[mr_slacker]

This concerns my stereo amplifier but I thought I could use the immense knowledge of the Head-Fi community non the less.

Today I noticed a hiss coming from my left speaker. It's barely audible at low/mid volume levels but increasing the volume to mid/high levels makes the hiss extremly annoying.

The hiss is present on all inputs. Reversing the left/right speaker connections moves the hiss to the right speaker, so the speakers are OK.

Now the strange thing. The hiss is even present on the headphone out so I guess the amp output stage is alright.

Right now I'm totally confused regarding this...

Any help would be greatly appreciated.

 

[ppl]

Most often the Headphone output of a Receiver and Intergrated amp are taken from the power Amps output just like the speakers however a series resistor is inserted inline to reduce the power delivered to the Headphones so an amp that hisses on speakers will probaly also his on headphones i think you should have your amp serviced

 

[TonyTripleA]

You might like to try a couple of simple things first and report back.

- Did you do the obvious (sorry for asking) and check if the hiss is still there when you select different sources?

- Did you disconnect all inputs and listen for hiss again?

Sometimes the simple things allude us... but if its still hissing its starting to sound expensive!

Cheers,

TonyAAA

 

[mr_slacker]

There's something strange going on here...

I listened (again) to all inputs. The hiss was present on all of them. I have a cd player, soundcard and a dvd-player connected to my amp. The hiss was slightly less on the cd input.

I disconnected everything connected to the amp. The hiss was still there, now equally loud on all channels.

Connected everything again. Listened. On the inputs were the cd player and dvd was connected to, the hiss was almost gone! Not completely gone but acceptable on normal listening levels. On the three others (soundcard and two empty inputs) the hiss was still there as strong as ever.

 

[TonyTripleA]

Hmmm. Now we know something... if the hiss is still there will all inputs disconnected you must have something wrong in the amp or the amps powersupply.

I wonder if you might benefit from checking the earth... just a thought, but are you sure you are effectively earthing. Can you check the power leads earth connection in the amp? Could the cord have been pulled and the earth yanked loose or is it a detachable cable?

Cheers, and good luck on this one,

TonyAAA

 

[mr_slacker]

It's not a detatcheble power cord. And it doesn't carry any earth. Normal swedish power outlets are non-earthed (of course power outlets in kitchens etc are earthed).

I've checked the insides of the amp and nothing seems lose. Since I don't have a circuit diagram I just don't know where to begin. I thought I might go on wild goose chase and change the few IC's that are present in the amp until I noticed that they were soldered to the board.

Guess this is the end of the road. The hiss on the cd input is minimal. I hardly even hear it when the volume is at "this is the maximum level you can play music without getting evicted" level and no music playing. (Did the last sentence make sence?

)

Perhaps this is the gods way of saying that I should upgarde my stereo system...