Broken Denon x2600h

[Mitzy]

So I got this amp a little while ago, I think within the last 2 years. Problem is I have 2 small children and the AMP was front and centre in the room, you can see where this is going..

Anyhow, the amp produces an audible buzz when powered on and nothing connected. No buzz from the speakers but the subwoofer picks it up unfortunately and it's really annoying! If I disconnect the RCA to the sub then the buzzing stops in the subwoofer but not on the amp.

I really don't want to buy a new amp.

As a result I have moved all the AV stuff into a closet beside the living room to keep it safe from little hands. While doing that I opened up the amp and the amount of crud the little ones had smooshed inside of it was impressive lol

Is there anything I could do to diagnose and fix the problem myself, I am handy enough so appreciate any advice

 

[-Jim-]

Sorry to hear about your situation. Assuming the "crud" is causing a ground loop resulting in this "new" hum noise, my obvious take would be to remove said crud. Can you post a photo of what's there now so we can review and offer good guidance?

I'm thinking with the unit unplugged, delicate mechanical removal of the crud, followed by a complete rinsing of the affected area with electrical contact cleaner (with the receiver up side down as to not wash it further into the bowels of the unit) could work. There's no guarantee as damage to components (shorted) may have already occurred by the crud.

But photos would tell the tale of next steps.

 

[Teetertotter?]

Perhaps remove the cover and use a paint brush to remove any crumbs on the PC board and other components. See what happens. Make sure you unplug the unit before working on it. Make sure no metal objects come in contact with any of the components.

 

[Mitzy]

Thanks for the replies gents! I should have said this from the start but I did try and remove the crud. I've got before pics but I forgot to take an after. You can see this was quite disgusting lol I did get most of the big stuff, used a vacuum with brush attachment. No change to the buzz though

Spoiler

 

[Mitzy]

I'm sorry about the image quality I couldn't upload the original files, they were too large. Had to use Imgur

 

[TLS Guy]

So I got this amp a little while ago, I think within the last 2 years. Problem is I have 2 small children and the AMP was front and centre in the room, you can see where this is going..

Anyhow, the amp produces an audible buzz when powered on and nothing connected. No buzz from the speakers but the subwoofer picks it up unfortunately and it's really annoying! If I disconnect the RCA to the sub then the buzzing stops in the subwoofer but not on the amp.

I really don't want to buy a new amp.

As a result I have moved all the AV stuff into a closet beside the living room to keep it safe from little hands. While doing that I opened up the amp and the amount of crud the little ones had smooshed inside of it was impressive lol

Is there anything I could do to diagnose and fix the problem myself, I am handy enough so appreciate any advice

So that is a four year old receiver.

My first question is this: - Is there a hum from all speakers with ONLY the AC mains and main speakers connected? This is important, as if the answer is yes, then there is no external ground loop. If you have done a good job of cleaning then this is probably not an internal ground loop. What I would do for completeness is to spray the unit with two or three cans of compressed air. If you have access to compressor and air gun, without oil added to the air stream, then that would be even better.

If the unit still hums, then that crud has most likely caused an aberrant current pathway between some critical components, most likely in the power supply board, and caused damage.

If this is the case, then unless you are experienced and own extensive test gear you will not fix it, but cause further damage.

Unfortunately there are no local guys who can fix this gear any more. Unless they are an authorized service center they don't have access to manuals and software.

So this unit will need to be sent to an authorized service center.

Due to the age of this unit, the cost of repair and shipping is probably worth it. Although I suspect the cost of repair and service will be at least half the cost of a new receiver at least.

That leaves you with the other option of recycling and a new receiver.

 

[Trebdp83]

Yikes, time to look at new receivers and orphanages.

 

[lovinthehd]

Thanks for the replies gents! I should have said this from the start but I did try and remove the crud. I've got before pics but I forgot to take an after. You can see this was quite disgusting lol I did get most of the big stuff, used a vacuum with brush attachment. No change to the buzz though

Spoiler

Wow! If your sub is ported might want to see what's in there, too Would love to see an after pic if you open it back up!

