Components of solid state amps

[marcipicus]

I want to make a ss amp using the english channel and uno as the clean and dirty channels respectively. How is a ss amp put together preamp power amp. if someone could tell me what components are involved and how to put them together i would greatly appreciate it.

[Hal]

preamp - capacitor - power amp - output transformer - speaker.


you should be able to find a couple hundred power amp schematics online, mostly aimed at hifi applications, but some of which should work as an amp.  You can even use something simple, like a 3886 power amp chip, but I'm not sure if you'll love those results...

its a cool idea :-D

[marcipicus]

Thanks for your help. As usual for me your post breeds more questions since i know basically nothing.
1. Is the capacitor special in any way or just an electrolytic or something?
2. How do i know if a power amp schematic would be useful for an amplifier and what is one that has already been used with good results?
3. How would i switch between preamps?
4. What would be a suitable speaker?
5. What are some good books that would bring me up to the required level of
knowledge for this project (from the basic beginner to fairly knowledgable) so that i can stop asking stupid questions on this forum
Thanks again if you can help especially with the books

[cd]

If you know absolutely nothing, start with Craig Anderton's books.  Specifically:

- DIY Projects for Guitarists (there's a practice amp project in there)
- Electronic Projects for Musicians (this is the one to start with if you know zip)

[lightningfingers]

Yeah i was wondering about htis too.....

how do you make a power amp from power transistors?

I wanna make me a little FET version of the SuperLead :twisted:

[Hal]

http://www.aaroncake.net/circuits/amp.htm  IC design
http://sound.westhost.com/project3a.htm    many transistor, 60-80w
http://www.pjrc.com/tech/cbw/    50w - easy to follow project


i found those in a couple seconds with google.

The coupling capacitor should already be built into the preamp, the the OT in the power amp schematic - I just wrote it to show how they get linked to eachother.

For switching, I think you can use a dpdt switch kinda like an a/b box would - grounding the output of the "preamp" you just switched from.

[Johan]

the main purpouse of the poweramp is to provide enough current to drive a low impedance load, like a speaker. what your amp will sound like is much more dependent on preamp design and speaker choice than the design of the poweramp ( as long as you dont intend to overdrive the poweramp, like you do in old tubeamps ), so NOT using one of the many powerships that are availeble is almost silly. You dont have to deal with stuff like x-over distortion and overcurrent protection. just go with the values given in the application notes of the ship you deside on, and you will have a great little amp with roughly the same amount of parts as a simple overdrive
I like these...up to 30watt LM1875, up to 65watt LM3886 up to 90watt TDA7293...

good luck

Johan

[cd]

Forget about using power transistors.  Just use a TDA2050 chip (look up the datasheet), all the big amp makers use chips like these for their small solid state amps.

[marcipicus]

would this schematic be suitable for this project? If so are there certain parts of it I should omit?

http://home.ca.inter.net/~cfraser/Gainclonehome.htm

Also what size should the speaker be for a  30-32 watt amp 10" or 12" and what are some speakers that are know for having good sound?


P.S. I've heard of celestion green backs and was wondering if they are any good.

[cd]

Forget about the Gainclone, it's simple but inefficient, which means  the power supply has to be necessarily large (light filtering, but lots of VA required).  

What is your goal for this project?  Are you looking for good sound, or are you trying to do this cheap?  If you're trying to save $$$, forget about scratch building - you'll end up spending more than just buying used.  Find a used SS amp, build the ROG preamps in a separate box and plug into the FX return (or make your own power amp in).

[marcipicus]

With this project i want to make a good sounding solid state practice amp that isn't to hard to carry around.

What power amp design would you suggest?

Thanks again

[Fret Wire]

http://www.redcircuits.com/Page52.htm

[spongebob]

With this project i want to make a good sounding solid state practice amp that isn't to hard to carry around.

Have you tried one of the LM386 amps yet? If not, I would suggest you build one of these first, even with their 1 Watt rating they can get pretty loud! If you search the forum you will find some nice pictures these amps!

http://www.national.com/ds.cgi/LM/LM386.pdf
http://www.runoffgroove.com/ruby.html

And putting the FET sims infront of it should be no problem either.

[cd]

With this project i want to make a good sounding solid state practice amp that isn't to hard to carry around.

What power amp design would you suggest?

Thanks again

Use that TDA chip I mentioned earlier.  You can get up to 30 watts out of it, Fender used to use it for everything from 10-25 watts.

However if you're looking for a small amp, you might as well go buy a used one.  I've seen people selling small SS amps for less than $100.  There's no way you can build anything better for less than that.