Just clocked few 'virgin' hours... my very first tube preamp!
This is based on diyparadise's 5687 preamp..
Still sitting on a 'testbed', will make proper casing as I do not know how it would turn out. Glad to say, I am fully satisfied with the SQ. Had some problems with humming and all but it's a good learning process after all these years with solid state. Truly rewarding!




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For OB I'm suggesting you to spends time to read some of the method in Quarter Wave website as a guide

Nanhifi long time no see..you're sure one busy man

This post has been edited by gabanyayaya: Jul 18 2010, 04:09 PM

How to build a 300W per channel of amplifier ? And what things should I have to build this amplifier .

You start with a schematic(hint:search the internet forums).
Apart from getting the required cmponents and related hardwares, you also need some tools.
And some soldering skills with some understanding in electrics and electronics, like Ohms law etc.
You can also start 'small' by assembling a 'kit' and progress from there...

300W is a pretty big number, especially with complex load like speakers (they are sorta complex) you have to seriously put in a lot of effort for doing so.

Like I've previously said, if you're asking how to do something this hard, you're probably not ready yet. Then again, I'm not discouraging you from doing so, but assuming you're quite new to this and is willing to go through hell to achieve your happiness, why not?

protip, burning amp2 from nelsonpass.

Any recommended website for schematic ? And how to check the wattage use by a tweeter ?

posting this so future builders can benefit from it.

this might not be largely relevant for most people but I've went through quite a lot of expensive shit while building the Gamma1/Gamma2. I know a lot of guys in the circle f***ed up too lol.

Yes, the issue is with soldering the many little pins of the little DAC chips (WM8741 and SR4192 is the hell) and the processor chip.

I've been using soak and depump method (old LYN diyer style) for quite some time. However the problem with this method is that if your pump is too strong, and the pads are weak, you'll rip off the pads and/or "bend" the pins. Damn risky, this is a stupid method come to think of it. DO NOT DO THIS. My apologies to those who I've recommended this method to previously. It works for bigger soics, but for smaller SMDs, f***.


The best method I've recently learnt:

Requirements:
1x bottle of no-clean flux (no clean is better so you can spam the hell out of it)
1x desoldering wick (you'll be amazed how well it works for SOIC and tiny pads, I used to think it's useless for most applications because the heat is always dominated by the larger pads and through hole parts. You absolutely need this for SOIC since the tiny pads won't eat away most of the heat used for the wick)
1x soldering iron with a fast heater (ceramic heater)
2x balls of steel.

Steps:
1) spam flux on pads.
2) apply a thin layer on one of the pads, preferably the 1st or last pin (any edge pin would work).
3) melt the layer with iron, and align the component to the pins. Finalize alignment by fixating the solder. Make sure you press down the chip again while melting the solder layer so that all the pins are tightly pressed on the pads.
4) Spam flux on pads (together with the pins)
5) now apply some amount of solder to your iron, and sorta "brush" the pins by kissing it one by one. Caution, do not put too much solder on your iron because you'll accumulate a huge blob on the pads. This also means that you only need a small amount on your tip and it'll last for quite a number of pins and pads before you fill more. Also works even with standard sized tips. Awesome flux is awesome.

*If you've accidentally made a bridge/blob, use the soldering wick (remember to soak soldering wick with a bit of flux). IT WERKS TRUST ME.



GOD, I"VE BEEN SO FRUSTRATED, NOW I"VE LEARNT MAI LESSON, WHOAOMG.

This post has been edited by LittleGhost: Jul 27 2010, 07:14 PM

luckily i din follow..XD

hey..thanks for the tips...btw i didnt get for "2x balls of steel"..

(=______=)

EDIT: Still have not fix your stuff HAHAHA. (currently fixing chchyong's and tention's unit)

---

Added on July 27, 2010, 7:46 pmhttp://www.youtube.com/watch?v=IE3KdcTgrno

DUKE NUKEM: BALLS OF STEEEEEEELLL

This post has been edited by LittleGhost: Jul 27 2010, 07:46 PM

i think im gonna go haywire if i follow this thread..
it simply does NOT makes sense.. rofl~

Nice one LG!
yep.. I got it! (2x balls of steel)

This post has been edited by jazzy939: Jul 27 2010, 08:17 PM

How to make the amplifier with 300 W ??

we've already gave you the appropriate places. Burning Amp 2 is one of the few big guns you should consider. Also, DIYAUDIO.

300 W is a big number, it's very hard to find stable and solid DIY designs out there. If you're asking how to, you're not really ready yet. It's like asking how to build a jet plane out of no where.

How about 100W amplifier or 150 W amplifier ?

Build urself a gainclone from sratch.

Why the need for 300W amp? sub-woofer amp?
Here, I found one:

http://www.eleccircuit.com/300w-power-ampl...-by-transister/

My advice to newbies; start small like 10W or so.. heck there is even 1W amp kit in JP.
Agreed with LG,stable 300W amp designs are kinda hard/difficult to find, but of course there are ready made modules in Class D that goes up to 1000W and above. 100W-150W are aplenty, can find a few in JP.
The highest wattage I made was 40W+40W which was powerful enough to drive my floorstanders..

I have parts and boards for the LM3886 GainClone if you want. I decided not to build it as I found something better...

This post has been edited by jazzy939: Jul 28 2010, 08:41 AM

I will start to make small watts amplifier . Any guys can suggest me , which type of solder wire is good to use ? And should I have a soldering station ??

Use the normal variety that you can find in the shops... buy a good and affordable soldering iron. If you can afford a soldering station, why not. Not that it makes much difference to the soldering job, it's the skills and techniques acquired that makes the difference!. I use Antex and Hakko irons.

station is better if you're a perfectionist. Otherwise, a single ceramic heater type solder iron will do the work. (Hakko Dash). As for the solder wire, I personally use Kester euthethic blend 63/37, but kesters are hard to find locally. You should use the euthethic blends over the tin leads because they are simply much more easier to work with. Plus they produce great results consistently.

Flux just get a big bottle of the no clean flux from the big distributor at Jalan Pasar.

These are good investments if you're intending to go far into this hobby.