What's the order for speaker measurements?

[sirenjunkies]

Hi folks

I've just started using REW and would appreciate your feedback on a few 'newbie' questions:

1. Measuring The Lows
When measuring the low freq's, I've been running the sub and full range speakers and rolling test signal off at 200 Hz. Is is correct to use all speakers or should I use the sub only? (Bearing in mind, the sub xover is at 75 Hz with the main speakers).

2. Measuring Full Range
Ok, the logical assumption is to run the sub and the 2 full range speakers while measuring the full range (which is what I've been doing). Is there any value in testing each FR speaker individually? I imagine the interaction between all speakers running is going to show up problem areas (modes/peaks/dips) better.

3. House Curve
I've read the in-depth posts on this: very interesting and thanks to the contributors. I loaded one of these low freq curves (starts 31.5 Hz @ 0, to 160 Hz @ -17.5) into REW and it plots as a LF upward scoop when viewing the full range EQ response. If I match my low end to this, I've got a bucket-load of bass. Is this correct?

Any replies much appreciated

Siren
ps the depth of knowledge on this forum regarding REW is bordering on staggering for me.

[brucek]

1. Measuring The Lows
When measuring the low freq's, I've been running the sub and full range speakers and rolling test signal off at 200 Hz. Is is correct to use all speakers or should I use the sub only?

Initially, it's best to measure the sub alone without the mains. This allows you to get a response without any other influences, and allows you to equalize the subwoofer (if that's the intent) without the effect of interactions with other speakers. The receiver is set in stereo mode with all soundfields and eq turned off and the mains speakers disconnected.
Then you can add the mains and see how they mix with the sub, especially around the crossover.

2. Measuring Full Range
Ok, the logical assumption is to run the sub and the 2 full range speakers while measuring the full range (which is what I've been doing). Is there any value in testing each FR speaker individually?

Normally, only the sub and the sub+mains is measured when REW software is used. Remember that if you are going to test full range, that a Radio Shack meter is not suffice. You'll need a full range microphone such as the ECM8000.

3. House Curve
I've read the in-depth posts on this: very interesting and thanks to the contributors. I loaded one of these low freq curves (starts 31.5 Hz @ 0, to 160 Hz @ -17.5) into REW and it plots as a LF upward scoop when viewing the full range EQ response. If I match my low end to this, I've got a bucket-load of bass. Is this correct?

Personally, I'm not a fan of these 'negative' house curve value. I like to start at the crossover at zero, and then offer a modest rise to about 30Hz of about 5dB to 8dB.I then match the mains to join with the sub at the crossover at the same level. This then says that you'll have a reasonable rise from the crossover down to 30Hz of 5dB to 8dB. Not a bucket, just a shot glass............

brucek

[sirenjunkies]

Hi BruceK

Thanks for the advice. I'll go and have a play and see what happens.

Siren