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Posted By: mwc Amp problem? - 12/16/03 09:30 PM
I drug out my beloved vintage Sansui intergrated amp today and hooked it up (feeling nostalgic I guess). I love this amp-lots of features and inputs with plenty of power (160w/ch) and great power meters.

The problem:
I hooked up the Maggies (4ohms) and the source (a tubed DAC) turned it on and got wonderful sound. But as soon as I touched the amp's chassis, after walking across the carpet, I got a static shock and the DAC instantly shut down. It happens when I'm charged up after walking across the carpet. If I touch something else before I touch the chassis it doesn't happen. Could this be an impedence problem (or am I blindly grasping at straws)? The amp's impedence switch has two settings: 8~16 ohm and 4~8 ohm. I had it set to 8~18.

Any electronics nerds (or even plain ol' nerds) out there with advice?
Posted By: pmbuko Re: Amp problem? - 12/16/03 11:53 PM
Sounds to me like the chassis and/or the entire unit isn't grounded. An electric shock to the chassis shouldn't cause the entire unit to shut down.
Posted By: mwc Re: Amp problem? - 12/16/03 11:54 PM
The amp didn't shut down, just the DAC.
Posted By: pmbuko Re: Amp problem? - 12/17/03 12:02 AM
Even stranger. It appears as though "the path of least resistance" (which is the way electricity always travels when given a choice) leads to the DAC.
Posted By: mwc Re: Amp problem? - 12/17/03 12:07 AM
I called my local electronics repairman and explained the problem. He said I should "junk it and get a new amp"....I hung up on him.
Posted By: Ken.C Re: Amp problem? - 12/17/03 12:33 AM
Whatta jerk. And someone who doesn't want repair business. Is there anyone else you could deal with? It sounds like it should be a relatively easy thing to fix, but I'm no EE.
Posted By: Haoleb Re: Amp problem? - 12/17/03 12:54 AM
Go over to :

www.audiokarma.org

and ask this question. Theres a dedicated Sansui forum and people that repair this stuff and what not. Tell em i sent you too so i can get another refferal lol.
Posted By: mwc Re: Amp problem? - 12/17/03 12:54 AM
The next closest repair shop is in Dallas about 30 miles away. If push comes to shove, I may trek on down there. I was hoping it would be an easy fix and that someone on some message board some where would have an idea. I only put the message out this afternoon so I may get some advice yet. There's one message board I haven't tried yet...woof! woof! .
Posted By: BrenR Re: Amp problem? - 12/17/03 12:58 AM
In reply to:

But as soon as I touched the amp's chassis, after walking across the carpet, I got a static shock and the DAC instantly shut down. It happens when I'm charged up after walking across the carpet.



Not exactly your original question, but you may want to look into an anti-static spray (a 4L jug is about $35CDN here) I'm somehow the most statically charged person in the world, and after getting shocked repeatedly in a most personal region leaning against the road cases as I cleaned the monitors in the arena video booth, someone bought a jug of the stuff (I'll look up a product name on Friday if you care)... haven't been shocked since, though it does leave a film on the carpet that makes it get dirty faster.

Bren R.
Posted By: mwc Re: Amp problem? - 12/17/03 01:11 AM
That's a good band-aid solution but I wan't to knock this problem out at the source because it's kind of sacrey. I'll have bad dreams about burning down my house or something.
Posted By: nowave Re: Amp problem? - 12/17/03 01:40 AM
It may be a grounding issue.

Does the Sansui have a 3 prong plug?

Does the DAC?

It would make sense that if the Sansui did not (which I'm sure it doesn't) but the DAC did, it might travel to the DAC.

You could probably solve it by wiring in a new 3-prong power cord and wire the ground plug to the chassis.

As with all cable, it's just not going to be right for audio unless the price of said power cable replacement approaches your rent (or mortgage) payments.

I hope that helps!!!

Posted By: chesseroo Re: Amp problem? - 12/17/03 04:57 AM
mwc,
First off, is there a reason you feel the need to touch the amp after it is turned on?
I suppose if you feel this need to touch your amp during playback then certainly you have a large problem.
However, you are not alone.
I am borrowing a friend's Phillips vintage preamp right now and it has a similar problem. When i touch the mute button, i sometimes get a popping noise and my left speaker channel cuts out. The only way to reset this problem is to shutoff the amp (not the Philiips preamp) and then turn it back on again.
The buttons on the Phillips are a touch sensitive design, not something i would personally put on an electrical device of this nature.
Anyway, to cut the story short, it is an electrical problem with grounding. There is no way to fix this in my situation unless an addition is made to the inside of the amp itself (some type of unit that is similar to a power bar surge control).
Posted By: mwc Re: Amp problem? - 12/17/03 01:25 PM
In reply to:

First off, is there a reason you feel the need to touch the amp after it is turned on?



You know....it's just the way that some of the buttons and knobs seem to just want to tease you the way they just stand so erect and ridged and its hard to resist running your fingers across the vent sluts....er,uh.... I mean slots and the warmth coming from within and when the power meters begin to dance they just call out to me and I'm attracted like a moth to flame and IT JUST BEGS TO BE CARESSED. But I digress.

Besides, I have to manually turn up/down the volume cause there ain't no' remote.





