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Post by Johnkenn on Aug 1, 2014 21:36:19 GMT -6
Or am I just insane? I seem to be having some headroom issues...or saturation or something...All mogamis, but it's a $99 DBX PB48. You know how it is, though. Once you think you hear something, then you can't get it out of your mind...
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ericn
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Post by ericn on Aug 1, 2014 21:41:59 GMT -6
Your using one of those cheap made in China 48 point TRS modular bays if I am correct John?
Then not only yes , but hell yes!
Pull a module look at the cheap jacks compared to a real bay like a ADC TT!
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Post by Johnkenn on Aug 1, 2014 21:43:52 GMT -6
Damnit...
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Post by tonycamphd on Aug 1, 2014 21:47:38 GMT -6
bypass the patchbay and see if it does the same thing? Then you can say "damn it!", but not before lol
also before you panic, make sure your polarity wiring is right on your cables?
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Post by Johnkenn on Aug 1, 2014 21:50:17 GMT -6
Can you suggest a ready made one? De-normalled?
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Post by Johnkenn on Aug 1, 2014 21:50:56 GMT -6
bypass the patchbay and see if it does the same thing? Then you can say "damn it!", but not before lol also before you panic, make sure your polarity wiring is right on your cables? Damnit, Jim...I'm a singer, not a scientist... |
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Post by tonycamphd on Aug 1, 2014 21:55:30 GMT -6
bypass the patchbay and see if it does the same thing? Then you can say "damn it!", but not before lol also before you panic, make sure your polarity wiring is right on your cables? Damnit, Jim...I'm a singer, not a scientist... well i know you know how to put one piece after another with patch cords, so i'm assuming you mean wiring polarity? Make sure the wires behind the end barrels on the 1/4" cables are the same color in both spots, at both ends. |
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Post by Guitar on Aug 1, 2014 21:56:37 GMT -6
I am thinking, "probably not." I know that psychoacoustics can at times get, well...psycho. From experience, of course.
The technical backup to this statement would be, with balanced low impedance signals, an "acceptable" cable run is usually considered to be hundreds of feet. I am sure your patchbay, cables, snakes and whatnot are well under that in a small room.
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Post by Johnkenn on Aug 1, 2014 21:57:06 GMT -6
Damnit, Jim...I'm a singer, not a scientist... well i know you know how to put one piece after another with patch cords, so i'm assuming you mean wiring polarity? Make sure the wires behind the end barrels on the 1/4" cables are the same color in both spots, at both ends. Does Mogami screw that up sometimes or something? |
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Post by Johnkenn on Aug 1, 2014 21:57:54 GMT -6
I am thinking, "probably not." I know that psychoacoustics can at times get, well...psycho. From experience, of course. I think I'm suffering from it... |
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Post by tonycamphd on Aug 1, 2014 21:58:26 GMT -6
well i know you know how to put one piece after another with patch cords, so i'm assuming you mean wiring polarity? Make sure the wires behind the end barrels on the 1/4" cables are the same color in both spots, at both ends. Does Mogami screw that up sometimes or something? not likely, but you never know? it's an easy check. |
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Post by Johnkenn on Aug 1, 2014 22:06:28 GMT -6
Now I'm paranoid about my patchbay...
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Post by Johnkenn on Aug 1, 2014 22:06:50 GMT -6
I'm not paranoid...
Why, have you guys heard something?
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ericn
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Post by ericn on Aug 1, 2014 22:08:06 GMT -6
Cheap bays use jacks that are designed for being in gear and not patched and un patched all the time!
Bypass if you see a difference buy a real bay !
Cheap bays make great vent panels!
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Post by tonycamphd on Aug 1, 2014 22:11:20 GMT -6
Cheap bays use jacks that are designed for being in gear and not patched and un patched all the time! Bypass if you see a difference buy a real bay ! Cheap bays make great vent panels! yes Johnkenn listen to this man.. |
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ericn
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Balance Engineer
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Post by ericn on Aug 1, 2014 22:16:11 GMT -6
Tony, best use of a cheap bay ever, template for drilling holes on blank panels for punching
DB25 panels!
