrained right now to above the TV until I get a new setup down the road. I guess I'm getting a "boxy" sound out of it, very localized, perhaps I need to adjust the angling, but I'm wondering if the wall,ceiling reflections are the issue, I have some foam acoustic panels coming, will try to mount them above and behind the VP180's
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