# REW with HDMI: How to set Sub and LR?



## hifikid80 (May 30, 2016)

Hi,

I am not sure how to set up the channels for the measurement. People recommend taking measurements for SUB with L and R together. How do i set it exactly? , in the output I select HDMI 4 (LFE) and in the timing reference output should i change to Left and Right? .

And in the REW spl meter which one should i select eg A or C or Z, and F or S when checking levels?

Please help.

Thanks


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## JohnM (Apr 11, 2006)

Select left as the main output and right as the reference output, your processor's bass redirection will send the appropriate content to the sub assuming your mains are not full range. For level checks the SPL meter should be C-weighted, Slow.


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## hifikid80 (May 30, 2016)

Ok ..so I get Output from all three right?. If I want to measure only one ( Sub or left or right) then what should I set in Timing reference?. 

Thanks


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## JohnM (Apr 11, 2006)

If you are making measurements with the acoustic timing reference, set one channel (e.g. left) as the timing reference and then measure each channel individually. To see what the result would be for more than one channel you can sum them using the Trace Arithmetic feature in the controls of the All SPL graph. You will need to subtract 10 dB from measurements of HDMI 4 (LFE) as the receiver adds 10 dB of gain to the LFE channel.

Alternatively use the Java drivers and you can then select to measure left, right or both together.


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## needspeed52 (Aug 2, 2008)

Hello Jon, I haven't used REW for months and I just downloaded the latest version 5.16 and I'm a little confused, I just want to take spl reading for example L + R, I know that the base will be sent to the subs so I will get the L + R + subs measurements, how do I do this without using the timing reference option, can I disable the timing reference and just take the L + R + subs FR measurements? Forgive my ignorance but like I said it seems like a lot has changed with the newer versions of REW especially with the Timing Reference option measurement. I don't want to take the measurement you described in the previous post by selecting the left speaker as the reference and going from there, I just want to do what I've always done with measuring L + R + subs. TIA


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## JohnM (Apr 11, 2006)

As above:


JohnM said:


> use the Java drivers and you can then select to measure left, right or both together.


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