its not that i dont believe you,but you see the difference.....cant be software's fault....
i use multisim v11
bjt version
opamp version
i use multisim v11
bjt version
An externally hosted image should be here but it was not working when we last tested it.
opamp version
An externally hosted image should be here but it was not working when we last tested it.
Try with 100R for R8 instead 1k, and 22R for R10 instead 220R, and use 2k2 for R12...
with this setup response was very well but with something pV at output...
i leaved the R12 at 2.2k and i played with values of R8 & R10 because there seems to be the problem....
the better response i got so far is with R10=5k & R8=100R....
FLow(-3db)=1.6Hz
Fhigh(-3db)=9Khz
still far from the best....
An externally hosted image should be here but it was not working when we last tested it.
BD243/BD244 work with voltage gain x5 (R8/R10), with 5k for R10 there is no enough gain. Try remove C11...
This is my very old amp (see post #99), there is no any files, but no need for new pcb design, just copy from old pcb.
I differ... I have had things simulate well in multisim but lockup LTspice. The operators knowledge doing the simulation , the simulator itself ,and the models used will determine the accuracy of the simulation. I just had LT predict my OPS bias point within 1mv from the simulation to the real thing. I knew almost exactly where to set the trimmer to get my 70ma VBias beforehand, no guessing .
I have also simulated classic designs and the simulator predicted the bandwidth and THD within a few % of the OEM specifications ... again, I had to use accurate models that matched the OEM's specs.
OS
Actually is not that multisim doing wrong but its difficult to understand its mind and how it calculate some things...
if i find time i will seperate the schematic into stages and i will see which stage doing this low-pass filter response....
i have already tested the opamp stage and i got clear response...
if i find time i will seperate the schematic into stages and i will see which stage doing this low-pass filter response....
i have already tested the opamp stage and i got clear response...
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Apex seems i begin to love this amp...the corrected clear schematic is this...
An externally hosted image should be here but it was not working when we last tested it.
with different R14 values(tried 22k,30k,56k) and different supply voltage, circuit gave 50W-200W on 8ohm with great frequency response....
I like F100 and use it many times in the past, I wiil build new version. It's great sounding amp and great reability amp but not popular in DIY, I think diyers don't like use OP in amps.
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