Hum from both speakers...This is New Please read.


Hi All, I would like to say I am new to channel after a long recovery from mid-fi! I am building a system in my home office. It consists of; Jolida 302crc (new tubes tried ), Jolida glass FX Dac, Jolida jd9, Rotel 2500 turntable..., pioneer elite pd65. Monitor Audio Silver RX2, Epos M Sub.
AQ rocket 88 speaker cable, AQ IC's.

So, the Jolida 302 is new. Since the first setup there has been a hum from both speakers. For the last month, I have been going insane throwing time and money at the problem. I have read, I think, every post on audiogon bout hum and the related links connected to other sites.

So, this AM, I am chasing the problem again, and I noticed that when I disconnect the negative speaker connection on the right speaker it goes away. Dead silent. Plug it back in and It returns. If I do this on the left speaker, it does not go away. Thes are biwired speakers and the hum only goes away on the right speaker, negative, low Freq posts. If I switch speaker sides, hum is still there but removing the right negative does nothing.

So,

Is it the negative speaker post on the amp?
Is it the negative speaker post on the speaker?
Is it the cable?

Could the ground in the amp or the speaker be loose on the right neg. post?

I know this subject has been beaten to death, but I think I am going to need counseling if I don't solve this.

Thanks in advance,

Troy
plosive
You don't say what type of interconnects you have. I had a problem similar with WBT's, they can be hard to get to affix correctly. That caused and when tightened ended a hum. Hope this helps
Bananas at both ends. Sub bare wire at amp to spades on sub hi pass

Thanks!
Is it the negative speaker post on the amp?
Is it the negative speaker post on the speaker?
Is it the cable?

This should not be too hard to figure out. You have several components that can be the problem. If you isolate each component to verify it is OK, you will narrow things down until you are left with the problem.

Start with the speakers. Switch them from right to left. If the problem doesn't move with them, the speakers are OK.

Now, do the same exact thing with the speaker cables. Again, if the problem stays the same, you have now eliminated both the speaker and speaker cables.

**I just noticed something in your post. You don't say if the problem occurs with just one or both your sources. Unless you say otherwise, I will assume both and that will rule out all source components and cables. ****

Now go to the amp. I know you have tried new tubes. Try this anyway: Turn the amp off and move the tubes from the right channel to the left and from the left to the right---do all of them, not just the power tubes. If the problem follows the tubes, you have the problem.

Unplug your subwoofer and remove the IC. If the noise is still there, I would have to say that there is some type of internal issue in your amp. But first..

Completely disconnect 1 of your sources (TT, phono pre, interconnects and powercords or Transport, Dac, interconnects and power cords). If after completely disconnecting one of your sources the noise is still there, hook it all back up and unhook the other source.

If the noise is still there after checking both sources, my best guess would be something in your amp or your AC. If you can, try the amp in a different location. If the problem follows one of your sources, you should be good enough at this by now to keep going and isolate the problem.

Also, I'm not a repair person of any kind and could have very well overlooked something. Check all the other posts as they may have thought of something I missed.
Blk25, Thanks! I have gone through the above steps and I'm leaning towards the AMP. Nothing else changes the hum. The right negative changes on the speaker are the only way I can make it stop. ( On both speakers ) and switching the speakers lends the same results. So, the question I have now before me is.. Do I open up the AMP and have a look at the wiring (Grounds to the speaker Posts ) or Pack it up and live without an AMP for ~two weeks, I would think. Really a drag. With the new tubes in, it sounds awesome, but I can not live with the hum ( Knowing it is there kills me! )

Thanks for all the help!
When you solve this one let me know. I have an identical problem with one of my amps. And it is the amp! And it has something to do with the amps grounding scheme. This came up a few years ago when I was trying to use it and I researched it. I believe there is a devise which can be inserted between the preamp and amp input/output to remove this hum. I was first alerted to this possibility by an amp designer. I did the research on Google but unfortunately did not keep the references and the specifics nor do I remember them, but it is there. I never pursued this but from what I read it sounded as if it would/could work. I just started using a different amp.

Good luck