One of my NAD's channels is messed up

[jostenmeat]

A few of you might have noticed in the "shorter interconnects" thread where I mentioned having some buzz from a surround channel. Well, last night I had intermittent "pops", which was very annoying. While the unit worked just great for 1.5 yr, maybe I shouldn't buy refurbed anymore. Or maybe I shouldn't buy NAD anymore. Or perhaps particularly NAD refurbed products. Its a T-973.

So, I called my dealer, and he has recommended me to a particular service center. He said the hourly rates are in the ballpark of $60-80.

I don't know whether to give up on this amp channel, take my losses, and use my receiver's amp channels for the rears. Or if I should bother to take care of this channel.

I'm just afraid of how much this might add up to just to find out what's wrong, let alone fixing the issue. The service center is a decent jaunt away, and the amp is 70 lbs or so.

Grr.

Meanwhile, I am in the midst of getting my espresso machine repaired at the same time. My faulty water pipe has been fixed as of last week, and drywall is up. Have to install one access panel. Why does everything break at the same time?

Anyhoo, maybe someone can help me diagnose it here? Before I pull it out and lug it, I'll see if it happens with other movies first. Last night, I put on a gift, Harold/Kumar-Gbay. Night before was the Hendrix concert, and some classical. Couple nights before that was Dark Knight. No issues with these titles, but I wonder if the amp channel could be "stressed" from recently higher volumes. Meh, I know it should* work fine, but maybe that's another clue for someone to help me with.

Thanks.

edit: the present Outlaw sale does look enticing . . . it sure would be nice to have a 5yr warranty too . . . bah . . .

 

[strube]

I had a NAD (T754 or T753 I think) receiver for a little over a month before I got my Rotel. It was so plagued with problems (totally random popping audio, fans were introducing feedback into the speakers, the display would corrupt randomly, optical inputs were flaky) - I took it back and the dealer was kind enough to refund my money (after some some diplomatic prodding ), but had the gall to say that "experienced" people like NAD products and never have any problems with them. I found out later on many forums that many "experienced" people had the same problems. I would have probably gotten something else even if I couldn't have gotten all my money back.

Anyway, I know I will never buy another NAD product, in my eyes their quality control had some serious issues, plus the large sum of money I shelled out (don't remember exactly but it was a lot ) was difficult for a cheap college student and I felt it should work perfectly for that price. I know I am just one person and tried only one receiver, and it was a few years ago, but I wanted to rant .

 

[emorphien]

I have read of problems with their AV receivers and have to say I probably wouldn't buy one for myself. I own three NAD products, an integrated amp, cd player and and phono preamp and the only one that gives me any trouble is the CD player after a cold start from power outage, etc. It's frustrating but I haven't felt annoyed enough to do anything about it at this point and it's out of warranty.

Their stereo amps, without all the digital whatnot, seem to fare better and I absolutely love my C320BEE. No complaints about the PP-2 phono preamp either. I would but a NAD stereo amp or integrated amp again.

My parents have one of the NAD 5 channel receivers (I forget which) and a NAD dvd player which was coincidence really but apparently they've had no problems with either in the past couple years although I was a bit concerned.

 

[Tomorrow]

There is nothing worse than having your nads stop working.

 

[3db]

I know NAD suffered from quality control about 5 years ago or which would date strube's receiver about right. I was hoping that this quality control problem hasd been cured within the last 2 to 3 years. There's no need for a lack of quality nor is there any room for lack quality either.

What year is your T973 Jostenmeat?

 

[pearsall001]

I bought my NAD T773 avr back in Feb of '04. Within the warranty period I had to send it in for repair. The digital boards had to be replaced. The unit worked great until about 4 months ago. It would give off a very, very loud pop sound thru the front speakers when I changed inputs via the remote control. Back it went for repair, they fixed the problem (on my dime). When I got the unit back it started making a hiss/hum noise (very audible) thru my mains. It didn't do this until I got the unit back from the repair.

Long story short...back it went again, & back it came...still not fixed right. They said they didn't hear any noise from the speakers. Luckily for me my dealer was there when I checked it out & for sure the noise was still there. Packed it up & sent it back again.

In NAD's defense, the latest repairs were at no cost to me (except I had to pay S&H to ship it out). NAD replaced a lot of componets this time & they finally admitted hearing the speaker noise. It'd due back this coming Mon or Tues. This puppy had better be fixed!!!!!! I too am losing confidence in NAD after this experience. But I do love the T773's musical sound & performance.

I'm currently in the market foe a new prepro & I'll just be using the T773 as a power amp for my rear surrounds. I do think they had serious issues a few years back & I really don't know about the quality of their new gear. Hopefully their qualiyu control has been greatly improved.

