Page 1 of 1

60 cycle hum conundrum....

Posted: Mon Jan 29, 2007 6:24 am
by arkjack
I have been trying to mic my amps for guitar and bass tracks. I always have a a nasty 60 cycle buzz hum from the amp and speaker... I switched to different amplifiers on hand and still get the hum... changed sockets... Then I realized that all three of my amps are Fender amps... a Bassman 30, Accoustisonic 30, and stage 20..... I used to have a Fender bass that hummed like crazy because it "is a Fender Jazz Bass and it supposed to hum".... So wondering if anyone out there knows that the Fender's are notoriously hummy and its in the design and i should switch manufacturer to get a studio quiet amp set up.... ArkJack

Re: 60 cycle hum conundrum....

Posted: Mon Jan 29, 2007 11:39 am
by edteja
My Acoustasonic doesn't hum, Jack. But you need to make sure that the electrical outlet is grounded. It's probably your house wiring, not the amps. I am a Fender fan, and even my old 60s Princeton didn't hum. Well, not much. If that isn't the problem, you can usually decouple the hum with a filter cap.

Re: 60 cycle hum conundrum....

Posted: Mon Jan 29, 2007 11:55 am
by ernstinen
Yea, it's a ground problem. A lot of amps have a switch on the back that can help. Also, lifting the ground (using a two prong adapter) sometimes works.Also, florescent lights are notorious for causing hum in amps.If none of these tips work, smashing it with a baseball bat is a possibility. Ern

Re: 60 cycle hum conundrum....

Posted: Mon Jan 29, 2007 12:38 pm
by arkjack
Now that you mention it..... I do remember a time making recordings when the amps didn't hum..... I am wondering about whether the florecent lights upstairs in the kitchen or some other set of lights switched on is what's causing the problem.... sounds like I have a science experiment tonight..... I'll report my findings in the morning....Thanks for the ideas....ArkJack

Re: 60 cycle hum conundrum....

Posted: Mon Jan 29, 2007 12:39 pm
by horacejesse
Quote:Also, florescent lights are notorious for causing hum in amps.What memories. I used to play often in a bar where the stage was lined with flourescent beer signs. God, what a nightmare. The proprieter loved those signs and was really irked everytime we started complaining and asking for them to be turned off. He would never allow them all to be turned off. Nightmare.

Re: 60 cycle hum conundrum....

Posted: Mon Jan 29, 2007 12:53 pm
by ernstinen
Quote:What memories. I used to play often in a bar where the stage was lined with flourescent beer signs. God, what a nightmare. The proprieter loved those signs and was really irked everytime we started complaining and asking for them to be turned off. He would never allow them all to be turned off. Nightmare.Talk about memories --- I was in a band that got a gig in a huge, brand new club in Lansing, MI. There was one (big) problem: The audio snake from the sound booth was run parallel to the light wiring to the stage. Talk about HUM! It was terrible. Whomever did the wiring should have been sued and put out of business. Unforgivable! Ern

Re: 60 cycle hum conundrum....

Posted: Sat Feb 17, 2007 6:35 am
by kouly
I would say it is most likely a ground loop. I had a bad one and had to get a humeliminating filter. The one I got lists for $90 but it goes for $65 online. It is probablybetter that eliminating the ground since that could kill you and that would really ruinyour day. When you look at it like that 65 is not so much to spend. Look at the reviews. Rated 10 out of 10 for Sound with 31 reviewshttp://www.zzounds.com/item--EBTHUMX

Re: 60 cycle hum conundrum....

Posted: Sat Feb 17, 2007 7:22 am
by andreh
You might also try plugging all your electronically coupled devices (meaning they're connected by metal like guitar or MIDI cables) into the same wall outlet (through a power conditioer or surge protector, obviously), so they share a common ground.An alternative to this is directly grounding each device to a common "earth," but this entails putting a rod in your studio and requires some in-depth knowledge of electrcal engineering.Try unplugging different devices in your studio from the wall one at a time (whether they're turned on or not) to see if the problem goes away...if it does, you have a ground loop as Kouly suggests, and you should try his suggestion and/or one of the above.Andre

Re: 60 cycle hum conundrum....

Posted: Sat Feb 17, 2007 8:14 am
by arkjack
I did a lot of experimentation a few weeks agao trying to isolate the sources of the the hum. (root cause analysis). I found a couple of devices and signal chains that produced hum at various levels.... a +b=hum a+c=hum a+ b + c= hum b+c = no hum a was culprit... it was supposed to be a 3 way splitter that took the input and made 3 outs.... the a input is actually a signal I/O and would create the feedback loop that induced the hum... It was basically coming from my desire to track the individual parts simultaneously with different methods.... ie. accoustic guitar track ... channels 1 2 3 4... 1 = dry direct line 2= effected preamp line 3 = small diaphram condenser on 12 fret. 4 = large diaphram condenser on amp.... I been experimenting with layering the different textures of the simultaneous track recordings and liking the results.... gives a lot of lattitude to adjust tone without farting around with too much eq...ArkJack