Denon X3700H and Amp? (nothing but hum)

S

Sachb

Audioholic
I had hum on my Sub when it was connected to the Denon reciever. The hum is gone now, with the Yamaha.

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S

Sachb

Audioholic
So you believe OP's AVR Is defective?
It could be, since it's a Denon.

I remember once I connected my Denon in-ear monitors to the Denon AVR, and guess what, I got an electric shock in my ear. It was slight but yet painful.

I'm thinking there could be a possibility of a ground loop. Every reciever does that, but on Denon its more severe.

The boston sub did hum on my Denon, and it could be heard when there was pin drop silence.




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S

Sachb

Audioholic
Thanks TLS Guy - I did try plugging the Outlaw into another surge protector separate from the Monster PS. It didn't seem to make a difference. I will try to completely disconnect the Cox STB tomorrow though - I did try unplugging it and that didn't make a difference (although the RG6 coax was still connected to the STB and HDMI was connected from the STB to the Denon). Either way - I have several great options to test out:

1. use 3:2 converter (non grounded amp).
2. fully disconnect coax/unplug coax STB
3. confirm amp powered on separate outlet(s) with coax/STB disconnected
4. ground amp to avr(?) per Outlaw manual on p5 - not sure the best way to do this as there's no dedicated ground terminal on the Denon

Thanks again everyone.
Do you have any other AVR to test?
Try plugging the outlaw amp to some other AVR. Borrow it from a friend even if you have to.

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TLS Guy

TLS Guy

Audioholic Slumlord
Do you have any other AVR to test?
Try plugging the outlaw amp to some other AVR. Borrow it from a friend even if you have to.

Sent from my LM-G710 using Tapatalk
Stop peddling BS. This is going to be a ground loop problem. And your previous one almost certainly was as well, and could have been solved with intelligence and not changing a receiver. If you have nothing sensible to add, then keep quiet.
 
RichB

RichB

Audioholic Field Marshall
As others have posted it is likely a ground loop.

First, I would connection the amp and make sure with no inputs connected there is no hum.
Next, remove all connects from the 3700. Unplug everything else and plug in only the 3700 and amp.
Do not use the power surge at all plug both into the same wall circuit.

Then, introduce the HDMI for the monitor, also plugged into the wall socket directly.

Rinse and repeat.

- Rich
 
S

Sachb

Audioholic
Stop peddling BS. This is going to be a ground loop problem. And your previous one almost certainly was as well, and could have been solved with intelligence and not changing a receiver. If you have nothing sensible to add, then keep quiet.
Did you even see what you posted on one of your previous posts? What has internet cable got to do with ground loop.

Utter nonsense.

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mazersteven

mazersteven

Audioholic Warlord
Whoa! hold up there, Wait what! "Utter nonsense" really? You do realize and if you don't, TLSGUY aka Doc, is A very well respected member on AH. Highly educated in the field of Medical science. Aka PHD, If you don't piss him off but I feel you may have already done a good job of that. Doc, would've been more than happy to share his knowledge with you. I'll say this I've been reading some of your post, most of them do Nothing at all but bashing Denon and slandering a good company. Denons good gear, don't kid yourself about Yamaha there not as Bulletproof as you think. I have two Yamaha AVR's like them I do, and they have gimmicks just like ever AVR has. I would bet my last buck that if you had a Denon and Yamaha side by side All Things being set equal, with a Blindfold over your eyes :rolleyes: you would not, No could Not tell which AVR was playing the sound. I see you ran into loveinthehd, aka Chris, doesn't need any help with Defending himself as the other ole timers don't need defending either. Sure Chris can be a meatball:D:p and some of his post are a little deranged and come across as condescending some of his post are;). But so are some of my post:D. Keep doing what you doing, TLSGUY done hit You with one of his Haldol sedative shots. o_O But I feel you may end up in @gene ,jail for a week. :(Gene doesn't take to kindly to gear bashing of any kind. Gene and the Mods are forgiving but to a point. Just chillout bro, you found you last forever AVR and you happy with it.:) Enjoy your hobby as only You can.
Wow I'm impressed with the serious talk and the statement I like most is about the meatball.

And just to put this out there he's already in the crosshairs.
 
