share mine
Bridged
C_in : 470n
Gnd signal lifted with 4R7
33k + 47u for muting delay.
C ripple rejection 470u.
Vs ~ +16Vdc
An externally hosted image should be here but it was not working when we last tested it.
Bridged
C_in : 470n
Gnd signal lifted with 4R7
33k + 47u for muting delay.
C ripple rejection 470u.
Vs ~ +16Vdc
a little bit different scheme, but similar: (I've no drawing tool at now)
R1 = 33k (with 22k I'm still hear thumb)
C4 = 47uF
C3 = 470uF
C6 = 4700uF
input Ground and pin #3 were separated with 4R7 from the main Gnd (pin #7 and #11)
on my pic, you might be wondering why there is a lot of resistor arround the input (and two jumper). at the time I design the layout, I'm just thinking about the flexibility of the amp to be used as single-ended / bridged nor bridge-parallel(if possible) with additional component in the output line.
the sound is good, the guitar seems moore "fat" than my LM1875, although not as clean as LM1875. Bass is also tight.
sorry for the PCB, it's a hand made (you can see it from the silk and the text).
regards,
R1 = 33k (with 22k I'm still hear thumb)
C4 = 47uF
C3 = 470uF
C6 = 4700uF
input Ground and pin #3 were separated with 4R7 from the main Gnd (pin #7 and #11)
on my pic, you might be wondering why there is a lot of resistor arround the input (and two jumper). at the time I design the layout, I'm just thinking about the flexibility of the amp to be used as single-ended / bridged nor bridge-parallel(if possible) with additional component in the output line.
the sound is good, the guitar seems moore "fat" than my LM1875, although not as clean as LM1875. Bass is also tight.
sorry for the PCB, it's a hand made (you can see it from the silk and the text
).regards,
The important thing is...
to have a hefty power supply. 12Volts at 5 Amps according to the spec sheet. I've got one from a BA745 I found in the someone's trash but I haven't done anything with it. But I think I will build it as a 4 channel amp. And its a good idea to have a hefty heatsink as well.
to have a hefty power supply. 12Volts at 5 Amps according to the spec sheet. I've got one from a BA745 I found in the someone's trash but I haven't done anything with it. But I think I will build it as a 4 channel amp. And its a good idea to have a hefty heatsink as well.
I mean pin #3 is the signal(input) gnd in the chip, while the input Gnd is the Gnd where your signal came in (like from input connector which is isolated from the chasis).
you don't have to connect signal Gnd and main(power) Gnd via 4r7. but those resistor will help (a little bit) to give the signal line cleaner grounding.
yes you can use a 16V rating cap for pin #4, its only 1/2 the supply voltage.
sorry for my bad English
do you mean "then" not "than"?
it could be from your PCb layout. maybe your input line way too close to the output line.
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