Thanks, you are correct. Here are new scope shots with the 1000uF 16V installed in C7.
Attachments
Just trying to understand amp behaviour in bass region. BTW, clipping profile looks as good as any amp.
Reg
Prasi
No, I couldn't hear any difference but it was clear on the scope. How much music has much 50hz content? Make no mistake, this is a fine sounding amp. Definitely worth building.
Terry i ask about bass responce because this range isn 't the good point for 1058,162
This is my experience.
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Strange, that has not been my experience. P101, VSSA, TubSuMo, Slewmaster mini and now FX8, all with great low end. This FX8 has some of the flattest 50hz square waves i have ever seen. There is a tad of overshoot in the higher frequencies. I used 100p per the schematic. Mile's layout seems to use 330p. I don't have those in stock so i stayed with the 100p. I'm not sure if that is the reason.
Mouser doesn't have the "E" version of the C3503, only the "D" version.
Can this be used without issues with the "E" version of the A1381?
Thanks...
I bought e from abroad in the hope of solving this in an NX.
Fraid I still have unmatched devices, because the overlap between the wide spread allowed in the specification means that the base currents still don't match.
Fraid I still have unmatched devices, because the overlap between the wide spread allowed in the specification means that the base currents still don't match.
I think you can. NFB should take care of minor differences. I only matched the input pair. If I feel ambitious I will try it.
Here you go. BTW, I used Prasi's layout for my template. I want to give him the credit.
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.mixing the hFE results in a difference in base current when the devices pass the same emitter current.
That mismatch in hFE will happen whether the devices are both D, or both E, or from D & E.
It's the difference in base current that matters.
Will the circuit perform as well if the base currents are not closely matched?
The designer has not told us what effect on performance there would be if the base currents are not matched.