 

[TLS Guy]

Thanks for the replies gents! I should have said this from the start but I did try and remove the crud. I've got before pics but I forgot to take an after. You can see this was quite disgusting lol I did get most of the big stuff, used a vacuum with brush attachment. No change to the buzz though

Spoiler

I have just opened that picture. There is way too much damage to that board for it to even be safe to use any more. Sorry, but that receiver is done for,and needs recycling.

 

[-Jim-]

@Mitzy , Thanks for the photo. I wish you had an "after" one as well.

I'm always hopeful, so I maintain my first comments above. Rather than just take it to the recycler, buy a can or two of electrical contact cleaner (spray) and give it a thorough going over where ever you see crud, while you have it tipped upside down. Blow it off with Clean Air or let it air dry in a warm location for 24 hours.

I think the small cost is worthwhile at this point.

 

[TLS Guy]

@Mitzy , Thanks for the photo. I wish you had an "after" one as well.

I'm always hopeful, so I maintain my first comments above. Rather than just take it to the recycler, buy a can or two of electrical contact cleaner (spray) and give it a thorough going over where ever you see crud, while you have it tipped upside down. Blow it off with Clean Air or let it air dry in a warm location for 24 hours.

I think the small cost is worthwhile at this point.

You can see serious corrosion on that board and it is now dangerous.

 

[-Jim-]

You can see serious corrosion on that board and it is now dangerous.

I'm sorry, and not to seem rude, but I think this a bit over dramatic. If after cleaning the receiver could fail internally, and draw too much current and trip the breaker; or possibly pop an internal fuse. But then a brand new one could due the same if something fails internally. That's why those protection devices exist.

When it was first (partially?) cleaned and energized, there was a risk of failure and my suggestion should reduce that risk somewhat.

I do acknowledge there is more risk for failure after cleaning than a new receiver, but I'd have no issue in trying the remedy I suggested. (And I have done this on occasion with various electrical and electronic devices.)

@Mitzy If you try my suggestion (not that you have much to lose) be cautious when first energizing and powering up.

Remember the first rule of electronics => Don't let the smoke out!

 

[lovinthehd]

Reminds me of those pics of amps being washed with suds n hoses.....supposedly if dried well they could work again in a while

 

[Mitzy]

Thanks for all the replies, I really appreciate all your different thoughts. I know the amp is done for, for now I have just disconnected the subwoofer and set my fronts back to "full" to compensate. I am actively researching a new amp, I figure I'll get something a bit above budget this time as a treat to myself but I've got a holiday in the next couple of months and I need to set money aside for that first.

I'll try and get into it again, remove the cover and have a go at it with come compressed air too. My girls are little devils they also ripped off the antennas and the smallest one liked to climb up on top of the amp. Nightmare but all tucked away safley now. At least the next one will be safe

Also yes, 100 there have been liquids spilled on the top, most likely from banging sippy cup on the top repeatedly lol

 

[highfigh]

Sorry to hear about your situation. Assuming the "crud" is causing a ground loop resulting in this "new" hum noise, my obvious take would be to remove said crud. Can you post a photo of what's there now so we can review and offer good guidance?

I'm thinking with the unit unplugged, delicate mechanical removal of the crud, followed by a complete rinsing of the affected area with electrical contact cleaner (with the receiver up side down as to not wash it further into the bowels of the unit) could work. There's no guarantee as damage to components (shorted) may have already occurred by the crud.

But photos would tell the tale of next steps.

Edited, because I was being a dik dik.

 

[highfigh]

So I got this amp a little while ago, I think within the last 2 years. Problem is I have 2 small children and the AMP was front and centre in the room, you can see where this is going..

Anyhow, the amp produces an audible buzz when powered on and nothing connected. No buzz from the speakers but the subwoofer picks it up unfortunately and it's really annoying! If I disconnect the RCA to the sub then the buzzing stops in the subwoofer but not on the amp.

I really don't want to buy a new amp.

As a result I have moved all the AV stuff into a closet beside the living room to keep it safe from little hands. While doing that I opened up the amp and the amount of crud the little ones had smooshed inside of it was impressive lol

Is there anything I could do to diagnose and fix the problem myself, I am handy enough so appreciate any advice

I have seen beer sloshed into a receiver but because we shut it off and unplugged it immediately before removing the liquid, it worked fine afterward. When the beer entered, the receiver relays clicked and then it started to hum loudly.

