Have transformer, will build - diyAudio
Go Back   Home > Forums > Amplifiers > Solid State

Solid State Talk all about solid state amplification.

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
Reply
 
Thread Tools Search this Thread
Old 17th December 2004, 08:55 PM   #1
diyAudio Member
 
still4given's Avatar
 
Join Date: Oct 2004
Location: Victorville, CA
Default Have transformer, will build

I am the proud owner of this transformer.

I bought it by mistake for my ESP Project 101. It is too large for that project and now I am left wondering if there is a DIY project that can make use of this trannie. If you know of one, please let me know. Perhaps it will be my next project.

Thanks, Terry
__________________
X-BoSoZ, B1 Mezmerize, P101, Symasym, KSA 50, Aleph-X, Leach Low TIM, Leach Superamp, Dx MKIII, Super A, Honey Badger, JLH 1969, Gainclone. FetZilla, Peeceebee, VSSA PMI & jkuetemann, SKA GB150, Ovation nx & sx, AX&SX-14, TMG8, Slewmanster w/CFA-XH, Wolverine, Spooky, Symasui, Low TIM hybrid
  Reply With Quote
Old 17th December 2004, 11:45 PM   #2
moamps is offline moamps  Croatia
diyAudio Member
 
Join Date: Oct 2002
Location: Croatia
PASS AX
  Reply With Quote
Old 18th December 2004, 06:38 PM   #3
diyAudio Member
 
still4given's Avatar
 
Join Date: Oct 2004
Location: Victorville, CA
Do you mean the Aleph X?

I looked into that thread but it seemed that it is still under development. Are there PCBs availible for that design?

I've heard realy good things about the Aleph amps. I wouldn't mind tackling that next if it's not too complicated.

Thanks Terry
__________________
X-BoSoZ, B1 Mezmerize, P101, Symasym, KSA 50, Aleph-X, Leach Low TIM, Leach Superamp, Dx MKIII, Super A, Honey Badger, JLH 1969, Gainclone. FetZilla, Peeceebee, VSSA PMI & jkuetemann, SKA GB150, Ovation nx & sx, AX&SX-14, TMG8, Slewmanster w/CFA-XH, Wolverine, Spooky, Symasui, Low TIM hybrid
  Reply With Quote
Old 18th December 2004, 07:57 PM   #4
moamps is offline moamps  Croatia
diyAudio Member
 
Join Date: Oct 2002
Location: Croatia
Hi,

with this transformer (1000VA/2X56V) you can build a high power amplifier in Class AB (ca. 2X250W/8ohm). Normally, I would not see much point in building such a high-power amp for home use.

However, if you set primary winding to 230V, you'll get half the secondary voltage, which turns this transformer into a pretty good choice for, say, a Pass amp in Class A. Depending on power supply implementation (voltage losses), you could build A2, A5 or a high-power version of AlephX.

Before you decide to build a Class A amp, you should test the transformer for the intended purpose.

Detailed information and an overview of all the complexities involved in building such an amplifier can be found at www.passdiy.com (check out the gallery section).

I believe there are some PCBs circulating on the forum. Ask around. (I wouldn't know).

Regards,
Milan
  Reply With Quote
Old 18th December 2004, 10:14 PM   #5
paulb is offline paulb  Canada
diyAudio Member
 
Join Date: Jun 2001
Location: Calgary
Default Aleph-X group buy (in Wiki)

http://www.diyaudio.com/wiki/index.php?page=AX
  Reply With Quote
Old 18th December 2004, 11:18 PM   #6
diyAudio Member
 
Greg Erskine's Avatar
 
Join Date: Jan 2002
Location: Sydney/Australia
Hi still4given,

I think most of us use bridge rectifiers so the DC output voltage is greater the the AC secondary voltage, but if you use a full-wave rectification using just two diodes the DC output voltage is actually less than the AC seondary voltage. I can't remember the formula but I think it was .6 or .7 of the secondary. I have read some prefer full-wave over bridge rectification. So I think you could use this transformer for your original project and power a gainclone off the 17v secondaries.
__________________
Greg Erskine
  Reply With Quote
Old 19th December 2004, 01:09 AM   #7
joensd is offline joensd  Germany
diyAudio Member
 
Join Date: Dec 2001
Location: Germany
I´d go with moamps suggestions to wire the primaries in series leaving you with 28VAC which gives~40VDC+.
With that rail voltage you can simply build anything as it is quite a "standard" voltage. That includes P101 as well.
That said the transformer will be oversized for the purpose (unless you go class A) but it will also give great "regulation".
__________________
jens
  Reply With Quote
Old 19th December 2004, 05:47 PM   #8
diyAudio Member
 
still4given's Avatar
 
Join Date: Oct 2004
Location: Victorville, CA
Quote:
Originally posted by moamps
Hi,

with this transformer (1000VA/2X56V) you can build a high power amplifier in Class AB (ca. 2X250W/8ohm). Normally, I would not see much point in building such a high-power amp for home use.

