Try eliminating the power conditioner. I've never met one that hasn't caused some problem or other |
Which power cord should I upgrade? The Pre? My TT has its own PSU. I did find that if I did not have the TT PSU plugged into the swithced outlet on my pre the hum diminished somewhat. It (TT PSU) is now plugged directly into a wall outlet. This may be as good as it gets since I can not locate my equipment from ther current locale. |
Then you might be back to trying an upgraded power cord. |
I am pretty sure the hum is caused by EMI since I get it with table power off - just not sure which source is the culprit right now. All my equipment is plugged into a Rotel RLC-1040 power conditioner. With table off, amp & pre on, when I turn volume to 50% I can hear teh hum through each speaker which tells me the cartridge is picking up some interference. |
Try also different combinations of where things are plugged in. Most amps/preamps if the are separate units like to be plugged into the same source to prevent ground loop hum. Try that or try plugging the TT into a different outlet, even try running a long extension cord from another circuit just to test it. |
It definitely has to do with the cartridge/phono section. With all power off accept the pre/amp and phono chosen, I get the hum when volume is turned up. I move the arm over and place stylus on an LP (not running), the hum is still there (thought activating the magnets in the cartridge might stop hum). I'll try placing the DVR cable box between amp & pre. |
Hello Miner42:
If you upgrade the power cord start with the preamp. Do you have a local dealer? They should lend you a cord or 2 to try, hopefully ones that are broken-in. You would hear immediately if it makes a difference or not with the hum. Whether or not it helps the hum it should improve your overall sound especially if you're using a stock cord now. Then the can of worms if officially open. Power conditioner? Upgraded power outlet in the wall. Dedicated circuits. Nuclear reactor in the basement.... it's endless. |
Miner42, try moving the pre away from the power, 2.5 inches is not very far, the oak shelf makes no difference. The phono section of the pre is probably right above the power transformer in the amp. |
Headsnappin
My Pre is one shelf above my power amp - a Rotel RB-1092 - about 2.5" from top of power amp to bottom of pre separated by .75" of oak.
Arch7,
If I were to upgrade my power cord should I upgrade the pre or the amp power cord? The power cord to my TT PSU is not detachable.
Thanks to all who have submitted their opinion. |
Hello Miner42:
I had a P3 that had the same problem. Rega's response was the same. When the LP is playing there is much less hum. I was using a Jolida JD-9 phone stage (tubes) and I found with an upgraded power cord (LAT International AC-2) the hum was much less. I also noticed that once I gave up on trying to get rid of it, it mostly went away. Perhaps one of those audio mysteries like cable break-in. Once everything settled in it was much better. I'm using a Rega RB1000 arm on an LP12 with a Graham Slee Reflex phone pre and it's dead quiet. Maybe the upgraded cables in the RB1000 make a difference or maybe it's the preamp.
Have a little patience and perhaps it will improve. |
How far away is the pre from the power? The preamp phono section could be picking up hum from a nearby transformer. |
Any other ideas? I have plugged the TT PSU into the wall outlet - no change, still hums. I am looking for dead silence when phono is selected on my pre (Rotel RC-1090) and no LP playing. This is when I notice the hum the most. I am at my wits end. Am I asking too much for silence through the phono stage? I am using a MM cartridge. |
All RCAs were tight - no lamp on nearby but I do have a ceiling light that is on a dimmer switch. Light was not on though during play. By internal ground I mean that is the way the Regas are designed. There is an internal ground wire within the tonearm and I believed grounded to one of the RCAs. I was told by the Rega US distrubutor that there will be some hum until the coils in the cartridge are put to use (when stylus sets down on LP). Maybe I am being too anal about my vinyl rig. He also suggested unplugging TT PSU from power conditioner and plugging directly into the wall. I don't like that idea.
How would I externally ground a rega table? |
Do you have a lamp or other non-audio electrical device turned on nearby? My P25 only hum when I turn on the nearby lamp (not on the same circuit) to change records.
Just a thought. |
line the bottom of tt with aluminum foil |
By grounded internally, do you mean via the interconnect and/or power cord? If so, try a cheater plug and also check the RCAs to make sure they are not loose or otherwise not making a good connection = ground. If neither of those work, I would try an external ground to a screw or post on your pre. |
No, not added recently (8 yrs ago it was added). I have had the TT now for 1 yr and this was this first issue (other than location issue when firt purchased) I have had with hum. I am looking for a dead silent background. Hum does not occur with any other sources (CD & iPod). |
If you have recently added a cable TV/coax connection somewhere in the house, try disconnecting it. If that fixes it you need a ground isolation transformer at the coax line. |
