F5 increased capacitance

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I am in the beginning stages of an F5 build, next up is power caps.

I have a 600va transformer, any harm in bumping the 8 x 15,000uf caps to say 8 x 22,000uf? the cost difference is not much and they will fit on the board. The caps I am looking at are Panasonic TSUP 35v.

ECO-S1VP223DA Panasonic Electronic Components | Mouser

Will the CL-60 thermistors still be enough or do I need to look at soft start? Planning on running a 35amp bridge.

Also, the Pass schematic specifies 25 volt caps. There's 24 volts on the rails. Wouldn't 35v be a better choice?
 
Official Court Jester
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with 18Vac secondaries , you'll have aroundish 22Vdc under load

if you are not sure how to maintain voltage under 25Vdc during setup procedure , then buy 35Vdc caps

22mF isn't critical ; I'm having 33mF-0R1-33mF on each rail in FW based sort of monoblock (common 800VA xformer , with 4x18Vac )
 
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ApexJr has these 33mF 50V caps for $4 each. Get some Teflon coated wire and some big rubber feet while you're ordering.

For soft start, next time I want to try something with an AC relay like 'Fig. 2' in the attached article.
 

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Zen: That's good to know. I'd rather user the Cl-60 than a softstart board.

Apex Jr. looks like a great shop. I may order some wire from them. Don't know if I am ready to point to point a power supply yet though.

I know it's been done to death but you guys have any opinions on IRF vs Fairchild vs Toshiba outputs? It will be a standard F5, One pair N/P per channel.

I am leaning towards IRFs becasue they are easy to get. The Fairchilds seen to be unobtainium and the Toshibas scare me with the different pin out and possible resistor change needed.
 
Official Court Jester
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best thing after wheel is - soft start circuit but filled with series NTCs , instead of fixed resistors

that will give you really soft start

whatever - that's better in just one instance - behavior in case of mains blackout - when you'll need maybe every 10-th time to change fuse

which Toshibas exactly ?
 
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... Don't know if I am ready to point to point a power supply yet though.
One more shameless plug: ApexJr has these Euro terminal blocks which if used strategically can be very flexible while safely handling large currents (as they're virtually touch-proof when the wires are stripped to the proper length).
And also 5mH 19AWG inductors for CLC...
 
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I have 6 x 47,000uF caps in my F5 and I only use a CL-60, no soft start. Its been working like that for about a year and a half. Gets switched on almost daily, no problems.

You're ok.

As far as transistors I've tried the Fairchilds and the Toshibas. I like the Toshiba more, more "organic" and sweeter sound.
Farichilds are more sterile to me.
 
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Thanks for the info guys. Looks like 22Kuf x8 wont be an issue w/just the CL-60 and no soft start board.

So, I thought the 2SK1530/2SJ201 had a different pinout than the IRF/Fairchild mosfets. If they are the same pinout will they drop into a standard F5 build and bias up with no resistor changes/other changes?

Looks like I can get the Toshibas from Spencer at FET audio and analog metric has them as well. Cost more than the IRF's but could be worth it. Last thing I want to do is build the amp with IRF's and then always wonder if the Toshibas are better. Usually that ends up with me ripping the amp apart about 6 months later to "upgrade".
 
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