F5 power amplifier

This is overkill:eek:

In my first F5 i was using 4x12000 uF per channel. It was dead silent too.

Hi.Nelson uses 120000uf per stereo and most people say that it is casual not perfect.I also made tests with different values and experienced that sound always get better by adding capacitors(Not only get dead silent also for better bass mid and treble performance,better soundstage,better dynamics)
 
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As i see on F5 and other class A amplifiers the more power the better.More pieces of capacitors more powerful transformer.I think 2x300va should be much better

No. Especially for Class A this is not true. There will be always the same current from the power supply. If you oversize your transformer it won´t hurt but it won´t help either. It _could_ deliver more current but never will asked to do so.
 
You know that F5 is a push pull class A amplifier and the bigger transformer will be better for heat dissipation and better ac wave resolution.And also bigger capacitor bank results better ESR parameters and it causes better ripple current and better smooth DC supply
Class A is the best sounding amplifier but sometimes more risky than the other amplifiers so it is better to use bigger supplies too(especially hot countries)
If you have a look at Krell KSA amplifiers (It is push pull class A amp like F5 amp)you can see 1800Va transformers
 
With this obsession that some folks have about using bigger and even 'more bigger' caps in the supply, It might be worth mentioning that each of these big power caps are generally built for specific purposes and only a few are designed specifically for the audio industry, so choosing a size a voltage or an esr doesn't automatically get you a 'better' sound, assuming that 'your better sound' would .......etc.

Example: Rifa don't sound anything like Mundorf, Jensen, F&T, Roe (Vishay), Frako, etc and similarly BHC are quite different to Siemens/Epcos/S&M, and also the theSiemens/Epcos B41550 (Sikorels) are noticeably different to the B41455 (GCs) [old numbers, sorry]

So, the choice of the Type of cap usually has more effect on the 'sound' of your amp than it's size or voltage, assuming it's big enough, naturally!

Also, as Blues said, if you intend running an F5 hard, the supply has to consider the extra classAB demands - unfortunately, it's never simple, but that's the challenge, yes!

Also, as Bear added - Cmultipliers just don't 'fall together' (particularly when matching +/- rails) - often you just trade one thing off for another (dynamics for image, bass for mids, treble ...) and you end up right back where you started!

Transformers have the same variation - my F3 started with a single 300VA for both channels, doubled it to a 300VA/ch, swapped this for a single 500VA with 2 secondaries then built a 450VA EI (with 2 seperate secs), and the F5 now uses the same.
The 2nd (extra) 300va gave more "grunt', but lost some image - the 500va single gave very similar 'grunt' (sorry for the vague terms) and a much better image - the 450va EI (large frame) gave a cleaner sound all over and more precise image and instrument seperation - this is according to my setup and not necessarily the same elsewhere.

Unfortunately, these transformers aren't small or cheap and the BYW diodes, Siemens caps, bipasses, snubbers all add up to quite a bit - however, these amps are worth the effort.


Adding the Cmultis on the F5 seems to just give a bit better all over result when I finally got them to behave. O/P delay relay until each rail Cmx settles down - I couldn't get the TeddyRegs Cmulti (Vbex, or 'gyrator" ?) to 'come good' so didn't continue - not completed yet.

Later, I'll maybe upgrade those Rail Cmxs for better series regulators.
 
Yeah, Bear, I'm a bit off topic about that - sorry.

In a similar way, jackies & umut, the thread of "the best 10,000uF capacitor ..." has good discussion of the properties of various caps - a whole lot of good info there, better than I can do.

No such thread found by search james and since we are discussing the F5 please go ahead and give your opinion on the different caps and there associated sound. here!