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Topics - Brymus

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Amplifier Discussion / LM3886 10 ohm resistor?
« on: November 18, 2009, 07:11:02 PM »
I was wondering at GGG they say use 10-12 turns of #22 insulated wire for the (inductor?) in parallel with the 10 ohm resistor (R5/L1) http://www.generalguitargadgets.com/pdf/ggg_lm3886_amp.pdf
Is this correct? Or does it need to be that resistive wire at StewMac which is so many ohms per linear foot?
Also what purpose does this arrangment serve?
I am almost ready to start my 3886 amp,just ironing out the details,thanx.

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Amplifier Discussion / Heatsinking the LM3886
« on: August 13, 2009, 08:11:00 PM »
Hi yet another 3886 question...
I read a thread here that pretty well detailed the options of heat sinking the 3886 chip
Except for a couple of things I would like to clear up before going further.

Is a TO220 insulator big enough (or should I say wide enough)for adaquate thermal transfer?
I have a couple of TO220 mounting kits w/the Mica insulators and was hoping to use that.
It just doesnt quite cover the whole surface to be sinked.

And what do you guys use for mounting these audio chip amps?

Like as in part #s and source I found some Keystone Mica insulators but the one with the largest surface  area was the TO220.

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Amplifier Discussion / lm3886 power supply question
« on: August 11, 2009, 02:19:45 AM »
OK I know the lm3886 likes a bipolar supply around 50VCT.
But I am having trouble with another chip amp that was supposed to use 12V 2A supply for 12watts could I run the Lm3886 on that and just get reduced output say around 15watts would be great at .01 %THD
I know it works on a straight DC supply as well, just wondering if 12V 2A is enough (isnt that roughly 20VA?) and what the output power would be around?
I got the chips cheap enough to experiment with too BTW so I dont mind not getting its full potential.

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The Newcomer's Forum / TDA1519B practice amp
« on: August 10, 2009, 05:18:18 AM »
UPDATE the problems were solved and soon I will update with schematics and finished build pics,I hope this thread helps someone else.

UPDATE here is the latest schematic working great so far.
http://i419.photobucket.com/albums/pp276/Bry928/SolidState%20Amps/12Watt-TDA1519B%20build/12WattTDA1519B_schematic.jpg
NEW SCHEMATIC COMING MUCH BETTER
CAB COMING SOON!

Here are some sound clips they sound like they were compressed for the server,if anyone wants the original MP3s PM me
http://vibecat.com/brymus

Hi all,I need some help I recently got some tda1519b chips and decided to make a guitar amp with one.
I followed the schematic in the application notes for the BTL at 12watts and simply replaced the LM386 in my Ruby type amp with the tda1519b using the right pins and a small heat sink.
I am using a 12V supply with a switch between pins 7 and 8.
The pre amp is a TubeScreamer topology using a NE5532 and a few FETS it sounds great going into the lm386 but the tda1519b not so much.
Also this thing is getting HOT I mean REALLY HOT!
I have a 8 ohm load and after a minute or so I am shutting it off cause of the excessive heat.I am using a fairly good size heat sink but maybe not enough.

I am powering the amp with 8 AA nihm cells putting out just under 12V
And for testing I am using two 16ohm 5watt spkrs in parallel from an old TV.

After almost 5hrs of googling this http://munkey.hopto.org/projectsdir/audiodir/simpleamp.php  and 2 TV schematics are the only schematics I can find.
I have it like this but its not right can someone show me what I am doing wrong?
I have been trying all day to make this work without any luck.
Is my input V or my input Z wrong? If it works great with the 386 chip?

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