First Measurements

**Tommy D** · **01-24-09, 06:49 PM**

Finally got time to do some measurements. I do have some bugs to work out though. Here's what I have so far. The first measurement is with the sub in the middle of the room near field (mic at three inches from cone). The second is near field with the sub in it's location and the third is with the mic at the seating location. I'm using the ECM8000 and UB802. Peerless XLS 12 w/passive radiator. Critiquing well come. Tommy D

**Wayne A. Pflughaupt** · **01-25-09, 07:17 AM**

Looks pretty good for no EQ. Great extension.

Regards,
Wayne

**Tommy D** · **01-25-09, 10:03 AM**

Now we will see what happens when I bring in the mains; Lou C's Cryolites.

I also have a Dayton RSS390 in a 5 cubic ft vented box tuned to 21 hz but I'm only going down to 30 hz. I'll have to drag to the center of the room for a near field measurement. If it wont go any lower I'll have to lower the tuning or seal it and use it for audio. Oh well, that's another project. (Goody!)

I did notice that changing the phase from "0" to 180 degrees had no effect on the response.

Now that it took me several years to get the system to where it is we bought a new house and I get to start all over. My wife doesn't understand my excitement about a new theater. But, she likes the end result. Tommy D

**brucek** · **01-25-09, 10:22 AM**

Quote:

I did notice that changing the phase from "0" to 180 degrees had no effect on the response.

What were you expecting? Changing the phase of a single speaker is the same as clapping with one hand - it's meaningless. Phase effects are only noticed in relation to another speaker, and only over the bandwidth that they share (i.e. crossover).

brucek

**Tommy D** · **01-28-09, 11:48 AM**

So here are the measurements with the mains. The first one is mains only with xo set at 80hz. The second is both sub and mains, again xo at 80hz set at the receiver. I'm not sure about the two dips at 45hz and 100hz. I changed the phase and the graph looks better than before. I guess I need a BFD. As far as the RSS390 goes 30hz is the lowest it will go. I was hoping for lower extension with this set up. It looked good on paper but, reality is a whole different story.

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