I'm looking to recap my pentas, but am having a hard time tracking down some 10,000 uF/80v capacitors for the main power supply. 10,000/100v are easy to come by, but all seem to be 40+ mm in diameter which wont fit.

Farnell show 10,000/80v in their system, but none are in stock. These will be an easy fit at 35mm dia and 50mm long.

 Has anybody else done this job? Who was the supplier?

 

Cheers,

Ben

Dillen in this forum is my number one supplier of capacitors. I've just been in contact with him regarding these caps, and he says that he is out of stock at the moment, but he has ordered more, and they should be available in a couple of weeks. Send him a PM.

My normal supplier has changed brand so I am currently working with a new supplier in search for a solution to this problem. Hope to have something available shortly. 

Martin

I have some 10.000uF 80V in stock now (35x52mm).

PM me for details. 

Martin

Hello,

I have a beolab penta which suffers of a kind of humming in the speakers, like some static electricity is building up.
I've got the potmeters checkes, but without result. I've changed the caps in the soundpart, but also without success.

Could recapping the powersupply would do the job?

Kind regards

Joost Declercq,
Gent

Gent,

Is the humming present also without an input signal (light green) ?

Does the cooling fin or transformer become hot just by being powered on ?

Like everywhere else, capacitors age and cause problems. The Beolab Penta speakers are no exception so caps cannot be ruled out. I normally repair the older audio stuff but more and more people come to me with Penta problems and a wide solution is hopefully underway; 

A Beolab Penta upgrade kit containing a full set of new capacitors (all 105deg rather than the original 85deg) both for the power supply and the amplifier, new and better opamps and signal path coupling capacitors for the preamp and audiophile filter capacitors for the crossovers is in the making, hopefully ready very soon.

Martin

Hi,

Well, the humming is indeed sometimes present, without a source (for instance, when the CD ended).  It sounds like static crumbling and isn't affected by the volumecontrol.

I haven't yet checked the heat of the cooling fin.  I'll check that, when they are back in the livingroom (moved them, to do some painting).

I've changed the caps and opamps in the amplifier and the crossovers, but not yet in power supply.  So, I'm interested if there's a set of capacitors for that.

PS: my name is Joost.  Gent is the place where I live :)

Joost 

Joost:

Silly question, but it has happened to me more than I care to acknowledge...

Are you absolutely certain that the noise is originating from the Pentas?

 Ie. with no signal cable plugged in, do you hear the same noise?

Sometimes we over look the obvious; the problem could be originating from your Beomaster or from faulty signal cable and that the Penta amp is fine. Plug your ipod or some independent source in and see if the Pentas still act up. And to be sure... swap everything over to the other Penta to confirm.

Just double check :)

Derek
 

 

I had hum coming from the transformer in one of my pentas. When I put my hand against the amp, I could feel it vibrating. After replacing the 10000uf 80v caps in the power supply, it went away completely.

Hello,

 thanks for all the suggestions.

I tried all different connections and positions.  I changed cables, sources, powersockets, changed from daisychaining the powerlink to seperate powerlink,.... I connected other speakers to the beomaster, active and passive, but they sounded ok...  Well, I'm out of inspiration.

The sound I hear isn't really humming, but more some kind of cracking, like when switching radiostations with an old analog receiver with dial (well, something like that).  The cracking isn't always present.  That's the problem, because I brought it twice to my dealer, but he didn't hear anything :-(.

I changed the caps in the amplifier, without result.  Could recapping the powersupply do any good?

kind regards,

Joost 

Don't think recapping the PS would do anything.

Maybe there is a broken trace somewhere in the signal path between the sockets and the amplifier. I'm assuming that you have tried the line in-socket?
 

Hi,

 

Sorry to disturb you but I've founded your commentary trhough a google search and I'd like to ask you with what kind of cable I can plug my IPOD directly to the BEOLAB PENTA amplifier. I  bought a 2 RCA cable joined to a powerlink (5 plots) connection but it doesn't work with it !? How do you do it ?

 

Thanks in advance

Henri

The Penta transformers are underrated for the amp capacity and are known to "expand" over time. There was a thread on here showing the state of the box inside and the hum seems to be a tell tail sign.

Search the forum for "Penta bookmark this" thread and read. Good luck.

I don't agree.
The idle current trimmers are what fails.
They lose connection, making the amplifier idle current way too high, almost Class A.
The transformer is not dimensioned for Class A, it will introduce hum and it will become hot and
that in turn affects the capacitors that sits right next to it.

The photo of the meltdown is a typical example of an owner unaware of the condition of the amplifier.
It would have been really hot and the smell would have been really bad to get to this state and
still it was obviously left powered on.

Martin

Henri,

Welcome to Beoworld ! 

Please put your question on the general forum as a new thread. This thread is about the power supply of the Penta speakers and
may not attract the people who can answer your question.

Martin