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Solid State Talk all about solid state amplification.

I just designed an amplifier to power big speakers with small voltage!
I just designed an amplifier to power big speakers with small voltage!
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Old 16th October 2012, 12:12 PM   #61
jkuetemann is offline jkuetemann  Canada
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My I suggest you become familiar with what a schematic diagram is and how to read one. There are numerous resources out there, many on the internet so just google away. Personally I feel there is no substitute for a good book on the subject. Pay a visit to a library.

Have a read through this and look for other similar information.

Beginners' Guide to Electronics, Part 1 - Basic Components Explained

If you want things to develop you will need to learn how to basically speak the language of electronics.
---Jason Kuetemann---
Power is only granted to those willing to lower themselves enough to pick it up.
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Old 16th October 2012, 12:15 PM   #62
sofaspud is offline sofaspud  United States
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I'm not hating on you. Did I make my post purposely uncomfortable? I tried. I want to instill some motivation and confidence in you. You are stuck on "transformer" and that isn't the answer you seek.
Transformers do not create power. When you see them used as you're proposing they are being used for impedance matching; a high impedance at the collector is transformed to a low impedance to match the speaker impedance.
My advice to improve your circuit and increase the power output is to properly bias the transistor and increase the power supply voltage. This will require a few more resistors and a couple of capacitors. If you don't have any more parts, then you've reached the end of the road with your circuit, as has been pointed out several times. With more parts, you can get help here with connecting them all together correctly.
Your present circuit only has 5 components; you should understand what the function of each is. If you don't, that is probably the question to ask.
It is error only, and not truth, that shrinks from enquiry. - Thomas Paine
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Old 16th October 2012, 04:18 PM   #63
jmillerdoc is offline jmillerdoc  United States
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You gotta start somewhere and I think you are doing just fine....don't confuse the sometimes sharp criticisms you get here on the forum with hate...Ihave seen very little hate around these parts. Frankly, for 15 I am impressed....continue down this hobby path and someday you will be building cool stuff from scratch and spending gobs of money too...it is a double edged sword...fun hobby but can become an obsession quickly.

If you want to do something really cool and have a little bit of cash I suggest you pick up one of Brian GT's chipamp kits at chipamp.com...they are superb and easy to construct. You will learn a lot on the way and have something you can continue to tweak and make better....probably the best bang for you buck available in amplifiers you can DIY. If you are interested email me, I have a few toroid trannys laying around that, if you will commit to building one of these chipamps, I will literally give you...and I will give you some pointers along the way and help you build it. I even have some cheap binding posts and RCA jacksi will throw in...all you need to buy is the kit and make a suitable chassis and you will have an awesome little 60wpc HiFi amp that is difficult to beat by any standard. So, if you are willing to take this to the next level shoot me an email and I will set you up....


All you need is the stereo kit with one power supply and the two amp boards....I think they are $90...there is also another website similar to BrianGT's that sells a kit based on the LM3875 instead of the LM3886....I can't remember the site but someone here will undoubtably know what I am talking about and can chime in.

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Old 16th October 2012, 06:17 PM   #64
sreten is offline sreten  United Kingdom
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Location: Brighton UK
Originally Posted by realflow100 View Post
also I'm only 15 years old and i'm home schooled at K12 | Online Public School, Online High School, Online Private School, Homeschooling, and Online Courses options and I don't know hardly anything about electronics except how to wire something together to make it work... I don't know how to read a wiring diagram unless it shows exactly where every wire goes to the correct end of the correct component and which end of each component goes to the correct end of the other component..
I have no clue how to read a diagram if it doesn't state exactly which positive or negative or where which positive or negative wire goes where.
it's not like I can just look at it and guess which wire goes where.. I wouldn't even know where to hook the output positive and negatives to. or even where they are in the diagram..
I would need an image taken from a camera with labels showing which end of each wire is positive or negative and where it goes to which other end of the other component
then I could just make it look the same already knowing which end of my components are positive or negative and connect it the same way as the picture.

So basically you know nothing, think your amplifier works perfectly,
(which it doesn't), and want to be led by the nose to something
else without having a clue what is going on, you just want to
build stuff from an "idiot proof" guide. It doesn't work like that,
except for building something like a battery powered guitar effects
pedal or headphone amplifier, following a step by step pictorial guide.
You won't learn much though, just being an assembler.

