Marantz av20 audessey x setup tuning problems

[TLS Guy]

Pics. Sorry its mess right now. Been trying diferent wires and need to clean it back up once I fix this.

You are falling into a common trap, of adding and adding grounds, that seldom solves the problem.

You now have a complex system, and to make this work and have a silent background, then you have to design a ground plane and that takes skill and expereince.

It is clear to me that plate amp ground is not at the same potential as the rest of your system. That is caused by a resistance to ground between the receptacle the plate amp is plugged into and the rest of the system. So you best bet is to power that plate amp from a cable going back to your main system.

The more complex the system, the more likely you are to run into ground loops.

One approach might be to lift the ground in the xlr plug at the plate amp connection.

You usually solve these problems by removing grounds and not adding them paradoxically.

 

[ssmokeyy]

You are falling into a common trap, of adding and adding grounds, that seldom solves the problem.

You now have a complex system, and to make this work and have a silent background, then you have to design a ground plane and that takes skill and expereince.

It is clear to me that plate amp ground is not at the same potential as the rest of your system. That is caused by a resistance to ground between the receptacle the plate amp is plugged into and the rest of the system. So you best bet is to power that plate amp from a cable going back to your main system.

The more complex the system, the more likely you are to run into ground loops.

One approach might be to lift the ground in the xlr plug at the plate amp connection.

You usually solve these problems by removing grounds and not adding them paradoxically.

I did try changing the outlet the plate amp is plugged into. Still had the noise. I could try to plug it into the apc conditioner but my fear is that it wont be able to pass the amps needed to drive the amp fully.

Im trying to get what u mean by the resistance to ground between the receptacle and the system. Like meaning it could be loose or bad quality outlet. Every outlet is heavy duty or ps audio 20 amp model. But again I have tried changing the outlet the plate amp is plugged into and still has the noise but the other plate amp does not has noise.

I have been looking into xlr ground lift devices. Not sure what model is a quality part. Never had to use one or sell one before. Do u have any u recommended?

 

[TLS Guy]

I did try changing the outlet the plate amp is plugged into. Still had the noise. I could try to plug it into the apc conditioner but my fear is that it wont be able to pass the amps needed to drive the amp fully.

Im trying to get what u mean by the resistance to ground between the receptacle and the system. Like meaning it could be loose or bad quality outlet. Every outlet is heavy duty or ps audio 20 amp model. But again I have tried changing the outlet the plate amp is plugged into and still has the noise but the other plate amp does not has noise.

I have been looking into xlr ground lift devices. Not sure what model is a quality part. Never had to use one or sell one before. Do u have any u recommended?

You never plug power amps into conditioners. Those are for the fragile low power circuits.

No, I don't because I generally make my own cables.

This one is available from B & H photo that are a good outfit. That is what to try next.

 

[ssmokeyy]

Integra was a 2 prong av20 is a 2 prong.

 

[TLS Guy]

Integra was a 2 prong av20 is a 2 prong.

It looks as if that plate amp is three prong. If that is the case, then I can be certain, that XLR ground break will take care of your noise problem.

 

[ssmokeyy]

So i installed a cheater 3 to 2 prong adapter. noise is gone. But I don't want to lose the ground. I also ordered the xlr part. But I have found that if I plug the av20 and plate amp in the same outlet the loop is gone.

 

[TLS Guy]

So i installed a cheater 3 to 2 prong adapter. noise is gone. But I don't want to lose the ground. I also ordered the xlr part. But I have found that if I plug the av20 and plate amp in the same outlet the loop is gone.

Then you have proved what I was telling you, that ground loops are caused by grounds at a different potential.

 

[ssmokeyy]

U were correct. I wasn't saying u were wrong. Just sucks that the ground wire from the av20 to the plate didnt work. So now I need to change some thing and find a good power conditioner/ high out part that can run both items.

 

[TLS Guy]

U were correct. I wasn't saying u were wrong. Just sucks that the ground wire from the av20 to the plate didnt work. So now I need to change some thing and find a good power conditioner/ high out part that can run both items.

I don't know what you are up to. Power amps do not need, and should not be connected, to any sort of power conditioner. The power supplies of decent power amps, are more then up to the task. It is bad practice to do what I think you are trying to do. This will cost a lot of money to cause problems. This is in fact one of the huge arguments for separate preamps and power amps. The more preamps and processing circuits benefit, but power amps do not. You are making this too complicated and making for inferior engineering.