Posted By: chesseroo Re: Amp problem? - 12/17/03 02:42 PM
My apologies mwc.
I read your original post too fast and skimmed over the word 'intergrated'. The fact that it is an older unit should have also screamed "i have no remote control, i am totally manual".
Yep, that is what this Phillips preamp is like too.
I really cannot stand the manual on/off and volume. I need my remotes.
Other than that i suppose it is a decent unit. I would not have bought one personally, but i'm glad i've got it on loan for use.
Posted By: Saturn Re: Amp problem? - 12/17/03 02:55 PM
lol
Posted By: spiffnme Re: Amp problem? - 12/17/03 04:42 PM
In reply to:

You know....it's just the way that some of the buttons and knobs seem to just want to tease you the way they just stand so erect and ridged and its hard to resist running your fingers across the vent sluts....er,uh.... I mean slots and the warmth coming from within and when the power meters begin to dance they just call out to me and I'm attracted like a moth to flame and IT JUST BEGS TO BE CARESSED. But I digress.




You're just begging for Peter or I to respond to this aren't you? I'll let Peter take this one. I'll get the next.

Posted By: Haoleb Re: Amp problem? - 12/17/03 04:50 PM
fine equipment begs to be touched... when i was in the hifi shop i was afraid to touch the B&W's they had with the guy standing there. but i wanted to oh so bad. And that big Mcintosh with the two big blue radiating power meters. oh the beauty.

That Mcintosh and those speakers, and the shanling cdp they had are some of the most beautifull gear ever made i believe. truly fine peices of equipment.
Posted By: mwc Re: Amp problem? - 12/17/03 06:13 PM
YEEEAH!!!!!!
Posted By: mwc Re: Amp problem? - 12/17/03 09:08 PM
I have a two prong "cheater" plug on the surge protector that pluged into the wall. I'll get rid of it and see what happens.
Posted By: pmbuko Re: Amp problem? - 12/18/03 12:59 AM
I got 'yer prong right here!. Oh, uh, am I too late?

Sorry, I took the day off work to go see LoTR:RoTK. Absolutely amazing!!! (other than the fact that the right-front channel repeatedly cut in and out during the climax. )
Posted By: spiffnme Re: Amp problem? - 12/18/03 01:07 AM
I had some serious issues with the presentation I saw as well. (And it's my literally my job to be fussy.)

1) Numerous complete sound drop outs.

2) Likewise, the theatre I was in had something wrong with it's front right channel as well. (Though it sounded more like a surround channel than a main channel. It got all rattly/staticky during peak sounds - particularly when the score swelled.)

3) At least half a dozen really bad splices in the picture.

4) Lastly, not sure if it was a bad edit, or if they had damaged the print and had to snip out the damaged area, but when Frodo starts running up Mount Doom to toss the ring, Samwise is at the bottom and yells up to him. The next cut, they're both in the mountain. Very abrubt. Didn't seem right. I suspect it was a piece of damaged film that was cut out. ???

With all of that, this was still the most enjoyable movie experience I've had in a long, long time!


Posted By: pmbuko Re: Amp problem? - 12/18/03 01:11 AM
Any tears? Be honest, now.

I was able to squeeze off some cheek irrigation once or twice -- I occasionally allow myself to become emotionally invested if the movie is deserving.
Posted By: spiffnme Re: Amp problem? - 12/18/03 01:13 AM
Close, but I'm too much of a manly man to cry at most movies.
Posted By: mwc Re: Amp problem? - 12/18/03 05:21 AM
In reply to:

(other than the fact that the right-front channel repeatedly cut in and out during the climax. )



It's crap like this that keeps me out of movie theaters. It seems like every time I go, if it's not some idiot that brought an irritable/excitable toddler to the movie (see note below), it's some technical sound/video problem. We have to pay way too much to put up with it.

note: I really do love kids. My beef is really with the parents that bring them.

Hey Peter/Craig, I'm trying to get my amp fixed here on this thread and you guys are talking about weeping.....what the!!! How bout' you guys go cry on someone else's thread(or their beer).
Posted By: pmbuko Re: Amp problem? - 12/18/03 06:10 AM
Hey, if I cried into your beer, then accidentally knocked it over onto your precioussssss-ly touchable amp, would you cry, too?

Remember that it's not nice to punch someone who's already crying.
Posted By: mwc Re: Amp problem? - 12/18/03 06:50 AM
[would you cry, too?]

Would this senario take place at my party? If so, then yes I would because (drum roll please) "it's my party and I'll cry if I want to".
Posted By: Ken.C Re: Amp problem? - 12/18/03 06:53 AM
I'm sorry, I'm afraid you have to leave now.
Posted By: JasonG Re: Amp problem? - 12/18/03 01:44 PM
It takes a big man to cry in public. It takes an even bigger man to make fun of that man.

You guys are reminding me why I stopped going to the movie theater. Y'all need projectors.
Posted By: Haoleb Re: Amp problem? - 12/18/03 03:44 PM
well the last time i was at the theater, watched Pirates of yada yada and they didnt even have the surround on... the theater we usually go to has been consistetly decent except for the people that are also wathing it are usually annoying. either someone who talks or ask's questions or laughs at stuff that aint funny etc.
Posted By: pmbuko Re: Amp problem? - 12/18/03 06:01 PM
The only problem with replacing the movie theater with a home projector is you also need a lot of patience.

I couldn't possibly wait for the movie to come out on DVD.
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