Tuning speaker / room response?

like garfish, i'm really impressed with the fact that your post is like none i've ever seen. will you kindly share with us how you imported the graph?

The graph is actually pretty simple to do. You put it on a web server, then include a link in your post. The link is done by a simple html tag.

Using square brackets in stead of smaller than / greater than signs, the tag looks like this: [img src="http://www.myhome.org/pics/roomresp.gif"]. You would of course use greater than in stead of [ and less than in stead of ].

Niels.

You need to take into account that the RS meter is not REAL accurate in the first place. There is a list of corrections that need to be factored in before you start "gutting" your room, buying room treatments, moving your speakers, etc... I can't seem to find the website that posted this info nor the sheet that i printed out with the specific corrections. Once i can locate either one of them, i will post it here unless someone beats me to it. Sean
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I'm also impressed with the graph. I don't have a web server at my disposal--so I doubt I'll try this at home. As to the problem. A couple of things, the meter should be on slow response. I've done it both ways, it doesn't seem to make much of a difference so I believe your graph is close to accurate, with the exceptions of Sean's post (which I'm very interested in the website). Mikec's post points out some very good areas for info. However, I'll bet you have a little over an 11 foot span between walls, or that's your ceiling height (or close 10.5 feet). Room tuning works very well about 125Hz. It does work at lower frequencies, but not nearly as effective. That bump at 50 Hz will be difficult to correct without electical correction. Most people, including myself, consider equalizers a measure of last resort--but if there is no other way--it will make a big improvement. Infinity has a single notch filter on their new speakers to accomplish exactly this. Tact has been making digital correction systems for sometime. Perpetual technologies also has a digital domain correction engine (but this only works if you ONLY listen to digital sources throught the Perpetual technologies P-1A). It seems to me there is a market for a very low noise low frequency addustable notch filter. This is such a common problem. McIntosh made room correction equalizers. They are very good--but something simplier with less noise would be prefered. Looks like an opportunity for someone or some company.

To really understand your graph you should describe the dimensions of your room, the position of the speakers and the position of your measuring SPM. If the graph is the speaker response at your normal listening position, then your have a fairly flat system response. IT IS NORMAL TO HAVE IN ROOM RESPONSE MEASUREMENTS SIMILAR TO YOUR GRAPH. The dip at 200Hz is probably a floor reflection phase problem. Try experimenting with speaker toe-in to address the peak at 4KHz. As a reference, perform the same measurement 1 meter directly in front each speaker. They should measure much flatter.