Subbing 2SK389 for 2SK170 - diyAudio
Go Back   Home > Forums > Amplifiers > Solid State

Solid State Talk all about solid state amplification.

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 14th April 2008, 05:44 PM   #1
diyAudio Member
 
leadbelly's Avatar
 
Join Date: Dec 2002
Location: Calgary, Alberta
Default Subbing 2SK389 for 2SK170

I don'y really know a whole lot about discrete SS, so here's my question.

I'm looking at building a Pacific phono preamp (schematic attached).

I have both SK170's and SK389's on hand to build it. If I were to sub SK389's into the circuit, would thermal coupling provide more benefits if (a) each SK389 were split across the stereo channels, or (b) each SK389 were split across the 2 stages of a single channel? Or is it not a good idea?
Attached Images
File Type: jpg pacificriaa-1.jpg (36.7 KB, 238 views)
__________________
Aerodynamics are for people who can't build engines. Enzo Ferrari
  Reply With Quote
Old 14th April 2008, 06:39 PM   #2
mlloyd1 is offline mlloyd1  United States
diyAudio Member
 
mlloyd1's Avatar
 
Join Date: Feb 2001
Location: illinois
in my humble opinion, this circuit would not take advantages of the matched characteristics and thermal tracking capabilities of the 2sk389 dual jfet in either of your suggested scenarios. save your 2sk389 parts for a more beneficial application; use the 2sk170 and be happy.


mlloyd1
  Reply With Quote
Old 14th April 2008, 07:22 PM   #3
satoru is offline satoru  United States
diyAudio Member
 
Join Date: Jan 2007
Location: Berkeley, California
Hi leadbelly,

I don't think you want your input and output stage JFETs to be thermally coupled, nor left and right channels. So, better off with 2SK170. More important to pick one with Idss ~ 5mA (that sets the voltage on JFET) that sets the voltage here and there. Good luck!

Satoru
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Group Buy: Linear Systems LSK389 / LSK170 JFETs (i.e. Toshiba 2sk389/2sk170 subs) luvdunhill Group Buys 355 11th September 2014 07:55 AM
SMT replacment for 2SK170/2SK389 AudioAngel Parts 3 18th April 2014 07:28 AM
Building ONO - looking for 2SK170 & 2SK389 skseah Pass Labs 34 7th February 2005 10:19 PM
2sk389, 2sk170, 2sj74 in Europe? giolight Parts 16 6th December 2002 12:28 PM


New To Site? Need Help?

All times are GMT. The time now is 06:33 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2