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Post by gouge on Aug 1, 2014 22:16:28 GMT -6
have you tried using the pad on your preamp?
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Post by Johnkenn on Aug 1, 2014 22:16:40 GMT -6
I'm gonna...
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Post by tonycamphd on Aug 1, 2014 22:19:31 GMT -6
have you tried using the pad on your preamp? I'm probably going to feel like an idiot for asking this..., but here goes 8/ why? edit; jeez, never mind i read the lead post again, i'm going to bed lol |
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Post by svart on Aug 1, 2014 22:27:01 GMT -6
Physics says that passive objects cannot have headroom issues..
So the EE answer is no, your patchbay is not limiting your headroom.
However..
It can have insertion loss though, but that's not going to limit headroom, and we are talking fractions of a dB..
They can also have crosstalk issues, or frequency response issues, but these would be rare and obvious if they were happening.
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Post by tonycamphd on Aug 1, 2014 22:30:34 GMT -6
Physics says that passive objects cannot have headroom issues.. So the EE answer is no, your patchbay is not limiting your headroom. However.. It can have insertion loss though, but that's not going to limit headroom, and we are talking fractions of a dB.. They can also have crosstalk issues, or frequency response issues, but these would be rare and obvious if they were happening. we are talking about the use of the patchbay as a system here, wiring included, I know you're the expert, but it sounds like your saying sending my speaker outs from my adcom through 26 gauge wire i use for capsule hookups will work because there is no headroom issue? the physics i'm familiar with are saying "howz that?" things wired out of phase can wreak havoc as well. |
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Deleted
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Post by Deleted on Aug 1, 2014 23:12:55 GMT -6
until you test, relax.
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Post by LesC on Aug 2, 2014 0:29:47 GMT -6
I was using four cheap patch bays like John is using for a long time. Over the last couple of years, I traced several problems with channel balancing, distortion, and various other issues to the crappy patch bays. I've recently done more hard-wiring, getting rid of patching that I rarely used. And I got a slightly more expensive Sampson S-Patch Plus, so far I'm happy.
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Post by gouge on Aug 2, 2014 0:33:20 GMT -6
I've got a rack full of the s-patch plus as well and I think they are really solid.
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Post by svart on Aug 2, 2014 8:30:24 GMT -6
Physics says that passive objects cannot have headroom issues.. So the EE answer is no, your patchbay is not limiting your headroom. However.. It can have insertion loss though, but that's not going to limit headroom, and we are talking fractions of a dB.. They can also have crosstalk issues, or frequency response issues, but these would be rare and obvious if they were happening. we are talking about the use of the patchbay as a system here, wiring included, I know you're the expert, but it sounds like your saying sending my speaker outs from my adcom through 26 gauge wire i use for capsule hookups will work because there is no headroom issue? the physics i'm familiar with are saying "howz that?" things wired out of phase can wreak havoc as well. True, but he asked if his "patchbay" could be causing "headroom" issues IIRC. The electrical definition of "headroom" is the amount of signal level increase before clipping(or "running out of voltage due to current limitation"). In the case of lost headroom, that means the signal peaks are being reduced (clipped most likely, which would distort heavily) while the noise floor stays the same, I.E., your DR (dynamic range) is reduced. Since patchbays are passive devices, it's impossible for it to reduce DR, but it IS possible to attenuate a whole signal while preserving DR through straight loss. This doesn't say anything about distortions that can be caused by various sources like diode junctions created by corroded connectors, crosstalk from poor routing inside the patchbay, etc. If Johnny K has the patchbay I think he has, then he has TRS on both sides, right? So the internals would look like this:  So, it's as simple as the connectors and a small PCB inside, no active components to limit current and therefor nothing to reduce headroom specifically. |
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