Alright, what am I doing wrong (or right)?

**05-04-08, 02:29 AM**

Using a 2807 as pre with an ext SB card. Subs co-located in a(n) not too optimal location but the only available spot at this time. Mainly sitting in a 'null' located about 11' out from long side on the right wall in a 20'x40' room w/cathedral ceiling, open not sealed.

Planning to use an fbq2496 to smooth things out (it's actually sitting in the box right now, mocking me as I type)

Sooo...

**brucek** · **05-04-08, 07:55 AM**

You've demonstrated how important graph scale is...

The standard scale to use for subwoofer measurements is vertical of 45dB-105dB and horizontal of 15Hz-200Hz. Give that a try before you carry on. Use a target of 75dB.

brucek

**thewire** · **05-04-08, 05:35 PM**

How many subwoofers? What are they?

**05-05-08, 12:54 AM**

Quote:

brucek wrote:

You've demonstrated how important graph scale is...

The standard scale to use for subwoofer measurements is vertical of 45dB-105dB and horizontal of 15Hz-200Hz. Give that a try before you carry on. Use a target of 75dB.

brucek

Sorry

I was playing around with the graphing and kinda forgot to re-apply. Thanks for the reminder.

A little better perspective.

**05-05-08, 01:00 AM**

Quote:

thewire wrote:

How many subwoofers? What are they?

2x AV123 MFW-15's

**brucek** · **05-05-08, 07:36 AM**

You don't seem to have any peaks, but it's a bit humped between about 25Hz - 55Hz. A broad filter would likely take care of that. I wonder if moving your subs around and/or apart would solve that problem and you wouldn't need any EQ?

brucek

**Wayne A. Pflughaupt** · **05-05-08, 10:36 AM**

Quote:

Tcr wrote:

Sorry

I was playing around with the graphing and kinda forgot to re-apply. Thanks for the reminder.

A little better perspective.

Ted, that looks like a highly smoothed graph. Make sure it's set for no smoothing. Look for the "Smoothing (octaves)" dropdown under the "Trace Adjustment" button on the left side of the screen

Regards,
Wayne

**05-06-08, 01:51 AM**

Quote:

Wayne A. Pflughaupt wrote:

Ted, that looks like a highly smoothed graph. Make sure it's set for no smoothing. Look for the "Smoothing (octaves)" dropdown under the "Trace Adjustment" button on the left side of the screen

Regards,
Wayne

Thanks Brucek and Wayne. Same measurements without 1/3 octave smoothing applied. I'll post some more measurements in a couple of days with a couple of changes in setup.

Anything else you guys can think of?

**brucek** · **05-06-08, 08:12 AM**

Quote:

Anything else you guys can think of?

Measure at 75dB. Your level is quite high above target.....

brucek

**05-25-08, 05:34 PM**

Sorry it took so long guys... but you know

Anyway I still don't completely understand some things.

How is it when I set rew @75db @-10 on my AVR I get this v. this with -20?

Still have a dip @55 & 75 but should I eq down from, say, 23hz to 74hz to level this out?

Then raise overall to set levels

**Blaser** · **05-25-08, 05:50 PM**

The graphs look good. Only 2 peaks to be tamed a bit and you're OK. I don't understand your first question.

**05-25-08, 06:47 PM**

Quote:

Blaser wrote:

The graphs look good. Only 2 peaks to be tamed a bit and you're OK. I don't understand your first question.

I guess that I think it looks more level at higher spl levels. Still has the same major peaks but looks like around 25-50 level out better?

**Blaser** · **05-25-08, 06:50 PM**

Are you sure the mic is in the same position? There shouldn't be that much difference.

**05-25-08, 07:02 PM**

Quote:

Blaser wrote:

Are you sure the mic is in the same position? There shouldn't be that much difference.

Yeah. Tried many, many different positions. Those are the absolutely the same just with higher volume. Pretty much the same sig, just expanded a bit.

Here's one from a pretty bad positioning

**salvasol** · **05-25-08, 07:24 PM**

Quote:

Blaser wrote:

Are you sure the mic is in the same position? There shouldn't be that much difference.

What about the SPL calibration??? ... I think you need to adjust the SPL reading anytime you change the volume, Right??? ... (if -10 was @75db, -20 will be less than 75, Right???)

**05-25-08, 09:30 PM**

Right. Boy, this is gonna be tough. I haven't even started running the fbq2496 yet. Where's that "pulling your hair out" icon at?

**salvasol** · **05-26-08, 01:31 AM**

Quote:

Tcr wrote:

... Where's that "pulling your hair out" icon at?

Here you go

.............

**05-26-08, 01:50 AM**

Quote:

salvasol wrote:

Here you go

.............

Rotfl!!!! Thanks salvasol! I needed that.

**Blaser** · **05-26-08, 04:41 AM**

Quote:

salvasol wrote:

What about the SPL calibration??? ... I think you need to adjust the SPL reading anytime you change the volume, Right??? ... (if -10 was @75db, -20 will be less than 75, Right???)

Yes you're right. But FYI, this is mainly in order to enable REW assign the necessary filters above the target line. You can also move the target line up or down to let it do its job. But if it just to have an idea about FR, it is not really a must as far as it is the shape of the curve that is of interst

Advertisement