Thread: Fizzy or buzz sound in my set up

I just have my keyboard hooked up to my AV Amplifier via the AUX input using an unbalanced TRS jack. When I turn it on and begin to press the keys there is a fizzy or buzz sound off some of them and its more noticeable as I move up the octaves... C5 onwards. It also happens if I press more than 4 keys that are next to each other. Its NOT a faulty audio adapter or the 50/60hz hum from the mains. Just curious as to what might be causing it. Its really easily heard when I press any of the keys between C6 and F6...sharps/flats included. I wonder is something to do with frequencies of the notes and they are making something inside the speaker rattle? faulty speaker? dodgy amp at reproducing the sound? its very its almost like I can also hear some distoration taking place too. Strange.

My guess is it's either something faulty inside the keyboard or maybe at a long shot - is it sitting too close to the speakers or something else that might cause distortion?

Good point, the keyboard is really only an old junker. Not that its a n ancient relic from the 80s like some of my other boards are, but just a cheap ranged one.

More then likley that. I reckon it can't handle the frequency range too well then. Probably could when new but maybe not now if you've had it a while, or in storage or something.

Bar , whos that fat moody fat bloke in your avatar?

if it's not a synth and just a keyboard then it's not designed for that sort of amplification
a synth has 2 individual outputs which are balanced mono L-R designed for the line / instrument input of a mixing desk
im guessing you have plugged the headphone out jack into a amp causing harmonic distortion or even worse ground loop
in the audio path.

Originally Posted by J3D

im guessing you have plugged the headphone out jack into a amp causing harmonic distortion or even worse ground loop
in the audio path.

Yes mate thats exactly the case here. Would you elaborate on this J3D? Why it happens, effects and problems it causes and so forth. I'd like to know as I'm going into college soon to study Music technology and Sound Engineering and would like some and certainly appreciate any additional info people can throw my way.

Originally Posted by Ray Sparra

Bar , whos that fat moody fat bloke in your avatar?

Thats me, as for fat... mate my last weighing 3 weeks ago was 57.6KG thats around 9st.

well the headphone output has a stereo pre amp assigned to it so basically your plugging a stereo amp into a stereo amp
causing the master volume to overload. The headphones output is not designed for this purpose and the keyboard it's self will have
a maxium output range for stereo headphones.

only way you can solve this problem is by turning the volume down on the keyboard and turning the volume up on your main amp.