Ashdown ABM 500 EVO III - fuses blown.

[paddy109]

Last night's gig my ABM 500 started well and sounded great then just stopped mid gig.

Transpired the fuse under the power in had blown. Replaced the fuse like for like and it blew again straight away.

Anyone else had this happen and can share their knowledge, suggest a fix.

I've messaged Ashdown.

Paddy.

[DGBass]

Could be a number of things, and Ashdown are probably the best people to contact as theses amps are eminently repairable. From personal experience, blowing the mains input fuse usually points the finger in the direction of the ouput board, maybe a shorted output device ( there are six bi-polar output transistors on the output boards. A failed/shorted one can overload a rail and blow the fuse ). I've never seen the pre-amp section ever fail in one of these amps and blow a fuse. For the most part I haven't seen a transformer go bad either in an EVO III amp. These versions are tuned to run at 575 watts so there is a lot of juice going through them. The bi-polar devices only usually fail prematurely if they aren't getting cooled properly over time or the heatsinks being clogged with accumulated dust/grime over the years can affect cooling. There is also a thermal cut out so even if it was poor cooling the amp would cut out long before something actually failed and work again after it had cooled down. Basically not a DIY easy fix if the mains is blowing. Ashdown should be able to sort your issue out easily. I always keep a fully working spare output board but touch wood, I've never needed it so far🙂

 

[paddy109]

After talking to Dave @ Ashdown and trying a couple of new fuses the ABM was sent to HQ today. 

[basstone]

Ashdown are really good at supporting their customers so your amp is in good hands. Let us know what they find please.

[paddy109]

I had a great chat with Dave from Ashdown. Bad news the amp needed a new power board and perhaps had been tinkered about with before. Good news the amp now has a clean bill of health and should go on for a number of years.

Dave was great with his communication and his dry wit made me laugh even though I was parting with my hard earned money.