Did you Calibrate SPL and Set Target Level at 75dB?
Can you show me the Impulse response graph.
Can you show me your REW Settings/Soundcard tab.
brucek
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Yes I did calibrate SPL, it was fairly high though 96.
I went to collect the data for you and everything ran fine this time.
I'm little confused over what levels I can adjust on the soundcard (External USB with analog controls in my case) after I have calibrated the sound card. Can I change Mic input sensitivity and output level? I would assume I could because these devices have no relation to loopback levels.
What should I target the handheld SPL Meter for (i.e. Stereo system volume) during REW SPL calibration?
If I target 75, then when I measure it says signal is way too low. So I end up calibrating fairly.
I keep playing with Speaker Output and Mic sensitivty I sometimes think I'm lopsided and cause problems.
Last night when I had trouble I was calibrated at SPL 96, this morning I calibrated at 85.
I still attached what you asked in case you see anything wrong. I did an impulse with speaker connected and one with out to get a baseline of what the Mic was picking up with no signal. Last night it was much uglier than what's attached. Way less flat with big peaks punching through at 60.
Thanks for the quick response.
I went to collect the data for you and everything ran fine this time.
I'm little confused over what levels I can adjust on the soundcard (External USB with analog controls in my case) after I have calibrated the sound card. Can I change Mic input sensitivity and output level? I would assume I could because these devices have no relation to loopback levels.
What should I target the handheld SPL Meter for (i.e. Stereo system volume) during REW SPL calibration?
If I target 75, then when I measure it says signal is way too low. So I end up calibrating fairly.
I keep playing with Speaker Output and Mic sensitivty I sometimes think I'm lopsided and cause problems.
Last night when I had trouble I was calibrated at SPL 96, this morning I calibrated at 85.
I still attached what you asked in case you see anything wrong. I did an impulse with speaker connected and one with out to get a baseline of what the Mic was picking up with no signal. Last night it was much uglier than what's attached. Way less flat with big peaks punching through at 60.
Thanks for the quick response.
Attachments
You are supposed to set it to 75db.....
Hopefully, you've read the REW HELP FILES......
With the mic connected to the line-in, and the line-out going to the receivers AUX in, and the receiver in stereo mode, with the mains disconnected so the sub only is playing, then when you run the Check Levels routine, set the SPL level in the room to 75dB at the listening position with the receivers volume control (after you have the REW output level set properly as seen below.
Then when you get to the part in the Check levels routine where you set the input level, set it to -12dB as shown in the pic below.
Then run the Calibrate SPL and set to 75dB..
Measure.
THis shows the interaction of the Windows mixer and the controls in REW
This shows the REW controls and the input output effects.
brucek
Looks like you are running Vista so you won't have the same mixer setup as windows. Right click the system tray volume icon when REW is running and select "Open Volume Mixer", make sure the volume control for REW is at the top.
The reason for the offset in the soundcard cal would be having the levels set higher than the reference level during cal. A screenshot of the Impulse Controls graph page after doing a loopback will verify that all is OK for that measurement. Beyond that it will be a case of getting the input level on your TASCAM set correctly. If you use the RS SPL meter then that is a direct line level input and might be an easier way to get going than having to tweak the mic input gain with the ECM.
The reason for the offset in the soundcard cal would be having the levels set higher than the reference level during cal. A screenshot of the Impulse Controls graph page after doing a loopback will verify that all is OK for that measurement. Beyond that it will be a case of getting the input level on your TASCAM set correctly. If you use the RS SPL meter then that is a direct line level input and might be an easier way to get going than having to tweak the mic input gain with the ECM.
Attachments
Not at all. It can be anything you like.
Since we spend a lot of time evaluating and comparing responses here, it's nice to have a pseudo standard so everyone is on the same page. So we came up with a standard set of vertical and horizontal axis with a reasonable swing of 60dB that allows a +/-30dB swing around a 75dB target.
It works quite well and everyone seems game to comply.
But sure, if you like 84dB - fill your boots....
brucek
Ah ok, so when measuring the SPL during SPL CAL you want 75 on the Meter in hand too so we are all on the same scale. Tha tmakes sense.Not at all. It can be anything you like.
Since we spend a lot of time evaluating and comparing responses here, it's nice to have a pseudo standard so everyone is on the same page. So we came up with a standard set of vertical and horizontal axis with a reasonable swing of 60dB that allows a +/-30dB swing around a 75dB target.
It works quite well and everyone seems game to comply.
But sure, if you like 84dB - fill your boots....
brucek
But when I do that I tend to get too low a level sometimes and can't turn gain up much more on the Mic.
I'll try again now that I'm more comfortable with the software.
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