Hartke HA3500 crackles

[Phil Starr]

Anyone else had problems in this area. I had a crackle on an amp that I bought from a bass chatter, which obscurely was worst every time I played a G! Fortunately the clue to the fault, vibration opening up a dry solder joint.

I went in tapping components and homed in on the power supply, sure enough there were a number of poorish looking bits of soldering and it turned out to be the regulator chip which is only supported on the soldered legs and has a too heavy heatsink clipped on, naughty Mr Hartke.

Anyway I checked over a tea break and it looks like I am far from the only one http://music-electronics-forum.com/t7354/ so if you have an odd crackle it isn't the valve necessarily or dirty connectors. Anyone else had this problem.

The amp however sounds awesome, well done Larry.


Oh, the link above will also link you to a circuit diagram if you need it.

[icastle]

Spot on diagnosis method there.

I've had about half a dozen Hartke amps apart over the last couple of years and all bar one of them had dry joint issues.

My understanding is that there were several batches of amps that suffered from poor soldering but the QC issue was resolved pretty quickly.

[brensabre79]

Never had a problem with my HA3500, awesome amp

My Genz on the other hand seems dogged with problems... It's gone through 5 preamp valves in a year!

I did/do have a Hartke A100 practice amp that's been in the repair shop for over a year due to an oscilating issue which won't go away. The amp tech says they are really poorly designed with long PCB tracks running the width of the amp back and forth. He also said his 8 year old son can do better soldering! Shame because they can make some really good stuff, but I think that particular model was done on the cheap.

[Twigman]

[quote name='brensabre79' timestamp='1363888740' post='2019026']
Never had a problem with my HA3500, awesome amp
[/quote]
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