 

[markw]

Well, that sux.

Dunno that I'd go for NAD AV gear. Two channel stuff, yes, but not their AV gear. I've been lucky with their two-channel stuff (the newest from '98 or so)

I haven't heard too much good about their AV line, and this goes back to the days of the 750 and such. This goes for realiability as well as a common sparsity of features per dollar, particularly as far as video goes.

When you find the problem (assuming you do pursue this), I/we would like to know the cause.

I've always thought their strengths were in the power amp areas and, as such. would probably go with a different front end receiver and use external NAD power amps with them.

Good luck. It pains me to see a formerly respected line become known for failures.

 

[jostenmeat]

Thanks guys for sharing your input and experiences. I'm trying to look on the bright side: hey, I still have 6 channels that are working just fine.

I'm going to swap some wires around soon, and run one of my rear speakers off the receiver. If I ever have another channel go out on me, Im going to run both rears off receiver. If I have a third channel eventually go out on me, then I will more seriously consider pro repair.

I just met an EE last night, but I completely forgot to ask her if she could help me with my problem. She is now in the marketing aspect I think, but she was previously involved with design. I'm sure she must know someone who can help for less than $80/hr, if she can't herself, and be a lot closer to me as well.

I'll give that a shot hopefully, and less that, I'm just not going to do anything about it for now.

I am going to re-re-re-check wiring, and make sure the speaker is still healthy. I'm pretty darn sure its the amp channel though. Quite sure.

In building my system over the last two years, I've bought refurbished numerous times, open-box, used, blemished, demos, superceded, etc. I think my penchant for savings finally bit me in the azz. Hah.

Next time I buy, I am going with NIB! That'll be cool.

Thanks again, neat to see some NAD owners come out of the woodwork here. I honestly don't think I'm going to buy NAD again, however. If I did it all over today for a mch amp, I think I'd be leaning towards Outlaw. I'd be tempted by a used Rotel or Sunfire, but I'm going to see if I can talk myself into NIB, hehe.

3db, my amp was bought in the spring of last year, and as its refurbed, I'm sure it must be older than that.

pearsall001, your experience is exactly what I'm afraid of. Throwing time and money at temporary fixes, or worse yet, just throwing money away. I know you aren't to great extent, but I'm in a different boat, past warranty. Please let us know how it goes, and I will do likewise if I try to get it repaired.

Cheers.

 

[bandphan]

Whispers...... McIntosh. Close to 30 years

 

[jostenmeat]

Haha. I haven't been into this stuff long enough to be enticed by that brand name like many others. For all I know, I could probably buy a new Outlaw every 5 years for the same price as some single Macs! haha

I would even consider pro amps, except I don't want to create more space, and have more cabling, besides other things such as aesthetics or fan noise. The price difference between 4x pro amps and say an Outlaw is not great enough for me to deal with that . . .

Thanks anyways, I suppose.

 

[bandphan]

Its all good. I just appreciate the build quality and the esthics and wish my poor arse could afford more.

 

[strube]

I just met an EE last night, but I completely forgot to ask her if she could help me with my problem. She is now in the marketing aspect I think, but she was previously involved with design. I'm sure she must know someone who can help for less than $80/hr, if she can't herself, and be a lot closer to me as well.

I doubt she could help you directly, but she could maybe help you get in touch with a tech that had the right test equipment to diagnose the problem. I have an EE undergraduate degree, and have theoretical and design knowledge of electronics, but unfortunately we (usually, except for testing engineers) rely on technicians and automated machines for the actual building of said electronics, and also diagnosing problems with actual equipment (determining exactly which op amps/capacitors/inductors/transistors/resistors/etc. are toasted). Then those same technicians hopefully report to us so we can design the next version with more robust components .

Of course, I am still in school and don't really have any real world experience, so I may find out I am completely wrong shortly.

EDIT: I think I need to give us EEs a bit more credit than that - she could certainly check simple things like proper grounding to the amp's PCB (the line may have corroded or something and made the ground connection sketchy), leaky capacitors, etc. however, one must be extremely careful, as even unplugged, the amp will have deadly energy stored in the many capacitors throughout the system, and it should probably only be cracked open and prodded at with test equipment by someone who really knows what they are doing.

 

[jostenmeat]

Thanks strube, good stuff, appreciated.

 

[jostenmeat]

So, it seems the amp channel only popped during that one movie. Maybe its a bad disc, or got damaged somehow. Its just too strange that the popping happened on the one channel on one movie.

