[lexx2004]

I have read many forums where individuals seem confident that they've calibrated their sub to say, for example, exactly 82db (to compensate for the RS meter's inherent inaccuracy when calibrating all channels to 85db) . I'd like some feedback to determine how to get an exact sub calibration. I have both the analog RS meter and the Galaxy CM140 meter. I've been using the AVIA test disc warble tone which works in conjunction with another speaker, say center channel and sub, or left speaker and sub. I usually calibrate using the center channel and the sub. From what I've read, the warble tone is a wide band test signal so my room likely has some peaks and dips which is causing the meter to fluctuate. My room is acoustically treated with more than enough bass traps and HF panels but I still cannot get a precise calibration as so many individuals claim to have gotten. Are these individuals using the "average" as indicated on the meter and then claiming to have dialed in their sub to that exact db? That's the only explanation I come up with. Maybe someone could suggest a different test signal for subwoofer calibration. I've also tried the THX test signals which is present on a few DVD movies but I get different readings using that method versus the AVIA for not only the sub but all the other channels as well. Any advice would be appreciated. :wits-end:

 

[lexx2004]

How is it that you are certain about that?

Regards,
Wayne

I guess I should have been more specific. I have HF panels at all 1st and secondary reflection points (11 in total). I have a single bass trap in each corner (8 in total as some are also used throughout the room). Visually, the room looks "full" of panels and traps (the room is 15x20 feet). I'm lucky that my girlfriend is very understanding in this regard. Certainly I could add more traps (eg. at all tri-corners, ceiling bi-corners etc. but that would have a far more detrimental impact on room aesthetics since I do not have a dedicated room. So, Wayne, thanks, I should have quantified what I meant by "more than enough treatment". I find that most enthusiasts prefer to EQ than to treat the room but I prefer the latter. Some would argue that it's best to do both but I prefer not to go the EQ route at all.

 

[lexx2004]

hehe, and Wayne should have been more clear in his post also. What he was saying (I assume, since it was the same question in my head), was how do you know how effective (or not) your efforts have been when you haven't taken a response measurement or waterfall plot of your room with a program such as REW?

brucek

I should have mentioned that I did take measurements before and after treatment. The room was very "bright" prior to treatment. I did a 1/6 octave test and noticed a significant difference before and after the tests (in terms of leveling out peaks and dips). I haven't used REW as yet or tested every hz from say 20 hz to 80 hz using test signals so there are bound to be peaks and dips in there regardless of how much treatment I do. You can only do so much when you don't have a dedicated room.