Minimizing room effects

[jasonb]

I recenctly had the chance to borrow a pair of Sennheise HD-650 headphones for a week, this is the first time I have listened to a "high-end" pair of headphones. The thing that impressed me the most was how much easier it was to resolve detail without the effect of the listening room coming in to play as it does with speakers. This leaves me wanting to experiment with speaker designs that are more directional to minimize reflections from the surrounding walls. I see a few possibilities and would like to hear some more suggestions as well. I realize room treatments would be easier and I may try some as well but for now I want to concentrate on speaker ideas.

1. Waveguide tweeters - waveguides decrease the dispersion of tweeters and eliminate cabinet diffractions and minimize room reflections

2. Foam blocks around the tweeter, similar effects as #1 but without the added bonus of increasing the output of the tweeters lower range

3. Dipole speakers - the radiation pattern has nulls at the sides, top and bottom, minimizing reflections off the walls, floor, and ceiling.

Any other options?

Thanks,

Jason

[natediggidy]

Provided Link: Underneath the cover


RIGHT THERE, you said it.

Unless you have an optimal room, the sound comming out of those speakers is going to go somewhere and get affected by the room as soom as it hits a boundary.

Many a good speaker has had it's sound messed with by the room's interaction.

If you have conventional box speakers, absorber panels on the side walls's first reflection point will greatly improve things. You don't have to go overboard to get the benifit either. Mine are simply DIY 2'x4' panels, centered at seated ear level.

You can DIY some absorber panels in an afternoon. Far quicker than you can build a pair of speakers. Once the room is properly treated, any speaker there WILL sound better.

I realize this forum is geared to speaker building but, unless you're playing your speakers outdoors, that room will com into play.

[damkor]

...is to sit closer to the speakers, and equalize their sound for that close listening position. In general, they sound a bit brighter up close... and more like headphones obviously.

[cole]

Catching those first reflection points is key to releasing the detail in your source material. The best upgrade you can get your system is some room treatments! You will be amazed at the difference in sound detail and they dont even have a plug. And yes, they are way easier to build than your average set of speaks. My whole room has 8 mid/hi absorbers on the side walls, bass traps in the corners and where the wall meet the ceiling.
All done for under $500.
I got plenty of info and some pics of construction if you decide to make a worth while jump.

[wingnut]

<A HREF="http://www.madisound.com/catalog/pro...oducts_id=1615">http://www.madisound.com/catalog/pro...oducts_id=1615</A>

I chose this driver for a 5.1 IB setup for the very reason you are thinking: I wanted to try to eliminate interaction with the IB, and to a lesser extent, sidewall and ceiling/floor boundaries by using a horn-loaded/waveguide type tweeter. Price, performance, ease of installation, and a much simpler x-over also came into play.

THX had an interesting and controversial spec. for their certified speaks about 10 years ago that required a very highly focused dispersion pattern. I've never seen a DIY version, but to be certified most manufacturers incorporated a modified D'Appolito -- MTTM -- design that produced this effect. Manufacturers like Klipsh were able to accomplish this feat with their signature horn-loaded tweets.

Interesting topic.

TTS

[zachc]

I built a pair of the panel absorbers from John Risch's site. I have to say, I was surprised how much difference these made when placed behind the speakers about 6 inches off the rear wall. Unfortunately, My room doesn't lend itself to side wall treatments.

Been thinking about some diffusers for the back wall though.

Zach

[wingnut]

Cole,

Very well done! You're room treatments look great! Actually, one of the few *budget* treatments that I've seen with some real aesthetic appeal (of course those systems that the pro-jocks and hollywood celebs install always look great, but that ain't DIY!).

I'm interested in seeing some pics as I'm in the throes of finishing a basement and installing a HT.

Thanks,

TTS

[paul_n_oneal]

Nice job Cole! And it blends in with the walls making it look like it's part of the room. I like your colour combination too. Excellent job and I will try and keep this in mind for my next listening room.

Paul