Dreaming of a DIY power amp

[Dennis Hui]

I'm not familiar with the SP9 so I looked it up. With 20dB gain at line level and
can do 50V RMS output, it can definitely drive the F4 well.

The part William suggested is good and avoids a potential problem, especially
if you might not be able to select parts that operate in a specific range.

 

[Giovanni1968]

Ciao William, thanks for the hint, I will start and take note of all of it all, good to know about the TL431, found this as per your recommendation and right now I got email from the guy who builds and sells the cases here in Italy, I would like to make a full parts list to figure the total cost.

Grazie again

 

[mvaldes]

Ciao Giovanni,
long time ago I start thinking to build a power amp just for fun.
I started collecting all parts to build an M2 and finally couple month ago I was ready to build it.
I was not in hurry because there was a subdole doubt that was obsessing me
Why am I building a so small power amp? It is only 25w....how can it drive my big JBL 4430 ? How can it drive them better than my McIntosh MC252 ?
I finished to assemble the M2 but let it lying on the floor for some days...
Finally I hook the speaker to my diy M2 and start listening some music and....WOW...

To cut the story short, since that moment I never changed back to my McIntosh. I never felt shortage of power and, most important of all, I never listened music from my system like now

 

[Giovanni1968]

Ciao Giovanni,
long time ago I start thinking to build a power amp just for fun.
I started collecting all parts to build an M2 and finally couple month ago I was ready to build it.
I was not in hurry because there were a subdole doubt that was obsessing me
Why am I building a so small power amp? It is only 25w....how can it drive my big JBL 4430 ? How can it drive them better than my McIntosh MC252 ?
I finished to assemble the M2 but let it lying on the floor for some days...
Finally I hook the speaker to my diy M2 and start listening some music and....WOW...

To cut the story short, since that moment I never changed back to my McIntosh. I never felt shortage of power and, most important of all, I never listened music from my system like now

Oh well Michele, I won't mind helping you get rid of the MC252 neither to come give a look (yes, a look because those are so beautiful and such good memories of old times) and a ride to your 4430; I remember as a teen when going to the gym at the base of a local hotel the son of the owner had two 4430 staged by the lobby, the family left the island long time ago but the JBL are still here in a storage, I keep asking the only strict member of the family to check them for me but he says the aunt, owner of the storage, won't allow him to take them :-(

If 25W can drive the 4430 it should be pretty easy to deal with my L220 and give a thrill to the 4311b whose I won't get rid of.

I am getting thrilled at the idea of building something, as an acquaintance once told me "change is always good" and for a status quo person like me that really is a big change even tho if just in a very early stage

So nice to read locals attending the forum

 

[peppennino]

Giovanni,
I made an updated BOM at Mouser.it a few weeks ago, but you have to consider the customs fees because shipping is from USA. Also RS in Italy has good part of the BOM. Better begin by taking the transistor kit and Jfets (too much fakes on eBay) and obviously the PCBs from Diyaudio Shop.

Ciao,
Vincenzo

(Peppennino is a "pupo", a Sicilian puppet -a kid- in the "Intermezzi" of the famous "Opera dei Pupi" from Palermo)

 

[Giovanni1968]

Giovanni,
I made an updated BOM at Mouser.it a few weeks ago, but you have to consider the customs fees because shipping is from USA. Also RS in Italy has good part of the BOM. Better begin by taking the transistor kit and Jfets (too much fakes on eBay) and obviously the PCBs from Diyaudio Shop.

Ciao,
Vincenzo

(Peppennino is a "pupo", a Sicilian puppet -a kid- in the "Intermezzi" of the famous "Opera dei Pupi" from Palermo)

Ciao Vincenzo,

sorry for misunderstand about your name/nickname, I learnt two more things tonight, about the pupo and what a BOM is would you mind share it with me?

Where in Sicilia? I am a couple hundred miles almost straight north of your beautiful island, if earth was flat I could try and spot you tomorrow from the Augustus Gardens and my 600mm scope...

 

[peppennino]

Why am I building a so small power amp? It is only 25w....how can it drive my big JBL 4430 ?

Wow, Michele... 4430 are an old dream, since I saw them in John Cusack's home in "High Fidelity" movie.
Complimenti!