Its tough starting, why not analyse your amplifier in Tina ?

If you can't get past what is in post #41, stick to building well
documented kits and give up any idea you can design anything.

rgds, sreten.

Last edited by sreten; 16th October 2012 at 06:22 PM.
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Old 16th October 2012, 07:41 PM   #65
magnoman is offline magnoman  United States
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Is the input short to the postive supply intentional on post #41 ?

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Old 16th October 2012, 08:11 PM   #66
cliffforrest is online now cliffforrest  United Kingdom
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A comment was deleted ....

If the supply was a true zero impedance at AC (as it "should" be) then yes, the input signal is shorted.

The DC connection is needed to bias the transistor ON. It "works" because of supply impedance.

This contradiction shows just how crock this circuit is!
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Old 16th October 2012, 08:22 PM   #67
sreten is offline sreten  United Kingdom
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Your both right there is a mistake in post #41 transcribing post #40.

rgds, sreten.

Last edited by sreten; 16th October 2012 at 08:39 PM.
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Old 16th October 2012, 10:41 PM   #68
realflow100 is offline realflow100  United States
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lol I have no money I don't have a job so there's no way i'll ever be spending anywhere close to that much money on anything
plus I don't have a credit card either so i couldn't buy it even if i wanted to.
I don't get any kind of income either so i'm pennyless I get all my stuff from the dumpsters that are nearby I haven't bought a single penny worth of stuff for my amplifier that i'm making..
except for the subwoofer which my mom bought for me a long time ago when we had enough money but now my mom barely gets 600 dollars a month so there's no way we can buy stuff like that.
we can barely live as it is.
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Old 17th October 2012, 01:37 AM   #69
bear is offline bear
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I just designed an amplifier to power big speakers with small voltage!
Ok, here's how to get a boatload of parts.

The first thing is to grab all of the old CRT TVs and computer monitors. Open them up, cut out the boards, keep them. They are chock full of very good useful parts. Each thrown out board has at least $100 worth of parts, if you had to order them new. Maybe double that. Not all will be useful, but a whole lot are.

(don't pass up the radios and anything else electronic)

Next download that deja vu reader and the book that was suggested. It is possibly the *best book* ever written to learn something about electronics. Why? Because it is written so that you can read it and skip the math (if you want to). Great book.

Now I do not know where you live, but you can find a local ham radio club online, and maybe email them or go to a meeting and let them know that you are interested in learning about electronics - not everyone will want to help, but chances are you can find people there who will help with ideas, parts and even give you a ride to meetings, etc... some of these folks have rooms full of parts. I do. If you were around here, I'd give you some, no problem.

If you read up a bit, and you can fix some things like guitars and guitar amps, I'd bet you can make enough bucks to feed your hobby. Not to mention doing hi-fi amps and speakers for people in your school.

You might let us know where in the country you are, because someone on DiyAudio just might be next door!

It's cool that you want to build something... you can do it.

I blew up all sorts of stuff when I started out. No clue what I was doing. But it is a GOOD IDEA to follow a simple circuit that is known to work when you start. Again, you can get the necessary parts for such a thing from the places I just said.

You can get help figuring out what parts are the right ones by reading online and asking good questions here.

So your next steps are:

- build up a pile of boards for parts
- identify a few possible simple circuits to build - preferably one with photos illustrating (if you can find that)
- read The Art of Electronics and any other tutorials you can find
- ask here before you go ahead and build the next project for some help and ideas

You will get past the initial difficulties quickly, if you do something like this.

http://www.bearlabs.com -- Btw, I don't actually know anything, FYI -- every once in a while I say something that makes sense... ]
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Old 17th October 2012, 05:12 AM   #70
realflow100 is offline realflow100  United States
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okay and i live in SC near orangeburg if anyone knows where that is
there's a radio shack nearby with loads and loads and loads of electronic stuff like transistors diodes resistors and many many variable capacitors and different capacitors and probably new stuff that I haven't seen yet because I haven't been there for a long time.. and I've even seen a amplifier kit that they had.
I also want to try a breadboard instead of soldering..
plus I have a working hard drive platter that I could possibly use for something if i wanted.
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