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Discussion Starter #1
Hi!

I'm new to rew so maybe it is a noob question but I don't find this problem anywhere in this forum...

I'm successfully doing calibration and measurement after that the graph's appearing but with only phase measurement .. nothing else even if I click on spl under the graph..

On the folder left sided I can see the graph but in thumbnail format only ... is it me or a bug?

Thanx
 

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I suspect a problem with your SPL calibration is resulting in your graph being off the top of the range - if you put the graph cursor within the measured range you can see what the SPL value is. If that is the case you will just need to do the SPL calibration, per the help to fix future measurements, for that one you could offset the result using the graph controls (gear icon to top right of graph) to get it back within range.
 

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Discussion Starter #5
Thank you,

What do you think i should put more or less as numbers in the offset box?

I have absolutely no idea what it is:)
 

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Put the cursor somewhere in the measurement range (at 40 Hz, for example) and read the SPL value from the graph legend. Then you will know how much is needed to get it into a sensible range, like 75 dB or so.
 

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Discussion Starter #7
Hi John

I didn't succeed to make it appear :(

Even when i'm calibrating the sound card (with only the internal loop) when i'm hitting the measurement button ,there is nothing appearing in the main frame except phase..

I tried the offset like you said but still nothing.

Any other idea?
 

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Hi John

I didn't succeed to make it appear :(

Even when i'm calibrating the sound card (with only the internal loop) when i'm hitting the measurement button ,there is nothing appearing in the main frame except phase..

I tried the offset like you said but still nothing.

Any other idea?

The maximum offset value is limited to +/-100db ( per entry ).

So do the offset entry 3 times ( and your trace will appear at around 55db ).

It works. I just tried it on the file you posted.

:)
 

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Discussion Starter #11
Ok great,

I'm sorry i'm very noob on this:)

What do you mean by "do the offset entry 3 times"?

:whistling:
 

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Please attach the mdat file for the measurement.
Hi John,

I'm just piggy-backing on the OP's thread (as my question is related) - I hope you don't mind.

I have got both the 'SPL Graph' and the 'SPL/Phase Graph' appearing OK ... but the result is a mass of spikes! :frown:

In the "Getting Graphs Ready to Post" thread, by 'Sonnie', it says "1/3 or 1/6-octave smoothing is beneficial" - can you tell me where I select this?


Thanks,
Andy
 

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Smoothing is in the Graph menu, but best make sure you have a valid measurement first. Happy to check the mdat file for a measurement if you attach it.
 

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Smoothing is in the Graph menu, but best make sure you have a valid measurement first. Happy to check the mdat file for a measurement if you attach it.
Thanks, John - will do this in about 8 hours time, when I get home from work.

Andy
 

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Smoothing is in the Graph menu, but best make sure you have a valid measurement first. Happy to check the mdat file for a measurement if you attach it.
Hi John,

Yes, I found the smoothing - thanks.

But I don't have a valid mdat file atm - so will re-post when I have one. (This will be at the w/e - maybe even tomorrow evening, our time - as I have to cart my computer up 2 floors, to where the hifi system is, to take a measurement. :frown: )

But I have another problem. The X-axis on the SPL graphs I did generate, doesn't go from 10 - 30Khz ... or even 20 - 20Khz. I can see the "Limits" tab at the top right; this doesn't seem to actually do much to the horizontal axis, when I change the numbers? Is there any other place to set 10hz - 30Khz?


Thanks,
Andy
 

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Smoothing is in the Graph menu, but best make sure you have a valid measurement first. Happy to check the mdat file for a measurement if you attach it.
Yes, thanks, John - I have now applied 1/6th and 1/3rd smoothing! :T

Have attached the mdat files ... do I appear to be on the right track?

The 1/3rd smoothing graph seems to be useful enough to show me I need to apply some PEQ in my miniDSP software, to flatten the peaks which are occurring at 650hz and 15Khz ... and possibly also around 4Khz? Do you agree?

But I am confused by the rise that the mic is showing, from 300hz downwards. I had several people over for a listen, yesterday, and they all thought the sub integration was excellent - as you weren't aware the subs (which are crossed over with the mains at 100hz, 24dB HP & LP) were ever working! :smile: Yet from the massive rise shown by the graph at LFs ... you would think the bass would've been overwhelming! :eek:

Or is this the Fletcher-Munson curve at work here ... the mic picks up a massive rise in dB at LFs but the ear doesn't hear it like this?


Thanks,
Andy
 

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Measurement looks fine. Resonances are well controlled in the room. You don't need to save the file with different smoothing settings, smoothing can be changed back and forth between settings as desired.

I wouldn't personally apply EQ much above 150 Hz or so as responses vary dramatically with position, if there were a very broad feature of the response that showed some commonality across the listening area then it could be worth experimenting, it would mainly be a tonal adjustment in that case.

There is quite a rise at the low end, though I've seen greater on occasion. Audibility depends on content and to some degree on adaptation, if you adjusted the subs to be lower and left them that way for a few days then you might find returning to the current level a little bass heavy, or you might find it just right. Personal preference is a big factor.
 

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Measurement looks fine. Resonances are well controlled in the room.
Thanks, John. A mate with some knowledge of acoustics suggests the rise I am getting at 15K is caused by the glass 'cafe doors' I have at one end of the room ... so I will experiment with a temporary drape (tape a sheet over the glass) - if it takes that rise away, I'll invest in some open-weave curtains. :smile:

There is quite a rise at the low end, though I've seen greater on occasion. Audibility depends on content and to some degree on adaptation, if you adjusted the subs to be lower and left them that way for a few days then you might find returning to the current level a little bass heavy, or you might find it just right. Personal preference is a big factor.
Thanks - I'll put my paranoia away and do some experimentation.

Regards,
Andy
 
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