amp hum

[imcorn]

Hmm.. just grounded (2pin -> 3pin plug) a new pathfinder 15R and i find it causes some hum when the gain knob is past a certain threshold (around 3o'clock).. the hum is more significant when the boost function is on.. and all this happened when the guitar or effects is not even plugged in..


is this normal? Anyway to reduce the hum?

 

[thor666]

Experts correct me if I'm wrong here...

Past a limit of volume/gain, all amps will hum. you could attempt to check for proper shielding and grounding on an amp but that should be done only by an expert - amp voltages are lethal.

 

[Phil]

Mine hums too when pushed high. But it doesn't occur when the tone knob on my axe is turned down lower.

 

[fraggot]

1st make sure your problem is indeed hum and not buzz.

hum is like a constant lower frequency sound, not particularly annoying and some find it pleasing. and yes all guitar amps i've come across hum when the gain is turned up.

buzz is more like interference/ electrical noise. sometimes will have sometimes dun have. and very apparent like an extra tone/note going off inside the amp.

i'm using a 15R and i'm suffering from buzz

tried bringing to mikeman to fix but his studio electricity mus be better than mine... down there no buzz.. at home buzz like siao, esp when i try to use the reverb function.

 

[metalella_eh]

okay, let's say my set up is guitar -> DS7 -> TS808 -> amp. my guitar tone is set to 0. my pedals are functioning normally. absolutely no humming and buzzing from my pedals. even when with drive are set to max. but when i turn the tone on on my guitar, there's a very loud buzzing. what's wrong with my guitar?

 

[DarknessFury]

Erm, hijacking the thread for a moment...I have this buzz which is irritating but when I touch the output jack on the guitar, the buzz becomes real soft...but when I touch the other metal parts on the guitar, it gets slightly louder...why? I didn't have such problem before...

 

[ShredCow]

Metelleh, and Darkness, its prob your guitar's grounding.

Can all of you in this thread, complaining about hum/buzz/noise from your amp, please list the gain you play at?

 

[DarknessFury]

My amp's High is at 10...

 

[ShredCow]

Okay, how about listing down all your eq settings?

Bass:
Mids:
Treble:
Gain:
Presence:
Reverb:

 

[DarknessFury]

Erm, my amp doesn't have all that settings...it only has

High: 8
Mid: 4
Low: 2

The range for these settings are from -10 to 10...

 

[MrE]

Erm, hijacking the thread for a moment...I have this buzz which is irritating but when I touch the output jack on the guitar, the buzz becomes real soft...but when I touch the other metal parts on the guitar, it gets slightly louder...why? I didn't have such problem before...

dude... from what you describe abt the buzz(hiss) going away when you touch the metal parts (what you're actually doing is grounding the amp by letting the stray current run through you instead of coming thru your amp as hiss) - seems to me your amp has not been grounded.

see this thread:

http://soft.com.sg/2006/modules.php?name=Forums&file=viewtopic&t=11443

 

[DarknessFury]

Oh, so it's an amp problem and not my guitar's problem? Ah...that's good...'coz I'm gonna get a new amp soon...

 

[MrE]

Oh, so it's an amp problem and not my guitar's problem? Ah...that's good...'coz I'm gonna get a new amp soon...

well make sure you ground your new amp once you get it, or u will have the same problem again.

 

[dwarfstars]

Erm, hijacking the thread for a moment...I have this buzz which is irritating but when I touch the output jack on the guitar, the buzz becomes real soft...but when I touch the other metal parts on the guitar, it gets slightly louder...why? I didn't have such problem before...

dude... from what you describe abt the buzz(hiss) going away when you touch the metal parts (what you're actually doing is grounding the amp by letting the stray current run through you instead of coming thru your amp as hiss) - seems to me your amp has not been grounded.

see this thread:

http://soft.com.sg/2006/modules.php?name=Forums&file=viewtopic&t=114 43

not true that you ground the amp.. the strings are grounding you.. the other way round... our body resistance is too high .. yup.. i read that somewhere before..

 

[MrE]

[
not true that you ground the amp.. the strings are grounding you.. the other way round... our body resistance is too high .. yup.. i read that somewhere before..

how can the strings be grounding me? i'm not an electrical appliance :lol:

are you thinking in terms of the direction of current flow - i.e. electrons flow from me to the amp to ground it?

either way you look at it, by touching the strings or other metal parts, you are completing the ground.

 

[metalella_eh]

thanks shredcow for the help. i'll seek a luther's attention on that matter.

 

[theblueark]

how can the strings be grounding me? i'm not an electrical appliance :lol:

are you thinking in terms of the direction of current flow - i.e. electrons flow from me to the amp to ground it?

either way you look at it, by touching the strings or other metal parts, you are completing the ground.

This is a common misconception.

You can't ground anything because you are not a ground. In an electrical circuit operating at signal voltages, a common return path that is the zero voltage reference level for the equipment or system.

While I'm at it, here's another misconception.
This signal ground may or may not actually be connected to a power ground. So your signals are not grounded to earth.

The strings ground you becuase the strings are connected to the signal ground (on most guitars anyway, some are not). Anything that is connected to the ground is grounded.

Getting confused? Ok see, your guitar has 2 wired connections to it. One is a 'live' signal, one is a 'ground'. This 'ground' is actually a reference point, it never changes. Your 'live' signal dances around this reference, and it is this dancing around that your effects see and your amp sees and the speakers see and vibrates according to. The problem is your body is a huge antanae attracting all sorts of noise (dancing voltages). So what do you do? You touch the strings, then all the dancing voltages become whatever voltage the strings are at, which is a constant. Thus, no more noise.

Read more here if you are interested:
http://www.guitarnuts.com/technical/noisebucket.php

 

[MrE]

wah.. the dancing voltage theory very cheem lah, blueark.

but i got a better idea after reading that link. thanks for clearing the air once again