Reply to this topicStart new topic
> Crackling Sounds From Amp
enlo22
post Jan 6 2015, 02:37 AM
Post #1


Learning Guitar Hero
*

Group: Members
Posts: 416
Joined: 24-December 11
Member No.: 14.670



lately when I turn my amp from standby to on it starts to make a popping sound, I've replaced the power tubes, tried different cables and without the guitar plugged in, plugging it in at a different place. etc, still makes that sound, other times it'll sound lke the volume drops for a second. It makes a sound as if the air conditioner tuned on or soemthing, that's the best way i can describe it lol, but like it looses power for a split second or so... idk what it could be anymore i've researched and nothing :/ hopefully some one can help me out a bit.


--------------------
Go to the top of the page
 
+Quote Post
GregH
post Jan 6 2015, 03:12 AM
Post #2


GMC:er
*

Group: Members
Posts: 169
Joined: 30-July 10
From: Oregon, USA
Member No.: 10.944



What kind of amp is it?
Go to the top of the page
 
+Quote Post
fkalich
post Jan 6 2015, 03:48 AM
Post #3


GMC:er
*

Group: Members
Posts: 2.728
Joined: 12-February 07
From: People's Republic of Lawrence Kansas
Member No.: 1.189



I would suspect a bad preamp tube. Or poor connections due to corrosion. You should clean the prongs and sockets with aerosol electronics cleaner. That often is the problem. Or move some preamp tubes around and see if things change. Assuming all your preamp tubes are the same. Sometimes a vender will select a special tube for some slot. On some sets a couple of the tubes may be hand selected for some slots. But they are usually the basic type and can be switched around. Or perhaps you have a spare. Just remember which originally went where in case you want to revert to square one. They are not like power tubes that should be matched pairs and they don't need to be biased as power tubes do.

b.t.w. I had an amp doing this a few weeks back. I cleaned the tube prongs and sockets and swapped around a couple preamp tubes. I can't remember which I swapped, Carvin tells you which does what so I just did some figuring about where the problem likely was and which socket was least critical. One of them is dedicated to reverb on that amp. The Carvin instructions give some guidance on what tubes are likely to be causing what problems, but I don't know about your amp. But I suspect that in my case the connections just needed a good cleaning, problem all gone now.

QUOTE (enlo22 @ Jan 5 2015, 08:37 PM) *
lately when I turn my amp from standby to on it starts to make a popping sound, I've replaced the power tubes, tried different cables and without the guitar plugged in, plugging it in at a different place. etc, still makes that sound, other times it'll sound lke the volume drops for a second. It makes a sound as if the air conditioner tuned on or soemthing, that's the best way i can describe it lol, but like it looses power for a split second or so... idk what it could be anymore i've researched and nothing :/ hopefully some one can help me out a bit.


This post has been edited by fkalich: Jan 6 2015, 05:07 AM
Go to the top of the page
 
+Quote Post
Todd Simpson
post Jan 6 2015, 08:05 AM
Post #4


GMC:er
Group Icon

Group: GMC Instructor
Posts: 14.478
Joined: 23-December 09
From: Atlanta, Georgia, USA
Member No.: 8.794



I'm sure somebody here perhaps DARIUS WAVE, who uses tube amps can pitch in an help smile.gif Maybe shoot him a PM? Here is his instructor page.

https://www.guitarmasterclass.net/instructor/Darius-Wave/

I"m more of a plugin / modeling guy myself smile.gif


QUOTE (enlo22 @ Jan 5 2015, 09:37 PM) *
lately when I turn my amp from standby to on it starts to make a popping sound, I've replaced the power tubes, tried different cables and without the guitar plugged in, plugging it in at a different place. etc, still makes that sound, other times it'll sound lke the volume drops for a second. It makes a sound as if the air conditioner tuned on or soemthing, that's the best way i can describe it lol, but like it looses power for a split second or so... idk what it could be anymore i've researched and nothing :/ hopefully some one can help me out a bit.



--------------------
Go to the top of the page
 
+Quote Post
Darius Wave
post Jan 6 2015, 01:32 PM
Post #5


Instructor
Group Icon

Group: GMC Instructor
Posts: 5.294
Joined: 29-November 12
From: Poland
Member No.: 17.069



The problems You mentioned in most cases are in fact caused by the corrosion or damaged power tubes. Unfortunately tube amps are sort of like a car...old car. There are at least few causes that can be guilty for what You describe. If changing tubes and removing corrosion (WD40 or similar, just a drop on each pin of each tube) then I highly suggest to not dig in it by yourself. Tube Amps use extremely high voltage. It's very easy to hurt Yourself...electric shock. Also You can cause a failure of different element of the amp.

