Waterfalls

[jheaton]

Hey Guys,

I'm a new user to the software and it seems really cool. I have no idea what its doing but I got all kinda of nice charts to look at now lol jk.

Actually I have a couple of real requestions.

I'm looking for more info (i read the help) on what exactly the Target level is for? I keep thinking in my mind the target level per speaker should be 75db, can't get that out of my mind. I'm following the instructions, it usually sets it anywhere from 73-76 db.

Any known links that will explain how to read the waterfall plots?

Thanks

scott

[Sonnie]

Hey scott and welcome to the Shack!


I like that: "requestions"...

The target level is simply a response line to adjust to. You can set it to whatever you want, but generally if you are using an analog RS meter then 80db is a good number since the needle centers on zero at 80db. After you get your initial measurement sweep you can then "Find Peaks" and "Assign Filters". REW will adjust those peaks to your target line. Of course it's not absolutely perfect everytime... you may wish to adjust those suggested filters and and more filters to get your response as close to the target response as possible. You may have to increase your measurement level a tad to get your measured response up to the target line.

Many of us also will set up the target response line with a house curve... some will set it flat.

Waterfalls but on down in this thread it is explained thuroughly.

[jheaton]

I think I'm still confused on the target level. Is there a difference between running the "set target level..." versus manually setting the target level on the channel.

If I run the wizard it will always pick something close to 75db. If i go manually set it to 80 nothing seems to change, other than i might get an error about peak levels, when running the calibration.

light still isn't on yet

sh

[Sonnie]

heehee... generally you run the "Set TargeT Level" to basically get the target response to level up with what your measurement is going to be. That way it will do the right thing on suggesting filters for you.

What I did when I started out was set the target level per the instructions and it set at 75db (or 76db). Then I decided I wanted to measure it at 80db. So I raised my target level up to 80db. Then when I measured, my response line was below the target level (still at that 75db) and therefore REW wouldn't suggest the right filters. So I had to raise my volume on my receiver a little bit to get the response line on up closer to 80db.

Basically you are simply resetting the measurement level. You can click "Set Measurement Level" and adjust the level to where your RS SPL meter reads 80db. Then reset your "Set Input Volume" and "Calibrate" to make sure REW is consistent with your RS SPL meter. Then when you set your target level it should be around 80db. If it's not then go back and adjust either the "Set Measurement Level" or your receiver's volume to get it to 80db.

The "Set Measurement Level" is basically the same thing as your receiver volume. You can use either/or. Both will adjust the level of the pink noise that you hear.


Have I really got you confused now? Heck, I think I've confused myself!

[brucek]

What I did when I started out was set the target level per the instructions and it set at 75db

I think we should have John modify that to 80....

[Sonnie]

I think he is going to do this on the next release... but I could be mistaken. You know I thought I was wrong once but I was mistaken... I suppose I've got room to be mistaken again.