# EVH 5150 Noise, Bad Tubes ?



## dennissounds (Oct 3, 2012)

Hey Guys,

This is my first post on the sevenstring forum. 
I've got a question about my new EVH 5150 100 watt amp which I received a week ago.
When I turn up the volume on a channel i'm noticing a really loud hum/noise. 
Is it normal that this amp make so much noise ? 
I have also read some threads about bad tubes etc but since it's a brand new amp I don't want to open things up already.

Cab is a Zilla Fatboy 2x12.

Sample of the noise with volume turned up half-way:
Noise/Humm EVH 5150 by Dennis Van Verseveld on SoundCloud - Create, record and share your sounds for free


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## will_shred (Oct 3, 2012)

unless the amp has a built in noise gate it's going to hum. My blackstar has less gain than a 5150 and it hums a decent amount. Also florescent lights might contribute to hum, or it could be the shielding on your guitar. It could be a lot of things. and if it's not any of those things then you could just invest into a noise gate.


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## madrigal77 (Oct 3, 2012)

What channel is it? I have no abnormal noise problems with mine. From your clip, it doesn't sound like anything abnormal. On a high gain amp, there's going to be some hiss with the volume up.


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## Luke Acacia (Oct 3, 2012)

It sounds normal but I dont understand why it is swelling and then going down again, were you doing that with the volume knob?

I also think that it sounds like a hum from leads. 
Maybe just invest in a noise gate because you will need one anyway with an amp like that and see if that fixes it.


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## Leuchty (Oct 3, 2012)

You can chase "low noise" tubes, maybe pay a little extra, but Hi-Gain amps WILL make noise.


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## fitterhappier (Oct 4, 2012)

Sounds "normal" to me - some things you can do to help out the noise is invest in a power conditioner (may help if you have electrical issues in your house). Also try to make sure you're running it on as discrete a circuit as possible - meaning, you don't have it plugged into a power strip that's powering a bunch of other electronics or something like that.

But yeah - noise gate would cut down on that sound considerably. Out of curiosity, what kind of pickups do you have in your guitar?


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## capoeiraesp (Oct 4, 2012)

To the OP. I had a 5150iii 100w and had similar issues. It was strange because when I first got it 2nd hand it was a very quiet amp. Upon moving interstate and it having to travel on a train it became a noisy amp. I took it to a tech and had it thoroughly looked over. He managed to remove a fair bit of the noise but it was not as quiet as it was originally. 

Sorry that this isn't applicable to helping you fix it. He did say that the tube sockets were very poor quality and would wear only after a few tube changes. I had two microphonic preamp tubes and a damaged power amp tube socket. He also replaced some resistors, which from memory he said were also poor quality ceramic components (i think it was something like that) that shouldn't be used in such an amp.


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## dennissounds (Oct 4, 2012)

Thanks for the replies.
The swelling and going down again is because I turned the volume knob to half-way and back. The hum occurs on every channel.

I've tried to put a ISP decimator in front of the amp (guitar->ISP Decimator Pedal-> EVH 5150) but it didn't help, even with the knob turned up all the way. The hum was as loud with the pedal as without it. What I did notice was a popping sound when I pushed the pedal.

The pickups i'm using are EMG 85/81 and a bareknuckle aftermath set.


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## sugarman (Oct 4, 2012)

Put the decimator to the loop. I think the noise comes from the pre-amp. Also you should check out the pre-tubes.


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## madrigal77 (Oct 6, 2012)

capoeiraesp said:


> To the OP. I had a 5150iii 100w and had similar issues. It was strange because when I first got it 2nd hand it was a very quiet amp. Upon moving interstate and it having to travel on a train it became a noisy amp. I took it to a tech and had it thoroughly looked over. He managed to remove a fair bit of the noise but it was not as quiet as it was originally.
> 
> Sorry that this isn't applicable to helping you fix it. *He did say that the tube sockets were very poor quality and would wear only after a few tube changes.* I had two microphonic preamp tubes and a damaged power amp tube socket. He also replaced some resistors, which from memory he said were also poor quality ceramic components (i think it was something like that) that shouldn't be used in such an amp.


That's strange. Mine has Belton sockets, which are very high quality. I assumed they all did.


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## capoeiraesp (Oct 6, 2012)

The new lead engineer who came on board for EVH about 3 years ago changed their supplier to one company. Mine was an 08/09 model so I can only assume mine had sockets from a previous supplier.


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## dennissounds (Oct 6, 2012)

I've put the ISP Decimator in the loop and it took away a lot of the noise. But on the clean channel I still hear the noise above the sound while playing. 

And i've also found some diagrams with dates from October '07 so probably this is also an older model.


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## frogunrua (Oct 6, 2012)

I would exchange it for another one if the clean channel does it.


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## dennissounds (Oct 27, 2012)

Just found out where all the noise is coming from...

If I activate the FX-Loop and put the cable from the FX Send or Return to close to the transformer of the amp or the transformer of the Voodoo Lab the noise/hum occurs.

Does anyone know if this is a ground loop?
And would a Hum Eliminator like the Ebtech Hum eliminator help ?


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