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Old 03-24-07, 09:40 AM   #5 (Link)
 
brucek
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Re: IB makeover..........


Quote:
(could you show us the measurement?).
I have two BFD's. One 1100P and one 1124P.

I took a REW measure of two cables connected with an in-line short from 2Hz to 23KHz.

Then I removed the in-line short and inserted my 1100P with the signal passing through one channel (with the filters off). This eliminates all variables except the BFD response.
BFD set to -10dBV operating level.
Input level -10dB LED VU lit.

I'd say the response is pretty good. Only down a dB at 2Hz....

Here's two graphs.

The first graph is with a vertical scale of 45dB to 105dB as a reference showing the cable measure and the BFD response.

The second graph is the same with a much zoomed vertical scale to see small differences.

bfd response and cable loopback.jpg
ZOOMED IN.........
bfd response and cable loopback expand.jpg

So all that's standing between near DC response would be the processor. I'll bet my $6000 processor goes fairly low, but I've never measured it. If I had one of these LLT's, I would have be very careful. (I don't, I have a Servo-15.)

I suspect it's probably the source equipment and media that usually provides the protection. but, I think you have to be careful without a subsonic filter if you create one of these monsters.

brucek


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