Loud machine gun noise....

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zaphod_phil
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Re: Loud machine gun noise....

Post by zaphod_phil »

A machine gun noise could be from a faulty 12AX7. Those sometimes make various pops and crackles as they get old.
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jdubzamplification
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Re: Loud machine gun noise....

Post by jdubzamplification »

zaphod_phil wrote:
Tue 12/21/21 8:09 pm
A machine gun noise could be from a faulty 12AX7. Those sometimes make various pops and crackles as they get old.
Swapping tubes makes no difference. I initially thought it was a tube issue honestly.
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Re: Loud machine gun noise....

Post by Bieworm »

you must be a very patient man... If I had an amp sitting on my bench for 3 weeks straight with a defect, you'd have to tranquilize me or I start breaking stuff!
How can we help you if you don't show us watcha got? A lot of problems were solved by us staring at detailed pics. Have you already tried isolating the problem? Pulling tubes one by one, disconnecting plate wires one by one,...we haven't the faintest idea what you tried thus far, except tube rolling, doing stuff with ground connections,...
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Re: Loud machine gun noise....

Post by jdubzamplification »

Bieworm wrote:
Wed 12/22/21 4:49 am
you must be a very patient man... If I had an amp sitting on my bench for 3 weeks straight with a defect, you'd have to tranquilize me or I start breaking stuff!
How can we help you if you don't show us watcha got? A lot of problems were solved by us staring at detailed pics. Have you already tried isolating the problem? Pulling tubes one by one, disconnecting plate wires one by one,...we haven't the faintest idea what you tried thus far, except tube rolling, doing stuff with ground connections,...
Well, my son's basketball schedule and full time job has hindered me some the past several weeks, along with Christmas shopping and decorating.... so.... lol.

Sorry I will get you some pics soon.

Pulling the Tremelo tube (V3 in my case) stops the war (lol). Pulling V2, the noise is still there with but very very faint due to no amplification on that channel.

Thank you for replying, I will get pics as soon as I can.
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Re: Loud machine gun noise....

Post by jdubzamplification »

Here are some pics... I started unhooking things to see when the problem stopped....
DISCLAIMER-This is not one of my builds.....
IMG_1671.jpeg
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Re: Loud machine gun noise....

Post by JMPGuitars »

That build looks like a nightmare. No offense to whoever did build it. There's 1000 things wrong there. The wires are still a mess, there's essentially zero mechanical connections on the not very good soldering, etc.
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Re: Loud machine gun noise....

Post by jdubzamplification »

JMPGuitars wrote:
Wed 12/29/21 8:44 pm
That build looks like a nightmare. No offense to whoever did build it. There's 1000 things wrong there. The wires are still a mess, there's essentially zero mechanical connections on the not very good soldering, etc.
Agreed... I thought about just ripping it all down and starting over... but..
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Re: Loud machine gun noise....

Post by Daviedawg »

It has all the hall marks of having had a doze of troubleshooting already.

Dd
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Re: Loud machine gun noise....

Post by JMPGuitars »

jdubzamplification wrote:
Wed 12/29/21 9:11 pm
JMPGuitars wrote:
Wed 12/29/21 8:44 pm
That build looks like a nightmare. No offense to whoever did build it. There's 1000 things wrong there. The wires are still a mess, there's essentially zero mechanical connections on the not very good soldering, etc.
Agreed... I thought about just ripping it all down and starting over... but..
But, if you do that, it might be less work and a better amplifier. ;)
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Re: Loud machine gun noise....

Post by jdubzamplification »

JMPGuitars wrote:
Thu 12/30/21 8:53 am
jdubzamplification wrote:
Wed 12/29/21 9:11 pm
JMPGuitars wrote:
Wed 12/29/21 8:44 pm
That build looks like a nightmare. No offense to whoever did build it. There's 1000 things wrong there. The wires are still a mess, there's essentially zero mechanical connections on the not very good soldering, etc.
Agreed... I thought about just ripping it all down and starting over... but..
But, if you do that, it might be less work and a better amplifier. ;)
I hear ya!

I rewired the preamp section, reflowed all the joints and replaced a coupling cap and problem is now gone.

I am now interested in building one of these .... strangely enough...lol

Thanks all!
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Re: Loud machine gun noise....

Post by JMPGuitars »

That's good news! I figured rebuilding the section in question would do the trick. Unfortunately that leaves the rest of the amp...as it was.

On the bright side, it works! And now you can build your own.

Thanks,
Josh
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Re: Loud machine gun noise....

Post by jdubzamplification »

JMPGuitars wrote:
Thu 12/30/21 6:35 pm
That's good news! I figured rebuilding the section in question would do the trick. Unfortunately that leaves the rest of the amp...as it was.

On the bright side, it works! And now you can build your own.

Thanks,
Josh
Thank you Josh! The owner would be upside down in the amp if I had spent much more time on it... unfortunately!

Do you have a template for a for a fiberboard?

Thanks!
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Re: Loud machine gun noise....

Post by JMPGuitars »

jdubzamplification wrote:
Thu 12/30/21 8:43 pm
Thank you Josh! The owner would be upside down in the amp if I had spent much more time on it... unfortunately!

Do you have a template for a for a fiberboard?

Thanks!
Ah, that makes sense.

Take a look in the downloads section: viewforum.php?f=25

If it's a layout I made, it's scale 1:1 (when printed full size). There's others there that aren't 1:1, but still good stuff.

Thanks,
Josh
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Re: Loud machine gun noise....

Post by Bieworm »

That IS good news indeed!
When building your own you might consider Josh's tremolo TMB. Josh has circuit boards for sale that really rock! I gave one in my 36W tremolo TMB reverb. Love it!
BTW Josh, yesterday I sold one of my tremolo tmb amps.. the owner is super satisfied with that beast ( his words)
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