Tony Cardenas

Tony Cardenas

Junior Audioholic
Ok folks - to start - I wanted to thank everyone for the time and energy troubleshooting this. So once I had a large cup of coffee - it was time to work this issue.

I started with what I considered would be the easiest (but felt wasn't going to work - couldn't be that easy) - I used a short cheater A/C cable with a 3 prong connect for the Outlaw and the other end with 2. I connected FRONT LEFT, FRONT RIGHT, and CENTER speakers to the Outlaw. Ran my initial short set (1.5ft) RCA interconects from the Denon pre outs to the Outlaw. Plugged in power, powered up everything and BAM! NO HUM! Tested with TV, movies, and currently listening to a nice jazz track. The silence is (as far as I can tell) absolutely quiet. I have my ear right up to the speaker and I can't notice any hum or any other adverse sounds at all. Pumping up the volume to 70% - sounds crystal clear to me. Again - I am by no means an expert and wouldn't consider having a sharp ear for it - but as a layperson - things are sounding fantastic. Same crystal clarity as when I had the AMP removed. I haven't connected the trigger cable between the Outlaw and Denon, but I'll get that connected and hopefully working too (want the Denon once powered on to control the Outlaw).

I guess now the issue is should I try to troubleshoot further - maybe remove coax, etc. Its obviously having issues with the ground pin on the Outlaw. If I ground the Outlaw chassis with a nice solid core copper line to the power center's dedicated ground - would that be sufficient to at least make things safe?

As I said before - this forum is a fantastic resource. I've been a lurker for a long time and never joined. I will probably be much more active here now and in whatever small way I can - try to contribute. Many thanks and I wish a great Sunday to everyone here.

- - - - -
grammar edit
 
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VMPS-TIII

VMPS-TIII

Audioholic Chief
Congrats, Now you know its a ground loop. I would download any of the Outlaw on line amp manuals and walk thru the suggestions they offer to correct the issue.
 
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Tony Cardenas

Tony Cardenas

Junior Audioholic
Congrats, Now you know its a ground loop. I would download any of the Outlaw on line amp manuals and walk thru the suggestions they offer to correct the issue.
Thanks VPMS-TIII - I'm going to specifically follow their guide for sure (will connect dedicated ground from the Outlaw).
 
K

Kleinst

Audioholic
Ok - now I need to follow up and pick one of these up I guess :)
Yes buy one of those and move on. You could spend a lot of time trying to figure it all out but if the Hum X works for you (and it is around $70-$80) It's worth every dollar. Ground loop noises are maddening and have side tracked me for days at a time :)
 
K

Kleinst

Audioholic
QUOTE="lovinthehd, post: 1435657, member: 61636"]
Is it dangerous if you never touch the amp case?
[/QUOTE]

Honestly I don't know how dangerous it is. But It is my understanding that the HUM X lifts the ground in a safer way (than a cheater and I don't know the science behind it). I hope that's the case as I'm using on on one of my AMPS and it helps a lot. New they are kind of expensive for what they are but nice to have I guess.
 
Tony Cardenas

Tony Cardenas

Junior Audioholic
Yes buy one of those and move on. You could spend a lot of time trying to figure it all out but if the Hum X works for you (and it is around $70-$80) It's worth every dollar. Ground loop noises are maddening and have side tracked me for days at a time :)
Agreed! I guess I should consider myself lucky - I had almost a full day invested which isn't too bad. I've spent days nailing down issues before as well and was settling in to thinking I was in for another multi-day project (interspersed between work, honey do's, kids, and 1,000 other things). You guys saved me a boatload of time and frustration no doubt. If this was an actual in-person forum thing - it would be a round of drinks on me (or at least a coffee).
 
TLS Guy

TLS Guy

Audioholic Slumlord
Agreed! I guess I should consider myself lucky - I had almost a full day invested which isn't too bad. I've spent days nailing down issues before as well and was settling in to thinking I was in for another multi-day project (interspersed between work, honey do's, kids, and 1,000 other things). You guys saved me a boatload of time and frustration no doubt. If this was an actual in-person forum thing - it would be a round of drinks on me (or at least a coffee).
Those hum X units seldom work.

The correct way to solve your problem is the right way.

The problem with your current plan is that it is not safe at all.

At the moment your only ground is now the cable system ground. From what you have discovered this ground is highly suspect and is obviously a high resistance ground.

