Rear Wave

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I am sitting in my room, playing my guitar. Sound radiates from the back and the front of the guitar, and to some small extent from the sides. It behaves, therefore, a bit like a dipole, or an omni. If I replay a recording of it, surely I want the transducer to do behave in the same way as the guitar - the omni will probably get closer to how the guitar behaves than the dipole, in all honestly.

So, by the trap argument, don't I need some traps in my room to make my guitar sound better? Of course not - reflections off the walls are part of the deal. Conversely, adding traps can only make the transducer reproduced guitar sound less like the real one.

Good point, but you're missing a key point: a good recording of your guitar will capture the room ambiance to which you refer. The last thing you want is the room in which you listen to the playback of that recording asserting its sonic signature.

In other words, if your room adds its own ambiance to that of the recording, one could argue that your room is having a deletarious effect--an effect that judicious use of acoustic treatments could (help) prevent.

Enough of my rambling!
 
Ok, that makes good sense to me. My room is overly "live" sounding. I think that's why the absorbers work so well. As a matter of fact, now that I've got five absorbers working, I still need to add some more. What I'm finding is what has already been discussed, that the system becomes more enjoyable at elevated volume.

ok what I have done and many may laugh but if your room is too live I turn around so that my mains are behind me if you can here much of the sound coming from in front of you then there is a problem. you can also cup your hands around your ears to help localize the sound you will be surprised how much sound comes of the back wall especially with logans the esl creats a wall of directional sound that will bounce back at you and ruin your stereo imaging!
 
While I am certain the addition of bass traps has markedly improved my room, I am still debating whether or not I like the loss of ambience derived from placing acoustic panels behind my Summits. See my description in this earlier post...

In agreement with Alan on this one.

While I don't have the best setup for 2 channel listening with a big projection TV sitting in between the mains I feel I've been able to obtain what I feel is a pretty good sound.

I have a pretty good size room, I believe it's 22'x23'. The speaker panels are 4' from the front wall and 4' from the side walls.

The GIK Tri-traps in the front corners made a dramatic improvement.

I originally had the GIK 244's behind my mains, but like Alan wasn't totally happy with the sound. I currently have a smaller 2'x2' acoustic panel behind the mains from ATS Acoustics. Which doesn't completly absorb all of the rear wave, and I'm happy with the sound.
 
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ok what I have done and many may laugh but if your room is too live I turn around so that my mains are behind me if you can here much of the sound coming from in front of you then there is a problem. you can also cup your hands around your ears to help localize the sound you will be surprised how much sound comes of the back wall especially with logans the esl creats a wall of directional sound that will bounce back at you and ruin your stereo imaging!

Well I agree some room treatments are necessary to help areas of concern. I am still experimenting with direct sound absorption behind the speakers. I run a big center panel that is taking care of the diffusive stones along the fireplace and some tiny 6 inch corner traps that seem to stop some bass boom !


Yes I have stood dead center of them with my back to them many times and I use this when setting up all ML speakers. I use it exactly what you said. If you have a good set up the image will be right behind you about 5 feet. Drums should be heard back there as with vocals. Turn around and its like GIGANTIC headphones . It sounds quirky and many have asked what I am doing but I can get it to work !
 
do you have a basement underneath you C.A.P? I am above a garage even though I have a thick floor nothing beats wood floor on a slab in my opinion.
sometimes when I am jamming heavy especially classical music the bug drums
will resonate the floor I do not like to hear that :eek:! maybe I am just getting crazy
 
I'm on slab with engineered wood glued directly to cement. The basement is behind me under neath. Its a Quad level. Bass is tight and deep.
 
I have to say, when I moved from a place with carpet on a hollow floor, to wood glued directly to a cement slab, the bass improved dramatically! In fact, despite (or for all I know, because of) a minor echo in my new place, the sound is really much better than I expected.
 
I'm on slab with engineered wood glued directly to cement. The basement is behind me under neath. Its a Quad level. Bass is tight and deep.

YOU LUCKY DUCK !!!!

I know this is a little of the subject but many people buak at the prices we pay for our speakers and systems
but hell its the rooms and the right house thats the expensive part you know.
 
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Yep, same here. 12" concrete slab with some throw rugs on top. Also glued and screwed all of my drywall with R-32 in the walls. Really helped the sound a lot...

Now there's that new "acoustic" wallboard...

Hmmmmmm
 
don't be silly

Hmmmmmm, last time I worked on a concert hall, the engineers specified 8" reinf. slabs, and that was considered overkill! 4" thk. conc. over wire mesh and gravel base is more than adequate for a listening room. If it moves, get out! You're having an earthquake!
 
