Rational Acoustics



Kip Conner
December 4th, 2008, 01:31 PM
This would really go with any subwoofer with a processor.

I'm a firm believer in Meyer. When they set out to do something they pretty get it right before passing it on to the consumer. Therefore, I use the prescribed processor for the product that I am using.

In this particular case I am trying to decide what signal path to take to create either rear fire sub situation or other tricks with use of delay to steer the subs.

I have either an FDS-355 Omnidrive or a newer FDS-336 processor at my disposal to do the delaying of of each driver.

Which would you do and a short why (I'm sure that I'm not considering something)?

I'm not using these subs with a meyer hi-mid system so I would have to phase align and I do know that the Meyer Processor incorporates 11.2 ms of delay on it's output.

A. Put the Meyer Processor in front of the delay processing to get the desired filter set that was intended. If you did this how would that 11.2 ms of delay on the processor effect the overall outcome of the sub arrangement, other than just adding that to the total delay.

B. Match the frequency response and curve at the front of the Omnidrive and do away with the meyer processor all together. You would do this knowing that the Meyer Processor wraps the phase (on the phase window of smaart) at a healthy 45 degree motion as the frequency range extends higher and those filter sets are not available in the Omnidrive. You would also loose the sense limiting (if that is important to you)

Harry Brill Jr.
December 5th, 2008, 03:37 AM
Hey Kip, What Meyer processor are you talking about? The only one I know with any latency is the Galileo. You also mention sense lines. If you take the output of a controller that uses sense lines into a DSP of any type (even an iTech amp for example) the sense limiting will no longer function correctly.

Either of your BSS processors should work if they will do the processing independantly. I'm pretty sure the 355 will work, but I have never used a 336.

Kip Conner
December 5th, 2008, 10:07 AM
Harry-
We are talking about an older piece. It's a Meyer B-2A processor that goes with the USW1 Passive Sub. When I ran an analysis of the unit to see if it was something that I could actually reproduce, I found that the Freq response curve was something very manageable. The Phase Response looked good as well, nice and consistent. On a whim I ran the delay locator (multiple times to be sure) and I got a delay of 11.2 ms. When I applied the delay to the measurement, the phase trace flipped and became "a leading trace" where before it was just a follower (like me!).

Arthur Skudra
December 5th, 2008, 02:47 PM
Based on my experience with both BSS processors, I think sonically the 355 is superior to the 336. Then again, that may not matter as much if it's just subs that you're going use the processor for.