I would start all over again, unplug everything and have your amp and speaker connected. Short the inputs to you amp so that there will be no external signal introduced to you amp. Turn amp on and listen for the buzz, if the buzz is still there I would think the amp is the problem, if the buzz is gone I would plug each component in one at a time, to find the problem. When you connect cables or do anything with cabling I would not only use your mute or standby switch but I would tune everything off for safety. The voltage difference between equipment is a grounding problem which could be external or internal to one of your components, could be part of the problem but I would start with the sequence that I mentioned. To clarify the above if the amp is with out noise hook the preamp up without any components plug into it check the buzz and continue until you find the problem.
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First of all, let the seller know about the problem. Handle this however you want.
If you have a digital multimeter and know what your doing, you could check the amp and preamp to a known good ground. This would at least tell you where the voltage is coming from.
The hum being louder in one channel doesn't sound normal either IMO.
The voltage being present on the amps cabinet can be dangerous. It could be capacitance somewhere causing it, or something that may have been worked on. Sometimes some amps do have a small voltage on them from moisture if the amp was cool, and can have condensation in them also.
If the amp has a grounded plug, make sure the outlet is properly grounded. If it just has a two prong plug, try reversing it in the outlet, if the prongs (plug) are the same size, allowing the reversal to be done, plugging it in. Check and try the preamp for the same (plug reversal).
If you try reconnecting this equipment, make sure you unplug everything (from outlets) first, before making, or changing any connection. With this voltage difference, if you plug something in and the center pin (RCA) makes contact first, before the outer shield does, it will feed that voltage to the delicate transistors (amp or preamp) and damage them. So be careful with this, and most important, make sure you don't get shocked.
Some amps will hum with nothing plugged in them. A shorting plug (RCA) on the inputs of the amp will prevent this. Some people make their own (the center pin is shorted to the shield), or you can buy some like these in this link.[http://www.mcmelectronics.com/product/27-5335&scode=GS111&CAWELAID=240971936]
Yeah, the whole humming issue is just a minor annoyance that I may have been able to work out, but the current running through the chassis really had me concerned. I really didn't think that it was normal for any sort of current to be running through the chassis. Still, I didn't want to assume anything and thought I'd ask.
I contacted the seller and will give him the opportunity to make this right. Other wise, I'll just go through paypal.
Well, I contacted my local high end shop. The owner is a pretty nice guy. He referred me to a shop that happens to be less than a mile from my office. He tells me that he's been using this guy for 30 years and that he really knows what he's doing.
I'm going to drop the amp off tomorrow and let him take a look at it and see what it needs. If the amp can be fixed for a reasonable cost, I'd really like to keep it.
Thanks for all of the info.
I have the same amp. Assuming yours hasn't been worked on and your safety ground is intact, it should blow a fuse if there's a dead short to chassis. Have you checked your house wires for correct polarity? If the neutral and hot are reversed I could imagine an opportunity for leakage to chassis. Ground loop is also up on my list for causing the hum.
OK guys. I really appreciate all of the words of wisdom and experience. I went and picked up my amp today. I got to talking to the guy, and it turns out that he does all of the repairs for most of the high end shops in my area and is the NAD warranty guy, so I feel pretty confident about his work.
He went through the amp to check things out and make sure that all was in order. He replaced the quad opamp ICs and the coupling caps. The good news is that the hum/buzz got better and it doesn't shock me anymore.
The bad news is that I still have a slight hum/buzz that I can hear when I put my ear next to the speaker. It isn't anything that I can hear from any sort of listening position, even during quiet passages, but it's there nonetheless; and I know its there.
More good news though, when nothing is hooked up to the amp except the speakers, I get dead silence. Due to limited space, I have my amp in an elevated area and it's connected to my preamp by way of a ten foot long IC cable. When I plug the IC cable into the amp (with nothing connected to the other end and it's just dangling) I get the hum/buzz. I think the long IC is picking something up. When I tried the test with a shorter IC, I got dead silence again.
As I said, now I think that the long IC cable is picking something up. I just can't figure out what. Either that, or there's something wrong with the IC. What do you think would be the odds of that? It's from Blue Jeans Cable.
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.
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.
I didn't buy the amp on audiogon. I got it on ebay. Really, the guy didn't have much feedback, but what he had was positive, so I took a chance. The claim was that it was "like new" (exact words) and had been tested. Once I got the amp out of the box, it was clearly NOT like new, with scratches on the chassis and faceplate and rust on the screw heads. I also found out that his "testing" consisted of hooking the amp up to see if it played.
Anyway, the guy did contact me today and the position that he took was that it was working when it left him, so I must have done something to it.
The buzz/hum that I'm hearing now is much less than it was hearing before the repairs and the amp doesn't shock me any more when I touch it while grounded. I'm considering it fixed and I'm the proud owner of a tank of an amp. I really like the way it sounds.
I'm gonna email the guy a copy of the invoice and see what happens.
At least, now, I have an old amp that I've always wanted and that has been gone through and I have peace of mind.
Thanks again everyone.
You must have done 'something' eh? Like what? plugged it in and tried it?
If the seller doesn't at least kick down 1/2 the fix cost, leave some really awful feedback.
I'm sure the testing was 'lights on? check.' followed by 'no smoke? check.'
It's not called EPray for nothing. I'd personally never deal with that site unless I could go check it out firsthand.
Yeah, I know guys. I just let my emotions get the better of me. I've been wanting an Aragon for a while and I don't see too many 2004s for sale. When I saw this one, I snapped it up.
Tpreaves, you are right. Still, I wanted the amp and now I have it and didn't get ripped too badly. On the bright side, I have the amp that I wanted. I got it for around $350 and the additional costs that I paid are going into the peace of mind category, since the amp has now been gone through by someone that I trust.
Of course, the seller took the position that I must have broken it and he isn't helping out, so I'm kind of stuck; but I am sitting here listening to my system and loving it.
Man, I did leave a pretty nasty feedback, but after thinking about it, I retracted it. In truth, I kind of screwed the pooch on this one. Although I think the seller was maybe a little less than honest with regard to the shape of the amp, it is also true that I could have gotten a refund rather than having it fixed.
Getting it fixed was on me, just because I wanted to keep the amp. They're pretty hard to come by.