[DrWho]

brucek wrote:

Yes, you will get a nicer looking graph, but it's not representative of the rooms response for the sub.

Well, it's more representative than the default windowing.

Generally you want to adjust the window widths to include all of the response up to the point where it disappears into the noise of the impulse.

And if you look at the windowing of this particular impulse response you'll notice that I did just that.

This is why for a sub John chose 125ms as the pre ref window and 500ms as the post ref window for defaults. He also indicates that Tukey 0.25 is the best default for subs.

There is no way anyone can choose a proper window without first interpreting the data. Even with the same speakers no two rooms are going to have the same impulse response, nor the same noise floor.

The Tukey 0.25 is going to show you more of what the sum of the speaker + room is doing, where something like Blackman-Harris is going to show less of what the room is doing. Depending on what problems you're looking to deal with and what the Impulse Response looks like will determine what kind of windowing provides the most useful data. There are no absolutes in this regard, so I'm sure there are plenty of opinions with different ways to approach the situation. In other words, conclusions about the measurements must take into account the windowing for the conclusions to have meaning.