I would take it and go to a service. It might be something wrong with it's power supply (usualle capacitors but transformer could failed as well.

In case of amps there;sa huge risk You'll not save any money by trying to repair by yourself.

I don't know if this does make You feel any better but I'm having an amp issue at the moment same as You smile.gif Waitinf for new powertubes. Hope it's the only cause since one started to glow differently than the other one. It's a 30Wattr amp and a very first pieces from the series and they did those on EL34 before. I heard Cornford change thier mind to 6L6 in this amp. Don't want to screw the exact explanation but let's try to simply say taht EL34 had a little too big "kick in the a$$" in this particular circut. So I suppose they simply exploited.

If the reason is different, I'll simply go to a service.


--------------------
Go to the top of the page
 
+Quote Post
klasaine
post Jan 6 2015, 04:36 PM
Post #6


GMC:er
*

Group: Members
Posts: 2.822
Joined: 30-December 12
From: Los Angeles, CA
Member No.: 17.304



Unfortunately these can be symptoms for several potential problems.

The volume drop is usually a power tube but it can also be something called a screen resistor (1K). Have any of the power tubes completely failed in the past? If so, the failed power tube can draw excessive current on the screens, causing the screen resistors to fail.

As for the pop when you take it out of standby ...
Does it just pop once when you flip the switch or does it pop continuously?
If it only pops once, that's actually normal with a tube amp. When your amp is turned on and running there is a constant supply of voltage running through your amp. When you throw the standby switch from On to Standby, you are disconnecting the high voltage half of the power supply. This is releasing a lot of energy. When connecting or disconnecting high voltage there is always the possibility that the surge of the voltages will produce a pop sound.

*As Darius mentioned - if you don't know what you're doing, do not poke around inside your amp. Even unplugged it can have enough voltage stored in the capacitors to kill you .


--------------------
Go to the top of the page
 
+Quote Post
enlo22
post Jan 6 2015, 05:31 PM
Post #7


Learning Guitar Hero
*

Group: Members
Posts: 416
Joined: 24-December 11
Member No.: 14.670



I think i'm going to take it to get it service, I wish it was cheaper to do that but I guess it's worth it...
The amp is a Peavey 6505+ head, and I did the whole cleaning the sockets and it still being funny :/ so i'm guessing it's something more serious hopefully it's not going to cost me a ton of money to fix, and hopefully the technician actually knows what they're doing !


--------------------
Go to the top of the page
 
+Quote Post
Todd Simpson
post Jan 7 2015, 01:49 AM
Post #8


GMC:er
Group Icon

Group: GMC Instructor
Posts: 14.478
Joined: 23-December 09
From: Atlanta, Georgia, USA
Member No.: 8.794



Very good advice from the guys!!! Take that thing in for service for sure. Hopefully it's something small and cheap that can be fixed quick. smile.gif


QUOTE (enlo22 @ Jan 6 2015, 12:31 PM) *
I think i'm going to take it to get it service, I wish it was cheaper to do that but I guess it's worth it...
The amp is a Peavey 6505+ head, and I did the whole cleaning the sockets and it still being funny :/ so i'm guessing it's something more serious hopefully it's not going to cost me a ton of money to fix, and hopefully the technician actually knows what they're doing !



--------------------
Go to the top of the page
 
+Quote Post
GregH
post Jan 7 2015, 05:24 AM
Post #9


GMC:er
*

Group: Members
Posts: 169
Joined: 30-July 10
From: Oregon, USA
Member No.: 10.944



The 6505 is a pretty straight forward design. A capacitor breaking down or a cold solder joint are also likely problems. I have a lot of years of working on tube amps but the bottom line is that unless you personally are comfortable working around 400 volts dc (and have test equipment like a scope) the best advice is to take it to someone who is.
Pops and crackles can be frustrating to trouble shoot if they are intermittent in nature. It is almost a sure thing that it won't do it once it is apart on the bench. On the other hand, if you can make it act up on command, then a good technician can go right to the problem.
Go to the top of the page
 
+Quote Post

Reply to this topicStart new topic
1 User(s) are reading this topic (1 Guests and 0 Anonymous Users)
0 Members:

 


RSS Lo-Fi Version Time is now: 27th May 2017 - 09:00 AM