If anyone wants a quick try with pcbway for 5usd for 10 PCB with 12usd shipping, here is the 2 sided PCB for apex super gain clone. 50mm x 60mm.
Rail caps are 10mm dia and other 100uf electrolytics are 7mm dia. All film/ceramic caps have 5.08mm pitch.
Reg
Prasi
assembled 1 channel to see how it sounds. powered up fine without glitches first time.
Sounds very good on test speakers, used a opa2134.
here are the pics. Thanks Mr. Mile for the circuit. Am I the first one to test this particular ckt?
I might put this one in my boom box that currently uses a dayton DTA-2 class T amp.
regards
Prasi
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assembled 1 channel to see how it sounds. powered up fine without glitches first time.
Sounds very good on test speakers, used a opa2134.
here are the pics. Thanks Mr. Mile for the circuit. Am I the first one to test this particular ckt?
I might put this one in my boom box that currently uses a dayton DTA-2 class T amp.
regards
Prasi
Nice work,
Regards
Dear Mr. Mile (and other members),
I have seen a lot of designs of LM3886/3875 but there are two opinions - one claims that these "Chipamps" are "rugged" and safe to use without speaker DC protection circuit. Mr. Mile loves rugged designs and always (99%) uses DC protection in his designs, but in this design I do not see it. Why?
Other claims that it should be used without compromises.
What is Your opinion/experience?
I have seen a lot of designs of LM3886/3875 but there are two opinions - one claims that these "Chipamps" are "rugged" and safe to use without speaker DC protection circuit. Mr. Mile loves rugged designs and always (99%) uses DC protection in his designs, but in this design I do not see it. Why?
Other claims that it should be used without compromises.
What is Your opinion/experience?
if the stage ever tries to output a high proportion of high frequencies, then the Output Zobel passes much of this and the Zobel resistor gets hot.
If you test using 10kHz (or higher) squarewave you will probably burn out a 1W Zobel resistor whenever you turn up the signal level.
For testing purposes you need at least 3W and preferably >=5W
If you test using 10kHz (or higher) squarewave you will probably burn out a 1W Zobel resistor whenever you turn up the signal level.
For testing purposes you need at least 3W and preferably >=5W
Thanks Andrew T for your kind reply.
I just want to make a simple home stereo...
not for testing purpose.
my question was....which one i should use as
jobel resistor?
The parts list and pcb top(apex gainclone 1.0)
has two different value resistor.
Parts list--4R7 1watt
Pcb top--10R 0.5watt.
And please suggest voltage and ampere rating
for 4ohm & 8ohm load both.
Off course for stereo.
Regards.
I just want to make a simple home stereo...
not for testing purpose.
my question was....which one i should use as
jobel resistor?
The parts list and pcb top(apex gainclone 1.0)
has two different value resistor.
Parts list--4R7 1watt
Pcb top--10R 0.5watt.
And please suggest voltage and ampere rating
for 4ohm & 8ohm load both.
Off course for stereo.
Regards.
how much supply voltage & current will be good for 8ohm & 4ohm load?
Regards.
+/-28V for 4 ohm and you can go upto +/-35V for 8ohm.
http://www.ti.com/lit/ds/symlink/lm3886.pdf
Boucherot resistor 4R7 1watt or 10R 0.5watt?
See here: LM3886 Chip Amp Stability Analysis
how much supply voltage & current will be good for 8ohm & 4ohm load?
Here: LM3886 Output Power
Tom
Dear nirupambhowmick,
10R and 4R7 both will do the Job.
I would recommend to use 1-2 W. Sometimes 4R7 is more preferable.
Thnk u so much.
+/-28V for 4 ohm and you can go upto +/-35V for 8ohm.
http://www.ti.com/lit/ds/symlink/lm3886.pdf
Thnk u.
Thnk u friend. Will see.
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