I would unplug it and clean out the stuff, but not with a water-based liquid and definitely not by spraying anything in/on the circuit boards. Use a cheap paint brush and remove anything that's loose (any ideas what the crud is?). Is the crud dry or able to dry? That matters.

We used a paint brush, wiped it with paper towels, then used a blow dryer set to low heat to dry it.

It wasn't the first time I saw electronics that had some kind of moist substance or liquid on the circuit boards and there's no guarantee that this will work, but I would try it.

 

[-Jim-]

A ground loop is electrical, not caused by dirt!

Find definitions before posting about this stuff.

For what it's worth - I'm a licensed Electrician with Electronic Technologist training on top (amongst other skills and training), and I certainly know what contamination can do to circuit boards. At one time I was the manager of a Service Engineering Department at General Electric for a couple of years, and my team did installations and AC or DC Drive Systems servicing (including Synchronous Motor, Steam Turbine, and Hydro Electric generation excitation). Primarily it was Industrial - think Pulp and Paper Machines, Refiners, Portside Container Cranes, Mine Hoists, Cement Plants, Ships, etc. I had Engineers, Technologists, Technicians, and Electricians working under me. We had Customers find ways to put "Crud" into drives in many ways causing grounds, ground loops, component, power supply, and card failures all the time. I know my way around electronics and electrical devices including High Voltage. I was a published Author for IEEE, and an active member on Committees for over a decade. So please don't tell me what a ground loop is.

 

[PENG]

For what it's worth - I'm a licensed Electrician with Electronic Technologist training on top (amongst other skills and training), and I certainly know what contamination can do to circuit boards. At one time I was the manager of a Service Engineering Department at General Electric for a couple of years, and my team did installations and AC or DC Drive Systems servicing (including Synchronous Motor, Steam Turbine, and Hydro Electric generation excitation). Primarily it was Industrial - think Pulp and Paper Machines, Refiners, Portside Container Cranes, Mine Hoists, Cement Plants, Ships, etc. I had Engineers, Technologists, Technicians, and Electricians working under me. We had Customers find ways to put "Crud" into drives in many ways causing grounds, ground loops, component, power supply, and card failures all the time. I know my way around electronics and electrical devices including High Voltage. I was a published Author for IEEE, and an active member on Committees for over a decade. So please don't tell me what a ground loop is.

It's the internet Jim, our qualifications don't mean much to people who think they can learn/understand everything online, free or paid... Sometimes, knowing a little could be more dangerous than knowing nothing!

 

[TLS Guy]

A ground loop is electrical, not caused by dirt!

Find definitions before posting about this stuff.

An internal ground loop certainly can be caused by an internal poor ground. Especially in the unit under question. There is going to be corrosion in the grounds of cable connectors and board pins. I would bet there is raised resistance to grounds all over that unit.

This unit might possibly be salvaged by a total dismantling and cleaning of every press fit connection with tuner cleaner, Q-tips and compressed air. Every single board will need careful cleaning. There will be hundreds of hours involved cleaning this unit up. Then at the end, this situation may have done some component damage and a lot of hard work will be for nothing.

Lastly, I would point out, that in the design of any unit, the internal ground plane needs tremendous thought and care. Even small mistakes to the design of the ground plane can really bite you.

 

[highfigh]

For what it's worth - I'm a licensed Electrician with Electronic Technologist training on top (amongst other skills and training), and I certainly know what contamination can do to circuit boards. At one time I was the manager of a Service Engineering Department at General Electric for a couple of years, and my team did installations and AC or DC Drive Systems servicing (including Synchronous Motor, Steam Turbine, and Hydro Electric generation excitation). Primarily it was Industrial - think Pulp and Paper Machines, Refiners, Portside Container Cranes, Mine Hoists, Cement Plants, Ships, etc. I had Engineers, Technologists, Technicians, and Electricians working under me. We had Customers find ways to put "Crud" into drives in many ways causing grounds, ground loops, component, power supply, and card failures all the time. I know my way around electronics and electrical devices including High Voltage. I was a published Author for IEEE, and an active member on Committees for over a decade. So please don't tell me what a ground loop is.

Sorry, didn't know the extent of your knowledge. It was definitely an over-reaction.