Axiom Home Page Forums General Discussion Advice from Axiom Owners I Graphed...Now What?

Alright, after all the build up, the new Behringer UControl, the testing, the wires, the confusion...I now have a graph. But now what?

So, here I am, seeking "Advice from Axiom Owners." Based on this graph, what do you, the Axiom Nation, recommend for the highest bang for the buck to fix my graph. Now, after reading the REW forums, I find there are far too many opinions and far too few facts to chase all the rabbit trails. For example, this well done article seems to bust a big hole in the chase for a flat graph. The right curve. So, I trust you Axiomites to tell me what sounds best, not what looks best?

Now, stop laughing at my seismograph chart and help!

Me?
I'd start drinkin'....


Can you post it a bit bigger to see it?

Dude,
I know that graph. It's the S&P 500 over the last week, it's not an audoio graph! What are you trying to pull?





PS. You have a graph, I'm jealous...

I guess that was a bit small, but it makes the peaks and valleys look smaller, so it sounds better.



Edit: never mind, I refuse to fight Axiom's image issues again. It is on my photobook page if anyone is really interested to help.
Bigger Graph

Edit 2: now it fixes it! Apparently you just have to beg it.

Worked fine for me.

By the way, I read that the Radio Shack digital SPL meter is not useful over 300hz so I'm ignoring that region of the graph. Helps me sleep at night.

Did the software add the comments to the graph? If so, very useful that it 'interprets' the data for you.

Something like that.

300Hz is awful low for the thing not to be effective. You might not want to sleep that well at night...

I'm just filling time until someone who can say something useful comes on.

are your mains angled inward or straight out? I found by adjusting my 80's further away from the side and front wall, and playing with toe-in, it helped that dip, as did the bass traps.

I'm heavily toed in right now to nail the image dead center. My room is small, 1700 cubes I think, in case that matters.

It's nothing a set of M80s can't fix

With the downloaded calibration settings, the RS meter is good to about 3000hz.

Mojo was heavily toed in as well and found he liked his M80s even more with just a little toe-in.

Thanks, that's just what i was hoping for.
[runs off telling the wife to fire up the car, "got to get a new microphone!"]

I had read that the RS meter was good to around 2000Hz so that agrees with what Jay wrote.

That dip at 70Hz is common in our rooms and often relates to a room height mode. Corner bass traps may help and you can also try traps above the listening position (didn't make any difference for me though).

Both corner traps and thinner (2") traps at first reflection points should help with the dip at 300Hz. Changing speaker position can also help here.

3000hz?????????? Oh, I have a mess on my hands. I have not even run it that high. I doubt it will get better.

Charles, reflections from room surfaces cause partial cancellations at roughly a quarter wavelength from those surfaces. The dip around 70Hz may be a wall bounce at about a four foot distance(1130 ft. per sec/70 Hz= 16 ft.). Are your speaker drivers about four feet from one or both walls? The dip around 280Hz appears to be a floor bounce similarly calculated arising from about a one foot distance. You need to move your walls and floor.

I agree Jay, Zimm I would experiment on the toe-in angle. Having them aimed right at you narrows the soundstage overall width. Like Mojo, I used to do the same as you. I have found pointing them at a point about 2-3 ft behind me gives me a much better sound stage overall where instruments take of the whole width, and the voices are dead center, appearing to come out of the center channel, as they should. Probably will help your graph dips. Also, you don't want the drivers the same distance form the side and front wall.

Thanks all, I'm going to work on those items first. My speakers are about 22 inches from the side walls, and the same from the front wall. Had not thought about that being a problem. Due to a doorway, I don't have unlimited mobility, but I have some room to adjust some. I'll do that first. I also have some DIY sound absorbers so I'll run it again with those in place at the 1st reflection and see what happens.

Really sad to hear I mis-read 3000hz for 300. Things really look erratic over 250. Ignorance was bliss!
Thanks for the help, one and all.

There is a lot of comb filtering going on at higher frequencies. It is recommended to measure using 1/3 octave smoothing to see what is going on at high frequencies.

Charles, keep in mind that the distances in question(hopefully to be kept as unequal as possible)are measured from the center of the mid-woofer cones, not the speaker enclosure.

Good point thanks. the ratio would be the same, but the measurements would move as i did not use that as the point of measurement. I moved the fronts closer to front wall and reduced the toe angle. Image held pretty well. Still need to re-run graphs.

And I'll add the 1/3 octave change recommended. As is, the chart above 200 looks like my room is about to erupt.

That looks like some good dip, I'll bring the chips.

Chips for EQ processing, I presume?

Just for snacking while we watch him fix it?

ah yes, the dip jokes begin. My room deserves that.
But, as you can see, the folks around here do know a thing or two. While the graphing is frustrating in that every tiny move causes a hole somewhere, while fixing another, it is nice to get big picture changes in a visual format. As a result of JohnK, FredK, and SirQuack (among others) I decided to give the front speakers a move. First, closer together, so as to be further from the side walls (about 32" from mid-driver), while still about 40" from the front, with very little toe-in. Good graph, but the image was weak and the kick drums and bass guitars lost their feel. So I toed in about 5 degrees more. BANG. That was it, the sound-stage got wider than the room, which I did not have before, yet the vocals on "You and your friends" is dead center and clear, and every pluck and kick has a visceral feel. I would not have done this without the recommendations here, as I really felt there was just one sweet spot in my small room. Wow, i have much to learn.
I'm still surprised that decreasing the distance between the speakers and using a wider toe angle actually enlarged the sound-stage, but kept the detail. Man, there are some complex mathematics going on here. Anyway, here is the new graph, although I am not skilled enough to point to the benefits, the auditory changes are unmistakable.

Thank you gentlemen. I owe you a drink on your next trip to N.O. I still owe Tom a beer, but that squirrel seems to be stocked up.
[img][/img]

I'm still not sure that graph will keep pace with inflation.

Zimm I've always been a huge advocate of the importance speaker placement within a room, took me forever to get mine placed where I'm totally happy with the SQ.

I knew it made a difference, but I really didn't get how such small changes make such a big difference. The graph really helps you see that something happened, but you gotta hear it.

I've not tried the graph route yet, but I think I'll pick it up once we get moved into a new space and start thinking about treatments, etc.

That's what I keep saying, too. Here's wishing us both luck on that path to madness.