How to build the F5

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#621
NP gave all his designs in public ;

anyone thinking that high res pictures at 6moons and few other places are published without his blessings ?

so - if he is certain that 300VA toroid + 8 x 15mF/25V is good enough for 160W of dissipation and 4K of greenies , I have no objection .

that doesn't stop me to use 2 x 250VA or even 2x400VA toroids and (4+4)x 33mF/25V for my Papamp
there is always need for book and calc and some brain ; but sometimes too much of a brain isn't smartest thing to have :rofl:

worst drek gadgets I had "pleasure" to see and/or repair were over-engineered piece of drek , not result of bean-counter's efforts

usually bean-counter engineers are way more capable than spoiled brat ones .

just for illustration - absolutely worst radio production (mix) deck I had opportunity to work with , see and repair - is one made by ( now defunct) local factory , called Lola Audio ; full with Penny Giles , Neutrik , Alps , Philips , etcetera jewels ..... it sounds as drek , works the same , buzz the same ....... ground loops , not enough headroom ......
and I always had a thoughts how decent and clever Studer engineers could make 3 proper decks with same amount of hardware , all whistles and bells included

so - take NP's visible work as shown path - " go , boy - make that better for your self ; I have other ,more important and fun , things to do . "
 
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#622
please note that Panasonic have about a hundred different 25V variations, within the same type, and different prices
the type used in FirstWatt is one the most expencive of those
not at all cheap for a 'consumer' buying just a few
buy a factory box of 500 direct, and its a different price
 
#623
tinitus said:
please note that Panasonic have about a hundred different 25V variations, within the same type, and different prices
the type used in FirstWatt is one the most expencive of those
not at all cheap for a 'consumer' buying just a few
buy a factory box of 500 direct, and its a different price
Click to expand...

I think FW uses Pansonic TSUP series 85C caps. About $3-4 each in small quantities.
 
#624
Me used 25Vdc TSHA Panasonics (105C) in the Alley-J, still seem to hold their liquor (very well vented).
Btw, on really pretty 300VA's from a groupy shag at the German forum, same blue encapsulated ones as used in the Tessendorf power amps.
 
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#627
I can't imagine there would be a lot of difference between two different Panasonic snapins. I think this was discussed in the F5 thread like three years ago. At the time the only 22x50mm 15,000uf cap with 85c rating was one from the TSUP series.
 
#629
jacco vermeulen said:
Hey, i'm Dutch, i shag around.

Ha, but bet you a nickel i can name 15 minimum part numbers, type, manufacturer, source adress of this one : http://www.tessendorf.de/images/classabig.jpg

(speaking of Fuk-U-shima, seen a CRC with Roederstein EY electrolytics and MPC71 metalband resistors before ?)
Click to expand...

now I know why ya Klompenwearing ppl are so wakoo , even your MotoGP is different to all other - sole one running on Saturday ( instead on Sunday , as in other parts of brownie globe ) , so that you are free for early Sunday shag :rofl:

gimme a brake - that's just filthy rich version of MF A1 drek

regarding MPC - every second mediocre wallmart japamp have them ; maybe I must be impressed ?
 
#630
speaking of ....... MPC in CRC :clown:


190261d1286046673-papas-koan-papas-surprise-iec.jpg
 
#636
It did make sense when I wrote it, I swear. I'm not going to pretend I know what I'm doing, thats why I asked 🙂

I was under the impression that wiring the dual secondaries in parallel allowed twice the current delivery at the same voltage. Pass recommends a unit capable of delivery 10A peaks so.......... 1=8 ~ 2=16?

Heeeeeeelp.... I only need to buy the transformers and I can start testing / electrocuting myself ?!?!?!?

cheers
Dean
 
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#637
Doesn't he recommend that peak current for a stereo amp with one transformer? Thus one transformer per channel should be just fine. Just be sure the transformer you use will regulate well so your rail voltage doesn't sag.
 
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#639
you need two secondaries to have symmetric PSU

F5 , in stock form - with 2x18Vac secondaries , will have around +/-22V after rectifier and smoothing caps .

+/-22V means - symmetric PSU , so there is no way that you can use parallel anything .

Papa use ~ 300VA xformer common for both channels , but xformer is of decent quality .

dunno is linked one of same quality , but if you use 2 of them ,there is possibility that they will be fine , even if of lesser quality than FW stuff .

yes - buy them and enjoy .

but - you really need to learn some basics ( how to read schematic , for start) - not to please me or anyone , but to be able to make something ( with help ) , without hasta la vista babe ......
 
#640
"The power supply of the tested amplifier is +/-24 volts and should be rated at 6 amps
continuous duty, and more than 10 amps peak per channel".

I read this as a literal guide and was looking for a toroidal that delivered as such.

Again, I am happy to just use what works, but its going to be cheaper to buy from aus so i need to find the right device on there site.

https://www.tortech.com.au/

Cheers
Dean
 
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