FirstWatt J2

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Rewind

Rewind

Member
Joined 2009
EUVL said:
This is for noobs :
https://diyaudiostore.com/collections/aca-mini

It is not about the soldering, but the debugging in case of trouble.
Build something easy first, save your Semisouths for later projects.


My 2 cents,
Patrick
Click to expand...
I regard myself as the biggest noob on DIYaudio, even if I already completed ACA F5, B1, B1 Triode, and almost there with F6, V-FET N-channel, and ACN. But I can’t keep completing ACAs over and over again.

So you are saying I should save my pair of semisouths for an F8? I must say, I am having impure thoughts about the F8 now that it is no longer in production.
 
chromenuts

chromenuts

Member
Joined 2008
Paid Member
Just curious…I often have my head in the sand (so to speak).

I noticed that Reno HiFi mentioned on their webpage that the J2 is discontinued (I was looking at prices on some items being sold off before they close down for good).

I confirmed the available new column on First Watt page says “N”.

I wondered if there was an official announcement I missed?

I also wondered if Papa was going to release any official circuit into the wild?
 
M

mkc

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Joined 2002
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As tempting as the J2 is it requires a lot of parts that is hard to source. Where as the Aleph-J is somewhat easier although still requires some p-channels. This has made me pondering about an Aleph-J with F8 style input stage. Nelson, have you tried something like that? Perhaps named Aleph-J.5 :unsure:
 
M

mkc

Member
Joined 2002
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Hi Patrick,

I'm familiar with your efforts. I have bought the parts to try it out. However, my thought about the Aleph-J with F8-styile input stage was response to Nelsons comment about bringing something like the J2 to the Diyaudio store. Thinking that such a circuit perhaps would be easier to build. But, perhaps there might not be enough advantages in such a circuit, apart from using only 1 p-channel, compared to the standard Aleph-J. The p-channel can be had for reasonably price through the shop.

Mogens
 
EUVL

EUVL

Member
Joined 2003
xen-audio.com
Aleph-J is different from the J2 in the way the current source is modulated.

The J2 (and F8) modulated current source using the optocoupler is a simpler circuit and has less stability issues.
Putting J2 in the store means putting Semisouth's also in the store.
Unless you use MOSFETs in its place, but it is not a J2 anymore.

And you still need 2SJ74's, which is not an active part.


My 2 cents,
Patrick
 
adason

adason

music soothes the savage beast
Joined 2004
edsaudiopages.blogspot.com
Paid Member
Perhaps stupid question...can cny17 be substituted with 4n35 without any need for bias tweeking?
 

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