Why no SEWA or equivalent kits? - diyAudio
Go Back   Home > Forums > Amplifiers > Pass Labs

Pass Labs This forum is dedicated to Pass Labs discussion.

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 24th November 2006, 04:06 AM   #1
diyAudio Member
 
Join Date: Jan 2006
Location: Wisconsin....what did you expect?
Send a message via AIM to Spasticteapot
Default Why no SEWA or equivalent kits?

I'm a bit of an audio newbie, but I've always been curious - why no kits of the "SEWA" low-power class-A amplifier?

With a similarly simple class-A preamp, a whole amplifier could be made for under $100, assuming a suitably ginormous power transformer could be sourced from something broken.
  Reply With Quote
Old 24th November 2006, 05:38 PM   #2
diyAudio Member
 
gmilitano's Avatar
 
Join Date: Apr 2004
Location: Winnipeg, Manitoba
Teapot,

Take a look at Mark's Class A MOSFET Amplifier.

It looks fairly simple. To cut down on costs, don't use a choke in the PS and perhaps you can try car bulbs instead of the big power resistors.

Use a breadboard for the circuit and the parts should be able to buy at a local electronics shops.

For a big transformer, look around for a dead computer UPS.

Cheers.
  Reply With Quote
Old 24th November 2006, 05:46 PM   #3
diyAudio Member
 
Join Date: Jan 2006
Location: Wisconsin....what did you expect?
Send a message via AIM to Spasticteapot
Quote:
Originally posted by GG
Teapot,

Take a look at Mark's Class A MOSFET Amplifier.

It looks fairly simple. To cut down on costs, don't use a choke in the PS and perhaps you can try car bulbs instead of the big power resistors.

Use a breadboard for the circuit and the parts should be able to buy at a local electronics shops.

For a big transformer, look around for a dead computer UPS.

Cheers.

Getting the parts is no problem for me.
However, I'm surprised that, considering the low parts count, nobody has made a small PCB on which all the small components can be mounted.

Olimex will make something like 12 1"x2" double-sided boards for about 26$.

Yes, I'm aware that I could just build one myself, but ordering one or two of every part gets expensive - and my point-to-point skills are lacking.
  Reply With Quote
Old 26th November 2006, 03:23 PM   #4
diyAudio Member
 
gmilitano's Avatar
 
Join Date: Apr 2004
Location: Winnipeg, Manitoba
Quote:
Originally posted by Spasticteapot

Getting the parts is no problem for me.
However, I'm surprised that, considering the low parts count, nobody has made a small PCB on which all the small components can be mounted.

Olimex will make something like 12 1"x2" double-sided boards for about 26$.

Yes, I'm aware that I could just build one myself, but ordering one or two of every part gets expensive - and my point-to-point skills are lacking.

I don't imagine that there would be much demand for such a small PCB. If you use a protoboard you get much more felxibility in being able to fit locally available parts or parts you have on hand. Furthermore, a protoboard can be purchased locally and at a fraction of the price. You should be able to get a protoboard for the price of shipping a PCB.

You should not have to order any parts unless you want to use a very high quility MOSFET.

There is not much more skill required for doing a protoboard project versus a PCB.
  Reply With Quote
Old 26th November 2006, 03:39 PM   #5
diyAudio Member
 
Join Date: Jan 2006
Location: Wisconsin....what did you expect?
Send a message via AIM to Spasticteapot
Quote:
Originally posted by GG



I don't imagine that there would be much demand for such a small PCB. If you use a protoboard you get much more felxibility in being able to fit locally available parts or parts you have on hand. Furthermore, a protoboard can be purchased locally and at a fraction of the price. You should be able to get a protoboard for the price of shipping a PCB.

You should not have to order any parts unless you want to use a very high quility MOSFET.

There is not much more skill required for doing a protoboard project versus a PCB.
To be honest, newbies like myself are likely to muck up the choice of parts. If everything could be put in a nice little box (like the Gainclone kits), it would make it easier for newbies to build them.
  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
SEWA - Seven Watt Amplifier Mad_K Pass Labs 938 6th May 2014 06:33 PM


New To Site? Need Help?

All times are GMT. The time now is 08:26 AM.


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