http://www.circuitsonline.net/forum/view/36929/2/tda2005+layout

A little down on this page you'll find schematic and layout for a TDA2005 amp.
Look on the middle of the page for where it says :


"Een warme avond verder:
Schema in pdf
Layout in pdf
Componentenopstelling in pdf
Componentenlijstje
Schema/layout voor Ulticap/Ultiboard in zip"

ApexJr, I'll try with one of the 21-0-21 trafos. Line voltage where I live is just 225V, and since I'm only planning to use the amp at home it should be OK.

that are some great prices, ApexJr, but doesen't those transformers put out a little to high voltage?

Just to be absoloutly sure, I wanna check with you guys (once again...) that I'm ordering the right transformator for my stereo LM1875 kit. Don't want to buy a trafo for $100, and find it's not suiteable for the job.

This is what I'm looking at: http://www.elfa.se/pdf/56/05612569.pdf
Would this be good for my purpose?

Looking at the prices, I see that transformersare way cheaper over at parts express than here in Norway. Unfortunatly they wanted to charge me $79 for shipping it via USP Express. That got me thinking about ordering it to one of you guys, and having you to ship it with USPS to me for way cheaper. If anyone feel like helping me out with this, please let me know.

Quote from: ANDREW_SHOULD_DIE on March 11, 2007, 03:05:37 AM
thanks.....
i need pictures though (laughs)
i am pretty hopeless when it comes to reading, and scematic and stuff,...
i can only really work off pictures and diagrams....

any help?

You shold spend a few minuttes reading up on schemtics, as they are the key to succesfull builds. I guess you could go and build a preamp from a layout, but you will have problems deuggng it. you can find layous over at www.diystompboxes.com

On my site you'll find how I added a piezo-pickup to a strat. Th same pincip used on acoustics. www.syndromet.com

Quote from: jedisteve on March 07, 2007, 02:10:01 PM
This looks like something I might want to build....would you place the speaker where the rhetostat is?  Or is it connected some other way?  Also, where could you buy a speaker for a small amp like this and is there any specific kind of speaker I should be looking for?  Thanks.

Like all other guitaramps, this sounds best with a dedicated guitar speaker. These kind of speakers are built to sound good with guitar frequenciez, though I'we heard people have had success with car speakers and HiFi speakers with the Gem, too.  I tried some 4" car speakers with my Ruby, wich is a very simmular design, and they sound like *s!!t*. Generaly, a guitar speaker should be at least 8" to be able to reproduce the guitar frequenzies correctly. Google jensen Mod speakers for some really cheap and really good guitar speakers.

The speaker connects with the positive wire to where the schematic says "OUT". The negative wire go to ground.

You'll find perf and PCB layouts at http://www.runoffgroove.com/littlegem.html

It's a monster.....
http://www.youtube.com/watch?v=msO1_lRhZhY

Quote from: Fras on January 25, 2007, 10:39:46 AM
ok, thanks a bunch for all the tips!^^

EDIT: Umm... Where can I find some schematics? I've looked around a little, and only found ones with either tubes or transistors... Where could I find some with OP's? =D

There is a lot of good schematics in the schematic section of this page too. Also check out the datasheets of the chips you'd like to use. The usaly have schematics included. Sometimes even PCB layouts.

or check out www.41hz.com for simular kits.

From what I'we read it's supposed to put out about 15 watt, but I understood that is with quite a lot of distortion. I guess 8-9 watts is more correct for a clean tone.

More info here http://www.si5.com/products.php?pID=4005

Have any of you guys tried a class-t amp for guitar. I got my SI T-amp from think geek today, and it gets great rewievs from the hifi-people. it cost 29$, wich is next to nothing. The circuit seems super simple, it recuires 12 v dc, and the chip don't need heatsinking. It is based on a Tripat 2024, wich is awaileable from PartExpress. Anyone tried one of theese with guitar? Looks like an easy buid, or an easy rehouse if you buy the SI version.

http://www.ssguitar.com/index.php?topic=77.0
You'll find the PCB here. It seems to be ok, but I guess I installed the chip the wrong way or something. I'll give it another try when I get the hold of a new chip.

If you carefully open your tank, it should be some springs in there. Make sure none of the springs are loose, and that they are nice and tight. Since you get reverb, it is more likely that there is something wrong with the mecanical part of the reverb and not the electronics. It could also be worth a try to add some sort of booster between the tank and the rewerb, to amplify the signal and make the springs vibrate more.

Whatever you do, don't change your reverbtank for an electronical reverb. Then you're better of getting a new reverbtank.

It's hard to teel what do with the amp without a schematic. There is probably some clipping diodes in there, or a OP amp, that delivers the crunch, but you have to be carefull switching things in there.

I guess your safest bet would be a good distortion or booster in front of it. I'we tried that amp myself, and it sounds quite good. I bet it would sound lovely with a Dist+, tubescreamer or ROG Eighteen in front of it.