Metric Halo SpectraFoo - Manual (Page 57)

The Transfer Function
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This means that the time between Time ”0” and the first
spike in the impulse response is the delay between the
source and the response signals. If you move the cursor
of the delay finder to the first spike you will delay the
source signal by the appropriate amount to time align
the source and response signals.
The impulse response is essentially noise for all times
before the impulse has propagated through the system
being tested.
All of the other spikes present in the impulse response are the time delays of the various “reflections” in the system.
These can be real reflections from walls, tables, etc. or they could be virtual reflections from the digital delays in a
reverb algorithm or electrical reflections due to improperly terminated studio wiring.
Cursor
Time ”0”
Figure 4.3: Time Aligning the measurement with the Delay Finder Window
• The delay readouts provide precise information about the relative delay between the left and right chan-
nels for the current cursor position. This information is provided in samples, milliseconds, and in feet
(assuming standard temperature, humidity and pressure). The maximum inter-channel delay supported
by SpectraFoo is about 750 milliseconds.
• The Make Capture button will transform the impulse into a capture that can be analyzed using
SpectraFoo's other instruments. Analyzing captures is covered in the Capture and Storage section.
• The Rename Window button will allow you to give the impulse a unique name. This is useful when
taking multiple measurements to compare.
• The magnifying glass buttons will zoom in and out of the timescale, as will the small window scrollbar.