Do you have dimmer switches anywhere in your home? If yes, try turning them off, and see if that makes a difference. That suggestion solved all of my problems last year.
Not a ground loop hum???
I thought I had a ground loop hum, given that with my pre, cdp and amp all on, without any music playing, there is a hum emanating from my speakers. Following the advice seen here and elsewhere, I went out and got some cheater plugs to try and hunt down this annoying and, at times, distracting hum.
My system comprises: Anthem CD-1 (with DH-Labs power cord), Blue Circle BC21.1 tube pre (with BC62 pc), BC22 amp (Zu Cable BoK pc), Rune loudspeakers by Zu Cable (hooked up with Zu Cable Libtec speaker cable), Blue Circle MR1200 balanced power line conditioner/distributor (Zu Cable BoK pc), and van den Hul D102 MKIII interconnents.
Well, with the three components' power cord fitted with a cheater plug and all plugged into the power conditioner, the hum was still present, same intensity, volume, etc. Removing the cheater plugs one by one starting with the cdp, then pre, then amp, there was no reduction in the hum. In fact, I think I may have heard it get worse at one point.
Any ideas out there as to the cause of the hum? Maybe the tubes in the system are the culprit. There is a pair of Siemens CCa (6922 type) with Pearl tube coolers installed in the pre, and the tube in the cdp is a Telefunken CCa with a tube cooler.
My system comprises: Anthem CD-1 (with DH-Labs power cord), Blue Circle BC21.1 tube pre (with BC62 pc), BC22 amp (Zu Cable BoK pc), Rune loudspeakers by Zu Cable (hooked up with Zu Cable Libtec speaker cable), Blue Circle MR1200 balanced power line conditioner/distributor (Zu Cable BoK pc), and van den Hul D102 MKIII interconnents.
Well, with the three components' power cord fitted with a cheater plug and all plugged into the power conditioner, the hum was still present, same intensity, volume, etc. Removing the cheater plugs one by one starting with the cdp, then pre, then amp, there was no reduction in the hum. In fact, I think I may have heard it get worse at one point.
Any ideas out there as to the cause of the hum? Maybe the tubes in the system are the culprit. There is a pair of Siemens CCa (6922 type) with Pearl tube coolers installed in the pre, and the tube in the cdp is a Telefunken CCa with a tube cooler.
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I had sent an e-mail to Blue Circle and the response was as Brooks1 and Sean have indicated. Balanced power outlets will indeed show reversed hot and neutral or other icorrect wiring, because there is 60V coming from the neutral and 60V coming from the hot in relation to ground. Blue Circle insists that it is likely really dirty incoming AC causing mechanical noise in the transformers of the MR1200. I'm back to my question of why bother with this relatively expensive power conditioner to prevent noise in the stereo components only to have the conditioner make noise. I've swtiched over to the $200 Monster HT1000 power bar that was lying around since I received the $750 MR1200. Guess what, no noise from the HT1000. This just ticks me off. Next week we move into our new house, so I'm really eager to see what kind of results I will get from these two units plugged into the dedicated line I had installed. Will the MR1200 continue to hum? Will the Monster piece mash the Blue Circle again? Enquiring minds want to know! FWIW, I'll post my findings in a few days and continue to ponder Chris VenHaus' solution of wiring two 0.47uF 600V Auricaps in parallel in the dedicated outlet if the MR1200 is still noisy. Has anyone out there tried the latter yet? Thanks again to all for your comments and ideas. Max |
Max: The caps won't correct what is a design error or quality control problem with the Blue Circle PLC. If you want to use that and get good results, it needs to be replaced or repaired for proper operation. That is, if this unit doesn't take standard polarity AC and convert it to "balanced" power. I'm not familiar with this specific unit, so i'm adding that as a disclaimer. As mentioned, "balanced power" will play games with polarity sensing devices. As mentioned in another thread, "balanced power" can also undermine the design integrity on some well engineered gear. As such, adding such a "tweak" to your system may actually be detrimental to performance and / or the lifespan of the gear. If you're interested in some alternative points of view on tweaking your AC, try reading the tweaks found on David Magnan's website. As with anything else involving high voltage & current, be careful and use some common sense. It is NOT worth getting injured or killed no matter how much better you think your system will sound after doing something that could be considered "unsafe". Sean > |
Mghcanuck I feel your pain. I have been adding new power lines to my basement and picked up a hum. I rerouted cords. I put magnetic shields on cords. The hum did not subside. Finally, I put a Monster HT1000 on my video cable line which was also new and plugged the cd Player and tuner into it. The result no hum. And do you know what where the worst hum was located? The TV speakers. I'm even thinking of buying a second HT1000 for my main system. It also has Cable and a FM Tuner. |
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