I tested with 33uh. But only change is tgat i used 1m instead of 10m on pin 2 to 1 of tl074. Will that hurt efficiency that much?. And did you do resistor load testing? What efficiency did you get?
use all parts exact as at the schematic i told you, that is the 10m should remain 10mega . the inductance that is the one i saw has a significance change when increased. by the way what type of inductor are you using?
Indeed very simple, but notice that there’s no feedback loop. One has to consider its hifi-ness.
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To all that has build it and since this thread has grew a lot, which schematic is considered the most "final" version? Or at least the most mature? For some definition of 'final' or 'mature'.
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To all that has build it and since this thread has grew a lot, which schematic is considered the most "final" version? Or at least the most mature? For some definition of 'final' or 'mature'.
i still use the tl074 , the amp is nice but if you are making it make sure you use bc337,bc327 and tl074.
updates on my amp. firstly i rectified the transistor arrangement on the dcp section , then i removed the overcurrent protection and remained with the dc protect. (I should have used an optocupler at the ocp instead of the transistor
hi all , i have made many pcb versions of this amp ,
i still stick to the original schematic in the above link.
the thing i found interesting in this amp is that it requires original tl074/084 and bc327 and bc337 . if you compromise in this area it will consume alot of current at idle an produce hf noise.
my question is can i use two lm339 instead of tl074/084 and which other transistor can i use to substitute bc337 and bc327
vvv vvv my current project vvv vvv
Attachments
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IMG_20210322_195354_314.jpg -
IMG_20210322_195027_990.jpg -
IMG_20210322_195039_540.jpg -
IMG_20210322_102949_683.jpg -
IMG_20210322_103048_038.jpg -
200wt strd ver1.2 dc prtc long bom.pdf
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GerberFiles 200wt strd ver1.2 dc prtc long gerber.zip
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200wt strd ver1.2 dc prtc long pcb bottom.pdf
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200wt strd ver1.2 dc prtc long pcb top .pdf.pdf
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200wt strd ver1.2 dc prtc long schematic .pdf.pdf
hello all , i have made my latest version of this amp , i opted for a through hole ic due to challenges in getting a geniune tl074/84 smd . imagine the smd also have issue ,
A not original ic works fine in preamp,eq, crossovers etc , but can't work well in this class d amp ,
with this amplifier it works but the amp produces a lot of hf . but when i use a good geniune ic the hf noise reduces and the amp does not draw a lot of current
but a geniune tl074/84 works with no issues at all .
here is my project and pcb files . have fun fam
, A not original ic works fine in preamp,eq, crossovers etc , but can't work well in this class d amp ,
with this amplifier it works but the amp produces a lot of hf . but when i use a good geniune ic the hf noise reduces and the amp does not draw a lot of current
but a geniune tl074/84 works with no issues at all .
here is my project and pcb files . have fun fam
Attachments
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200wt strd smd large ver1.25 dc prtc long pcb bottom.pdf
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200wt strd smd large ver1.25 dc prtc long pcb top.pdf
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200wt strd smd large ver1.25 dc prtc long schematic.png -
IMG_20210401_181716_986 cccc.jpg -
IMG_20210401_220756_877.jpg -
IMG_20210401_220745_900 ccc.jpg -
IMG_20210401_181533_308 cccc.jpg -
IMG_20210401_181758_239 ccc.jpg -
200wt strd smd large eagle pcb files.zip
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It is quite slow, but it doesn't suffer from phase reversal. Of all old opamps it is closest to a comparator.can lm324 work ??
I didn't have opportunity to sit and rework the schematic yet, sorry.