computer to amp causes overload

[shmooglepuss]

Hi, I've been having this problem for awhile, hope someone can shed some light on it. I've got my computer hooked up to an amplifier, I play mp3s through winamp, and the amp will suddenly overload and stop playing. At first I thought it was the amp, so I bought a newer one, same thing happens. Brought over a friend's new amp, same thing. Someone suggested that it might be the volume level on winamp, so I tried it at half volume, and that seemed to do the trick, but no dice. Same thing happened, yet again. Now I'm wondering if it's my soundcard, which is quite old now. Here's all the info I have: Technics SA-AX720 amp, 8812 Linear Phase Studio Monitor speakers, 240 watts, generic soundcard, a couple of years old.
Any help would be greatly appreciated, thanks.

 

[Unregistered]

That's something for the record, for me. An amp often goes into overload and shuts off if it detects a very low impedance at the ouput that requires more current than it can deliver. If instead of this, the input is overloaded, meaning you exceeded the maximum input voltage recommened, the sound is often distorted even at low volume levels. And there'd really be no impetus to listen at all. And since you said even at half volumes the amp is still shutting off, your soundcard must be sending super or ultrasonic signals that are causing some instability with your amplifier's feedback circuitry to cause it to overload. (Reminds me of some old Sansui amp that used excessive a proprietary superfeedforward circuitry in its global feedback loop. Their power transistors would fry at the slightest excessive bass frequency input.)

After all those successive changes in amps with no success, I would suggest it may be good idea to try out another soundcard to see if that's the culprit. I think soundcards are a lot cheaper than amps, don't you?

 

[markw]

Does your sound card have a line level output?

If so, use that. It takes the signal BEFORE the power amp stage, which is much more palatable to a receiver/amps input stages.

 

[shmooglepuss]

I've been fixing the cart instead of the horse?

Thanks, I'll get myself a new soundcard and hope that that helps. It never really occured to me before that it might be the soundcard, I guess I was too focused on the amplifier. It's quite true, cards are cheaper than amps, I guess I've done this backwards so far... anyway, I'll try and find one with the line level output mentioned, and hope that fixes the problem. I'll be back to let you know if it worked.

 

[JoeE SP9]

A Sound Blaster card may be what you are looking for. They all have a line level out and are not overpriced. I have SB cards in all the computers I own and use the line level out to connect to my rig. I have never had a problem.

 

[Kesomir]

soundblaster's digital output on non breakout cards leave a lot to be desired, although that aside the're pretty solid.

Would recommend any AC97 card with decent digital outputs. I use my motherboard's digital outputs for all sound playback and my soundblaster live! 5.1 for teamspeak only.

Of course if you only want analogue it doesn't really matter

 

[shmooglepuss]

new soundcard, same problem

Hello again,
Today I bought a Sound Blaster Audigy 2 ZS card, installed it, connected the amp, started winamp, played great for about 4 songs, then nothing. Overload again! Couldn't believe it... I really hoped the soundcard would do it. Unless maybe I don't have it configured properly, I don't know. I'm about ready to go back to albums on the 'ol turntable...

 

[JoeE SP9]

Would you please be more specific about how you are connecting your PC and amplifier.

 

[shmooglepuss]

connection

It's connected with a 3.5mm to RCA plug adapter out of the soundcard and into the amp.

 

[JoeE SP9]

Have you tried a different input?

 

[Mark Duncan]

Make sure your soundcard is configured properly also. I'm using the SantaCruz Turtle Beach Card, and it has a Versajack that can be configured for analog out or digital out. To run into an RCA input on the amp, it needs to be set to analog. You may have something like this.

Mark

 

[rectifier]

Good question JoeE SP9 - I hope shmooglepuss is plugging into AUX or another line input, as opposed to the (much higher-sensitivity) PHONO inputs of these amplifiers. Otherwise, is there a stray wire shorting one of the speaker leads / are these amps being put somewhere too hot? If "the same thing" has happened to 3 different makes and models of amp, can you define more clearly the symptoms of "overload"ing?

 

[shmooglepuss]

I borrowed a friend's speakers for a party the other night, and everything seemed to work fine. I tentatively started upping the volume over the course of the night, and to my surprise and glee, no overload! So far, that's the only thing that's made a difference, different speakers. I have no idea why that should be...

 

[shmooglepuss]

Sorry, missed a question up there.

I've been plugging into the CD input on the amp, and the soundcard is set to analog. I've also had a fan blowing on it while it's on, thinking that it was overheating that was causing the overload. (Although, it's overloaded and stopped playing sometimes only minutes after it's been turned on and still quite cold, but I thought I'd better cover all my bases anyway.)