[EDIT] Giovanni, Palermo is just in front your beautiful Island, I live very close to it, near Monreale

 

[Attila I]

@peppennino; Quote:
I made an updated BOM at Mouser.it a few weeks ago, but you have to consider the customs fees because shipping is from USA. ....

hey peppennino,

Mouser does also ship from Munich/Germany -> Mouser.de

have a nice amp
A.

 

[peppennino]

Thanks, Attila! So, are products located in Germany?

 

[Zen Mod]

to my knowledge, even when you're buying through european mouser site, you still need to pay some duties on top of price shown on page, with package receive

?

 

[peppennino]

Mousetr .IT works in that way, ZM

 

[Zen Mod]

so that's it - some import duties and IVA, simply because goods origin is out of EU

 

[Attila I]

they only add sales tax on the bill
most parts are not made in EU and
I don't pay import-tax for resistors or caps
from mexico or india or wherever.



cheers A.

 

[mvaldes]

I usually order from mouser.it but they ever ship from US
If order is higher than 50€ then shipping is free of charge.
Shipping terms are DDP so duty, custom fees and VAT (IVA) are paid by Mouser.

 

[fabrice63]

I usually order from mouser.it but they ever ship from US
If order is higher than 50€ then shipping is free of charge.
Shipping terms are DDP so duty, custom fees and VAT (IVA) are paid by Mouser.

This is the same here is France , everything comes from the US


.

 

[Giovanni1968]

Good day,

after almost a year the decision had been taken and the F4, as many suggested, in on build, not me but my friend Ciro, boards + MOSFETS, case (black with 10mm front panel), transformers (2 x 300VA) and caps (2 x 4 rails) are there, now it's about other active/passive components and refinements before it reaches final stage, in another thread about the F4 I asked advise on such stuff as to avoid bumps and other stuff I might not be aware of but I am pleased and thrilled at the same time to hear what 25W can do with the old L220.

My friend with the fancy setup (Sonus Faber, Jeff Rowland and so on) is biased on Class D and 1/2 KW (!!!) output to drive those little things but I would love to proof him wrong

 

[mvaldes]

Hi Giovanni, welcome on board. I don't know F4 but for sure you will be pleased with this amp.
As I already wrote I've an M2 and I'm very happy with this one. But since I'm very curios I'm now collecting parts for an Aleph 30 and an F6.
Moreover I'm also thinking to make a small system for my bedroom because I've a couple of Sonus Faber Minima FM2 bought about 30 years ago and that are sitting in a closet since almost 20years. I'll make and ACA and ACP+ for them.
We'll see...

 

[Giovanni1968]

Buongiorno @mvaldes, grazie for your reply, on the Italian forum I am subscribed to I obviously get biased replies, they all party for a certain kind of amp they did own which is fine, what I don't understand is the rejection or disregard of something they have no direct experience about, some say "old JBLs need loads of Watts" or "you need BJT based amp" but when I ask if they ever tested the same or similar speakers with something like a First Watt then no reply and when I reply, from my very little knowledge, that Watts is not everything as well as MegaPixels isn't (I am a passionate photographer where the same debates go over and over about quantity vs quality) then silence goes by...

I am almost on the idea to get rid of my beloved JBL 4311b which I bought as a teen and then, later on, get a couple of bookshelves to clear some room but in the meantime I am eager to experience Mr Pass's A Class and have my friend who drives his SF Electa Amator with 350 Class D Watts to rethink the Wattage criterion

Grazie again for all of your kind replies and support

 

[mvaldes]

Giovanni, if it happen that you are traveling in north est area, you are very welcome to come here to see how a 25w class A can drive a big JBL 4430.

Michele

 

[Giovanni1968]

Ciao Michele,

I do really appreciate your invitation but dunno how good of an idea that would be, I mean, big JBL = big tease ;-)

Here where I live, in the gulf of Naples, I recall, as a teen, in a hotel lobby a couple of the same speakers, they are still somewhere in a storage here but the brother of the owner who I keep asking can't find them out, they are probably gone but it would be great fun to restore them.

Glad to read that 25W does a good job on those