Simplest class B Amplifier

PicancoNet · 2nd June 2005, 01:13 AM

Anyone has a simple Class B Amplifier ?

Leolabs · 2nd June 2005, 04:13 AM

What for?????

Duo · 2nd June 2005, 04:17 AM

I do have some very simple class B ideas.

If you want extreme simplicity, I suggest an opamp and diode biased output stage. This can be accomplished with a minimal amount of components and operate with fair audio quality at low distortion if done properly.

PicancoNet · 2nd June 2005, 05:57 AM

I want a simple audio amplifier with discret components.

The input stage can be a op-amp.

amplifierguru · 2nd June 2005, 06:20 AM

Here you are then.

Still leaves room for embellishment. RtoR. Good for sub.

AndrewT · 2nd June 2005, 07:40 AM

Hi Amplifierguru,
Looks like a CFP using FETs
Should the Vgs +Rs be fed from the Vce of the driver?
or from a resistor in the collector supply of the driver?
How does the VAS determine it's voltage gain? There is no feedback resistor, just a 330p cap. Or is it 4k7/100r? Seems a bit large @ times 47.

rintek · 2nd June 2005, 02:10 PM

Simplest class B Amplifier Post #1
Anyone has a simple Class B Amplifier ?

http://www.angelfire.com/ab3/mjramp/amp7.html

Miles Prower · 2nd June 2005, 09:38 PM

Anyone has a simple Class B Amplifier ?

Here, they don't come any simpler than this. Here is part of the audio strip for a longwave receiver I designed and built awhile ago. Pay attention to the final that is connected to the active CW filter.

Works just great for this application. Of course, as for audio quality:

Then, again, high fidelity is neither needed nor desireable in this application.

Edit: Forgot a decimal point. The emitter resistors are 1.0/1.0W, not 10 ohms.

Duo · 3rd June 2005, 12:15 AM

Lol, the PNP transistor in the push-pull output stage on that CW radio amplifier is in backwards.

By changing that amplifier to work with negative global feedback, it would be not bad.

Duo · 3rd June 2005, 01:04 AM

Here's a design of great simplicity that I've used in a lot of projects when I needed a quick amplifier.

If you like, I can show you one with even more simplicity that uses three transistors, however, it's nowhere near as nice as the one I've shown here.

(NOTE) The input cap is 2.2µF. I guess if you want a better low roloff you could put 22µF lol.

2nd June 2005, 05:57 AM	#4
PicancoNet diyAudio Member Join Date: Jan 2004 Location: Rio de Janeiro, RJ	I want a simple audio amplifier with discret components. The input stage can be a op-amp. __________________ Sounds Goods

2nd June 2005, 07:40 AM	#6
AndrewT diyAudio Member Join Date: Jul 2004 Location: Scottish Borders	Hi Amplifierguru, Looks like a CFP using FETs Should the Vgs +Rs be fed from the Vce of the driver? or from a resistor in the collector supply of the driver? How does the VAS determine it's voltage gain? There is no feedback resistor, just a 330p cap. Or is it 4k7/100r? Seems a bit large @ times 47. __________________ regards Andrew T.

2nd June 2005, 02:10 PM	#7
rintek diyAudio Member Join Date: Jun 2004 Location: universe	Simplest class B Amplifier Simplest class B Amplifier Post #1 Anyone has a simple Class B Amplifier ? http://www.angelfire.com/ab3/mjramp/amp7.html

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
ISO "Simplest" possible amplifier	dano12	Solid State	32	27th February 2009 11:07 PM
Simplest class D ever	Rikard Nilsson	Class D	3	9th November 2008 08:09 PM
simplest amplifier possible with BJT's?	rmgvs	Solid State	123	10th July 2008 04:05 AM
LM3886 GC - "Simplest Ever Amplifier Bridging"	jweber	Chip Amps	20	18th June 2006 03:55 AM

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


<a rel='nofollow' href='http://www.diyaudio.com/openx/www/delivery/ck.php?n=aa5cb2e9&cb=358004' target='_blank'><img src='http://www.diyaudio.com/openx/www/delivery/avw.php?zoneid=3&cb=358004&n=aa5cb2e9' border='0' alt='' /></a>	We're saving for a new server - help us to serve you by Donating Today and become a friend with benefits! Ads on/off / Custom Title / 2009 Tshirt / More PMs / Bigger Images / Advanced printing

2nd June 2005, 01:13 AM	#1
PicancoNet diyAudio Member Join Date: Jan 2004 Location: Rio de Janeiro, RJ	Simplest class B Amplifier Anyone has a simple Class B Amplifier ? __________________ Sounds Goods

2nd June 2005, 04:13 AM	#2
Leolabs diyAudio Member Join Date: Dec 2004 Location: Bukit Mertajam	What for?????

2nd June 2005, 04:17 AM	#3
Duo diyAudio Member Join Date: Jun 2002 Location: Planet Earth	I do have some very simple class B ideas. If you want extreme simplicity, I suggest an opamp and diode biased output stage. This can be accomplished with a minimal amount of components and operate with fair audio quality at low distortion if done properly.

3rd June 2005, 12:15 AM	#9
Duo diyAudio Member Join Date: Jun 2002 Location: Planet Earth	Lol, the PNP transistor in the push-pull output stage on that CW radio amplifier is in backwards. By changing that amplifier to work with negative global feedback, it would be not bad.

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