However, if you set primary winding to 230V, you'll get half the secondary voltage, which turns this transformer into a pretty good choice for, say, a Pass amp in Class A. Depending on power supply implementation (voltage losses), you could build A2, A5 or a high-power version of AlephX.

Before you decide to build a Class A amp, you should test the transformer for the intended purpose.

Detailed information and an overview of all the complexities involved in building such an amplifier can be found at www.passdiy.com (check out the gallery section).

I believe there are some PCBs circulating on the forum. Ask around. (I wouldn't know).

Regards,
Milan

Hi moamps,

I am not very experienced with DIY amps but of the amps I own, Hafler DH200, Hafler P230, Soundcraftsmen PCR800 & Soundcraftsmen S860, the S860 is the best sounding and the most powerful. It's supposed to be 240wpc @ 8ohms.

I mainly use these in my studio for reference. Sometimes they are played fairly loudly. I drive JBL 4425's, 4412" and Yamaha NS1000's.

Anyway, perhaps the amps I have are not as efficient as the Aleph amps. They are in excess of 100wpc.

May I assume that if I run this trannie at lower voltage that I would have greater VA?

I'm not sure I'm experienced enough yet to tackle the Aleph X. Seems like most folks are tweaking them as they go. I would be better off with a design that is proven I think. I know that I don't have enough understanding to start tweaking someone's design.

Blessings, Terry
__________________
X-BoSoZ, B1 Mezmerize, P101, Symasym, KSA 50, Aleph-X, Leach Low TIM, Leach Superamp, Dx MKIII, Super A, Honey Badger, JLH 1969, Gainclone. FetZilla, Peeceebee, VSSA PMI & jkuetemann, SKA GB150, Ovation nx & sx, AX&SX-14, TMG8, Slewmanster w/CFA-XH, Wolverine, Spooky, Symasui, Low TIM hybrid
  Reply With Quote
Old 20th December 2004, 08:36 AM   #9
diyAudio Member
 
jacco vermeulen's Avatar
 
Join Date: Oct 2004
Location: At the sea front, Rotterdam or Curaçao
Send a message via Yahoo to jacco vermeulen
I am a bit surprised by the responses.

You may have noticed that transformers can get hot !
A 1000VA is designed for delivering that power for the rated voltage.
The core of the toroid has flux large enough to transform 1000VA.

Normal engineering means that primary and secondary windings are dimensioned in accordance with the voltage and power rating.
Meaning that the secondary windings are good for nearly 9 amps at 56 volts.
Derating the voltage by putting 110 volts on 230 volt primaries may lower the secondar output voltage, the secondary windings are still only good for 9 amps.

Reduce the input voltage by half, out comes half of the power, 500VA max !
And that does not make real sense, why buy a 1000VA transformer if you are going to use only half of that.

Transformer windings are isolated well enough for way beyond a thousand volts.
Putting 220 volts on 110 volt primaries is more realistic than the reverse strategy.
As the toroid is able to deliver 1000VA the output current is half of the design current for which the secondary cross sections are dimensioned.

56 Volts is good for at least 250 watts, place a small voltage transformer in series with the big one to feed the front stage of the amplifier and you are talking way beyond 300 watts.
Bridge the amps and you have a 500+ amp, strong enough to drive a serious subwoofer.
Overhere people have built 1000 watt amplifiers, plenty of designs available for those who feel the need.

If you decide to go for a smaller power amplifier, unwind the secondaries to whatever you need.
Put 110 on 220 primaries, extract a thousand watts and you might end up with an nice burning toroid by Christmas time !
__________________
The buck stops Here
  Reply With Quote
Old 20th December 2004, 08:36 AM   #10
AndrewT is offline AndrewT  Scotland
diyAudio Member
 
Join Date: Jul 2004
Location: Scottish Borders
Hi,
Run your tranny at half volts if you want.
You cannot exceed the VA rating except for short term overloads.
With 1000va to play with, it will cover all except a large classA.
Are you able to confirm the current rating of all the windings?
It will give you more flexibility if you can series the 15vac onto the the high voltage. But if they are only low current then separately rectify & then stack on top of main output as a driver regulator feed.
regards Andrew T.
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
WTB: pwer transformer for my aikido build wendell Swap Meet 0 12th February 2009 04:58 PM
Need advice - what can I build with this power transformer? zobsky Tubes / Valves 6 22nd March 2007 01:47 AM
How Build Toroidal Transformer samsagaz Parts 5 12th March 2007 05:33 PM
BYOT (Build Your Own Transformer) Bama Slamma Power Supplies 3 23rd December 2006 05:14 PM
help to build a transformer to car amp. Dj BASS AMP Solid State 17 16th May 2004 12:57 AM


New To Site? Need Help?

All times are GMT. The time now is 05:21 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright ©1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2