Home Theater Forum and Systems banner

1 - 3 of 3 Posts

·
Registered
Joined
·
1,405 Posts
Discussion Starter #1
I applogize that this is very confussing so I really don't know a good way to ask so here is best I can figure. If something doesn't make since I will try to clarify best possible.

I am trying to examine the subwoofer signal and full bandwidth pink noise of an external source, my XA2. I do not want to hook up directly to the XA2 again as I have done this, and I don't have a receiver. The disc I am using in DVE. When I look at the signal level when using an REW subwoofer signal to calibrate the SPL it reads about 92dB. So I then took the external signal in DVE and used this to calibrate the SPL meter in DVE, by looking at my meter to read 75dB. Then I look at the RTA and the signal shows up very low. Because the signal in DVE is I beleave (according to online manual) -33dB FS or -30dB FS depending on what I am looking at, I add an offset of -30dB FS or -33dB FS to the measurement. Then I have corrected for the SPL meter and for the extra -3dB. Is this correct?

According to the directions the meter should read 75dB for the subwoofer, and when I calibrate the SPL my measurements in REW, it says the signal level taget is much higher, but it tracks at near the 75dB target. The REW SPL meter also says the signal is higher. When I am done using the external source I go back to REW and the signal there says it is at 85dB with an output level of 5 in my vista mixer console, and an input of near 1. When I use a single subwoofer the level in REW at the same setting says 75dB.

Am I adding the offset correctly to examine the RTA using a standard -30dB FS offset or do I use -33dB FS since I think the DVE uses this. :dontknow: Do I not use the SPL meter correction in REW since the disk does not or are the frequencies used to balance the level not neccessary as oppossed to REW where this would be neccessary? :gulp:
 

·
Registered
Joined
·
1,405 Posts
Discussion Starter #3
Alright so I'm looking at the RTA while a movie is playing trying to figure out what is going on. Playing with subwoofer position trying to get optimal transients etc. I used the high frequency keyboard notes in the show "24" theme song to experement with getting a good stereo effect the other night. That seemed to work pretty well but I wanted to see what it looked like in another position and aiming them differently. Two 12" woofers are in the front left corner and two in the back right corner. Starting to get frustrated like I may want to move the rear subs to the front, add tons more insulation to my ceiling maybe. I add +30dB (optional) to the offset and use scale -70 dB FS to 0dB FS, or do nothing. Is that correct?

Graph with offset bellow
 

Attachments

1 - 3 of 3 Posts
Top