Something I noticed was that when I fired up the amp, the 7 green lights all turn on, but the "faulty" amp channel lights up a split second later. (When I hit the power, they all turn red for a moment, then green a second later).

Does the above help in any diagnosing?

Otherwise, for now, the amp channel just has a bit more residual noise than the others.

hmrz . . .

 

[jostenmeat]

Anyhoo, maybe someone can help me diagnose it here? Before I pull it out and lug it, I'll see if it happens with other movies first. Last night, I put on a gift, Harold/Kumar-Gbay. Night before was the Hendrix concert, and some classical. Couple nights before that was Dark Knight. No issues with these titles, but I wonder if the amp channel could be "stressed" from recently higher volumes. Meh, I know it should* work fine, but maybe that's another clue for someone to help me with..

You guys aren't going to believe this. Its the stupid Harold/Kumar BD when using fully decoded MA that makes crazy pops.

During the viewing, it appeared pops did happen from the other side surround too, but they were pretty bad on the right side. Maybe the amp channel that is not as "healthy" just hated the pops more than the other channel(s). I've heard that its supposed to be soft popping on a bunch of channels. If true, I find my experience to be particularly strange, and I wonder if that would be some sort of clue for an amp expert. Bah.

Anyhoo, its all working fine for now. Too bad about the disc, and no replacement program yet announced according to this thread I just found . . .

Blu-ray Glitch List - Titles you might want to avoid

edit: I oughta post this link in the software forum I suppose....

 

[deedubb]

Did you try playing the same movie but running the surrounds off the receiver to see if the pops still occur?

FWIW, I have the same amp, love it and have had no problems. I have read about some quality control issues with NAD in the past though. This is my first NAD product.

I wouldn't hesitate to buy refurb in the future. My own thinking is that refurb products are examined with a fine toothed comb to ensure that any potential problem is fixed and may actually be less likely to break down compared to a NIB product, but I don't have any evidence to support this. The only refurbished item I've ever purchased is my Macbook Pro and it works like a champ.

Anyway, if there is a problem, I'd stick with your plan of running the surrounds off your receiver. The surrounds are the least important of all the speakers anyway and I'd bet you won't really notice any difference in sound.

 

[jostenmeat]

Did you try playing the same movie but running the surrounds off the receiver to see if the pops still occur?

Not yet. And to hell with that BD title. No way I'm ever putting it on to test pops; if I ever do put it on, it won't be with the full MA track.

FWIW, I have the same amp, love it and have had no problems. I have read about some quality control issues with NAD in the past though. This is my first NAD product.

I love mine too, man. Its a GREAT amp for HT. I had electrostats that drop to .7 ohm hooked up to em for a while as well. Between the affordable pricing and 2 ohm stability, there weren't many choices in my eyes at the time.

I wouldn't hesitate to buy refurb in the future. My own thinking is that refurb products are examined with a fine toothed comb to ensure that any potential problem is fixed and may actually be less likely to break down compared to a NIB product, but I don't have any evidence to support this. The only refurbished item I've ever purchased is my Macbook Pro and it works like a champ.

I'm the refurb master! My Onkyo receiver (pre) is refurbed. My previous NAD t173 was refurbed (while I didn't care of its issue, it was unable to properly matrix analog inputs). My PJ is open box. All 7 HT speakers were bought as blemished (though dealer gave me new on a few of them when color wasn't available). My stereo speakers are demo's. I have hundreds of pounds of used acoustical panels. My integrated was bought as a superceded item. I've had great luck I suppose, and while I worry now and then, so far so good.

Anyway, if there is a problem, I'd stick with your plan of running the surrounds off your receiver. The surrounds are the least important of all the speakers anyway and I'd bet you won't really notice any difference in sound.

Everything is on the NAD for now. Its fine for now. I may not notice much difference, its possible. Then again, you don't know how loud it can get! And my surrounds are b25s that do drop to 3.7 ohms.

Anyways, nice stuff you got in your sig man. We both use NAD, PSB, LCoS based PJ, separate systems... except you have 3 of em + anamorphic.

 

[Jens_Denmark]

I bought my NAD T773 avr back in Feb of '04. Within the warranty period I had to send it in for repair. The digital boards had to be replaced. The unit worked great until about 4 months ago. It would give off a very, very loud pop sound thru the front speakers when I changed inputs via the remote control. Back it went for repair, they fixed the problem (on my dime).

PLZ tell me what they did to repair the "pop sound".
I have a T763 and it has worked great until this afternoon where it suddenly began sending dc pops through the front speakers - it nearly killed them!
I have made factory resets but nothing seems to help. The pops also comes when the volume is turned all the way down to mute.

Thanx