I purchased my Aleph 2 monoblocs based on KK PCBs as kits about 10 years ago. I immediately built one , but have only now started on the 2nd. I have just noticed that when I built the first one I did not fit R27 ( 221ohm) which, I think is R15 on the original circuit ( highlighted on attachments). I am almost certain that I did not fit R27 based on the advice of the kit seller, but I can not remember the reason given. So some advice please:
What is the function of R27 and what is the impact of not fitting it?
Is it now recommended not to fit it to the KK boards?
What is the function of R27 and what is the impact of not fitting it?
Is it now recommended not to fit it to the KK boards?
Attachments
that transistor is practically overcurrent limiter for lower half of amp , and without said resistor - it's nonfunctional
if you are having some salt between ears , you don't need it
if you're lacking in salt between ears , even that protection isn't enough
if you are having some salt between ears , you don't need it
if you're lacking in salt between ears , even that protection isn't enough

If I decide not to have current limiting and do not fit R27 can I leave Q4( current limiting transistor ) and the 150 ohm resistor that forms the voltage divider with R27 still connected on the PCB without any detrimental effect on the amp?
Some people do think that the existence of a transistor protection circuit spoils the cows milk...


Nelson, Thank you for taking the time to respond. I have decided not to retrofit R27 ( R15 in original circuit ) and leave the over current circuit disabled.
It is playing music very well without the resistor, but I will test it for a longer period to ensure all is well.
No big deal. Protection in the original circuit is for consumers who are not
able to avoid shorting the output. Fearless DIYers are exempt.
able to avoid shorting the output. Fearless DIYers are exempt.
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