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Need some help with an amp.

Once again, I need some information/help. I just got an Aragon 2004 from ebay. I am getting some humming/buzzing from the speakers. It is louder from the left speaker than it is from the right.

I disconnected everything, unplugged everything except the amp and the left the speakers connected and I'm still getting a hum. So, I plugged everything back in.

Now, for some observations.

1. Everything was plugged in and connected. My preamp was in standby. The switch on the amp was off. I unplugged the interconnects from the amp, so that amp is sitting there, plugged in with the speakers connected with the switch off and nothing hooked up to it in terms of interconnects. I grabbed an interconnect and got a loud hum from one of the speakers. The only thing that the interconnect was connected to was the preamp (NOT the amp).

2. I went to plug the interconnects back into the amp. The preamp is still in standby and the switch on the amp is off. With one of the interconnect plugs in my hand, I was reaching behind the amp to plug it in, my bare arm touched the amp and I got a little shock. Not a big one, but I can definitely feel a small current.

3. With the preamp in standby and the switch on the amp off and the interconnects disconnected from the amp, I touched my bare arm on the case of the amp and grabbed the connector on the interconnect with my other hand and felt the "shock" on my bare arm.

Can anyone tell me what's up?

Thanks.
tonyangel
magfan
1,583 posts
 
Sounds like the IC is acting like an antenna, no?

Are their any 110 wires up/down the wall behind where you are running the IC?

I have lots of BJC without defect. See if you can borrow some ICs from a store to troubleshoot, though I'm doubting the defective cable idea.

Any way to run this as balanced? The MkII version has balanced in, so you'll need a balanced out pre.

The original seller should kick down half the repair costs.....at least. Send him a copy of the bill with a nice note.
hifihvn
943 posts
 
Be careful about plugging in the ICs to the amp only. If you touch/bump the center pin on the RCA, it could wipe out your speakers. Getting back to the long ICs, it could be the design, or a defect. Maybe some with better shielding would work. It sounds like you might be getting some AC hum through them. Don't get any braided type like Kimber braided. Get something that is more of a coaxial cable type. Also, buy from a place that allows trials. Before trying new ones try rerouting present ones, and try to keep them away from the power cords, especially parallel runs. Also, see if you could reverse (polarity, rotate AC plug in outlet) any AC plugs, if it could be done.
hifihvn
943 posts
 
I'm slow. Magfan's post appeared while I was doing mine. Same idea, except I forgot to ask about the balanced cable idea.
tonyangel OP
309 posts
 
I don't have balanced outputs on my pre nor balanced inputs on my amp, but I did order another IC to try out.

I also emailed the seller. He's giving me the silent treatment.
swampwalker's avatar
swampwalker
5,138 posts
 
If you have to put your ear up to the speaker to hear a slight buzz or hum, I would say that it's not an issue. However, if the seller does not respond soon, I would open a dispute w Audiogon (if they still allow them, otherwise I would post negative feedback, if they still allow that).
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