The Boominator - another stab at the ultimate party machine

[wurtel]

So, anyone who could provide some help with http://www.diyaudio.com/forums/class-d/104402-boominator-another-stab-ultimate-party-machine-292.html#post3054645
]the switch mentioned in this previous post[/url], please?

[danielwritesbac]

Originally Posted by Rolschau

I just tried and it is a lot louder with my regular amp. Maybe I should just try buying a new Ta2020.

Necessarily, a Class D "No Soldering" needs adjustable gain switch provided if you plan to use it with digiplayer/iPhone.
For example:
Sure 2 X 25 watt TDA7492 Class-D Audio Amplifier
"Gain adjustable–four fixed gain settings: 25.6 dB, 31.6 dB, 35.1 dB and 37.6 dB"
Isn't that nice? Just flip the switch. No soldering required


P.S.
However you could fix the amp you already own instead of buying another.
If soldering connections is difficult for you, then try this stuff:
1). (the "easy button") Gel Flux for soldering success. Definitely a must-have!
2). Big heat for big things; small heat for small things, dual wattage iron
3). The undo feature. Can also be used with Gel Flux to fix old stuff
4). 63/37 and 62/36/2 don't shake loose later, so your work is more durable than with 60/40

[bekutori]

A couple of days ago me and my friends were pretty much done with our boominator (except painting etc)... Well atleast we thought.

We went in the beautiful weather to test the thing out. We were very happy with the sound and build and enjoyed pumping music, well at least for an hour or so...

Then happened the nightmare. When I was going to change from one iPod to another the sound just died with a pop (like someone cut the power), and saw some dark smoke rise from the amp. "This is not happening" was my though and disconnected everything as soon I could. I could immediately smell that something had burnt and was soon going to see that a "copper band" (or what you call it) in the circuit board (amp6-basic) had been burnt into to pieces. The Tripath-chip was not hot and didn't smell burnt, so I don't think it got damaged.

I really have absolutely no idea what would have caused this nightmare, so I'm turning to you guys and would be so glad if anyone could help me out with this situation. Why did this happen? Is it possible to solve or should I just buy a new amp? And what can I do to make sure it won't happen again?

I did not solder the amp6 my self, I bought assembled from profusionplc.
(41Hz-TA2020)

The cable between our SLA-battery and the amp was soldered by someone who pretty much works with soldering. He also soldered a circuit breaker between the SLA and the amp (on the +cable). He did though have to resolder like three times on the board as the cable was to thick and keeping breaking when "peeling" it, calling it "probably the most annoying soldering I've ever done).

The SLA-battery was a 12V 12ah.

Here are some pictures (clickable) of the amp6, would be really appreciated if you could take a look and maybe help us on this thing.


Thanks and all the best!

[bekutori]

Whoa, the pictures got way too big... It seems I can't edit my post, but if admin can resize the picture it would be much appreciated.

Sorry!

[Pano]

Done

[bekutori]

Thanks!

[Campino Morten]

Did it blew the fuse?
Is it the copperband that connects the main cables, that are burnt into two?
Is it impossible that something could have made a shortcircut where the mains are soldered? By something, I think about loose metal objects near the amp or maybe the main wires?

[Saturnus]

Pretty easy to see what happened. It was a bad solder. Maybe a few stray wires but anyways it shorted the input power before the fuse. Nothing has happened to the chip most likely though.

This is why you should always always always have a fuse on the battery.

How to fix it. Easy. Clean the area up and resolder it properly. Yes, it takes a long time to solder on double copper thickness boards and thick power wires but your friend should have known that. Or just cut it off and buy a DC barrel connector with terminals already on them and use the DC plug instead. Usually costs about $2.

After that is done, you take a razor and remove the power ground to signal ground strip that has burn off the pcb (the exposed copper strip). It's made very thin on purpose in order to burn through if this happens. then you take a very very thin piece of wire and coonect the two points again with the holes made for it.

[bekutori]

Thanks for your great answer Saturnus. I've read it through some times now and I'm pretty sure I'm following what your saying.

Glad it could be fixed (even seems as a pretty easy fix). Yea I think will go for a DC connector with screw terminals and use the DC plug instead.

For now, just one question: when you say a "very very thin piece of wire", what exactly do you mean? Like one single copper wire from a speaker cable? And how should we then connect the two points? Solder on both the holes?

As you can hear (see) I'm far from an expert on theese things. Really appreciate you helping me out!

All the best

[Saturnus]

It has to be isolated wire but yes the thickness has to be similar to a single strand of wire from a speaker cable.