Understanding Phase Response

[Sonder]

Hello, could anybody point me in the direction of information regarding the phase response, and how do I interpret this, has anyone done a tutorial or does anybody have any documentation on this, I could not find any information in the some guides and acoustic measurement page, or is it the case that I do not really need to interpret this trace, as it is mainly for aligning sub speakers?

Many thanks

 

[EarlK]

You'll very likely learn more about phase if you simply get on with trying to align the phase between your different drivers ( iow: learn by doing ).

Read all the current threads that jtalden has participated in ( that'll act as your primer before you do your own system ).

I mean , I could tell you how phase is derived mathematically ( for any captured frequency response > since phase isn't measured directly > it's a derivative of frequency & the change of frequency ) but what does that info really give you ( when you really just want drivers to add together instead of them working against each other ) ???

 

[Sonder]

Thanks for the information, when you say align the drivers, are you talking about the drivers in a single cabinet, or separate speakers within a room?

 

[EarlK]

Thanks for the information, when you say align the drivers, are you talking about the drivers in a single cabinet, or separate speakers within a room?

Phase ( issues ) applies equally to both mentioned scenarios.

 

[Sonder]

Thanks, so when I am at trying to align drivers where can I overlay the phase response so I can view both on the same graph?

 

[EarlK]

Thanks, so when I am at trying to align drivers where can I overlay the phase response so I can view both on the same graph?

I use XSim ( free crossover design software ) when I want to try to align the drivers used within a passive ( crossovered ) speaker box .

If you are talking about aligning individual drivers within a speaker box that's using an active crossover then REW is the best software to accomplish this.

Again, do your home work and study jtalden's posts ( forum contributions for the last year ) on aligning drivers within REW ( he's covered this territory multiple times >> all very thoroughly ).

 

[jtalden]

Phase can be helpful is several different situations, but it is not a necessary concern for most common setup efforts. Please tell us a little more about your setup and objective so that we can provide a response that is appropriate in your situation.

The REW alignment tool is helpful for most situations and is discussed here.
The phase overlay chart is also helpful.

 

[Sonder]

Thanks for the replies, I am coming to this from Smaart software which shows a realtime trace of the phase for sub alignment.

 

[jtalden]

I don't use Smaart software, but assuming you are interested in driver to driver XO timing as in; SW to mains or MR to TW. The linked thread above discusses measurement and analysis methods. REW Help provides the description of action of the control buttons themselves.

 

[Sonder]

Many thanks, yes I am reading a lot of the manual now, and referencing your threads, really insightful.