Stereo troubles - Help please !

[camtheman]

Hi guys, hoping that there are a few stereo buffs out there who might like to lend a hand. .

I have a pretty high powered marantz stereo. Im not totally stupid when it comes to technology, but ive never had this problem before.

It was getting a huge workout last night (Girlfriends 18th) and after about 4 hours of about 5/8ths capacity, the treble just cut out on all speakers.

So the music sounded terrible so it got turned down, and then we all went out after, it got turned off and forgotton.

I turned it back on this morning, and one the four speakers treble is working, but the rest only the mids and bass. So it doesnt sound so good. There is no distortion or rattling sound AT ALL !.

I had 2 fans on it all night, one going into the vents at the back, one pushing air right into the vents on the top of the stereo, and it seemed pretty cool all night.

I was sort of hoping that there is some kind of fuse that blows when there amp cant take shit anymore, and its an easy + quick fix. The replacement value of the the system is about 8 grand, so if youve got bad news, warn me before you say it :rolleyes:.

So a quick re-cap
1. Loud music for about 4 hours.
2. Two fans on it all night (Into vents, keeping it reasonably cool).
3. Treble suddenly cuts out on all speakers, all at once.
4. Tested stereo this morning, treble comming out of only ONE of the four speakers. That one speaker sounds great !
5. I die if ive fucked it up :).

I dont want to fix this myself by any means, I will take it into a shop to get it fixed, but I want to have a feel of what might have happened to it so I dont get ripped off / can prepare for a harsh bill.

Thanks heaps farkiners.
Cam.

[exvitermini]

cant really help to much with the big problem but on the cooling side of things your better off having air blowing into the back and a reverse fan sucking it out of the top.. or no fan at all on the top..

my Denon amp just cuts out(resets as soon as its turned back on) when things are getting to much for it but that rarely happens unless its a stinker of a day..

[camtheman]

cant really help to much with the big problem but on the cooling side of things your better off having air blowing into the back and a reverse fan sucking it out of the top.. or no fan at all on the top..

my Denon amp just cuts out(resets as soon as its turned back on) when things are getting to much for it but that rarely happens unless its a stinker of a day..

Yeah, its a pretty well ventilated stereo, so the fan on the top was pushing cold air in and the hot air out of the other vents. I know its not a pure science, but I figured with all that cool air going in and the hot air coming out, it was doing more good than bad. I don't think this is the focus of the problem at all tho (whether it was a stupid idea or not).

I was also hoping that it would reset as soon as i turned it back on this morning, but it didn't.

Keep the ideas coming :)

[Hex515]

I'm pretty sure you have probably only blow the tweeters in the speaker boxes (the speakers which play high frequencies) or you may have blow the crossovers in the speakers - both are replacable at a cost. I don't think you could have damaged the amplifier if one of the speakers still works. However I would advise seeking proffessional help as I could be wrong. Maybe see the shop you bought the unit from originally? (You've probably already thought about this though.)

Was the music distorting or "clipping" throughout the night? .. I seem to remember reading someone that if tweeters are run clipping they can blow easily.

[camtheman]

I'm pretty sure you have probably only blow the tweeters in the speaker boxes (the speakers which play high frequencies) or you may have blow the crossovers in the speakers - both are replacable at a cost. I don't think you could have damaged the amplifier if one of the speakers still works. However I would advise seeking proffessional help as I could be wrong. Maybe see the shop you bought the unit from originally? (You've probably already thought about this though.)

Was the music distorting or "clipping" throughout the night? .. I seem to remember reading someone that if tweeters are run clipping they can blow easily.

Hey man, thanks for your help. .

There was no distortion at all. I dont know what clipping is, but the music played 100% fine all night (up until they fucked up), and im really thingy about sound quality so i can tell when something is up. Just all of a sudden, the treble turned off / cut out on all the speakers. It was def on all of the speakers cause i took time to check. So the fact that one has come back on makes me think that it is an amp problem (cause speakers dont blow then un blow).

Cam.

[LordNikon]

Simple test.

Switch the channels on the amp, so take the speaker that is working and wire it to the channel that currently isn't working and vice versa. This way you will be able to isolate the amp or the speakers.

It is possible that it's the amp depending on the type of amplification your particular model does. My Onkyo for example has 5 separate amps built into it. So what it does is, takes the input signal, processes it into 5 streams and then amplifies each of those streams and sends the amplified signal to the speakers. Most cheaper amps will do the opposite because it's cheaper to manufacture them like this.

First thing is to do the test and isolate where the problem is though, then take it directly to a technician to fix it.

Good luck.

[camtheman]

Simple test.

Switch the channels on the amp, so take the speaker that is working and wire it to the channel that currently isn't working and vice versa. This way you will be able to isolate the amp or the speakers.

It is possible that it's the amp depending on the type of amplification your particular model does. My Onkyo for example has 5 separate amps built into it. So what it does is, takes the input signal, processes it into 5 streams and then amplifies each of those streams and sends the amplified signal to the speakers. Most cheaper amps will do the opposite because it's cheaper to manufacture them like this.

First thing is to do the test and isolate where the problem is though, then take it directly to a technician to fix it.

Good luck.

Thanks very much for your help dude.
I was thinking about this while I was lying in bed last night, but it was too late to test it because everyone was asleep.

First I tested the input, so i changed it from cd deck to radio and used different cords. . No difference.

Then disconnected a speaker that wasnt working properly, and put it into the channel that was putting out the good music. The music no longer came out good.

It is a speaker problem. Must have blown 3 tweeters and maybe even some mid ranges aswell now I listen to it.

Oh well, off to the speaker hospital or something similar to get them fixed.

[Hitman89]

Clipping is when the amp delivers uneven power that can peak up to double if not more the WRMS output of the Amp. The speaker sudenly finds itself getting 500watts when they can only handle 100watts.

When an AMp is put under presure it starts to clip. A good amp won't blow sepakers but a less powerful one will.

What speakers are they? what are the specs of your Amp? can you give us a model number?

[sawtell]

Even through you have found the problem..
Any way, my Marantz through my klipsch speakers does the same thing when pumping to loud with full bass for to long. i Have to turn it off, turn it on, change the input around (FM, Aux, tape,) then back to the originial one and it works again . .. . most of the time!


It scared the shit out of me when it first happened.

good luck with getting it repaired!

[Hitman89]

Even through you have found the problem..

Isn't it important to understand why it happened not just what happened so it doesn't happen again. If an amp turns itself off its a safety mecanism so it doesn't fry. Trying to trick it into keeping running is a very bad idea!!