Room measuring

[Magna Audio]

Can't see the first graphic. Shows broken link for some reason.

1/12 octave is pretty fine res.
Try 1/6 or even 1/3.
At 1/3 you are looking for +/-5dB across the rev range, as a good benchmark.
Even a -5dB plot can't really be heard as missing amplitude as you go down say, a walking bass line.

Bass room modes are pretty sensitive to distance from the drivers.
I can have bass boom a few feet in from the chair, and suck out in the chair!
Try to get a proper length cable, and re-measure.

I've always found with DSP room correction, less is much more.

Better to put up curtains, have thicker rug, books on shelf, even partition a wall etc etc rather than start cutting above 150Hz, or heaven forbid adding amplitude.

'Measures flat, sounds pants', is one of my mantras

[kininigin]

Can't see the first graphic. Shows broken link for some reason.

1/12 octave is pretty fine res.
Try 1/6 or even 1/3.
At 1/3 you are looking for +/-5dB across the rev range, as a good benchmark.
Even a -5dB plot can't really be heard as missing amplitude as you go down say, a walking bass line.

Bass room modes are pretty sensitive to distance from the drivers.
I can have bass boom a few feet in from the chair, and suck out in the chair!
Try to get a proper length cable, and re-measure.

I've always found with DSP room correction, less is much more.

Better to put up curtains, have thicker rug, books on shelf, even partition a wall etc etc rather than start cutting above 150Hz, or heaven forbid adding amplitude.

'Measures flat, sounds pants', is one of my mantras

Oh really, i can see it but maybe it's just me that can for some reason? Let me try again. Yes i'm using 1/12 atm but will try your other suggestions. I think my mic is where my bass dips a bit. In my seated position, i can definitely here more bass. I have ordered a longer cable. Should be here tommorow.

Have no plans to start using eq above 150Hz, if i do use any, it will be bass duties only!

Sorry, so can you see any graphics at all? I've only posted one so far.

[Magna Audio]

I can see the plot.
There's a broken link image before that, perhaps it's not of anything.

Sounds like you are on the right track.

[Mr.Ian]

Rew has a forecast tab that lets you dial in room dimensions and speaker poditions, then generates a forecast of response. Its pretty accurate. U would look at that first, see if moving the subs helps. Next i would try playing with subwoofer phase and crossover level. Go for some big wild changes. Like no subwoofers, 180 degree phase changes try to get able to get a mcheta feel for what effect different changes give. I think you will be able to get a better response before you start to eq

[kininigin]

Rew has a forecast tab that lets you dial in room dimensions and speaker poditions, then generates a forecast of response. Its pretty accurate. U would look at that first, see if moving the subs helps. Next i would try playing with subwoofer phase and crossover level. Go for some big wild changes. Like no subwoofers, 180 degree phase changes try to get able to get a mcheta feel for what effect different changes give. I think you will be able to get a better response before you start to eq

Yes I did see the room simulator but have not used it so far. I can only really move one sub due to layout of the room. Not had a chance to do any more readings but do now have a longer cable. Will try your suggestions sometime next week/weekend or when I get the chance.I'm hoping I can make some difference before thinking of eq'ing.

[bumpy]

Have no plans to start using eq above 150Hz, if i do use any, it will be bass duties only!

Do you still plan to pass the signals above 150Hz through the processor even though you wont be making changes there?

[kininigin]

Do you still plan to pass the signals above 150Hz through the processor even though you wont be making changes there?

Well I don't have a processor atm but if I do get one, I don't think I would pass signals above 150Hz. Maybe would temporarily just to see how it would affect frequency's above that.

[Magna Audio]

I wouldn't use room correction passing the signal though for just room correction!

The benefits of DSP crossovers, steep slopes on the bass channels, no Zobels, no huge inductors and capacitors, no Lpads to volume equal between different drivers and to be able choose between, Linkwitz-Reily, Bessel and Butterworth and choose 1st, 2nd, 3rd, 4th 6th and 8th order steepness , the ability to time align fully etc makes DSP absolutely the right choice for multi way systems.
Passive components to the level required suck dynamics.
Room correction on the deep bass is essential icing on the DSP cake

The level of integration and transparency DSP can offer has to be heard to be believed.
Not necessary for a regular 2 or 3 way passive radiating speaker though.

[kininigin]

I wouldn't use room correction passing the signal though for just room correction!

The benefits of DSP crossovers, steep slopes on the bass channels, no Zobels, no huge inductors and capacitors, no Lpads to volume equal between different drivers and to be able choose between, Linkwitz-Reily, Bessel and Butterworth and choose 1st, 2nd, 3rd, 4th 6th and 8th order steepness , the ability to time align fully etc makes DSP absolutely the right choice for multi way systems.
Passive components to the level required suck dynamics.
Room correction on the deep bass is essential icing on the DSP cake

The level of integration and transparency DSP can offer has to be heard to be believed.
Not necessary for a regular 2 or 3 way passive radiating speaker though.

I don't know what half of those words mean

Maybe i should just buy a DSP processor and see what all the fuss is about! In fact it's not long till my birthday and the missus needs help in choosing a present. Which processor would you recommend?

Got today off, so iv'e taken another measurement but this time i've moved my speakers a bit and have started with the X-Over at 120Hz. Will take two more at 80Hz and 50Hz. Then will move one sub opposite it's current position and repeat.

[IMG][/IMG]

Next to measurements.

[IMG][/IMG]

[IMG][/IMG]

This is the overlayed image of the 3 readings.

[IMG][/IMG]

So it looks like i should be possibly using the the 50Hz or below for my crossover? Would that be anyone else's reading of that?

[Mr.Ian]

My gut reaction is the sub phase needs to invert, but you might just have big null, winding up the sub gain and cutting the lower end might work if your power amps are good.

Personally i would look at sweeps with the subs out then the speakers out and see what they looked like before moving on. With manual eq i found it really helps if one has base infornation on each speaker