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Hey guys. I've been getting a crackly hum from my guitar amp. When I start adding compression to the mix the noise shoots through the roof. I've been told that I need to use a power conditioner instead of plugging the amp straight into the wall. Is this correct?

I'm only playing clean tones. Think Motown, old soul, etc. I have a tele, les paul, and a silvertone 1429. I'm using a fender super reverb and an orange thunderverb 200 w/ a 4x12 cab. So far, I have only recorded using the super reverb turned up to about 1.75 out of 10. And I placed a 57 slightly off axis about 1 inch from the best sounding speaker. My guitar tones sound thin and with a lot of hum. As you can see, I need a bit of help here.

How do I eliminate the hum from the amp? And how should I set up the amp/mic?

I would appreciate any feedback!


RemyRAD Sat, 01/21/2012 - 21:52

Many guitars are very sensitive to spurious electromagnetic interference. Sometimes, people will recommend hum bucker pickups but their tonality is quite different. Those flat wound open pickups, pick up all the noise quite well.

When I'm having problems with guitar hum & Buzz, I'll frequently ask the guitarist to "rotate" in their position. Sometimes, that way, you'll find a null, where the hum and/or buzz will greatly reduce. Experiment with your positioning within the room. I actually discovered a power main feed under the floor of a studio with an electric guitar. A raw tape head can also be utilized for that purpose in finding electromagnetic interference. I had to do that when dealing with hum in an NBC production studio where I also located a power mains feed under that floor also with a tape head. I was told there was no power mains feed under the floor. But I found it and there was one. Later, deeply buried hidden diagrams proved I was right. So much for people's memories.

When guys come to record with me, I recommend that they bring small guitar amplifiers. You need big ones for a big venue, no doubt about that. You need small ones for studio use which will generally sound huge. Big rig's never sound huge in the studio. That is unless you jump through all sorts of hoops & microphones. You may also want to build an iso-speaker box for recording purposes. That way you can turn it up to where the sound begins to bloom without disturbing the neighbors and/or family. You want those tubes to saturate. You want the speaker to deliver a tonality you want. Sometimes a highly resistive speaker load can be employed (with proper heat sinking). Commonly referred to as a power soaker. This can improve the recordability of the guitar. There's always a trade-off or compromise to be utilized in getting what you want.

There is also a software that can deal with guitar buzz quite effectively such as Cool Edit 96 and beyond to the latest editions of Adobe Audition, Sound Forage, others. You sample just the buzz in the noise reduction processing section of the software. You then reduce the noise by your selected amount. Utilizing 100% noise reduction frequently adds too many audible artifacts. So it's a trade-off. An educated compromise. Most amplified guitars have some modicum of buzz in them. And any sustaining foot boxes will only make the noise unbearable. Although most of it may be completely unnoticeable when you are playing. This is where noise gates come in and out and in and out, you get the idea. So the guitar microphone is virtually shut off when you aren't playing anything. It only opens above a preset threshold you set. How else do you think we recorded clean guitars back in the day before software? KEPEX, that's how and telling guitarists to rotate. Some of them actually took offense to me asking them to rotate. WTF what offense? Just rotate! Dammit, rotate! No! Do not twirl while playing. Just rotate. Sheesh... they can pick but they don't rotate much.

One of the reason why your guitar tones sounded thin with a single 57 on your "best speaker" is due to the time differential of the other speakers also making their way into that 57. That's phase cancellation. That's why you need to use a single speaker amplifier. Better still, install a couple of switches on your amplifier speaker cabinet. That way, you'll be able to turn off speakers you don't need to be recording. And that works also. It doesn't matter if your speaker is 16 ohms when your amplifier is telling you it's designed for 4 ohm loads. In fact, a 16 ohms speaker will take better advantage of the power that the amplifier can deliver in tonality. That's because the amplifier will not deliver at 16 ohms the power it delivers at 4 ohms and so it will saturate faster and at lower levels.

Real good quality, braided shield guitar cables may also help your noise situation. I'm not really into most esoteric cable crap but a good, all copper braided shield is hard to beat. But if it's the pickups that are causing the problem, you've got to find those stray, spurious electromagnetic interference transmitters in your general vicinity. You might need to build yourself a chicken wire fence box to sit in while playing? In fact the huge studio A at NBC-TV, Washington, DC, has chickenwire fencing surrounding the entire studio which is approximately 100' x 50' & 25 feet high. I mean you are right in the same building and underneath a tower with 2 TV stations & 4 FM stations just hundreds of feet away. So things sometimes have to be highly shielded. There is no other way to cope. So you have to try anything and everything to deal with the noise.

People tell me to take my finger and rotate upon it, frequently.
Mx. Remy Ann David

Geozen Wed, 01/25/2012 - 13:04

RemyRAD, post: 383347 wrote: I actually had a case of hydrocephalus. Which simply means that something swelled up within my cranium and crunched part of my brain like a hamburger patty. So maybe I just talked to much and that's the problem?

Irreversibly brain-damaged
Mx. Remy Ann David

Haha after I posted that response I was thinking to myself "Damn, everyone is gonna think I meant the bad kind of swelling" haha

RemyRAD Wed, 01/25/2012 - 15:13

That swell is the worst kind of swell one can possibly have. I feel so swell not feeling so swell anymore. Especially when feeling good. I can even think more clearly, though, there are many here that don't believe that to be true. My thought process is probably as clear as my API & Neve stuff and completely colored in my opinions. And since most of us come from both sides of the tracks, you don't want your cochlea confusing you. How can anybody hear anything clearly when the sound is directed down ever decreasing concentric circles before it finds its way to your brain? And with all those little hairs floating around, shouldn't one shave them once in a while? I want a straighter signal path to my brain. So shouldn't audio engineers all have cochlear implants so we can connect our hearing directly to our consoles? Instead of utilizing stupid speakers and bizarre labyrinths?

There was a young man from Nantucket...
Mx. Remy Ann David

jkleban Thu, 01/26/2012 - 16:04

Believe this or not, I have had some success with taking the pickups out of the guitar... wrapping aluminum foil on the underside and then mounting the pickups back in the guitar... it doesn't make the noise go away but does lessen it some and then if the guitarist rotates to the quiet zone, it can get much less noisy than without the foil.