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lukescroggin
October 8th, 2008, 04:51 PM
I'm new to this forum and Smaart V6 and seems like the delay measurements are giving everyone trouble but I thought I would try to get some help myself here. I'm using a firewire 1814 interface right now and I'm trying to time align some front fills with our main array and for some reason I always get zero for the delay time in the IR analysis. when I go to calculate delay in the main window it is very accurate but I don't know if i'm making some stupid mistake in the IR analysis window or what but if anyone has any ideas for what's going on...thanks

Arthur Skudra
October 8th, 2008, 10:03 PM
Can you clarify something here...are you getting believable delay times using the auto locater (Auto Small or Auto Large buttons)? In the IR analysis window, can you describe what kind of trace you're seeing there? Make sure you have your inputs routed correctly into your interface, perhaps you can describe your setup in further detail?

Edit:
I should clarify that there is nothing wrong with the way Smaart determines the delay time, it simply looks for the tallest peak in the impulse response, and sets the time delay accordingly. Whether that "tallest peak" is the direct field or not has more to do with what lies between the keyboard and the back of the chair! ;)

Harry Brill Jr.
October 8th, 2008, 11:42 PM
I want to make it clear the only time I've ever had an issue getting delay times in the delay finder is in a room with stronger lateral reflections than the direct signal. This is a somewhat rare occurrence and a visit to the impulse response and some carpet added to the floor of the room (a few weeks later) solved that problem. Please provide more detail or we cannot help you. Some of us really enjoy helping out but these vague posts are like asking someone "How long is a string?"

Calvert Dayton
October 10th, 2008, 12:37 PM
I'm new to this forum and Smaart V6 and seems like the delay measurements are giving everyone trouble...

Mmmm, not really. Seems like 9 times out of 10, if someone is having trouble getting a delay measurement it's because they've always just used Smaart as an RTA and never really got their arms around dual-channel measurements. There were however, a couple of actual delay-related bugs in Smaart 6.o, one of which was completely fixed (as far as we know) and the other mostly fixed in 6.1. So if you're using 6.o I would definitely recommend grabbing the update from the EAW web site at your earliest possible convenience.

The bug that was mostly fixed actually sounds like it could be your problem. You could run afoul of that one if you were using a multi-channel interface and using something other than the first two input channels on the device as your inputs for Smaart. In 6.o, IR Analysis would never under any circumstances pull data from any input channels except the first two in the list. The same problem could affect auto-delay locator operations in 6.o but that was completely fixed in 6.1.

Both problems were discovered like a week or two before Adam abandoned me as the Smaart programmer at EAW, so we only had time to half fix the IR Analysis part. What's still broken is that if you change input pairs while the IR window is open, you have to close and re-open that window for the change to be recognized.

I have also seen some strange things happen with delay measurements in Smaart 6 when a user preferences file became corrupted somehow. This is fairly rare but deleting your current sm6user.plist file and letting the program build a new one on the next run is an easy thing to try.

PhillipIvanPietruschka
October 10th, 2008, 11:40 PM
The only times I have had issues getting accurate Delay times (and well, all measurement Data) is when the interface (Digidesign 002) didn't want to play nice with my laptop. Changed the interface and the problem dissapeard. FIW, the problems weren't unique to Smaart, even iTunes had problems.

Every other scenario and interface I've used has seen reliable results.