Think I could use help running my Crown XLS 1502's correctly

D

Danzilla31

Audioholic Spartan
Ok. Cleaning up cable runs and repositioning the Crowns or speakers may reduce other things... but it is pretty clear that you have a ground loop.

ATT, the cable box is acting as a path for ground loop. Disconnecting the coax isn't fully resolving the problem. Differences in electrical potential between circuits still exist.. it's just taking a less bothersome path when you disconnect the cable.

You probably need that coax hook up for TV, so permanent disconnection isn't likely to be an acceptable option.

Try changing the circuit your using to feed cable box. If that doesn't work, return the cable box power feed back to its original circuit and change your AVR feed. If that doesn't work, return the AVR back to its original feed and change the Crowns' circuit. Then try changing any two of the three devices circuits.

If that doesn't work, you might need an isolation transformer... likely for your Crowns, to break the loop.
Roger that I'll do work on my lawn know Lol get back with you after I keep tinkering and see what I can do to completely eliminate the loop.
 
GrimSurfer

GrimSurfer

Senior Audioholic
It could be cabling. If it is, a tidy up (as per a previous post) would help. But the goal here is to help you get your system to be silent when volume is at zero.

It's possible that you have a few problems (EMI/RFI and a ground loop). Your observations suggest that the ground loop is the big issue, so let's work to resolve that AFTER you get your cabling squared away.
 
D

Danzilla31

Audioholic Spartan
Ok. Cleaning up cable runs and repositioning the Crowns or speakers may reduce other things... but it is pretty clear that you have a ground loop.

ATT, the cable box is acting as a path for ground loop. Disconnecting the coax isn't fully resolving the problem. Differences in electrical potential between circuits still exist.. it's just taking a less bothersome path when you disconnect the cable.

You probably need that coax hook up for TV, so permanent disconnection isn't likely to be an acceptable option.

Try changing the circuit your using to feed cable box. If that doesn't work, return the cable box power feed back to its original circuit and change your AVR feed. If that doesn't work, return the AVR back to its original feed and change the Crowns' circuit. Then try changing any two of the three devices circuits.

If that doesn't work, you might need an isolation transformer... likely for your Crowns, to break the loop.
Thanks very much for all your help. All of you guys man you guys are the best

Ironically? I barely use cable at ALL. So I think it's time for cable to go. I can just stream what I want anyway. :D Tired of paying for something I never use
 
lovinthehd

lovinthehd

Audioholic Jedi
Thanks very much for all your help. All of you guys man you guys are the best

Ironically? I barely use cable at ALL. So I think it's time for cable to go. I can just stream what I want anyway. :D Tired of paying for something I never use
At my last place the cable guys, from an installation present when I moved in, had created a second ground...moved not long after so some cheater plugs did fine in the interim...I made sure not to touch the amp cases when wet n nekkid...
 
KEW

KEW

Audioholic Overlord
At my last place the cable guys, from an installation present when I moved in, had created a second ground...moved not long after so some cheater plugs did fine in the interim...I made sure not to touch the amp cases when wet n nekkid...
You, obviously, have a higher level of restraint than @Danzilla31 does!:p
 
D

Danzilla31

Audioholic Spartan
Ok guys here's the skinny I think the issue was on the right side of the wall.

When I took the cord off from the panamax power thing which I only use to plug sh@$!t that isn't amps or reciever into them and plugged both on the plug in to the far left.

Then plugged the AVR into the 20 amp circuit dedicated for the amps. Boom! No more noise period. I can stick my ear up to the speakers with the Crowns gains maxed out all day long and I can't hear diddley squat

Here's how it's played out know
2019-03-18 17.12.06.jpg
Far left plugin panamax's next to it inside left the SVS pb4000's

Far right
2019-03-18 17.14.17.jpg
Inside right other dedicated 20 amp circuit.
Outside right nothing is plugged in there no discernable noise period.

Final question that's just a cheap 15amp defiant power strip surge protector everything is plugged into just to fix the issue.

Should I get a better 20 amp power strip I'm worried that plugging all my amps and avr into that strip will affect dynamics or current

But I don't know enough yet to know if this is relevant is this a big deal or am I worried about something that is a non issue? Please advise guys and thanks again for everything
 
D

Danzilla31

Audioholic Spartan
Fudge man thank the Lord SVS makes some sturdy speakers I've ran these things hard on that ground loop for Indont know how long and they are still working just fine.

I actually have done quiet a few things wrong in this journey and still haven't managed to blow anything up on them!

They're built like tanks
 
GrimSurfer

GrimSurfer

Senior Audioholic
Ok guys here's the skinny I think the issue was on the right side of the wall.

When I took the cord off from the panamax power thing which I only use to plug sh@$!t that isn't amps or reciever into them and plugged both on the plug in to the far left.