Not only that, but if your Outlaw should have a short to ground (this can and does happen), then the path to ground is then going to be up through your cables connecting it to your receiver, your receiver case, and all the way back through your whole cable system, to a suspect ground. If you did not understand this the first time then read it again.

Now, I am not clear on the grounding system of your cable system. Where possible the cable from your company should enter at a point close to your electric panel.
Code requires that it be bonded to the panel ground by stout copper cable. The panel should be strongly bonded to your house ground.

Now here is where codes vary. Some jurisdictions insist on grounding to water pipes AND an external house ground. I don't like this practice as it is a set up for ground loops. In my new residence code requires that the house ground be at entry of the water service. This is very good practice in my view. At my former residence it was the former. In order to prevent trouble I had to sink three large 6' rods, tied together and stoutly bonded to the electric panel. The house was on sandy soil and I had to keep watering the grounds, and make sure the ground was saturated before freeze up.

Finally I should point out that designing trouble free ground planes is a skill and art form.

As this residence as it was being built, I made sure that all ground led back directly to the water entry. In other words the whole house grounding system was designed and built as a classic "Star cluster" grounding system. The main panel is in the studio chase, and all rack grounds bonded and then to the panel. I have a nice quiet system.

In your case I need to know more, and preferably with pictures, to sort this out. We have to sort this, as your current plan is not acceptable.

All bonding the Outlaw to the receiver would do, is just provide another path for current to go back to the receiver other than the connecting cables. This could actually also set up another ground loop, and would if the cable screens have a significantly different resistance to your grounding cable.

At the forefront on this you need to keep this fact in mind, that ground loops are always caused by resistances between grounds. So ground plane designs are best thought of a spokes of a wheel, and to avoid circuitous ground paths. The latter are an invitation to loops and resulting hum.
 
T

TankTop5

Audioholic Chief
Those hum X units seldom work.

The correct way to solve your problem is the right way.

The problem with your current plan is that it is not safe at all.

At the moment your only ground is now the cable system ground. From what you have discovered this ground is highly suspect and is obviously a high resistance ground.

Not only that, but if your Outlaw should have a short to ground (this can and does happen), then the path to ground is then going to be up through your cables connecting it to your receiver, your receiver case, and all the way back through your whole cable system, to a suspect ground. If you did not understand this the first time then read it again.

Now, I am not clear on the grounding system of your cable system. Where possible the cable from your company should enter at a point close to your electric panel.
Code requires that it be bonded to the panel ground by stout copper cable. The panel should be strongly bonded to your house ground.

Now here is where codes vary. Some jurisdictions insist on grounding to water pipes AND an external house ground. I don't like this practice as it is a set up for ground loops. In my new residence code requires that the house ground be at entry of the water service. This is very good practice in my view. At my former residence it was the former. In order to prevent trouble I had to sink three large 6' rods, tied together and stoutly bonded to the electric panel. The house was on sandy soil and I had to keep watering the grounds, and make sure the ground was saturated before freeze up.

Finally I should point out that designing trouble free ground planes is a skill and art form.

As this residence as it was being built, I made sure that all ground led back directly to the water entry. In other words the whole house grounding system was designed and built as a classic "Star cluster" grounding system. The main panel is in the studio chase, and all rack grounds bonded and then to the panel. I have a nice quiet system.

In your case I need to know more, and preferably with pictures, to sort this out. We have to sort this, as your current plan is not acceptable.

All bonding the Outlaw to the receiver would do, is just provide another path for current to go back to the receiver other than the connecting cables. This could actually also set up another ground loop, and would if the cable screens have a significantly different resistance to your grounding cable.

At the forefront on this you need to keep this fact in mind, that ground loops are always caused by resistances between grounds. So ground plane designs are best thought of a spokes of a wheel, and to avoid circuitous ground paths. The latter are an invitation to loops and resulting hum.
Just because your builder didn’t do a good survey before building doesn’t negate grounding to water. Grounding to water rather than power is always preferable, that is if your home wasn’t built by a moron.
 
Tony Cardenas

Tony Cardenas

Junior Audioholic
Those hum X units seldom work.

The correct way to solve your problem is the right way.

The problem with your current plan is that it is not safe at all.

