====== Alignment ======

----
Use Overlays to see the impulse response for multiple measurements in one view.
===== Measurements timing information =====
=== Measurement without timing ===

If a measurement was done without the option: “Use accoustic timing reference” there is no timing information and aligning is not required. REW will automatically have the Pulse Responses starting at 0 ms. 
{{ :audio:rew:rew-impulse-response-no-timing-ref.jpg?400 |}}
=== Measurement with timing ===
If a measurement was done with the option: “Use accoustic timing reference” there is timing information and aligning might be required. REW will show timing information with the Pulse Responses. 
{{ :audio:rew:rew-impulse-response-with-timing-ref.jpg?400 |}}

===== Set t=0 Manually =====
You can manually define the t=0 for a particular measurement, by the following steps:
  - Select the proper measurement and select the "Impulse" tab. 
  - Press action and put the curser where t=0 should be
  - Press "Set t=0 at cursor"

{{ :audio:rew:rew-adjust-pulse-timing-2.jpg?600 |}}

===== Shift Adjust Manually =====
You can manually define an offset for a particular measurement, by the following steps:
  - Select the proper measurement and select the "Impulse" tab. 
  - Press action 
  - Press "Offset t=0"
  - Adjust the offset
{{ :audio:rew:rew-adjust-pulse-timing-1.jpg?600 |}}

===== Cross Correlation Align =====
REW can automatically time align several measurements, by the following steps:
  - In the "All SPL" tab select all the measurements that need to be aligned
  - Put the measurement that is at t=0 at the top of the measurement list. REW will align all selected measurements to the first selected measurement.
  - You can open an overlay with the impulse responses to see the effect of the alignment.
  - Press "Cross Corr Align"
{{ :audio:rew:rew-adjust-pulse-timing-3a.jpg?600 |}}
{{ :audio:rew:rew-adjust-pulse-timing-3b.jpg?600 |}}