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Old 8th December 2008, 12:22 PM   #111
sneih is offline sneih  Indonesia
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ok bro, i will update as soon as possible.

btw can i replace 220uF with any bigger caps?
for the better sounds?

thx
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Old 8th December 2008, 02:03 PM   #112
sneih is offline sneih  Indonesia
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double
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Old 8th December 2008, 02:10 PM   #113
Khron is offline Khron  Romania
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This might be a bit more neat
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Old 8th December 2008, 04:26 PM   #114
sneih is offline sneih  Indonesia
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hmm nice n simple layout than i make before....

imho, can you move 220uf n resistor behind lm 1875 more into for easily attached big heatsink? i have a same problem with pcb i make before!!
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Old 8th December 2008, 04:41 PM   #115
Khron is offline Khron  Romania
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Something like this, i guess. But then you'd have to mount the 22k resistor on the bottom of the board
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Old 8th December 2008, 08:02 PM   #116
sneih is offline sneih  Indonesia
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hmm good alternatif
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Old 8th December 2008, 09:37 PM   #117
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Quote:
Originally posted by sneih
ok bro, i will update as soon as possible.

btw can i replace 220uF with any bigger caps?
for the better sounds?

thx
But, this isn't what I was talking about.
Actually, I was talking about the place to ground the speaker.

The speaker ground is actually "speaker return" because almost all of the force that's sent to the speaker does come back into the amplifier, and we don't want that accidentally getting into either of the amplifier's inputs--so don't put speaker return ("out -") on the amplifier board.

You also get better bass if you provide the strongest possible reference to support the speaker's signal, and the strongest reference is the 0v (ground) output terminal of the power supply board. See also "Power Star Ground"
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Old 9th December 2008, 12:56 AM   #118
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Quote:
Originally posted by sneih
ok bro, i will update as soon as possible.

btw can i replace 220uF with any bigger caps?
for the better sounds?

thx
The optimal size will depend on which chip is in use, and many other factors, as well.
Good options include 220uF or 470uF.
Use whatever sounds clearest and use whatever power circuit doesn't promote ringing bass.

Pin compatible chips include:
National Semiconductor LM1875 > Use LM1875.pdf
or
SGS Thompson, ST, TDA2050 > Use TDA2050.pdf
Clone LM1875* > Use TDA2050.pdf
*The clone LM1875 does not differ from the clone TDA2050 except for the label.

Recently, I got the embarassing opportunity to learn more about this issue.
No speaker was harmed, but it was a near-miss. I thought it was a wonderful sale price; however, what I received wasn't what I had intended to purchase. There was more power and more bass, all of inferior quality.
Solution:
Whenever power output per voltage used is out of spec for LM1875.pdf, then use this (TDA2050.pdf):
http://www.datasheetcatalog.org/data...onics/1461.pdf
1). Don't exceed 26.7vdc rails (abs max for clone chip), and please consider using lesser voltage.
2). The optimal components for use at the amplifier board may be different when the chip is a different model.
3). And, keep the "NFB cap" (don't omit), because speaker safety is a primary concern for the less-durable chips.
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Old 9th December 2008, 07:25 AM   #119
sneih is offline sneih  Indonesia
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i just update new layout, maybe like this?

Click the image to open in full size.
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Old 9th December 2008, 08:09 AM   #120
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Maybe some problem attaching a heatsink?
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