I just designed an amplifier to power big speakers with small voltage!

[jmillerdoc]

Originally Posted by bear

Your imagination seems to precede the thinking process by a bit. Nothing wrong with imagination, but electronic circuits have two key aspects:
_-_-bear

Yeah, I am constantly bummed about how my imagination is limited by reality...

[AndrewT]

Originally Posted by realflow100

hmmm what I'm meaning to say is I don't want to design an amplifier... I just want to build one that works.. is that too hard of a task to ask for?
I've made an amplifier that works.. and it works good.. but could be just a tad bit better..
if I can fit that tad bit better into my amplifier then I would be all set and I wouldn't ask anymore questions.. I'd be a happy camper with my amplifier and I'd be listening to music whenever I want and I wouldn't have to worry about the DC flowing to my speaker anymore..
but the bit of DC is messing everything up so badly..
I think I've finally figured out what he meant when he showed the schematic of the resistor and capacitor together... I think that's it..

typical of modern youth that not only want to be spoon fed, they expect it as the norm.

I will not assist in spoon feeding any Member.

[Ian Finch]

Originally Posted by realflow100

hmmm what I'm meaning to say is I don't want to design an amplifier... I just want to build one that works.. is that too hard of a task to ask for?

'Seems a reasonable expectation but you'll have to learn how to do that on your own steam. The level of education in electronics needed is not rocket science - It's junior High School standard but there are many educational forums and websites on basic electronics that cover audio amplifiers and that is obviously what you need, if only to copy the circuit diagrams, learn the symbols and how components work together to best produce a result. Its free, you have access to a PC so why not get on with it?

Google anything that comes into your head like "Basic Electronics" I came up with 12 sites offering on-line fun projects and advanced learning on the first page. There are hundreds. - It's all out there at a more helpful level than DIYAudio can offer you on a 1:1 basis, particularly if you want it in lego-blocks format rather than conventional electronic symbology and schematics.

Learn first, improve stuff along the way. If you then want to discuss ...SERIOUSLY...not as Lego block stuff, then we can help, as you will read in the help type threads here.

[sofaspud]

Here's a spoonful. Hopefully it won't go down like castor oil.
Acknowledgement to Lenk's Audio Handbook, 1st ed. by John D. Lenk
realflow100, I believe I speak for many when I say you should read this and demonstrate some understanding of the principles. You can apply this info to your transistor. We're simply asking for your input in return for our input.

[AndrewT]

I think I should download this example.
Must check that my understanding is up to speed.
But will Real do the same?

[bear]

realflow100, the circuit put up by sofaspud is the basic circuit that you want in as much as it is a single transistor, and gets rid of the DC. All you have to do is to make a power supply, pick the right power transistor and use approximately the right value resistors.

The neat part is that it will work.

Add just three more transistors and you can make a simple amp that will have more power and be what is called "push-pull". Do that after you get the first one made. Well, you have the first one made, so this would be the second, a push-pull your third.

Fyi, there are numerous other more simple descriptions and example of this circuit around, many online. So, just look at them, and you will start to see a trend and start to see how it works. Maybe even see a pictorial example or two.

As far as construction methods, look up "manhattan " style, and "dead bug" style, there are some others that will show up too.These are quick and dirty but effective ways to build circuits almost free, or free.

Whaddya say?

_-_-bear

[realflow100]

okay I put the resistor and the capacitor at the output and put my speaker to the capacitor and to the output and now the music quality is great and there's no more DC current flowing to my speaker!!
it works great!! thanks!
I'm very happy now!
the output has just a tad bit less bass but still way plenty loud enough
there's zero DC current flowing to my speaker when I wire my speaker up!
it pops out and then goes back in when I plug in the power supply
but the speaker doesn't stay popped out.. it goes back to it's resting place!! I'm sooo happy now!!
It works so great! and sound's amazing too!! probably one of the better sounding amplifiers I've ever heard!
I have AC coupled my amplifier and it seriously sounds great! and there is no more DC flowing to the speaker!! i'm so happy about that!
now I can play my music as long as I want without risking the life of my speaker!! woohoo!!
but my transistor gets a tad bit warmer than before (probably because I need to use a different resistor or one that's closer to the right value since I'm merely guessing by choosing one that just sounds good enough... but I need one that's actually closer to the correct value that I need to make my amplifier sound the best.
I have two capacitors each 1000uF's in parallel so I get 2000uF's for the output to my speaker.. I wanted to use two 4000uF capacitors but couldn't find any.
and it was so simple once I figured it out.. I don't know why I went through so much trouble to do something so simple..
and yeah I'll check out those attachments.
so far I only have
two capacitors.
two resistors.
one transistor
and my speaker.. that's really simple!!!!!!
I'm also using only a 5 volt power supply right now..

[sreten]

Originally Posted by realflow100

hmmm what I'm meaning to say is I don't want to design an amplifier... I just want to build one that works.. is that too hard of a task to ask for?
I've made an amplifier that works.. and it works good.. but could be just a tad bit better..
if I can fit that tad bit better into my amplifier then I would be all set and I wouldn't ask anymore questions.. I'd be a happy camper with my amplifier and I'd be listening to music whenever I want and I wouldn't have to worry about the DC flowing to my speaker anymore..
but the bit of DC is messing everything up so badly..
I think I've finally figured out what he meant when he showed the schematic of the resistor and capacitor together... I think that's it..

Hi,

Your stubbornness in refusing to accept reality is disappointing.

Your amplifier does not "work good" and cannot be made "a tad better"
to work properly. You have been provided with the tools and means
to work this out for yourself, seems that your not interested.

For battery power up to 12V look at the guts of discarded car casette/radios.
About 4W into 4 ohm for a single chip and about 16W for bridged chips.
The car stereo will have the necessary heatsinking and all the bits.

e.g. :

http://www.classiccmp.org/rtellason/chipdata/ha1377.pdf





Bridged HA1377, 17W into 4 ohms

Stay the hell away from any mains powered equipment.

rgds, sreten.

[jmillerdoc]

"Stay the hell away from any mains powered equipment."
Real, did you catch that? Given what I continue to see in your responses, I think this is the best and most important advice you have received.....

In case you don't understand....if it plugs into the wall, don't mess with it....

[Cal Weldon]

Direct mains powered equipment discussion is not allowed here. If this route is being considered, the thread will be closed and your posting privileges revoked.

It's that serious.