Quote from: Enzo on May 11, 2009, 09:45:54 PM
You can copyright your schematic though.  Redraw it and you are OK.

thax you!!!

Quote from: valdiorn on May 09, 2009, 02:12:57 PM
Circuit designs are actually not protected by copyright, unless you design something that is considered new technology and you patent it. Most of the circuitry in Marshalls is based on designs and technology that date back to before 1950, so it can not be patented because it's pretty much considered "common knowledge" for electrical engineers.

A circuit is just like a recipe for baking a cake. But have you ever had the same kind of cake, baked by two different individuals? they taste different because everyone uses their own methods of making it, even if the recipe is the same.

Also, building an amplifier is not something everyone can do, it takes time and skill, and sometimes a company like Marshall can just do a better job for less money than you ever could. (getting back to the cake analogy, why do we have bakeries if we can all bake our own cakes?? Well, because they make some fine cake, and maybe we just want a damn cake without the hassle of making it )

Thank you very much!
different engineers ,different workmanship.

Quote from: Jack.Straw on May 06, 2009, 02:52:47 PM
pattonBa, thanks for the schematic.  Have you tried it yet?

sorry,no. 

 I have the same problem with you.
i found a schematic of 2 line mixer.
http://www.freeinfosociety.com/electronics/schemview.php?id=1060

Quote from: Enzo on May 04, 2009, 10:19:59 PM
teemuk is certainly correct.

Not only that, but Marshall schematics are readily available.

what's the different between schematics and circuit diagram?

Hi all!
  Why we can get mashall's cuicuit diagrams?i think  the diagrams are the secrets of the company.
If we all have mashall's diagram and  we all can build AMPs like marshall.Who will buy  marshall?

:loco

Quote from: joecool85 on May 03, 2009, 08:02:24 PM

Quote from: Zappacat on May 03, 2009, 01:39:23 AM
I'd like to build a combo 2x12 stereo amp that has balanced stereo sends(to send to the PA).  It doesn't need much(if anything) on it for a tone stack.  The more power the better.  It just needs to be uncolored sound.  I guess what I'm looking to build is very similar to a stereo Tech 21 power engine.  Could any of you point me in the right direction.  I'd really appreciate it.

I'm seriously considering trying this amplifier http://sound.westhost.com/project27.htm 100W Guitar Amplifier Mk II.  Have any of you built this amp?  The only thing I see that it lacks is stereo.  Outside of that it seems to be well documented and I like the way he explained it.

The more power the better?  How about 240w RMS?  Build a stereo amp with two LM4780 chips in bridged mode (they're built for stereo use), easy to build, tons of power.  If that's too much power for you, a single LM4780 will yield half the power.  Plan on having a nice big heat sink whatever you do

yep!

ME too. i would like DIY.yesterday i built a preamp,it is work,but there lots of noise.
i don't know what happened.
good luck!