J-JLH or PLH-J ?

drjbf1 · 12th April 2010, 09:47 AM

In the PLH article Nelson says:

"If you send me a bag of high power Jfets, I’ll supply a schematic that will work with them, too."

Has anyone seen such a schematic?

flg · 12th April 2010, 11:55 AM

Only the "simplified" J2 as far as I have seen...

Nelson Pass · 12th April 2010, 09:59 PM

I had forgotten that I made such a promise. It is, however
very do-able. All you have to do is send me that bag. I
cannot be expected to supply the high power Jfets as well...

Blues · 12th April 2010, 10:13 PM

Circuit should be reserved for the PL custom power jfets

Maybe the color green will make it get to the production line sooner...

FYC · 13th April 2010, 01:07 PM

A step forward at least, is to replace the input IRF610 with a J-FET. I've done that and I do see an improvement. As a matter of fact, I put 2 2SK147 in parallel as the input stage in place of the IRF610.

Nelson Pass · 13th April 2010, 08:32 PM

I have not tried it yet, but I would expect interesting results
with the SJEP170R550.

tmblack · 18th July 2011, 09:31 PM

How would one make a PLH with a dual power supply?
In the article that was left as a future exercise.

tmblack · 18th July 2011, 09:32 PM

Quote:

Originally Posted by FYC

A step forward at least, is to replace the input IRF610 with a J-FET. I've done that and I do see an improvement. As a matter of fact, I put 2 2SK147 in parallel as the input stage in place of the IRF610.

How would the circuit change if any with the input J-FET ?

flg · 18th July 2011, 09:45 PM

Quote:

Originally Posted by tmblack

How would one make a PLH with a dual power supply?
In the article that was left as a future exercise.

The Class-A Amplifier Site Here you will find at least one version like that

sheep · 19th July 2011, 06:43 PM

I'll work on the latest JLH dual supply version with power BJT's as I have a large supply and they are much cheaper. I'll add the current sources using DM2540 depletion FETS though.

12th April 2010, 09:47 AM	#1
drjbf1 diyAudio Member Join Date: Jun 2007	J-JLH or PLH-J ? In the PLH article Nelson says: "If you send me a bag of high power Jfets, I’ll supply a schematic that will work with them, too." Has anyone seen such a schematic?

12th April 2010, 11:55 AM	#2
flg diyAudio Member Join Date: Jul 2005 Location: North East	Only the "simplified" J2 as far as I have seen... __________________ “Be who you are and say what you feel because those who mind don't matter and those who matter don't mind.” Dr. Seuss

12th April 2010, 10:13 PM	#4
Blues Lightning In A Bottle diyAudio Member Join Date: Sep 2003 Location: The Milky Way	Circuit should be reserved for the PL custom power jfets Maybe the color green will make it get to the production line sooner... __________________ Leap into the Warpspeed wormhole... http://www.6moons.com/audioreviews/warpspeed/1.html

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Plh	Nelson Pass	Pass Labs	192	22nd April 2013 07:57 PM
PLH vs ???	MikeW	Pass Labs	18	8th November 2005 02:06 AM


	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

12th April 2010, 09:59 PM	#3
Nelson Pass The one and only Join Date: Mar 2001	I had forgotten that I made such a promise. It is, however very do-able. All you have to do is send me that bag. I cannot be expected to supply the high power Jfets as well...

13th April 2010, 01:07 PM	#5
FYC diyAudio Member Join Date: Jan 2001 Location: Hong Kong	A step forward at least, is to replace the input IRF610 with a J-FET. I've done that and I do see an improvement. As a matter of fact, I put 2 2SK147 in parallel as the input stage in place of the IRF610.

13th April 2010, 08:32 PM	#6
Nelson Pass The one and only Join Date: Mar 2001	I have not tried it yet, but I would expect interesting results with the SJEP170R550.

18th July 2011, 09:31 PM	#7
tmblack diyAudio Member Join Date: Jan 2005 Location: UK	How would one make a PLH with a dual power supply? In the article that was left as a future exercise.

19th July 2011, 06:43 PM	#10
sheep diyAudio Member Join Date: May 2011	I'll work on the latest JLH dual supply version with power BJT's as I have a large supply and they are much cheaper. I'll add the current sources using DM2540 depletion FETS though.

New To Site?	Need Help?
Register to Participate Search Privacy Statement Contact Us	Frequently Asked Questions Did you forget your password? Mark Forums Read