I have +-50volt rails @ 1000VA, 37600uF per rail: what would you reccomend?

SkinnyBoy · 9th October 2004, 05:20 AM

as the title says.... looking for a schematic, mosfet or transistor (probably transistor, as the rails are kinda low) looking to make full use of the transformers.... maybe 4 channels?? THANX!

hehe, yes, I'm back

Luke · 9th October 2004, 05:24 AM

a leech amp maybe?

SkinnyBoy · 9th October 2004, 05:33 AM

I probably should have mentioned I'm kinda limited for space..... also, I'm thinking about making it +-63 volt rails (adding an extra torodial) as I know 50 is really too low.....

what about one of the 400watt aussie amps off +-63 volt rails, rather than 70??

SkinnyBoy · 9th October 2004, 06:20 AM

I'm begining to think this project isn't even worth it.... although I did just order more transformers, and today went and bought a (hopefully) suitable case for it....

I've spent $155 so far... that includes a rack mount case, 1250VA of toroidals, and 75,200uF of caps.... but the toroidals are so big that I'm not really left with enough room for the heatsinking... I don't want to have a seperate PSU to the power amp either.

finding suitable heatsinks will be a pita.... and output devices for the amp will set me back another $150 or so.... so far, everything has been cheap.... maybe someone has some surplus mosfets or transistors I could buy??? LATER!!!!

AndrewT · 9th October 2004, 09:35 AM

Hi,
your 50v rails do not seem too low.
I ran 625va toroid 4% regulation 35vac into 2 Crimson 1704 boards. I got 110w into 8r both channels driven and 200w into 4r one channel driven. and the output stage only has one pair of 2n3773. Crimson has put in good protection that you never hear & I have never damaged them in 20 years & over 3 generations of boards.
Caps started as 2x4,700uF per rail per board.
Later amps run 3x 6,800uF per rail per board, bass strength and depth much improved. Bypass was mix of polycarbonate & polystyrene. input cap changed to 2x33uf solid tant back to back bypassed with 1uf polysomething, I,m getting too old in the grey matter.
regards Andrew T.

joensd · 9th October 2004, 09:55 AM

The Crescendo ME would fit nicely.
I built it myself and it´s a nice amplifier.
If you need the layout drop me a mail.
I believe the schematics are here in the forums.

SkinnyBoy · 9th October 2004, 01:23 PM

Quote:

Originally posted by AndrewT
Hi,
your 50v rails do not seem too low.
I ran 625va toroid 4% regulation 35vac into 2 Crimson 1704 boards. I got 110w into 8r both channels driven and 200w into 4r one channel driven.

see, I feel that having 1000va of transformers for 220watts of output is a TAD over rated

Kilentra · 9th October 2004, 03:44 PM

How about a bridged circuit?

alvaius · 9th October 2004, 07:29 PM

Welding! ... sorry, could not resist.

SkinnyBoy · 10th October 2004, 06:04 AM

Quote:

Originally posted by Kilentra
How about a bridged circuit?

I have considered that, but would really like the ability to be able to bridge the whole amp into a single channel (if I ever need to in the future)

Quote:

Originally posted by alvaius
Welding! ... sorry, could not resist.

huh? what do you mean?

make a welder??? I already have one... lol

9th October 2004, 05:20 AM	#1
SkinnyBoy Banned Join Date: Nov 2002 Location: Adelaide, Australia	I have +-50volt rails @ 1000VA, 37600uF per rail: what would you reccomend? as the title says.... looking for a schematic, mosfet or transistor (probably transistor, as the rails are kinda low) looking to make full use of the transformers.... maybe 4 channels?? THANX! hehe, yes, I'm back

9th October 2004, 09:55 AM	#6
joensd diyAudio Member Join Date: Dec 2001 Location: Germany	The Crescendo ME would fit nicely. I built it myself and it´s a nice amplifier. If you need the layout drop me a mail. I believe the schematics are here in the forums. __________________ jens

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
Filter Cap Directly from Rail to Rail, excluding Center Tap	Workhorse	Power Supplies	8	29th August 2007 12:33 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


	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

9th October 2004, 05:24 AM	#2
Luke diyAudio Member Join Date: Sep 2001 Location: Wellington NZ	a leech amp maybe?

9th October 2004, 05:33 AM	#3
SkinnyBoy Banned Join Date: Nov 2002 Location: Adelaide, Australia	I probably should have mentioned I'm kinda limited for space..... also, I'm thinking about making it +-63 volt rails (adding an extra torodial) as I know 50 is really too low..... what about one of the 400watt aussie amps off +-63 volt rails, rather than 70??

9th October 2004, 06:20 AM	#4
SkinnyBoy Banned Join Date: Nov 2002 Location: Adelaide, Australia	I'm begining to think this project isn't even worth it.... although I did just order more transformers, and today went and bought a (hopefully) suitable case for it.... I've spent $155 so far... that includes a rack mount case, 1250VA of toroidals, and 75,200uF of caps.... but the toroidals are so big that I'm not really left with enough room for the heatsinking... I don't want to have a seperate PSU to the power amp either. finding suitable heatsinks will be a pita.... and output devices for the amp will set me back another $150 or so.... so far, everything has been cheap.... maybe someone has some surplus mosfets or transistors I could buy??? LATER!!!!

9th October 2004, 09:35 AM	#5
AndrewT diyAudio Member Join Date: Jul 2004 Location: Scottish Borders	Hi, your 50v rails do not seem too low. I ran 625va toroid 4% regulation 35vac into 2 Crimson 1704 boards. I got 110w into 8r both channels driven and 200w into 4r one channel driven. and the output stage only has one pair of 2n3773. Crimson has put in good protection that you never hear & I have never damaged them in 20 years & over 3 generations of boards. Caps started as 2x4,700uF per rail per board. Later amps run 3x 6,800uF per rail per board, bass strength and depth much improved. Bypass was mix of polycarbonate & polystyrene. input cap changed to 2x33uf solid tant back to back bypassed with 1uf polysomething, I,m getting too old in the grey matter. regards Andrew T.

9th October 2004, 03:44 PM	#8
Kilentra diyAudio Member Join Date: May 2002 Location: Cambridge, MA, USA	How about a bridged circuit?

9th October 2004, 07:29 PM	#9
alvaius diyAudio Member Join Date: Feb 2002 Location: Toronto	Welding! ... sorry, could not resist.

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