Crest CA amps

[Ike]

I spent most of yesterday helping a friend out with a rack of over-heating crest CA9 and CA18 amps. For those of you who don't know the amps the have air intake fans at the rear which force air through the heat sinks and out the front.

 

The problem we found was that some clever person had removed the filters on the intake fans, presumably to save having to clean them, resulting in a huge amount of dust build up in the heat sink channels. After a couple of hours of cleaning it would be nice to be able to replace the filters but don't have any money to spend so I was looking for an alternative and was hoping that someone with one of these amps could tell me a bit about them, or maybe even post a photo. I want to try and get the nearest match to the original as possible so as to enable the highest air flow while still removing the most dust practical and have plenty of bits of filter like material lying round a raven store or two.

 

Thanks in advance,

 

Ike

[Simon Lewis]

Ike,

 

Replacement 120mm filters (such as RS 184-5141 ) are about 33 pence each.... even with a minimum order quantity of 5 and VAT on top, it's less than £2. If you don't have an account, try their trade counter.

 

The CA series are a solid, well built amplifier that sound pretty good. The CA18s were popular for LF use, but their weight means that a touring rack is stupidly heavy compared to modern switch mode PSU models.

 

One major drawback was that the component used as a mains inrush supressor tended to burn out somewhat catastrophically, something which (at the time) didn't help Crest's reputation.

 

Even if you have a dead CA18, it is worth holding onto as a replacement QE2 anchor ;-)

 

Simon

[ThomJ]

Well this is a thing, I have had a couple of ca6 go into protect from what we think is overheating (next day they seem fine).

 

Off the top of my head they no longer have the foam by the fans could a dust build up on the heat sinks be responsible for the over heating?

 

Thom

 

And yes they are great but heavy amps

[Ike]

Thanks Simon, wasn't sure if it was that type or the denser, thinner type.

 

Thom,

If you take the lid off, the ones we had had collected a LOT of dust just inside the fan and in the channels in the heat sinks that run the length of the amp (one on each side/channel). After dismantling one completly to clean it we found a very long bent pipe cleaner did almost as well at cleaning out the channels. Once we cleaned them the increase in air flow was very noticable.

[Rob_Beech]

Simon, you know you love them really.

 

I still have a rack of CA series (1 ea of CA18, CA12, CA9, CA4) that I'm keeping for no reason.

so they're up for sale if anyone wants to collect them. again as has been said. they are HEAVY.

I'll also put another ad in the classifieds section.

 

Rob

[jim b]

Thanks Simon, wasn't sure if it was that type or the denser, thinner type.

 

Thom,

If you take the lid off, the ones we had had collected a LOT of dust just inside the fan and in the channels in the heat sinks that run the length of the amp (one on each side/channel). After dismantling one completly to clean it we found a very long bent pipe cleaner did almost as well at cleaning out the channels. Once we cleaned them the increase in air flow was very noticable.

 

Compressed air down the heat sink channels does a similar job and brings the components back to looking like new-and is very time efficient. Many an overheating amp can be fixed in minutes this way.

[blueacid]

Well, a trick I have known to work on computers: tights.

 

Seriously, tights. They make alright air-filters; they do impede air flow a little, but nowhere near as much as a load of dust! They're cheap, and easily cleaned/replaced.