Hey Ned, keep it on the topic or go back to your Walkman. |
I agree with Cornfed Boy that if indeed it is a Ground Loon you must shoot it before it mutates into human form. However, it could also be a Systemic Snipe, in which case you will need to have a Snipe Hunt...and there ought to be plenty of advice on this forum to lead you to Infinity and Beyond. |
Hum is the level on both channels. What use alligator clips and wire to short? and which ones are 2 and 3? I think it's time to call my dealer and let him help. Thanks for all the comments!!! |
Hum should probably get quite a bit louder without your preamp or source attached. Is the hum out of both channels? Can you jump pins 2 & 3 on your amps input? If you still get a hum, I would send it back to Victor and the boys at BAT. |
Ok Jtinn, some progress. I lifted the ground on the vk60 with a cheater plug. No change. Used a extension cord and plugged into a different circuit, with/with out cheater plug. No change. On a whim, I pulled the interconnects from preamp to amp. Hum doubled or tripled. Seems like it is in my amp now. Bad tubes? Old tubes? Something else in the amp? I've had the amp for just over a year now.
Thanks |
I have had an incredible hum caused by my cable connection. (as in Cable TV) |
Jfrech: i think ya got it right in the title of your thread. it is a "ground loon" ( runnerup state bird of minnesota, after the mosquito). only thing to do is shoot it. |
Your problem is definitely not with the BAT equipment. It is most probably a ground loop. I had to put a cheater on one of my BAT amps and it solved it immediately. The BAT preamp and amp that you own are DEAD QUIET. All of your cables are excellent and should not be a problem.
Just in case you do not know what a cheater plug is, it is an adapter that has a female side that allows you to attach a three prong plug from your power cord, while the male side goes out with two prongs. It is also known as "floating the ground". They are somewhere around a buck to buy. Get a few of them as they are good to have around the house.
Let us know how well it works. |
Thanks everyone for your advice. I did recently add video equipment. I'll start unplugging that first, then moving the cords around, I do have everything at 90 degree angles and about inch away from each other. If that doesn't do it, sounds like it's time to go from the amp backwards...THANKS!!! |
Ok, Njonker and Jmc have good advice. Try lifting the ground (use a cheater plug) on the amp and then the preamp, but my guess is that wont do it, because I dont think you have a grounding problem. I have tube preamps that in combination with other equipment put out the same kind of hum. Now my stuff is not as expensive as yours and it surprises me that a Bat combo would, but it may be something else in or adjacent to the system. I have a vintage Luxman tuner that just plugged in, not even connected or turned on, will produce a hum through my system. (Anyone want to buy it?) In my second system I have an inexpensive Anthem preamp that in combination with my old Muse 100 amp puts put the same low level hum, and some people say it does the same with the Anthem amp, but its perfectly silent with any other amp I hook it up to. And the little Muse is quiet with any non-tube preamp. Not a good combination. You might also try plugging the preamp into a different circuit altogether if you can. Use an extension cord just to see if that eliminates the hum.
Then, how long have you owned it? If you bought new, have you talked to your dealer? |
You don't have anything hooked up to it that touches a cable line do you. No video souce whatever. I found out that anytime I connect any video device, even a DVD player to a tubed preamp I got a ground loop hum. I tried the Mondial magic box and floating grounds on all different pieces. It improved but the only way to totally eliminate it was unplug the video device from the back of the preamp or switch to a solid state preamp. I know many of you will be dissapointed to learn that I finally chose the latter. If no video source touches your preamp, I don't know, but you could try floating the grounds. |
My suggestion would be to go work from the speaker backwards. Disconnect everything but your speaker and power amp, short your power amp inputs. If your hum is still there, it's the power amp. Try lifting ground in that case. Work your way back through pre-amp and source.
A note of caution here; there is a reason why this stuff is grounded, it is for your safety, so be careful. |
Thanks Paulwp, I have a Bat VK50SE and a Bat VK60. Electraglide AC cords and Transparent and cardas interconnects. Hum occurs with any source. It's not very loud and doesn't change with volume control. I can't hear it from my listening position, but can within 4 feet or so... |
Maybe you do, maybe you dont. How loud is it? First, make sure your interconnects are all on tight, then try a cheater plug. Then move the cables around. Im not sure exactly about the cables but I am sure someone will respond with how to do that. Then, tell us what preamp and amp you have. Lots of them alone or in combination produce a low level 60 hz hum/buzz audible close up but usually not at the listener's chair. Good luck. |
