Help with X-mas decision!ICBM or ETF mich & software? (1 Viewer)

[Steve Morgan]

I have a choice since both are about the same cost. I have a RP91 and have yet to hook up the DVD-A.This is where the Outlaw ICBM would come in to play, on the other hand I just purcased an BFD EQ to try to tame the peaks with my 2 subs.The subs are different, a SVS 20-39cs and a Paradigm Servo 15a.I have the RS spl meter which EFT says will work but not as accurate as their mich and amp.What to do? Help me with my decision.

 

[BruceD]

The biggest improvement to the sound in my listening room came from judicious use of ETF and a BFD on my sub to smooth out main speaker location, xover to sub optimization, dialing in BFD filters to cut peaks, and optimizing main, center, and surround speaker distances (delay).

My vote is ETF, and you can use the correction values for the RS SPL meter. Put the SPL meter on a tripod at ear height.

BruceD

 

[Guy Kuo]

Bruce and I both really like the ETF program. Without such a tool, getting your speakers optimally positioned is debatably an exercise in faith over matter. The ETF program lets you actually see what those speaker postion and orientation changes are actually doing to YOUR in room response. You can sometimes get good results using rules of thumb for positioning or by using a room modeling program, but nothing beats actually measuring the effect of each move for rapidly getting you to verifiably better placement.

Basically, you'll use the program for checking both your main speaker and subwoofer performance. The "demo room" example on the ETF site outlines how one might use the program to measure and compare speaker response at multiple locations. Believe me, it is a far cry above scooting a speaker, going back to your listening position and convincing yourself if it sounds better or not compared to the previous position. Not too many of us have that sort of acoustic memory. With the ETF program, you put a grid of tape on the floor to mark speaker trial positions and then measure the response at each location very quickly. Once that is done, you overlay the resultant response curves to compare the various positions. It is very effective.

For those who are equalizing their subs, having the ability to see a graph of subwoofer bass response in near real time (repeated every two or three seconds) makes dialing in the filters quick child's play. In three seconds, the program gathers and plots all the acoustical measurements that would take you fifteen minutes or more to do manually with less accuracy and resolution.

Add on top of that an entire suite of measurements like impulse response, phase response, and RT60 measurement. You basically get a tool which gives you information about your room which is impossible to get without such a program. It isn't cheap, but ask yourself if doubling the smoothness of your speaker frequency response is worth the cost. I think the answer is yes if you have a mid-fi or better system.

On the other hand, a tool like ETF gives you more information about how your system is actually working. Sometimes ignorance is bliss - like the pre AVIA days when you didn't get the accursed red filter that suddenly made everyone able to see how much red push was in their display. ETF might point out some room and equipment problems you didn't realize exist.