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Post by foggy1956 on Jul 30, 2017 15:59:16 GMT -5
Best I can tell, everything is going to schitt below 40hz
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Post by knucklehead on Jul 30, 2017 16:22:52 GMT -5
Why oh why do people hit "quote" on such a long post?!?!? We've seen it already!
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Post by foggy1956 on Jul 30, 2017 17:18:51 GMT -5
Pics of my subs in REW for comparison, room definitely needs added tratments   |
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Post by Boomzilla on Jul 30, 2017 17:35:21 GMT -5
These graphs are of the Pendragons alone (no sub) with the various positions of the USP-1 preamplifier's high-pass filter. The microphone was one meter from the center of the speaker's tweeter array center tweeter.  |
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Post by Boomzilla on Jul 30, 2017 19:01:59 GMT -5
these graphs are terrible...use REW REW can KMA. |
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Post by musicfan on Jul 30, 2017 19:12:55 GMT -5
these graphs are terrible...use REW REW can KMA. hahahaahh |
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Post by mfeust on Jul 31, 2017 16:03:07 GMT -5
Why oh why do people hit "quote" on such a long post?!?!? We've seen it already! To PISS you off.  Mark |
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klinemj
Emo VIPs 
Official Emofest Scribe
Posts: 15,095
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Post by klinemj on Jul 31, 2017 20:00:17 GMT -5
I still see no graphs...have you considered just uploading using the "add attachments" option?
Mark
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Post by Boomzilla on Jul 31, 2017 20:08:27 GMT -5
How strange, Mark - The other posters say they see the graphics...
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Post by Gary Cook on Jul 31, 2017 21:48:44 GMT -5
I can see them on my MacMini at home but not on my PC at work or on my iPad or iPhone. My guess is the Mac, being mine, automatically logs into Google Drive but the PC at work isn't and doesn't.
Cheers
Gary
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Post by Boomzilla on Aug 1, 2017 5:27:05 GMT -5
Thank you, Gary - I've listed the links now from the excellent postimage.org site recommended by RichGuy. Can everyone see them now? Thanks - Boomzilla |
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klinemj
Emo VIPs
Official Emofest Scribe
Posts: 15,095
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Post by klinemj on Aug 1, 2017 6:40:33 GMT -5
Now I see them! And, you are right...it's not a linear thing. Someone else noted that a while back. Pretty sure the XSP-1 has the same approach.
Mark
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Post by milsap195 on Aug 1, 2017 6:56:42 GMT -5
So what frequency does each dot correspond to?
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Post by Boomzilla on Aug 1, 2017 10:35:29 GMT -5
LOL - THAT's harder to calculate. If I had completely flat speakers, (or a loopback cable) it would be easier to detect.
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Post by Gary Cook on Aug 1, 2017 19:56:23 GMT -5
Because of the speaker dips around 100 hz and 50 hz plus the flare around 70 hz it's hard to make much sense of the raw data. Which roughly looks a bit like this; Click -3db -12db1 - 30 2 - 32 3 - 33 4 120 30 5 125 50 6 150 55 7 180 60 8 200 80 9 225 100 10 250 100 Personally with those spreakers I like the look of click 10, it negates most of the flare at 70 hz and smooths the dips at 50 and 100 hz. Then I'd aim for the cross over to the sub woofer at around 100 hz as it's such an important frequency in music. A dip at 100 hz has a horrible effect on music, it's right in the meat of the drums (kick, tympani and toms) hard on a tuba, double bass and cello and murder on a trombone and bass guitar. OMG bass guitar, I hate to even contemplate -10db down on Roger Waters bass riff on Money, or John Deacon on Another One Bites the Dust, Herbie Flowers magic for Walk on the Wild Side. It's heresy to even imagine it.  Speaking of which, I have tickets;  Cheers Gary |
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Post by Boomzilla on Aug 2, 2017 6:58:32 GMT -5
Hi Gary Cook - Good suggestions, you! However, there's another factor that complicates things. Although the USP-1 has crossovers that have a (stated) range of 50-250 Hz., the subwoofer's plate amp ALSO has a crossover pot with a (stated) range of 40-150 Hz. The sub's crossover is not defeatable. This means that no matter how high I set the preamp's crossover, the sub won't be going above 150 Hz. due to its own crossover. The normal recommendation is to set the sub's plate amp crossover as high as possible and then use the upstream bass management to affect whatever crossover frequency is desired. So with my USP-1's crossover already set to seven clicks (180 Hz. per your estimate), I'm already exceeding the sub's internal crossover capacity. This means that at about 150 to 180 Hz, the sub is rolling off at the USP-1's slope PLUS the plate amp's slope. Assuming that the USP-1 is roughly 6 dB / octave and the plate amp is 12 dB / octave, the combination means that the sub rolls off at 18 dB / octave. This should work fine with the 6 dB / octave slope of the high pass filter. But I will try your suggestion to try the 10 settings to see how they sound. Thanks again - Boom |
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Post by Gary Cook on Aug 2, 2017 16:12:38 GMT -5
It would probably pay off to test the sub woofer's cross over in the same fashion. At the very least it will tell you whether the dips at 50hz and 100hz and the flare at 70hz are speakers or (more likely) room. If they are room driven it's going to be tricky to overcome with cross over settings, because the sub will suffer at the same frequencies. If it's the speakers then crossing over highest possible will probably yield the best result. Good fun to be had.
Cheers
Gary
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Post by foggy1956 on Aug 2, 2017 21:36:38 GMT -5
It would probably pay off to test the sub woofer's cross over in the same fashion. At the very least it will tell you whether the dips at 50hz and 100hz and the flare at 70hz are speakers or (more likely) room. If they are room driven it's going to be tricky to overcome with cross over settings, because the sub will suffer at the same frequencies. If it's the speakers then crossing over highest possible will probably yield the best result. Good fun to be had. Cheers Gary If I remember I believe his measurements were taken at 1 meter or less which should negate most room nodes |
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Post by Boomzilla on Aug 4, 2017 1:31:35 GMT -5
Not only was the microphone but one meter from the front of the speakers / sub, but also the one-second sweep time means that any part of the frequency spectrum was active for significantly less than a second. In other words, the sweep begins at 20 Hz. and one second later has risen to 20 KHz. - ending there. This would reduce room interference, and the sweep-duration is user configurable. Further, each curve (in the set I displayed) is a combination of two sequential sweeps to minimize random / external noises. This is also user configurable - the noisier the environment, the more one should up the sweep-count.
Overall, I'm fairly happy with the Fuzzmeasure software. It may not have the full flexibility of REW, but the learning curve is not as steep.
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