Jump to content

The Ultimate DIY Part 2 ? The KGITSOJC


kevin gilmore

Recommended Posts

  • 1 month later...

They are either liars, or completely incompetent or both.

4 years to make a p-channel jfet, yeah right.

Or there are huge quantities of 2sk389 and 2sj109 somewhere

that none of us have access to that are preventing lsj109

from being released. Ayre evidently has 10's of thousands

of parts in stock, yet stax had to resort to glueing singles

together recently. Even the singles are not available.

Link to comment
Share on other sites

I'm tempted to ask Fairchild how many parts we need to order to get them matched in a single envelope... 

 

If it meant being able to have available parts to design and build new circuits I would be willing to buy a fair amount of them myself. 

 

Is there no one that makes a decent SMD part that is equivalent to what is needed.  It seems that everyone is going SMD now.  I would hope they could make some good parts in those packages.

Link to comment
Share on other sites

here is the unbalanced/balanced to balanced front end.

 

http://gilmore.chem.northwestern.edu/ubaltobald.pdf

 

really sweet sounding.  0 db of gain balanced, -6db of gain unbalanced.

 

gain is controlled by R5,R32 so i could put a relay in that switches

the gain to maintain 0db (or any other number) when you switch

from unbalanced to balanced.

 

still even better with the that340 replaced with jfets.

mpsw06,mpsw56 replace 2sc2240/2sa970 when we can't get them.

Edited by kevin gilmore
Link to comment
Share on other sites

This is instead of the multiamp board.
Input switching
This board
Pot of some kind
Diamond buffer output

 

There is nothing wrong with the multiamp, in fact it sounds great too.

But the input impedance is lower due to supersymmetry.

 

The idea on all of these is to eventually replace with jfets once

they become available. As it is, this new board is without feedback

of any kind, and is faster and more quiet. plus gain is a single resistor

and compensation is unnecessary.

Edited by kevin gilmore
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.