The ambiance provided by the rear wave may beneficial in the right room, where you can get the speakers out five feet or more from the front wall and other factors are such that the wave doesn't interfere too much with the front wave. But for most listening rooms, I think rear wave dampening is essential. Like anything else in this hobby, it is a user-preference. But I think JonFo did a great job in his thread on acoustic treatments showing the reduction in harmful reflections by dampening the rear wave.
 
Like FISH MAN, my listening room is also above a garage separated by standard 24" trusses. The bass from the Depth i was coming up from the floor so I lifted the Depth i off the floor with an 18" square ASC Sub Trap. That helped a great deal. Now the bass hits me in the gut, not in the toes.

I also put up nine various Real Traps around my combo living room / listening room, Thanks Ethan, to compensate for the unavoidable asymmetrical layout. With each addition I noticed an overall improvement in balance and transparency.

For the last few weeks I've been battling a bad sinus infection that has really screwed up my hearing. I have a stack of new albums that I can't enjoy until get through this.

Just wanted to jump in and say Hi. I read this site everyday.

Satch
 
don't I need some traps in my room to make my guitar sound better? Of course not - reflections off the walls are part of the deal.

Have you recorded your guitar in this room? Most small rooms sound small and boxy when you record in them unless you put the microphone very close. But when very close, the microphone doesn't pick up a balanced sound. Absorber panels reduce the "early" reflections which cause that small boxy sound. Then you can put the microphone farther away to capture a better tone, and you won't get that off-mike sound you get in an untreated room.

Related to this, just a few days I completed a video experiment that attempts to capture the true sound of an instrument in the room using a microphone. Look for Recorded Realism near the bottom of the RealTraps Videos page.

--Ethan
 
User211,

I have my guitars and basses set up in the same room with my stereo and love the way the room sounds with the acoustic sound traps. It's kind of like when you play a live gig in a small venue and it starts to fill up with people. I've had some good sessions here with some talented players and they like the way their guitars and amps sound also. All I'm saying is that it works for me...

Satch
 
Ethan, just watched the video. Maybe I'm a bit tired because I am a bit confused after watching it. I thought I heard really substantial differences between the live playing and the reproduced, just through the laptop speakers. My DAC is down so I can't check it out through the Logans. Will check it out again tomoz, along with some of the other vids and your welsite as a whole...
 
Hello Ethan

I have been spending a fair amount of time on the AVS Home Theater construction forum. Logans and other dipolar speakers are usually not recommended for home theater applications. Whats your thoughts on this? Can room treatments help with the short comings in this enviroment?

Thanks
Lance
 
Hello Ethan

I have been spending a fair amount of time on the AVS Home Theater construction forum. Logans and other dipolar speakers are usually not recommended for home theater applications. Whats your thoughts on this? Can room treatments help with the short comings in this enviroment?

Thanks
Lance

1) in most home theater's the speakers are only 1 part of the whole setup and most are not willing to hand over 5-9k+ for just the mains and that's what you have to do if you want home theater performance out of a electrostatic speaker you need power for great sound presentation!
3)HT setup websites are rated on there performance per buck ratio and logans do not fit into this criteria plus they have maintenance issues that most weekend HT warriors will not deal with or understand
2)store like barrets have harped on the weaknesses of electrostatics for years just because they do not sell them which only makes them look like the salesman that they are(maintenance and setup guys too) this has scared of many new enthusiast who are usually into HT first.
3) I have a HT and it sounds great yeah the guy on the right may loose a little form the left but who cares I sit in the middle! the resolution electrostatics offer far out ways any negatives of placing them in confined quarters.I do not think I could go back to a conventional speaker after owning these other stuff just sounds like its being played threw a wet paper bags and it hurts my ears!
that's just my opinion and you know what the say about opinions !
 
I thought I heard really substantial differences between the live playing and the reproduced

As I explained in the accompanying text and last portion of the video itself, I didn't feel we were entirely successful with this experiment. But some of the instruments were pretty close IMO. Perhaps you've never tried recording, but usually the disparity between what is heard in the room versus what is captured from five feet away by a microphone is much larger.

--Ethan
 
Logans and other dipolar speakers are usually not recommended for home theater applications.

Fish already gave you some good answers on that.

Can room treatments help with the short comings in this enviroment?

Room treatment always helps regardless of the speakers and gear, or how the room sounds initially.

--Ethan
 
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