Leach Superamp Diy

[acenovelty]

Make your own 270W Leach Superamp

[IMG][/IMG]

This slightly modified board lay out allows for using computer power connectors to simplify the wire connections to the heat sink mounted transistors. You may want to make an "output" board for mounting the TO3 transistors easier.
The "foil pattern" and parts placment for making your own circuit board is located on a server at my ICQ address posted here. If you have trouble getting the files, look to your own computer settings in ICQ. I cannot trouble shoot your configuration. Best time of the day to get the files is after 6PM Pacific Standard Time. This is a T1 line and the files should take about 3 minutes to download if you have a reasonably fast DSL type connection.
A zipped parts list is included with parts as described as on:
http://users.ece.gatech.edu/~mleach/lowtim/ and:
http://users.ece.gatech.edu/~mleach/superamp/
and includes some sources for trannies etc.

A careful and complete reading of these doc's is essential to building this amp so that it works first time. The most rank amateur can build this amp if the instructions are followed exactly. If you decide to modify the amp to suit your own desires by using components other than described in Prof. Leach's parts list, do so at your own peril.

There will be no "group" buy of anything required to build the amp sponsored by me. This is Do It Yourself, not done by some other tweedle-dee or tweedle-dumb. Board parts other than transistors are cheap. The most expensive transistors can be had as samples from:
http://onsemi.com/ and you should decide how to get them.
Prudent purchases of components will allow you to build this amp for about $300-$400, most of which will be in the transformer, caps, heat sinks and case. Press-n-Peel Blue Transfer Film by http://www.techniks.com/ works very well for making your board. You need a laser printer or copier and a large base clothing iron. Beware the WAF.
A good read about power supply design that may improve this amp is by Dejan V. Veselinovic titled Designing your own power supply located here: http://zero-distortion.com/start.htm

Some additional pics will be posted later showing a more complete board mounted on heatsinks and may give you ideas about how to make your own output boards.

You may freely distribute anything found here as most of it is easily found on the web. The images I have provided are yours to use or modify as you please and I take no liability for their use or accuracy.
Requests for modifications, complaints about layout or choice of parts will be ignored. I have built several configurations of this amp without help from anyone and so can you.

This amp is probably over kill for most folks living room applications, but you do get bragging rights to a 270 Watt amp. And most likely you'll discover your speakers really are not that great after all.

Prosit

[sek]

Hi acenovelty,

thank you for contributing your effort.

But, why did you

1. initiate two threads with the same topic,

2. didn't reply to a valid comment here?

Sebastian.

[acenovelty]

I did not make two posts. How that happened is beyond me.
Perhaps our moderator will take down the other one.
And allow me to rephrase ."Requests for modifications, complaints about layout or choice of parts will be ignored." to "ALL complaints will be ignored, including but not limited to the board layout, parts choice, requests for modifications, size of files, ICQ, personel vendettas, etc."


Anyone who wishes to build this amp with the layout may do so as they choose with any modification they see fit.... It's nothing to me if you do or do not. You are free to press on the back button on the browser and go away to some more interesting place.

EVERYTHING that you need to know about building the amp is in Prof. Leach's documentation.

The ICQ icon is not showing in the browser despite repeated attempts to activate it. The number is 310-361-573

Prosit

[acenovelty]

Output boards

ICQ # 310-361-573

[acenovelty]

From the end

ICQ # 310-361-573

[acenovelty]

Heatsink side

ICQ # 310-361-573

[still4given]

Hi Ace,

What a great idea! I wish I had used your layout instead of the one on Prof Leach's site. I would have liked to have the extra room and those connectors would have tidied things up a bit, I feel.


I'll be folowing this thread as it progresses.

Blessings, Terry

[JensRasmussen]

Hello acenovelty,

Arguing so eagerly in the super amp redesign thread against my new PCB layout deserves some sort of help from me to your work, that you have now presented.

First of all, we clearly don’t agree on the choice of output devises. Let’s leave it at that.

I can see some obvious problems like the lack of sufficient track width in high current nodes.
It looks like you tried to make a solution by adding solder to the tracks. This can make the tracks peel off - it might be better to add wider tracks.

The bias potentiometer could be better, I think that a multi turn type will last longer and be less prone to failure.

With all that extra board space, I would add some fuses and extra supply capacitors.

This is just my initial thoughts to help you improve your design.

\Jens

[Mikett]

I've experienced subpar connector reliability from these molex connectors. A step up to a higher grade would be better especially on output devices. The price is right, but many PCs have connector issues with these.

[acenovelty]

Anyone who wishes to build this amp with the layout may do so as they choose with any modification they see fit.... It's nothing to me if you do or do not. You are free to press on the back button on the browser and go away to some more interesting place.