Farty noise at low volume - EBS TD650 [SOLVED]

[Marsik]

Hi guys,

I'm a proud owner of an EBS TD650. I don't know the year of production but it's older than 5 for sure.

Last time when I was playing at home I noticed something that disturbed me. When I was playing quiently I noticed a distorted farty sound, especially when twitters were turned on... I use a pair of brand new Aguilar DB112 cabs.

I levelled gain properly. I even tried to roll the gain knob back but it didn't help. At high volume the distorted sound is not noticeable. When I roll the gain up the distorted sound became more noticeable, although the led didn't clip. Another thing is that when I plug my instrument into the amp I can hear a noisy rustle, though it's on standby... I checked all my instruments, cables and they're fully functional.

Have you ever heard about the same problem? Any solution?

Cheers!

Edited May 10, 2017 by Marsik

[mrtcat]

HD350s used to suffer from a background distortion caused by an earth problem (something to do with the control knobs) that was only noticeable at low volume. It was still there at gig volume but was masked by the main clean sound as it got louder.

[Marsik]

Thanks for the response. May it have bad impact on speakers' condition? I'm afraid of it.

[bassjim]

I had this on an old 4ohm version of a HD350. Took the lid off, got at the boards with a soldering iron, went over the solder joints where ever possible and gave it a general clean up. Dont know exactly what that did but it fixed it for a bit.... but then the problem came back. Ended up selling it and got a replacment HD350 2 ohm. (still have and love).

To be fair the old 4 ohm job had done the rounds, I was the ump-tinth owner with no real knowledge of what may have happened to it other than a dent in the chassis, so all in all it had served well to many for many years.

If you can get some electronic wizz to have a look could be worth a punt but I think some things will eventually give out.

[Marsik]

Thanks bassjim for your message!

I should definitely go to a whizz for help but as you know it's the Christmas Time so I can't afford it.

I looked for a similar problem on the internet and here's what I found:

[quote]EBS told me to replace them (or send the amp back to EBS so they can replace them) or use a non-lubricant cleaning solvent to clean the contacts. The sound described in the first post is the exact description of the sound I get when the jacks aren't properly put in the effects loop or tuner out.[/quote]

Edited December 15, 2016 by Marsik

[EBS_freak]

To see if it's the old fx loop problem (which was later fixed) put a jumper cable between the send and return on the fx loop on the rear. This may solve the problem. As stated, some servisol sometimes solves the problems but a new fx loop board would be the fix if you wanted it to be A1.

[Marsik]

Hi guys!

I'm so sorry I haven't written for sooo long. I feel like I owe you an explanation. Finally, I fixed all the problems!

Well, I sent my amp to an electric engineer. He checked the amp and here's how he fixed it. He cleaned all connectors and synch the power amp - I don't know how to explain it in English. The problem with standby was caused because the phantom button on the effects loop was pushed. I don't use any effect. That's why I always noticed bang when plugged a cable.

Hope, it's helpful.

Best regards