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Discussion Starter #1 (Edited)
Random electronics measurements

I messed around with my PE17 the other day and took a bunch of FR measurements with different x-overs and different EQ settings. Overall it looks good. There is something going on with the HF response above 16.5khz, not sure what. Is my unit faulty? Throw me some ideas. The x-overs and EQ's were basically spot on with the way they are labeled. The biggest difference was EQ at 1khz which was actually measured as about 1.2khz.

This is the FR with the x-overs at the widest settings 10hz and 40khz. All EQ's bypassed and the input and output levels at the detents. Notice the low end filter at 10hz and the previously mentioned 16.5khz and up response.







20hz HP










80hz HP








250hz HP







3khz LP







10khz LP








This is all of the filters shown together.








I also took some EQ responses. These are at 10hz center and max +12db boost, while the cuts are max -15db. The 3 values are Q 2.0, Q 1.0 and Q 0.03. I figured this would be worst case scenario. There does appear to be some strangeness with the 0.03 cut and setting but there is interaction with the 10hz HP filter to consider.








Here is the exact same measurements but at a 1khz center, which better shows the results. Notice that the center is actually about 1.2khz.



 

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Discussion Starter #3
Thanks Bruce. I had thought that was the case, because it looked just like it, but I wasn't sure. I guess I must content myself with accurate measurement of gear(amps,recievers,eQ's) to 16.5khz. :sob:
 

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Awsome job Ricci! :clap:
 

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Discussion Starter #6
Or purchase a high end external soundcard................
Nah not now. I was joking. 16.5khz plenty good for me at-least until I figure out what I'm doing.:rofl2:

I think the PE-17 is a good EQ unit to consider for people using the big ported subs that need a HPF. It's not too expensive (about$170 on the Bay) it has a filter that can be adjusted down below 20hz the way to 10hz and it also has EQ capability below 20hz. The build quality is solid and it can also control the level matching between your reciever, or pre-pro and your pro-amp.
 

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Discussion Starter #7
My random electronics measurements

FR of my Outlaw 950 processor. Right channel pre-out. Looks goooood.:T except for the tiny amount of 60hz hum in there.













Here is the SW pre-out showing the various crossover settings which are spot on. 40, 60,80,100,120 and 150hz.















Here is the effect of the high pass filters on the right main channel. Not sure what's up with the response below 8hz but I'm not too concerned as it's 30db or more down and probably just some kind of measurement artifact. Xover points are 150,120,100,80,60 and 40hz.









 

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Discussion Starter #8
Now here we have a much cheaper piece of equipment. It's a Pioneer VSX517 reciever. I bought this guy after a bad storm wrecked havoc on a 8 or 9 year old Sony reciever I'd been using. Think I paid like $250 for it at BB. The SW response is a bit screwy. What is labeled as the xover frequency is not so. The xover choices are supposed to be 200, 150,100, 80 and 50hz. The actual crossover frequencies are more like 260,200,140,110 and 70:thumbsdown:. Atleast the low end response is good.









 

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except for the tiny amount of 60hz hum in there
Are you sure it's not from the soundcard? Do a straight cable loopback to check that.

Not sure what's up with the response below 8hz
Your signal is in the noise, so REW isn't getting valid signal to process. Actually looks like you may have the C-Weight compensation checked or a mic cal file still loaded - be sure that you have those cleared.

brucek
 

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I'll check to see whether I inadvertantly had the mic cal applied for the main channel HPF tests.

Would the tiny blip at 60hz be caused by the SC? I just figured since it is right at 60hz...
 

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Would the tiny blip at 60hz be caused by the SC? I just figured since it is right at 60hz...
Yep, and you can also see the harmonics of 60Hz at 120Hz and 180Hz. As I said, to find out if it's the soundcard, do a measure of the soundcard with a loopback cable only.

brucek
 
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