Replacing components on Creek 4140

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My Creek 4140 integrated (2 channel) amp began blowing the AC mains fuse but not the two fuses inside the case. I contacted Creek technical support and they recommended changing the transformer. I have ordered a new transformer but was also going to replace the power supply caps with newer polarized electrolytic caps. While I was doing that, I might as well replace the diodes, op amps (by the way -- any articles on which op amps are better?), and other caps.

My question is that I have two large 6,800uf capacitors. I've found some nice capacitors of the same capacitance. Can I also put in larger capacitance caps (say, 10,000uf, which will fit in the case). Would there be any benefit to doing so?

I do have part of the power supply circuit diagrammed out, but this is a tedious process. Does anyone know where a circuit diagram for the Creek 4140 would be?

Thank you!
 
The Creek 4140 is a wonderful transistor amp build by english engineers, BTW they are tube fans. Once I tested a 4140 against 2 Krell monos and guess what - 8 people couldnt tell the difference!!! This shows again what a rip-off Krell and many other high priced transistor amps are.

Now to the subject, I don't have a schematic but I would recommend ultra fast diodes with 0,01 to 0,033 caps in parallel, good sounding large caps like Elna or Epcos with parallel caps (matter of taste) and Analogue devices op-amps. I would also cut all the pcb signal lines and replace it with pure silver wire max. 0,5mm. Don't forget to clean the speaker outposts - very important with this amp due to the material they used. Get rid of the plastic feet - very nasty sounding indeed - and replace it with ceramic/kevlar/carbon or something alike, even pocellan is better than metal or plastic.

I've done all this for 2 friends of mine, they were shocked about the gain in detail, space, speed and clarity.
 
I like the 4140, especially considering the price. I've ordered two sets of capacitors for the main PS capitors, one set at 6.8mf and one at 10mf. In order to repair the 4140, I'm going to replace the PS caps and the transformer. I've ordered all replacement capacitors in the signal path, diodes, and op amps, but those will have to wait awhile. I may also initially put in the 6.8mF caps and wait until I have time to test how the 10uF caps would work. Additionally, I may diagram out the entire circuit, as I'd like to begin reusing my EE skills (once a practicing EE, I'm now a patent attorney). I'd like to plug at least part of the data into a program like Tina and see what if any effect 10mF would have as per 6mF caps on the PS. I can then use a scope and verify the effects.

I'm also interested in seeing what happens when I replace the diodes, etc., but that will have to wait awhile -- I have to insulate my house, which will likely take all my time the next three weekends.
 
The thing with the ultra-fast-diodes is not solved yet. Nelson Pass don't like the ufd's, but maybe they sound too clean (analytical) on his amps. I think it's a good idea at least for the Creek - more speed and detail is recommended for this smooth (maybe too smooth) amp.

It is strongly recommended to replace the original signal caps with Solen or something alike. The Solens are cheap and very fast & dry but a little distorted in the highs. The solution for this problem is also cheap: use a Sprague Orange Drop 0.001 in parallel and you can compete with the most expensive caps sold out there. At least in the speed department you can beat the hell out of some nasty overprized caps.
 
Hello, this is my first posting on diyaudio. I have acquired a Creek CAS4140 S! amplifier and am impressed with it. It sounds really good and not an IC in sight (all discrete transistor). It even has a switchable MM/MC phono preamp. As it is at least 30 years old, I now intend to replace the electrolytic capacitors and do a general refurb. I have noticed however that when turning the balance pot to each extreme, each silent channel starts making a fluttering sound which I assume means that the amp becomes a bit unstable when that channel's signal is fully earthed by the pot. I have never made much use of a balance control, so I am wondering if it would be worth omitting it altogether. Has anyone got any thoughts. Many thanks.
 
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