post your leach amp photos

Wagener · 8th May 2004, 10:09 PM

I would like to see the leach amps built by the people of diyaudio.

Please post it here.

I have already found a few with the search but I want more.

Tony · 9th May 2004, 01:34 AM

here's mine:http://gallery44059.fotopic.net/p2774837.html

http://gallery44059.fotopic.net/p2774836.html

http://gallery44059.fotopic.net/p2774837.html

http://gallery44059.fotopic.net/p2774840.html
http://gallery44059.fotopic.net/p2774838.html

http://gallery44059.fotopic.net/p2774841.html
http://gallery44059.fotopic.net/p2774839.html

JensRasmussen · 10th May 2004, 02:11 PM

Here is my slightly modded Leach, The layouts are homemade.

\Jens

JensRasmussen · 10th May 2004, 02:18 PM

Close up of the small signal boards

JonMarsh · 10th May 2004, 03:43 PM

Nice work, Jens! Did you fabricate/etch your actual PCB's, too?

Is your running with high bias, considering the heatsink size?

Regards,

Jon

JensRasmussen · 10th May 2004, 04:27 PM

Hi Jon,

Yes I etched the PCBs myself using the equipment available at the school I studied at when I build the amp.

I was running the amp at about 100W idle for each of the four channels; however I could not perceive any difference when changing this to about 30W so this is the current (no pun intended) it’s now set at.

I made some modifications by adding three extra sets of output transistors, and changing the input small signal transistors to BC546/556 because these are commonly available here in Denmark.

The rest of the transistors are:

MJE340/350 for VAS and predrive stage.
MJE15032/15033 for driver stage.
MJL3281/1302 for output.

I noticed a lot of questions from Wagener regarding this amp I hope you don’t mind me answering here where more people can read it and hopefully use it.

The caps I used are almost all PP (Polypropylene) or PE (Polyethylene) types, except for the supply decoupling caps witch all are some form of electrolytic that I had I in stock.

The only ceramic caps I used are the ones used in the VAS stage for stability and the one in the feedback compensation network.

I used a large NON polarised electrolytic (470 µF) caps for input DC block, and another for the feedback cap that sets the low cut off frequency.

I hope this helps.

\Jens

Borc · 10th May 2004, 05:30 PM

Leach with 2SA1302,2SC5200 without current limiter, 10 Ohm output base resistors.

Borc · 10th May 2004, 05:32 PM

Another one

wigginjs · 11th May 2004, 05:32 AM

Is that a seperate power supply for each amp? Any particular reason?

Borc · 11th May 2004, 03:40 PM

No particular reason. Separation of both channels.
Transformers are quite cheap here ($35 for one).

8th May 2004, 10:09 PM	#1
Wagener diyAudio Member Join Date: Mar 2004 Location: Paarl	post your leach amp photos I would like to see the leach amps built by the people of diyaudio. Please post it here. I have already found a few with the search but I want more.

9th May 2004, 01:34 AM	#2
Tony diyAudio Member Join Date: May 2003 Location: Palatiw, Pasig City	here's mine:http://gallery44059.fotopic.net/p2774837.html http://gallery44059.fotopic.net/p2774836.html http://gallery44059.fotopic.net/p2774837.html http://gallery44059.fotopic.net/p2774840.html http://gallery44059.fotopic.net/p2774838.html http://gallery44059.fotopic.net/p2774841.html http://gallery44059.fotopic.net/p2774839.html __________________ http://www.electronicslab.ph/forum/i...?topic=32688.0

11th May 2004, 05:32 AM	#9
wigginjs diyAudio Member Join Date: Dec 2003 Location: Columbia, SC	Is that a seperate power supply for each amp? Any particular reason? __________________ The Four Chairs DIY Home Theater

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
High Current Leach/leach super amp	bowdown	Solid State	41	2nd March 2011 02:15 PM
Not being able to post replies on any post on Parts & Supplies	Mayank	Forum Problems	0	8th June 2007 02:38 PM
Not able to post photos	John Medvich	Forum Problems	11	28th November 2006 06:11 PM
Leach SuperAmp Photos	BeanZ	Solid State	40	29th August 2006 08:47 AM
More CES Photos	roddyama	Everything Else	24	21st January 2003 04:09 AM


	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

10th May 2004, 03:43 PM	#5
JonMarsh diyAudio Member Join Date: Jan 2002 Location: Livermore, CA	Nice work, Jens! Did you fabricate/etch your actual PCB's, too? Is your running with high bias, considering the heatsink size? Regards, Jon

10th May 2004, 04:27 PM	#6
JensRasmussen diyAudio Member Join Date: Jul 2002 Location: Denmark - Jutland	Hi Jon, Yes I etched the PCBs myself using the equipment available at the school I studied at when I build the amp. I was running the amp at about 100W idle for each of the four channels; however I could not perceive any difference when changing this to about 30W so this is the current (no pun intended) it’s now set at. I made some modifications by adding three extra sets of output transistors, and changing the input small signal transistors to BC546/556 because these are commonly available here in Denmark. The rest of the transistors are: MJE340/350 for VAS and predrive stage. MJE15032/15033 for driver stage. MJL3281/1302 for output. I noticed a lot of questions from Wagener regarding this amp I hope you don’t mind me answering here where more people can read it and hopefully use it. The caps I used are almost all PP (Polypropylene) or PE (Polyethylene) types, except for the supply decoupling caps witch all are some form of electrolytic that I had I in stock. The only ceramic caps I used are the ones used in the VAS stage for stability and the one in the feedback compensation network. I used a large NON polarised electrolytic (470 µF) caps for input DC block, and another for the feedback cap that sets the low cut off frequency. I hope this helps. \Jens

11th May 2004, 03:40 PM	#10
Borc diyAudio Member Join Date: Nov 2002 Location: Slovenia	No particular reason. Separation of both channels. Transformers are quite cheap here ($35 for one).

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

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