 

[ssmokeyy]

Im always on the side of amps always go to wall and u protect avp and anything computer based. But this problem is driving me nuts. I want to do it correctly but the noise wont go away and I do not feel good about not using the ground. I do not like bandaid for problems. I know the power conditioner is another kind of bandaid but some of these boxes have storage banks for rush current. Way over priced.

 

[TLS Guy]

Im always on the side of amps always go to wall and u protect avp and anything computer based. But this problem is driving me nuts. I want to do it correctly but the noise wont go away and I do not feel good about not using the ground. I do not like bandaid for problems. I know the power conditioner is another kind of bandaid but some of these boxes have storage banks for rush current. Way over priced.

Sorry, but you have no clue. You don't seem to have the knowledge to design and install a good quality system.

The power supplies of well designed amps will do everything and more than a power conditioner. Power amps all have huge caps for rush current. If they did not they would be no good. You will need to use grounds correctly and not causing issues with grounds at different potentials. You can ground your plate amp. But you you can prevent the loop and hum with that xlr ground break. There is nothing dangerous or wrong with that. It is the correct solution to your problem, In fact if you do what you propose you will recreate your ground loop and the noise.

 

[ssmokeyy]

I have tested hooking up the plate amp to the power conditioner that the av20 is plugged into . Noise gone. So trying to find a larger amp load rated item is a bad idea. Not sure i see where your going with that one. How would have u set this up different using 5 amps all wanting 15 amps of power or more with one outlet so u dont get ground loops and the avp needs power Also?

 

[PENG]

Just sucks that the ground wire from the av20 to the plate didnt work.

That almost never work, but people keep spreading that semi myth (semi because in some rare case/condition it might work, though still not recommended, not by me anyway).

The better way to fix that is to do it at the plate amp's XLR connection, it usually is the what Hypex call the pin 1 issue.

I posted the relevant documents several times on this forum, below is one of those you may want to read if you are still interested in fixing it properly. You are right about converting a 3 prong to 2, that usually is not a good idea, manufacturers use 3 prong for good reasons.

AN Dealing with legacy pin 1 problems

 

[TLS Guy]

I have tested hooking up the plate amp to the power conditioner that the av20 is plugged into . Noise gone. So trying to find a larger amp load rated item is a bad idea. Not sure i see where your going with that one. How would have u set this up different using 5 amps all wanting 15 amps of power or more with one outlet so u dont get ground loops and the avp needs power Also?

I have nine powerful two channel amps powering my AV room, plus electronic crossovers and a lot of ancillary equipment. I don't have any hum and the room is silent. Our great room and family rooms have two, two channel amps each and none of them hum.

What I suggest you do is have your power amps on a different circuit to the ancillary equipment, but bond the grounds with a massive copper link.

The low power equipment can be powered from uninterruptible power supplies and I have one in each of my three 19" racks in the studio. By the way for complex systems like yours a 19" rack well grounded is a very good idea.
The power amps are on two circuits and the low power on another. Now UPS units will not protect you from surges. Your best protection is following NEC code, which I strongly recommend. That means a type 1 at service entry to your home and SPD 2 in every electrical panel. I have two panels, so I have one SPD 1 and two SPD 2s.

In your case you have a problem as your your plate amp is obviously on a different circuit to the rest and a different potential to ground.

So you have two options, cut the ground to your plate amp from your main system with the xlr ground break.

You other option is to route a power cable from you pre/pro circuit along with the xlr cable, so the plate amp has the same ground as the rest of the system.

This is all logic and understanding the physics of the system. The solution is not to throw money at costly devices you don't need and may well make matters worse.

Not a lick up hum. Room dead quiet.

 

[ssmokeyy]

Before I built this room I had a new panel put in with both spd 1 and spd 2. How long have u had that setup? This is the first time I have had this problem. I have a stack of theater design, electrical design, room design books about 2 feet tall but since I never add it before I had no clear what the problem was. Do u have anymore pics of how u did that ground cable to all the gear? I would have love to do a rack but didnt have the space. I had to build to racks of different sizes to fit rhe gear in the room. Its a small room. I have a son that gets into every and breaks things. So we have to limit access to rooms. Other wise I would have had the rack in my office. Office has no doors.

 

[ssmokeyy]

Found the forever fix. Tested and no noise. Going to move my 30 amp breaker to another outlet pair. I will post my crap drawing once I get it done. All ground items on the same line with out hurting output. And no xlr lifter needed.