Simple Class A with 2SA1943/2SC5200

john65b · 12th April 2011, 12:12 PM

Hey all,

Anyone know of a ultra simple F5-ish Babozen type circuit (Zen V5 with JFet front end) for the Toshiba 2SA1943/2SC5200? Balanced input would be great, but SE is OK...

Looking at using 2SK170/2SJ74 for the input, so rails would be around 20V. Not looking for lots of power...yet...

I know the JLH and Le Monstre, but wondering about using these two Jfet/transistor arrangement...

lineup · 12:40 PM

You could build Le Monstre, using a 2x12VAC trafo.
This makes the amplifier have ~2X16VDC rails.
Then set Class A bias current to like 1A for 8 Ohms speakers.

See the Le Monstre thread where I posted an example schematic tested with SPICE.
For 2X16 V
Hiraga "le monstre"

Bigun · 12th April 2011, 01:33 PM

The Le Monstre is a great starting point from what I've read. You could redesign it a little if needed - I had a paper design in which the front end, which in Le Monstre are cascoded JFETs, was a pair of biassed complimentary BJTs. I called it Le Petit Monstre

john65b · 12th April 2011, 01:43 PM

Yes, this will do it...while not as simple as Babozen (need additional transistors and parts) its still quite simple...how does it sound?

lineup · 12th April 2011, 02:04 PM

Original Monster has got 12 volt rails. But no problem run 16 Volt.
A couple of questions:
- do you have BL or GR of 2SK170/SJ74 ?
- do you intend to use 4 Ohm or 8 Ohms speakers

How it sounds?
I think good. Those who built it loves Le Monstre.

john_ellis · 24th April 2011, 08:46 PM

Hi
Yout might like to see the circuit in my "simple class A" thread. It's currently using 2SC5200 and 2SA1943 in the first prototype.
John

12th April 2011, 12:12 PM	#1
john65b diyAudio Member Join Date: Jan 2005 Location: Chicago	Simple Class A with 2SA1943/2SC5200 Hey all, Anyone know of a ultra simple F5-ish Babozen type circuit (Zen V5 with JFet front end) for the Toshiba 2SA1943/2SC5200? Balanced input would be great, but SE is OK... Looking at using 2SK170/2SJ74 for the input, so rails would be around 20V. Not looking for lots of power...yet... I know the JLH and Le Monstre, but wondering about using these two Jfet/transistor arrangement... __________________ "I speak Spanish to God, Italian to Women, French to Men, and German to my Horse" - Charles V

12th April 2011, 12:34 PM	#2
lineup diyAudio Member Join Date: Dec 2005 Location: the north	You could build Le Monstre, using a 2x12VAC trafo. This makes the amplifier have ~2X16VDC rails. Then set Class A bias current to like 1A for 8 Ohms speakers. See the Le Monstre thread where I posted an example schematic tested with SPICE. For 2X16 V Hiraga "le monstre" __________________ lineup Last edited by lineup; 12th April 2011 at 12:40 PM.

12th April 2011, 01:33 PM	#3
Bigun diyAudio Member Join Date: Jan 2009 Location: K-W Ontario Blog Entries: 2	The Le Monstre is a great starting point from what I've read. You could redesign it a little if needed - I had a paper design in which the front end, which in Le Monstre are cascoded JFETs, was a pair of biassed complimentary BJTs. I called it Le Petit Monstre __________________ "The test of the machine is the satisfaction it gives you. There isn't any other test. If the machine produces tranquility it's right. If it disturbs you it's wrong until either the machine or your mind is changed." Robert M Pirsig.

12th April 2011, 01:43 PM	#4
john65b diyAudio Member Join Date: Jan 2005 Location: Chicago	Yes, this will do it...while not as simple as Babozen (need additional transistors and parts) its still quite simple...how does it sound? __________________ "I speak Spanish to God, Italian to Women, French to Men, and German to my Horse" - Charles V

12th April 2011, 02:04 PM	#5
lineup diyAudio Member Join Date: Dec 2005 Location: the north	Original Monster has got 12 volt rails. But no problem run 16 Volt. A couple of questions: - do you have BL or GR of 2SK170/SJ74 ? - do you intend to use 4 Ohm or 8 Ohms speakers How it sounds? I think good. Those who built it loves Le Monstre. __________________ lineup


	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

24th April 2011, 08:46 PM	#6
john_ellis diyAudio Member Join Date: Sep 2006	Hi Yout might like to see the circuit in my "simple class A" thread. It's currently using 2SC5200 and 2SA1943 in the first prototype. John

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)

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
2sc5200 and 2sa1943?	adobetoo	Solid State	3	27th March 2011 08:46 AM
2sc5200/2sa1943	stth15r06	Solid State	4	15th March 2011 10:17 AM
2SC5200 / 2SA1943 Looking	funky2x	Solid State	11	15th March 2011 10:14 AM
LME49810 with 2sa1943 and 2sc5200	xeclipse	Solid State	12	15th July 2010 03:35 PM
class A amp using 2sc5200/2sa1943 or 2sa2922/2sa1612	space2000	Pass Labs	1	21st June 2008 05:36 PM

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