New Subwoofer installed, help analyzing REW plots

[LarsS]

Installed my first ever subwoofer and need help analyzing and optimizing my setup.

Reason I had to purchase the subwoofer is entirely to blame on my 4 year old granddaughter. Due to her dancing and running I had to save my floorstanders and replace them with my second setup monitor speakers which are more or less impossible to rollover.

Bought an Elac Sub 2050 subwoofer.

 

[LarsS]

Done some initial REW measurements, this is what they look like:

Without Sub installed :

 

[LarsS]

With Subwoofer installed (Blue) LP 70, Vol 50:

 

[LarsS]

Waterfall w sub:

 

[Purité Audio]

I find if I go to ‘graphs’ and hit the 1/48 smoothing button the plots are easier to look at.
Keith

 

[Krunok]

With Subwoofer installed (Blue) LP 70, Vol 50:

View attachment 18709

If that is a single log sweep measurement taken from your listening position than it looks as your subwoofer is doing a good job. You would get much better picture if you make at least 5 log sweeps from various positions around your listening position, average them and apply 1/12 smoothing.

Or, even better, you can do a RTA sweep by moving the mic around your listening position. It's explained here.
This post will also give you a basic idea.

 

[Ron Texas]

Both the mains and the sub are responding to the room in a similar way. Try moving the sub somewhere else to see if that tends to flatten things out a little.

 

[Krunok]

Both the mains and the sub are responding to the room in a similar way. Try moving the sub somewhere else to see if that tends to flatten things out a little.

If this is a single log sweep measurement it cannot be flat be flat at any position. Single sweep would hardly be flat even with Room EQ in place.

 

[Ron Texas]

If this is a single log sweep measurement it cannot be flat be flat at any position. Single sweep would hardly be flat even with Room EQ in place.

What I am thinking is the sub and mains might respond differently with the sum being flatter than it is now. If the measurement method is deficient, use a different method.

 

[Krunok]

What I am thinking is the sub and mains might respond differently with the sum being flatter than it is now. If the measurement method is deficient, use a different method.

You cannot rule out this position without proper measurement. When you look at the photo with that cornered wall and the door I doubt this can be any flatter without room EQ. But nothing can really be concluded from a single sweep.

 

[LarsS]

Thx all,

I'll do some more measurements tomorrow, not allowed to measure any more tonight.

Below you can see current setup, I'll see if I can replace the rack with a smaller one and have the sub in between the speakers.

 

[Ron Texas]

That's a nice room. I bet there are piles of snow outside, something that doesn't happen here.

 

[Ron Texas]

You cannot rule out this position without proper measurement. When you look at the photo with that cornered wall and the door I doubt this can be any flatter without room EQ. But nothing can really be concluded from a single sweep.

I found moving my sub around made a huge difference. I used this: http://www.szynalski.com/tone-generator/ if I heard the volume change as I stepped through the frequencies it gave me an indication of what was happening. The variation was audible, by definition. I don't have test equipment or a calibrated microphone and probably would not know how to use it if I had one. It's an unscientific trial and error process, but it produced results.

 

[Krunok]

I found moving my sub around made a huge difference. I used this: http://www.szynalski.com/tone-generator/ if I heard the volume change as I stepped through the frequencies it gave me an indication of what was happening. The variation was audible, by definition. I don't have test equipment or a calibrated microphone and probably would not know how to use it if I had one. It's an unscientific trial and error process, but it produced results.

Trial and error is a legit scientific process.
Your equipment would do even better if you measure it properly and do room EQ. I'm sure you can do it, it's not a rocket science.

 

[Krunok]

Thx all,

I'll do some more measurements tomorrow, not allowed to measure any more tonight.

Below you can see current setup, I'll see if I can replace the rack with a smaller one and have the sub in between the speakers.

View attachment 18718

Your setup looks very nice and having fireplace between speakers is awesome!

 

[LarsS]

Subwoofer now moved into final position in between speakers. New smaller HiFi bench (Ikea!) installed to accomodate space for the subwoofer.

- Eight (8) new REW measurements, 1/12 smoothing applied.
- Low Pass set to 70 Hz.
- Volume set to 50.

Average SPL&Phase:

 

[LarsS]

Waterfall from 1'st measurement:

 

[LarsS]

Impulse from 1'st measurement:

 

[LarsS]

Decay from 1'st measurement:

 

[Krunok]

Subwoofer now moved into final position in between speakers. New smaller HiFi bench (Ikea!) installed to accomodate space for the subwoofer.

- Eight (8) new REW measurements, 1/12 smoothing applied.
- Low Pass set to 70 Hz.
- Volume set to 50.

Average SPL&Phase:

View attachment 18753

This is average of 8 log sweeps? Where was the mic in each position?