Then plugged the AVR into the 20 amp circuit dedicated for the amps. Boom! No more noise period. I can stick my ear up to the speakers with the Crowns gains maxed out all day long and I can't hear diddley squat

Here's how it's played out know
View attachment 28735
Far left plugin panamax's next to it inside left the SVS pb4000's

Far right
View attachment 28736
Inside right other dedicated 20 amp circuit.
Outside right nothing is plugged in there no discernable noise period.

Final question that's just a cheap 15amp defiant power strip surge protector everything is plugged into just to fix the issue.

Should I get a better 20 amp power strip I'm worried that plugging all my amps and avr into that strip will affect dynamics or current

But I don't know enough yet to know if this is relevant is this a big deal or am I worried about something that is a non issue? Please advise guys and thanks again for everything
It depends on how much your total draw is on that circuit. Add up the amps for all connected devices. If it's more than 13A, then get a 20A power bar. I'd recommend Furman or Tripp Lite metal bodied ones.
 
GrimSurfer

GrimSurfer

Senior Audioholic
Fudge man thank the Lord SVS makes some sturdy speakers I've ran these things hard on that ground loop for Indont know how long and they are still working just fine.

I actually have done quiet a few things wrong in this journey and still haven't managed to blow anything up on them!

They're built like tanks
No biggie. A 60 Hz hum isn't going to fry a speaker, as long as the amp doesn't clip or you're seriously cranking things up.
 
GrimSurfer

GrimSurfer

Senior Audioholic
I'm really happy to hear that the problem is resolved, Dan... probably better than you imagined it could be if there's no hum or hiss whatsoever.

Now enjoy the sound, once the lawn is done!:p
 
D

Danzilla31

Audioholic Spartan
I'm really happy to hear that the problem is resolved, Dan... probably better than you imagined it could be if there's no hum or hiss whatsoever.

Now enjoy the sound, once the lawn is done!:p
Oh you better believe I will! :D
 
D

Danzilla31

Audioholic Spartan
Thank you everyone for all the help today figuring this out. You guys are the best!
 
highfigh

highfigh

Seriously, I have no life.
I understood that, just questioning whether the Crown might be as safe as an AVR without the ground - which might be the case if they only added the ground because of the more dangerous "on-the-road" treatment that pro gear sees.
GrimSurfer is pretty convinced that there are fundamental differences in the design of the pro amp that require the ground to maintain safety in the home environment. I am inclined to believe him.
From the link,

http://www.codebookcity.com/codearticles/nec/necarticle640.htm

"Do not ground metal equipment racks and enclosures, even though 640.22 says to do this. As in many other NEC requirements, the meaning here is "bond." Grounding these provides absolutely no benefit, but may introduce problems. You want to bond them, so you eliminate differences of potential. See the Article 100 definitions of grounding and bonding. Refer to Article 250 Part V for bonding requirements in general."

Consumer systems aren't usually bonded- that's the difference between pro and consumer equipment. A pro system requires bonding everything, which also means ground loops are moot. The fact that bonding is required, doesn't mean it happens, though.

http://www.codebookcity.com/codearticles/nec/necarticle100.htm
 
GrimSurfer

GrimSurfer

Senior Audioholic
From the link,

http://www.codebookcity.com/codearticles/nec/necarticle640.htm

"Do not ground metal equipment racks and enclosures, even though 640.22 says to do this. As in many other NEC requirements, the meaning here is "bond." Grounding these provides absolutely no benefit, but may introduce problems. You want to bond them, so you eliminate differences of potential. See the Article 100 definitions of grounding and bonding. Refer to Article 250 Part V for bonding requirements in general."

Consumer systems aren't usually bonded- that's the difference between pro and consumer equipment. A pro system requires bonding everything, which also means ground loops are moot. The fact that bonding is required, doesn't mean it happens, though.

http://www.codebookcity.com/codearticles/nec/necarticle100.htm
Bonding can give electrons a place to go, other than through an amp circuit, as it follows a ground loop. There are times, however, when it can create a ground loop. It all depends ton the configuration of the gear.

The best way to avoid ground loops is to place everything on the same power circuit. I see this as one of the reasons to upgrade to a 20A line, not to prevent current sagging from a 15A line when the gear draws less than 13A current (2A buffer to avoid tripping circuits during in rush if everything is being powered up at the same time).
 
GrimSurfer

GrimSurfer

Senior Audioholic
For those tuning in late, bonding grounded and double grounded gear together is usually a big no-no.

