Please, help identify thump sound

[tp]

Hi all,
my father-in-law is getting a thump,thump,thump sound 1 to 2 times in a song and then may not here it again for like 3 songs later. now, let me explain when he is getting this. it is happening ONLY when he records a vinal to cassette tape,its only coming out on the play back of the tape. he will not here it while the record is being played,but again, its coming out on the tape when played back.
weve tried replacing one component at a time, then all components at once. its still there on recordings. items we tried to replace are , record layer,reciever,tape deck, all new wires except speaker wire,which at least looks to be fine. nothing has changed at all when problem started.
what could be causing this ???? it it the electric?? some piece of equiptment in the house or maybe a nieghbors?? he does have the socket overloaded and has a cheesy multi plug in outlet type box.
Help??
thank you
Tim

[E-Stat]

Hi all,
my father-in-law is getting a thump,thump,thump sound 1 to 2 times in a song and then may not here it again for like 3 songs later. now, let me explain when he is getting this. it is happening ONLY when he records a vinal to cassette tape,its only coming out on the play back of the tape. he will not here it while the record is being played,but again, its coming out on the tape when played back.
weve tried replacing one component at a time, then all components at once. its still there on recordings. items we tried to replace are , record layer,reciever,tape deck, all new wires except speaker wire,which at least looks to be fine. nothing has changed at all when problem started.
what could be causing this ???? it it the electric?? some piece of equiptment in the house or maybe a nieghbors?? he does have the socket overloaded and has a cheesy multi plug in outlet type box.
Help??
thank you
Tim

Good question, Tim. If you hear a thump consistently at the same point in the tape on multiple machines, it sure sounds like that has been recorded on the tape. If the tape player does not thump with pre-recorded tapes, then it would seem that the player is fine.

Shorted interconnects could be responsible, yet you say you have switched out both pairs of cables going to the tape unit. You might try moving it to anther room where you can locate a socket that is not "overloaded".

rw

[Mr Peabody]

Interesting problem. I don't see how a sound could get onto the tape without being heard while recording. Especially if it happened on 2 different tape decks. Even if it was the wiring, I would think you should hear the sound as it happens. What kind of equipment are you using? Is it possible that the tape head is picking up sounds that aren't being heard while recording? You'd have to have a pretty bad phono preamp for that to happen. What is the equipment near? It could be static discharge but I wouldn't think that to be more than one pop. I'd try what Estat suggested and move the stuff into another room to see if you have the same phenomenon. Does the music drop out while the thump happens or do you hear both simultaneously?