Beard P100 mk1 owners? And some questions

[Colin151]

Was wondering if anyone had any advice on this? Would be much appreciated.

I bought a Beard P100 mk1 the other day and it has an intermittent fault in the left channel. Sometimes there is distortion and the sound decreases in volume in the left. Comes and goes. I was advised this is likely a bad cap, but I guess it could be a cold solder joint too.

I looked inside the amp and it's had some upgrades. Some of the original caps have been upgraded to Mundorf Mcaps, and the original Carbon composition resistors have been upgraded to metal films. One of the Mundorf coupling caps in the left channel has a bulge at the end. Here is a pic. Its the second one from the front left.
http://hantarex.com/View%20from%20other%20side.jpg

Someone I asked said he thought this was normal with these caps (he said that visually they sometimes have a concave and convex end), but oddly the other same caps don't look like that. There is no bulging in the middle of the cap. It does seem odd that a non electrolytic cap would bulge. The voltage rating of them is 630V so easily high enough I would have thought.
Anyone any ideas on this?

I guess I should try going over the solder joints in the left channel first, in case there is a dry joint. If the fault does not then go away I'll change these caps. I already tried swapping around the tubes, left to right. no difference in the fault its still on the left.

Finally. I saw the service manual for the P100 mk2 and those caps have different values. Though I have a mk1 I want to double check the cap values are correct/stock. If anyone has a MK1 might they be kind enough to have a quick look in the amp to see what the values are? I'm interested in the 12 caps shown in the picture above. The original caps are grey rectangular ones I believe.

[User211]

If you look at my BB100 thread, you'll see photo of a repair bill on mine. This chap is recommended. He did well more than asked and charged vey little. I paid him more than he wanted.

For peace of mind just get him to check it out is my advice.

[Colin151]

Thanks for the info. I'll have a look at your thread.
Whereabouts is this chap based?

Cheers
Colin
If you look at my BB100 thread, you'll see photo of a repair bill on mine. This chap is recommended. He did well more than asked and charged vey little. I paid him more than he wanted.

For peace of mind just get him to check it out is my advice.

[User211]

You shoulda bought mine. It was serviced, has a shed load of new components in it, and it will blinking well work for a long time without going wrong! It also has the user/service manual. That took me a lot of effort to obtain. It is useful to any service engineer.

More seriously, I think you need more than 50 Watts, so I understand why you didn't.

You'll have to post it - he's in Bristol. He WILL fix it well, though. You can just tell from his attitude he wants good problems to solve:) The best kind of engineer.

You could try and e-mail http://www.beardaudio.com/ for the manual with your finger's crossed.

They used to sell P100s with GEC KT88s in them in 1990. Wowser!

[Reffc]

I'd re-flow some of those solder joints as a first port of call. I don't know whether I'd apply terms like "upgrade" to such poor soldering...whoever did that has left large blobs of dull looking solder on many joints and hasn't left things very clean or tidy. Its possible that it might be a poor solder joint. Looks like a DIY job to me by someone with poor soldering skills. Most of those Mundorf caps should be identical. They shouldn't have a bulge like that and I can see that the outer wrapping is parting company. Could be they're getting very hot in those positions or something else is going on but the coverings don't usually part company like that without reason. If it were my amp, I'd remove each cap and test it, remove the excess solder build up and clean everything up properly before re-soldering things in neatly.

[Firebottle]

+1 for removing each cap and testing them.

Whether the cap in question has a bulge or not is difficult to say, it may just have suffered an 'overfill' at that end. There does seem to be a bit of variation of filling of the ends.
The outer wrapping is possibly coming adrift due to heat drying the adhesive.

:cool: Alan

[loo]

Hi, apart from the bulging cap which is definitely not as it should be Mundorf don't send out caps like that, the thing worrying me is that when you look closely
all the Mcaps seem to be peeling or loosing their wrapper which is not right I would consider the possibility that they are dodgy as in counterfeit caps and not
genuine Mundorfs , I know Kendeil had a massive problem with Chinese counterfeits perhaps they are not alone .
But definitely get it fixed by someone that knows what they are doing , Justin's man sounds good and comes endorsed ;)
good luck
cheers
Paul