Buzz sound on DENON Amplifier

[Bandula Chandranath]

I have fairly old DENON UTP-250 Pre-Amplifier and UPO-250 Power Amplifier. I have connected CD-Player to CD Input, iPod to TAPE in via Airport Express. system worked fine. I use mostly iPOD to play music. one day while try to play a song system stooped giving me loud noise. thereafter gives me annoying buzz at 0 volume also each time i try to play. Pre-Amplifier section has power inputs for other devices those i used to give power to CD-Player and Plate player. after that incidents Power sources did not work anymore.(this is not a problem because i can hook up other devices directly).system works as it was before but annoying noise still exists on when I switch to TAPE mode where i hooked up iPOD. can anyone suggest me what went wrong and why it gave me annoying buzz at 0 volume ?. I am still thinking of repairing the Pre-Amp. what cause sudden loud sound?

 

[americanaudiophile]

Do you get the noise on the tape input without the Ipod/airport express connected? Try connecting the CD player to the tape input and see if you get the same noise. Problem may be in the source not the preamp. You can also have a grounding problem in the preamp that might cause this. Old capacitors can cause noises too but not usually in one input only.

 

[Bandula Chandranath]

without connecting to tape Input ,i do not get any noise. now i hook up iPOD/Airport Express to DAT input,sound fantastic. when I connect to TAPE input even without connecting any source giving me loud noise. as far as I do not connect any source to TAPE input system works as it should.. sound wired,isn't it?.I opened pre-amp casing and i saw there were 2 fuses and one was blown out. so removed it. Is this symptom cuz of blown fuse?. I do not use pre-amp's switched or unswitched power input to power up other devices now. I am searching correct fuse to be replaced .
what do you mean by grounding? i ddnt get it

 

[americanaudiophile]

A blown fuse wouldn't usually cause noise. Since the AC outlets are not working the fuse could be for those. If there is a marking near the fuse holder to show the value that the fuse should be get that value. The one that blew might be incorrect. Do no use a higher value fuse.
Sometimes when you connect a source to an amp there can be more than one ground connection between them (such as one through the audio cable and another through the AC cord ground connection). If there is it can cause hum and buzzing noises. Doesn't sound like your problem. If you are not inclined to get it repaired you can use it without the tape monitor input.

 

[Bandula Chandranath]

Thx AmericanAudiophile. I'm not inclined to repair it now cuz system works really well now with the DAT input. my only problem I have no Audio in now to hook up my DVD player sometimes i use to play HD Audio. (..