Electrons flowing from an internal fault in grounded gear could find an easier path to ground thru the bonding strap connected to the double insulated gear (such as might happen if the socket was wired incorrectly... neutral and ground reversed). The chassis or case of the double insulated gear will then be energized.
 
highfigh

highfigh

Seriously, I have no life.
Bonding can give electrons a place to go, other than through an amp circuit, as it follows a ground loop. There are times, however, when it can create a ground loop. It all depends ton the configuration of the gear.

The best way to avoid ground loops is to place everything on the same power circuit. I see this as one of the reasons to upgrade to a 20A line, not to prevent current sagging from a 15A line when the gear draws less than 13A current (2A buffer to avoid tripping circuits during in rush if everything is being powered up at the same time).
Bonding is supposed to create a situation where the equipment is equipotential, which means ground loops can't happen. It can all be on the same circuit and still have ground loops because the receptacles aren't necessarily in one location. That eliminates power phase issues, but won't always do away with ground loops- I did an installation where the electrician DIDN'T do what I asked, although the cabinet where the equipment lives is on one circuit. The AV preamp and power amp were both made by Krell and have grounded power cords, but with XLR cables, it hummed pretty badly and that definitely was unacceptable. As soon as I switched to unbalanced cables, it was quiet.

This thread is about pro gear and comments about grounding were made, but pro gear, again, is supposed to be 'bonded' and that's not something most consumers have ever heard about.
 
highfigh

highfigh

Seriously, I have no life.
For those tuning in late, bonding grounded and double grounded gear together is usually a big no-no.

Electrons flowing from an internal fault in grounded gear could find an easier path to ground thru the bonding strap connected to the double insulated gear (such as might happen if the socket was wired incorrectly... neutral and ground reversed). The chassis or case of the double insulated gear will then be energized.
And if the breaker or receptacle is GFCI, it will open. This can also cause a non-GFCI to open. If this doesn't cause power interruption, it can show up in some other way, like loud snapping sounds, smoke, etc.
 
GrimSurfer

GrimSurfer

Senior Audioholic
Bonding is supposed to create a situation where the equipment is equipotential, which means ground loops can't happen. It can all be on the same circuit and still have ground loops because the receptacles aren't necessarily in one location. That eliminates power phase issues, but won't always do away with ground loops- I did an installation where the electrician DIDN'T do what I asked, although the cabinet where the equipment lives is on one circuit. The AV preamp and power amp were both made by Krell and have grounded power cords, but with XLR cables, it hummed pretty badly and that definitely was unacceptable. As soon as I switched to unbalanced cables, it was quiet.

This thread is about pro gear and comments about grounding were made, but pro gear, again, is supposed to be 'bonded' and that's not something most consumers have ever heard about.
Sure. But this thread also involves mixing pro and consumer gear, which are often configured differently.

As an aside, I wish the industry would adopt a name other than "pro". It suggests a qualitative difference, which is wrong. The difference is in the application, with pro gear designed for a set of specific uses.

Much in the same way that a Checker taxi isn't necessarily better than a car somebody can buy from a dealer. A Checker was a very robust cab, but wouldn't have passed even the most basic of noise, vibration, harshness tests... not to mention acceleration, fuel economy etc... of commercially available passenger cars.
 
Last edited:
GrimSurfer

GrimSurfer

Senior Audioholic
And if the breaker or receptacle is GFCI, it will open. This can also cause a non-GFCI to open. If this doesn't cause power interruption, it can show up in some other way, like loud snapping sounds, smoke, etc.
True, but a miswired GFCI is nothing more than an expensive socket. And they can be, electrically speaking, noisy. That's why I'd rather have my audio equipment wired correctly and passing through a fused surge protector instead of through a GFCI.

(How many people have gone around their homes with a plug-in circuit checker? Not many, I suspect. When I went around my home, I found six miswired sockets and two GFCIs that were wired in series (which isn't dangerous but is a pure waste of money and an unnecessary complexity which offers no additional protection whatsoever).)

The other issue is the grounded-to-double insulated problem (via strapping or even an unbalanced cable). If the chassis/case for a double insulated device is energized, it may not loop back to ground. Why? Because it is electrically isolated from the "mains", to use a concise and appropriate British term.

It WILL try to find the best ground, if somebody touches it... in which case they'd be part of a ground loop that, until that exact moment in time, didn't exist. (A ground loop occurs when electrons find ground through an alternate path. It is in no way restricted to instances where this creates noise, although this is how most audio folks use it.)

Now this doesn't happen frequently because things are engineered almost to the point of being idiot proof... unless the idiot in question is holding onto a hot water radiator with one hand and touching poorly configured gear with another. But accidents do happen... not necessarily through idiocy but through a series of relatively innocuous events that end in tragedy. A great example comes to mind, but that's another story for another day...
 
Last edited:
newsletter

  • RBHsound.com
  • BlueJeansCable.com
  • SVS Sound Subwoofers
  • Experience the Martin Logan Montis
Top