Power Amp advice needed, for my JBLs 4312 power thirsty...

Yes you could do F5 turbo.

I think a high powered F4 would be nicer assuming the phono preamp outputs 60V rms as you said earlier.

You would need to run it without the input jfets though, unless you're ok doing it on a proto board or making a pcb, in which case a modified circuit could be provided (ie if you needed the jfets at input)

Maybe the best solution would be to use a high quality audio transformer to convert the signal from single ended to balanced then no circuit modifications would be needed, you could make a balanced version of the F4.

Or balanced BA3 without the signal transformers at input

The easiest will be high powered F4 without input jfets

what about Aleph J?
 
easiest way is - find someone close to you with decent 25W amp and try it in your place

decent means - no less that 15kg , whichever class amp is

Aleph J ..... certainly excuisite amp, but not of power champions of FW stable

for champions , look for F4 - you have swing from preamp , so first box ticked

and you can always make another one, feed it balanced and there you go - 100W monoblcoks
 
The 2 best options are (not in any order)
1) High powered F4 with out input jfets
2) Balanced F4 (requires the addition of cheap signal transformer)

Zenmod can suggest best transformer for the balanced version.
Maybe cinemag or jensen


🙂

Actually do what Zenmod said. Just build a stock F4 then if you need more power then go balanced to get you to 100W.
 
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The 2 best options are (not in any order)
1) High powered F4 with out input jfets
2) Balanced F4 (requires the addition of cheap signal transformer)

Zenmod can suggest best transformer for this.
Maybe cinemag or jensen


🙂

easiest way is - find someone close to you with decent 25W amp and try it in your place

decent means - no less that 15kg , whichever class amp is

Aleph J ..... certainly excuisite amp, but not of power champions of FW stable

for champions , look for F4 - you have swing from preamp , so first box ticked

and you can always make another one, feed it balanced and there you go - 100W monoblcoks

thank you sir, now I see what you mean...
so perhaps even an F4 with normal 25V rails could do the job, and in the end, if necessary, two monoblocks...

By leaving the input jfets (I undertand, i use swing from preamp) i should make schematics changes that I'm not really aware of
 
buy S/H Treshold from Papa's era and that's it

better that way than going DIY just to have an amp, perfect recipe for struggle

your Marantz is a piece of Drek, comparing to any of FW format amps, not just in Verity but also power

man replaced his Audiophool Series Marantz 100W/ch amp with my Babelfish M25, for driving his Dynaudio Contour (first 1.3 then 1.8) and never looked back

go figure

sorry, just because it's monday and i feel I need to laugh, what's fw format ?
And... could you elaborate shortly why the marantz is a piece of Trek
Thanks 😀
 
decide what you want and we'll help along

though, with your eeny 2K5 for Rout of toob preamp , better to leave F4 input buffer in place

don't forget - your're making of the best amps in that power range, skimping 50 bucks for input JFets is not big save

and, btw. you're having Gianluca's Modushop practically in neighborhood

Forza Vale!
 
First Watt format factor - all of them being in same case, dictating max possible dissipation

why is Marantz piece of Drek ?

is it on pair with Diego Nardi's preamps ? I don't think so ........ venerable piece of Drek

it was as new commercial mid-range of products, not any sort of High End ....... and we Audiophools gave them golden glitter with years
 
First Watt format factor - all of them being in same case, dictating max possible dissipation

why is Marantz piece of Drek ?

is it on pair with Diego Nardi's preamps ? I don't think so ........ venerable piece of Drek

it was as new commercial mid-range of products, not any sort of High End ....... and we Audiophools gave them golden glitter with years

is there a bom source here in europe for pcb, transofrmers, cases?
 
First Watt format factor - all of them being in same case, dictating max possible dissipation

why is Marantz piece of Drek ?

is it on pair with Diego Nardi's preamps ? I don't think so ........ venerable piece of Drek

it was as new commercial mid-range of products, not any sort of High End ....... and we Audiophools gave them golden glitter with years

my friend, i guess i need now a babelfish m25, seems like a plain f4 is for sissies ? 😀
 
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