tube power supply

MiiB · 27th February 2008, 10:01 AM

I am currently working on a solid state amplifer. I have seperated the powersupplies for the voltage and current stage. I would like to make a chokeloaded and tube rectified power supply for the voltage gainstages. Can anyone help me with a generic design to a +/- 50 V power supply with tube rectification and Choke loading.

Colt45 · 27th February 2008, 10:19 AM

ugh why?

50v.. and tons of current, right? how much exactly?

low voltage and tons of current aren't exactly what tubes excel at... it can be done, but it will be a big abortion most likely.

edit: nevermind, noticed you mentioned just for the gain stages. Anyways, how much current, how much regulation.. etc. This really is a SS job, though.

MiiB · 27th February 2008, 10:55 AM

As mentioned this supply is just for the gainstages so the current needed i very little, less than 200mA. So I cant see that as a problem.

The reason is that I have a DAC with an IV stage that runs on single supply. Here the tube rectification and choke loading is a tremendous improvement adding an ubeliveable black background and expanding the sound stage tremendously. So speakers littraly fill the room.

tubetvr · 27th February 2008, 12:27 PM

The only difference between a tube power supply and a solid state one that can make a difference in your case is the absence of switching noise in the tube supply. My suggestion is therefore to design a solid state supply optimised for low switching noise using soft recovery diodes and snubbers together with additional filtering it will be as good as the tube power supply. I have upgraded the power supply in my DAC with measureable results and I alos believe I can hear an improvement. I also design all solid state supplies for tube amplifiers in a similar way.

Regards Hans

MiiB · 27th February 2008, 05:17 PM

the switching noise is still present with softrecovery diodes. Hence the desire for tube rectification. I throughly belive that a good way to proceed.

JoshK · 27th February 2008, 05:57 PM

Does it strictly need to be a bipolar supply? It can be done a number of ways, but you'll find more prior art with single supplies. The best advice I can give you is to read up a bit on tubecad.com. He has numerous examples of such supplies, both singular and bipolar. Then download PSUDII on duncanamps.com and play around.

tubetvr · 28th February 2008, 05:13 AM

Quote:

the switching noise is still present with softrecovery diode

Then your snubber circuits are not good enough, optimise the snubber according to what is written here http://www.hagtech.com/pdf/snubber.pdf and the switching noise is gone.

Regards Hans

ray_moth · 28th February 2008, 05:39 AM

200 mA is still quite high for a tube PS, considering that it will be continuous. One thing you might like to consider trying is a pair of thermionic TV damper diodes in a hybrid bridge together with a pair of good SS diodes. This arrangement will suppress any noise from the SS diodes.

Dampers are pretty rugged and a pair of 6D22S would do a good job. You need 6.3 v @ 3.8 A to heat a pair of them and they use magnoval sockets (like a giant B9A) which are usually available from the tube vendor.

How you organize the filter depends on the input and output voltage requirements. A choke input filter, which should be quieter, will give 0.9 x the RMS input voltage; a capacitor input filter will give up to 1.4 x, depending on the load. If you go for a cap input, don't exceed 50uF or the 6D22S may suffer.

Ryssen · 28th February 2008, 09:05 PM

How meny volts will the 6D22S "eat"?

ray_moth · 29th February 2008, 01:27 AM

Quote:

How meny volts will the 6D22S "eat"?

In my experience, about 15v driving a Stereo EL34 PP amp with total current consumption of about 250 mA including all stages.

27th February 2008, 10:01 AM	#1
MiiB diyAudio Member Join Date: May 2005 Location: Denmark	tube power supply I am currently working on a solid state amplifer. I have seperated the powersupplies for the voltage and current stage. I would like to make a chokeloaded and tube rectified power supply for the voltage gainstages. Can anyone help me with a generic design to a +/- 50 V power supply with tube rectification and Choke loading.

28th February 2008, 09:05 PM	#9
Ryssen diyAudio Member Join Date: Dec 2003 Location: Sweden--> Here	How meny volts will the 6D22S "eat"? __________________ Regards Åke

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
Power Supply Module for Tube Amp	gijoe_22	Vendor's Bazaar	8	16th December 2009 02:25 PM
Tube power supply	duderduderini	Tubes / Valves	1	9th December 2008 04:33 AM
323 A tube power supply design	pjwd	Power Supplies	0	20th August 2008 08:48 AM
Tube power supply for TT	Miniwatt	Analogue Source	1	8th March 2005 06:49 PM
Power Supply and VR tube help!	AudioGeek	Tubes / Valves	24	28th February 2004 12:16 AM

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

27th February 2008, 10:19 AM	#2
Colt45 diyAudio Member Join Date: Feb 2002 Location: Canada	ugh why? 50v.. and tons of current, right? how much exactly? low voltage and tons of current aren't exactly what tubes excel at... it can be done, but it will be a big abortion most likely. edit: nevermind, noticed you mentioned just for the gain stages. Anyways, how much current, how much regulation.. etc. This really is a SS job, though.

27th February 2008, 10:55 AM	#3
MiiB diyAudio Member Join Date: May 2005 Location: Denmark	As mentioned this supply is just for the gainstages so the current needed i very little, less than 200mA. So I cant see that as a problem. The reason is that I have a DAC with an IV stage that runs on single supply. Here the tube rectification and choke loading is a tremendous improvement adding an ubeliveable black background and expanding the sound stage tremendously. So speakers littraly fill the room.

27th February 2008, 12:27 PM	#4
tubetvr diyAudio Member Join Date: Jan 2003 Location: Now back in Sweden	The only difference between a tube power supply and a solid state one that can make a difference in your case is the absence of switching noise in the tube supply. My suggestion is therefore to design a solid state supply optimised for low switching noise using soft recovery diodes and snubbers together with additional filtering it will be as good as the tube power supply. I have upgraded the power supply in my DAC with measureable results and I alos believe I can hear an improvement. I also design all solid state supplies for tube amplifiers in a similar way. Regards Hans

27th February 2008, 05:17 PM	#5
MiiB diyAudio Member Join Date: May 2005 Location: Denmark	the switching noise is still present with softrecovery diodes. Hence the desire for tube rectification. I throughly belive that a good way to proceed.

27th February 2008, 05:57 PM	#6
JoshK diyAudio Member Join Date: May 2004 Location: Toronto, ON	Does it strictly need to be a bipolar supply? It can be done a number of ways, but you'll find more prior art with single supplies. The best advice I can give you is to read up a bit on tubecad.com. He has numerous examples of such supplies, both singular and bipolar. Then download PSUDII on duncanamps.com and play around.

28th February 2008, 05:39 AM	#8
ray_moth diyAudio Moderator Emeritus Join Date: Jan 2004 Location: Jakarta	200 mA is still quite high for a tube PS, considering that it will be continuous. One thing you might like to consider trying is a pair of thermionic TV damper diodes in a hybrid bridge together with a pair of good SS diodes. This arrangement will suppress any noise from the SS diodes. Dampers are pretty rugged and a pair of 6D22S would do a good job. You need 6.3 v @ 3.8 A to heat a pair of them and they use magnoval sockets (like a giant B9A) which are usually available from the tube vendor. How you organize the filter depends on the input and output voltage requirements. A choke input filter, which should be quieter, will give 0.9 x the RMS input voltage; a capacitor input filter will give up to 1.4 x, depending on the load. If you go for a cap input, don't exceed 50uF or the 6D22S may suffer.

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