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Old 8th February 2004, 05:19 PM   #21
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I see I read your graph wrong, but I'm still confused. Not your fault, I have dimensia today.

What do these graphs represent? Which one is "corrected" for meter errors? My answer is the one you add 35 Db to, the upper graph, correct?
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Old 8th February 2004, 05:26 PM   #22
Salas is offline Salas  Greece
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Default Bottom is the 'corrected'

As I explained with the pic post, the bottom one has the calibration file applied. The top one is as taken from the Radioshack. WinMLS corrects minus for whatever plus and vice versa. So the bottom one represents the top but with the correction imposed on it. Not sure for the absolute readings in the bass maybe I am +/1 2dB but sure that without subtracting substantial bass, the rough reading is way too full.
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Old 8th February 2004, 05:27 PM   #23
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*misstyped, ment +/- 1-2dB
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Old 8th February 2004, 05:37 PM   #24
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Have you considered doing the hardware soldering mod I have seen around? Have you ever used a 2nd method of calibrating to verify these corrections?

Your numbers if valid, make me question the consistency of the meter errors across the board. Your numbers are way off from the accepted norm, perhaps it is very "technique" sensitive as well.
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Old 8th February 2004, 07:16 PM   #25
Salas is offline Salas  Greece
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Default when followed the web....

Have tried other typical suggestions from the web.
In the folowing pic you will see what happened. Upper trace is a verified one from a lab. Plugged mine in the same room same speaker same set up. Bottom is what I got using such data. There is some good evidence that some Radioshacks are way bassheavy. They are definently happy in mid-high and dumb in the final octave. I hope there are many others outthere having experience to contribute with the Radioshack. Please do.
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Old 8th February 2004, 09:59 PM   #26
Salas is offline Salas  Greece
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Default RCA out

Keep in mind this is what I get from RCA out to soundcard MIC in not a correction for the neter readings.
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Old 9th February 2004, 09:37 AM   #27
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eric wallin-his site clearly showed to ADD ~6db ~ 20hz and 3db ~ 35hz... it under reads .


Perhaps deviation ? caused from what? Can your test methods be valid ? i dont know.
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Old 9th February 2004, 10:00 AM   #28
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Default phantom?

Maybe from the ~1VDC phantom of the pc cards mic inputs? I will run it through line and keep you posted. But as it stands (RCA out to MIC in) its sure it over reads.
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Old 9th February 2004, 04:56 PM   #29
Ron E is offline Ron E  United States
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You should go from RCA out to Line in.

The mic input is only for unpowered electret microphones with stereo 1/8" jacks. It has a 5V bias signal on the center conductor..
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Old 10th February 2004, 12:21 AM   #30
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Default Line, same stuff :-(

Went through line, got bass over readings again.
Here is the schematic of my RS:
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