At the moment your only ground is now the cable system ground. From what you have discovered this ground is highly suspect and is obviously a high resistance ground.

Not only that, but if your Outlaw should have a short to ground (this can and does happen), then the path to ground is then going to be up through your cables connecting it to your receiver, your receiver case, and all the way back through your whole cable system, to a suspect ground. If you did not understand this the first time then read it again.

Now, I am not clear on the grounding system of your cable system. Where possible the cable from your company should enter at a point close to your electric panel.
Code requires that it be bonded to the panel ground by stout copper cable. The panel should be strongly bonded to your house ground.

Now here is where codes vary. Some jurisdictions insist on grounding to water pipes AND an external house ground. I don't like this practice as it is a set up for ground loops. In my new residence code requires that the house ground be at entry of the water service. This is very good practice in my view. At my former residence it was the former. In order to prevent trouble I had to sink three large 6' rods, tied together and stoutly bonded to the electric panel. The house was on sandy soil and I had to keep watering the grounds, and make sure the ground was saturated before freeze up.

Finally I should point out that designing trouble free ground planes is a skill and art form.

As this residence as it was being built, I made sure that all ground led back directly to the water entry. In other words the whole house grounding system was designed and built as a classic "Star cluster" grounding system. The main panel is in the studio chase, and all rack grounds bonded and then to the panel. I have a nice quiet system.

In your case I need to know more, and preferably with pictures, to sort this out. We have to sort this, as your current plan is not acceptable.

All bonding the Outlaw to the receiver would do, is just provide another path for current to go back to the receiver other than the connecting cables. This could actually also set up another ground loop, and would if the cable screens have a significantly different resistance to your grounding cable.

At the forefront on this you need to keep this fact in mind, that ground loops are always caused by resistances between grounds. So ground plane designs are best thought of a spokes of a wheel, and to avoid circuitous ground paths. The latter are an invitation to loops and resulting hum.
MAJOR UPDATE: I guess I should have just RTFM more clearly. I'm very embarrassed to admit this - I just ran a solid copper wire from the Outlaw grounding post to the signal ground on the back of the Denon. Plugged Outlaw in normal 3prong to the power center. No hum. I'm shaking my head - the time I spent going back and forth and wasting everyone else's time here. Now the $1,000,000 question - I'm assuming this is safe? The Denon isn't grounded (2 prong connection) and the Outlaw is.

What confuses me is in terms of safety - running a fully powered Denon receiver - wouldn't the same safety issues be at play (eg. if there was an internal short somewhere that electrified the unit and I touched it)?

Thanks again for all the help - I think I must be closer now hopefully (I'm tempted to leave things as is unless its unsafe).

Cheers everyone

- - - - -
EDIT - I didn't realize the Denon had a ground. Again - I should have read that manual more carefully too
 
TLS Guy

TLS Guy

Audioholic Slumlord
MAJOR UPDATE: I guess I should have just RTFM more clearly. I'm very embarrassed to admit this - I just ran a solid copper wire from the Outlaw grounding post to the signal ground on the back of the Denon. Plugged Outlaw in normal 3prong to the power center. No hum. I'm shaking my head - the time I spent going back and forth and wasting everyone else's time here. Now the $1,000,000 question - I'm assuming this is safe? The Denon isn't grounded (2 prong connection) and the Outlaw is.

What confuses me is in terms of safety - running a fully powered Denon receiver - wouldn't the same safety issues be at play (eg. if there was an internal short somewhere that electrified the unit and I touched it)?

Thanks again for all the help - I think I must be closer now hopefully (I'm tempted to leave things as is unless its unsafe).

Cheers everyone

- - - - -
EDIT - I didn't realize the Denon had a ground. Again - I should have read that manual more carefully too
That is interesting. Units with two pin and not three pin are double insulated and safe.

The fact that bonding the Outlaw to your receiver solved the problem means that Outlaw has a problem in its ground plane architecture. That has to mean that the grounds on the input of that amp are not at the same potential as the case, and the power cord grounding pin. They should be. There is a definite design error in the ground plane architecture of that Outlaw amp.
 
lovinthehd

lovinthehd

Seriously, I have no life.
Well, the Outlaw amp manual did suggest that particular use of the grounding post to combat ground loop hum.....
 

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