Aleph2 PSU questions

Penguin · 24th August 2001, 02:17 AM

Hi,

What is the voltage drop on the PSU when it is loaded with the rest of the circutry. To get the rails to 45 VDC unloaded you need to use a 33V [(Vrms+1.4)*sqrt2] transformer. But is it enough? I am thinking about getting a pair of 500VA torroids from Piltron and they do have 33V secondaries. Would increasing the PSU capacitance decrease the voltage drop?

dee
;-D

GRollins · 24th August 2001, 03:16 AM

Dee,
I'd recommend going for 750 VA, minimum (I've got 1000VA Plitrons on my Aleph 2s, filched from an unfinished project--still need to order proper transformers for the Alephs). 500 VA would be cutting it a bit thin. The 45V rail isn't unloaded--it's going to have to deliver 3A or so at that voltage, and that's at idle. If you pull back too much, the rail will drop, and the transformer will tend to run hot.

Grey

Penguin · 24th August 2001, 03:26 AM

Thanks Grey,

I was just doing some calculating before jumpin' in both feet. Is 33Vs enough or jum to 35V? Going to the 1.5KVA puts you in the 38V minimum output which vould yield a 55VDC unloaded output. How much would the load pull that down? 10%?

dee
;-D

Penguin · 25th August 2001, 01:34 PM

Most informative

dee
;-D

tortello · 25th August 2001, 06:46 PM

Hi,
you can find a good PSU software from Duncan's:

http://www.duncanamps.com/

It works fine, I think.

Penguin · 25th August 2001, 11:22 PM

thanks, Now i just have to figure out the loa on the PSU. Has anybody actually measured the Aleph 2 load on the PSU is it really 3.3 A per side?

dee
;-D

GRollins · 27th August 2001, 12:08 AM

More like 3A per side.
I run mine a little hotter, simply because I can get away with it. The water-cooled system I use can dissipate the extra heat easily.

Grey

24th August 2001, 03:26 AM	#3
Penguin diyAudio Member Join Date: Aug 2001 Location: Baltimore	PSU Thanks Grey, I was just doing some calculating before jumpin' in both feet. Is 33Vs enough or jum to 35V? Going to the 1.5KVA puts you in the 38V minimum output which vould yield a 55VDC unloaded output. How much would the load pull that down? 10%? dee ;-D

25th August 2001, 01:34 PM	#4
Penguin diyAudio Member Join Date: Aug 2001 Location: Baltimore	Thanks Most informative dee ;-D

25th August 2001, 11:22 PM	#6
Penguin diyAudio Member Join Date: Aug 2001 Location: Baltimore	Even better thanks, Now i just have to figure out the loa on the PSU. Has anybody actually measured the Aleph 2 load on the PSU is it really 3.3 A per side? dee ;-D

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
Aleph2 pcb's, matched fets for aleph2 and aleph ono pcb's	MemphisJim	Swap Meet	1	23rd September 2005 07:15 PM
What's the difference between original aleph2 and DIY aleph2?	chris910	Pass Labs	3	17th August 2003 09:03 PM
Yet Another Aleph2!	kenny_(00)_	Pass Labs	21	6th July 2003 08:17 PM
Newbie Aleph2 PSU Questions	rcdaniel	Pass Labs	7	6th December 2002 09:20 PM
CL 60 for Aleph2	jeclk	Pass Labs	1	21st October 2002 10:10 PM


	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 August 2001, 02:17 AM	#1
Penguin diyAudio Member Join Date: Aug 2001 Location: Baltimore	Hi, What is the voltage drop on the PSU when it is loaded with the rest of the circutry. To get the rails to 45 VDC unloaded you need to use a 33V [(Vrms+1.4)*sqrt2] transformer. But is it enough? I am thinking about getting a pair of 500VA torroids from Piltron and they do have 33V secondaries. Would increasing the PSU capacitance decrease the voltage drop? dee ;-D

24th August 2001, 03:16 AM	#2
GRollins diyAudio Member Join Date: Feb 2001 Location: Columbia, SC	Dee, I'd recommend going for 750 VA, minimum (I've got 1000VA Plitrons on my Aleph 2s, filched from an unfinished project--still need to order proper transformers for the Alephs). 500 VA would be cutting it a bit thin. The 45V rail isn't unloaded--it's going to have to deliver 3A or so at that voltage, and that's at idle. If you pull back too much, the rail will drop, and the transformer will tend to run hot. Grey

25th August 2001, 06:46 PM	#5
tortello diyAudio Member Join Date: Jul 2001 Location: Genoa (ITALY)	Hi, you can find a good PSU software from Duncan's: http://www.duncanamps.com/ It works fine, I think.

27th August 2001, 12:08 AM	#7
GRollins diyAudio Member Join Date: Feb 2001 Location: Columbia, SC	More like 3A per side. I run mine a little hotter, simply because I can get away with it. The water-cooled system I use can dissipate the extra heat easily. Grey

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