Jump to content
Why become a member? ×

What's wrong with my Hartke amp?


Recommended Posts

This amp was working fine until last Friday night, signal cut out, it was really hot and then started making this noise. In the video the volume is turned down to 0 and it still makes the noise.

Any ideas anyone and someone who might be able to repair?[attachment=220896:IMG_1513.MOV]

Edited by Gunsfreddy2003
Link to comment
Share on other sites

I couldn't play the clip but something which makes a noise and isn't affected by the volume control sounds like a power supply fault to me too. If the sound is a very loud buzzing I'd suspect the power supply capacitors. If it is you shouldn't mess around with them unless you know what they do. They can give you a nasty shock even with the amp unplugged/switched off.

Link to comment
Share on other sites

[quote name='Phil Starr' timestamp='1465428387' post='3068230']
They can give you a nasty shock even with the amp unplugged/switched off.
[/quote]

This - their job is to store charge until called upon to discharge it. All at once, right up your arm.

Not pleasant. :(

Link to comment
Share on other sites

I have opened up the amp and can't seem to see any fuses on the PCB - happy to be enlightened if anyone can see something that I am missing on the pic!

Where are the power supply capacitors that I need to wary of?



[quote name='MoonBassAlpha' timestamp='1465212811' post='3066109']
Could be one rail of the power supply gone. Have a look for any fuses internal, mounted on the PCB(S) and see if any have gone.
Usual warnings about poking around inside gear apply - Unplug from mains etc.
[/quote]

Link to comment
Share on other sites

[quote name='Gunsfreddy2003' timestamp='1465760767' post='3070822']
I have opened up the amp and can't seem to see any fuses on the PCB - happy to be enlightened if anyone can see something that I am missing on the pic!

Where are the power supply capacitors that I need to wary of?
[/quote]

The caps are the black can looking things and smaller blue ones. But keep away from the large ones.
Is it me or does the resistor between the heatsinks look a little burnt on the board??

Since you didn't know which were the capacitors then I advise you fasten it back up take it too a tech as you really can get hurt.

Edited by Twincam
Link to comment
Share on other sites

Yes, I think that is probably the best course of action - I was just hoping for a quick fix I could have done myself.

I'm not sure that the amp is worth spending the money on for any kind of repair to be honest.



[quote name='Twincam' timestamp='1465787584' post='3070949']
The caps are the black can looking things and smaller blue ones. But keep away from the large ones.
Is it me or does the resistor between the heatsinks look a little burnt on the board??

Since you didn't know which were the capacitors then I advise you fasten it back up take it too a tech as you really can get hurt.
[/quote]

Link to comment
Share on other sites

Amps where the components can be changed are often quite cheap to repair, and parts will be available for many years to come.
More modern class D amps use modules, and will be much more difficult to repair when the manufacturer stops making those modules.

In short, check the cost of repair before binning it.

David

Link to comment
Share on other sites

[quote name='Twincam' timestamp='1465787584' post='3070949']
The caps are the black can looking things and smaller blue ones. But keep away from the large ones.
Is it me or does the resistor between the heatsinks look a little burnt on the board??

Since you didn't know which were the capacitors then I advise you fasten it back up take it too a tech as you really can get hurt.
[/quote]

+1 and the 2nd resistor above the inductor (greeny-blue coil) on the right hand side above big smoothing capacitors also looks a little 'charred'. (might be shadow in photo though).

The big plus is that your Hartke is traditional discrete components on 'big' PCB. This means repairable at sensible costs. I doubt the components that need replacing cost more than £5, this money will be in labour costs, diagnosis and time.

Edited by 3below
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...