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Discussion Starter #1
Hey,

this is my first manual graph no bfd yet how does it look? awful I know.....
 

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You could benefit from a BFD equalizer. I guess you already know that.

If you want an accurate measurement that makes the whole process so much easier, try out REW. Not many things come free these days... this one does...

brucek
 
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Yeah i got a bfd dunno how it works?

do you have to use rew with a bfd?
 
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this is it in a different position, which one is better?
 

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PhilB,

Unless you have the patience of a saint and would get some sort of perverse pleasure from setting up a BFD manually, then I strongly recommend using a PC with the REW software, together with MIDI capabilities.

If you have a desktop PC with a "gaming card" in which you could put a joystick, then the same port can be used for MIDI. Which is what I do. It saves ooodles of time and prevents premature alopecia!

If not you can get a USB MIDI connection. Or if you have a laptop then you will need an external soundcard anyway, so go for one with midi capabilities.

All IMHO!!

Bob
 
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re-done with tones still no rew or bfd though..can u use rew with no spl?
 

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do you have to have a spl connected to the computer to use rew?
 

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do you have to have a spl connected to the computer to use rew?
I'm going to take a wild guess here and assume you mean the word 'microphone' when you say 'spl'.
SPL is an acronym for sound pressure level.

If you're asking whether you could use REW to chart external readings already obtained by some other means, then the answer is yes, if they're in the correct format.

I'll just print out the specific section in the REW HELP file I previously suggested reading.....
I have edited out things that may not pertain to you.

-----------------------------------------------------------

Importing Measurement Data

Frequency Response Text Files

File - Import Measurement command accepts text files in the following formats:

Cubic spline interpolation is used between sample points
Generic comma, TAB or space delimited files
Data must be presented as freq, SPL pairs, one pair per line
Samples can be at arbitrary frequency spacing, but each line must have a higher frequency than the one before and there must be at least 5 freq, spl data pairs
Only lines which begin with a number are imported, others are ignored
In comma-delimited files there must be at least one space after the comma
Spaces before values are ignored
To add a comment on a data line put a tab, comma or space after the spl value
Comma-delimited File Format
Here is an example of a valid format for comma-delimited data:

SPL measurements acquired by Room EQ Wizard V3.08
Source: D:\RoomEQ_Wizard\test files\testfile.txt
Format: Comma delimited data
Dated: 05-Mar-2005 17:53:56
Channel: Left, Bass limited 80Hz

20.0, 65.01
21.0, 65.77
22.0, 67.50
23.0, 67.93
24.0, 68.22
25.0, 67.88
26.0, 67.92
27.0, 68.31, this line has a comment
28.0, 69.14
29.0, 69.16
30.0, 69.29

If comma is used as the decimal delimiter in your locale it is best for clarity to use TAB or space as the separator.

Space-delimited File Format
Here is some data in space-delimited format

SPL measurements acquired by Room EQ Wizard V3.21
Source: D:\RoomEQ_Wizard\test files\testfilespace.txt
Format: Space delimited data
Dated: 27-May-2005 13:03:26
Channel: Left, Bass limited 80Hz

20.0 65.01
21.0 65.77
22.0 67.50
23.0 67.93
24.0 68.22
25.0 67.88
26.0 67.92
27.0 68.31 this line has a comment
28.0 69.14
29.0 69.16 multiple spaces are OK
30.0 69.29

--------------------------------------------------

brucek
 
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Discussion Starter #11
Thanks bruce but that is just gibberish to me! sorry.

I meant a spl meter?

sorry I am so dense....
 

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Am I correct in my assumption that you want to know whether you could use REW to chart external readings already obtained by some other means?

If that's not correct, you'll have to find another way to pose your question, so I know what it is you want to do?

brucek
 

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Hi Phil,

If you want to take measurements with REW you will need to connect your SPL meter to it. You can also use REW to view measurements you have made manually (like those used for the excel spreadsheet) by putting them in a text file, one measurement per line with the frequency and then the SPL value. REW can then still be used to see the effects of filters.
 
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yes thats what i was hoping as i dont have the right sound meter yet. mine does not have the out to the soundcard. It is just a meter.
 

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It is just a meter.
Can you tell us what type of meter it is? Microphones and meters usually require a calibration file for the low frequencies we test at for subwoofers to give meaningful results.

The only calibration files we have on the site are for the three types of Radio Shack meters and one for the Behringer ECM8000. We're also working on a cal file for the Galaxy meters.

If you have a calibration file for your meter, we can tell you how to use it with REW, but if not, I question the validity of the readings...

brucek
 
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Discussion Starter #16
I am now in possesion of the Radio shack 4050 meter, so will plot accurately later!

Thanks for your help, be back soon!!
 

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Gezz Phil, were you up all night with that?!! I see you posted at 7:30 am on a Saturday!!

Anyway, if I were you I'd be pleased with the second graph and be looking to set up the BFD to drop the response between 65 - 110hz to be more in line with the 35 - 55 Hz area. With my recent experience of re-positioning my sub I'd not worry about the peak at about 28Hz. I am now of the opinion that provided you have clean bass, you can never have too much!! Well, you can, but a 7 - 8 db rise at in that area should not be too troublesome for you. Your neighbours maybe, but not you!!!:hush:
 
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Cheers Malice!

When you say second you mean position 2 , 3 or the volume down one? The volume down one is position2 just with the gain down a bit...
 

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Sorry Phil, the spreadsheet opened up showing just two graphs, didn't realise there was one higher up the sheet!

Anyway, this one: sbs12+ position2+volumn down
 
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