Discrepancies between JBL pdf file vs. dwp files for SRX 725
timeslip
Posts: 7
Looking at the SRX700 zip file, downloaded from the following link:
http://www.jblpro.com/catalog/general/t ... D=18&Run=1
I noticed some discrepancies between the Driverack 260 pdf file and the dwp files. For example, for my SRX 725 bi-amped w/ 718S subs, the Q value for the parametric "EQ1" on the highs, centered at 1.62 KHz is Q=3 in the pdf, but the dwp file "SRX725BSUB.dwp" has Q=0.175. The Q=0.175 also comes up in the DBX hardware processor's setup wizard. Furthermore, the file "SRX725B.dwp" which is the same bi-amped top cabinet, has Q=5.016. Of the three Q values (5.016, 3, and 0.175), which one is correct?
http://www.jblpro.com/catalog/general/t ... D=18&Run=1
I noticed some discrepancies between the Driverack 260 pdf file and the dwp files. For example, for my SRX 725 bi-amped w/ 718S subs, the Q value for the parametric "EQ1" on the highs, centered at 1.62 KHz is Q=3 in the pdf, but the dwp file "SRX725BSUB.dwp" has Q=0.175. The Q=0.175 also comes up in the DBX hardware processor's setup wizard. Furthermore, the file "SRX725B.dwp" which is the same bi-amped top cabinet, has Q=5.016. Of the three Q values (5.016, 3, and 0.175), which one is correct?
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After unzipping the file called "SRX700tunings", the folder called "SRX 700 dbx Drive Rack 260" has a pdf file is called "Tunings For SRX700 for dbx Drive Rack 260" as well as the corresponding dwp files. It's all referring to the same processor, Driverack 260, but the values in the pdf file differ from some of the corresponding dwp files. Furthermore, two dwp files for the same top cabinet, SRX 725, with and without sub, have radically different Q values for the high EQ. It seems strange to me to have such different Q values for the high EQ, especially when the corresponding pdf file for the same processor has yet another value. I'm just wondering if there's a typo somewhere, and if so, which one is the typo.
All of the different files are probably developed by different humans who have different tastes. All of the basics like xo points will be very similar but filter selection, alignment and EQing will vary with the person doing the measurement. All of the files are correct but different. The various Q values are being used to best accomplish a flat response and there are several ways to skin a cat.
I agree about tastes and several ways to accomplish a flat response. Nevertheless, in the 3 cases, the other parameters are the same: same high shelf, same mid eq. Even the center frequency of 1.62 KHz on the filter I'm questioning is the same. The only difference in all 3 cases is how wide or narrow that filter is. Certainly taste would affect the choice of Q, but I would think if the goal is flatness, with all other parameters being equal, one of the Q's would be more correct than the others - especially when it's as radical as 0.175 vs. 5.016. I don't have the equipment to measure for flatness, hence I looked to the factory settings as a starting point. I can certainly hear a major difference between the two, and each has it's pros & cons wrt taste, but I was just wondering which might be more flat according to the professionals who I assume had the resources to measure for flatness, or if by any chance it could be a typo.
#1: Which has more gain before feedback with no GEQ help.
#2: Which has more GBF which GEQ adjustments (not causing unnatural sound).
#3: Which sounds more pleasing playing pre-recorded music.
Something else you may be overlooking. Those files may have been done in different chambers all having different RT, and maybe different size chambers. Maybe just a pretty dead room, but good acoustics (whatever that means). Maybe one is which Smarrt, one is done by a simple 31 band spl analyzer, and one by the man with the golden ear.
Maybe you should set up all three as a preset, then trial all 3 in each room you play. What ever sounds the best is the one to tweak with the Pre-PEQ or pre-GEQ.
DRA