Gain issue with a small buffer

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Hi i was trying to sim the famous JC2 by Mr Curl and failed
Changing some parts i have ended with the circuit attached Now it reduces the input voltage of about half
Is there a way of reaching unity gain ?
the idea is using it as a buffer maybe with 2 x 9V batteries
Thank you very much to all
 

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Joined 2009
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Hi yes sorry i did not know about the schematic but i found it on the web here https://www.diyaudio.com/community/attachments/jc2schematics-jpg.509235/
One other thing: you look at an FFT. There are many ways to get the wrong level out of an FFT. When you look at an FFT of the input signal, do you see the level you expected?
I have to be honest I dont know how to expect The gain is slightly less than one Just one question When the dissipation of a transistor is almost zero it means that the circuit cannot work ? in the order of picoW :unsure:
I am sure there is something wrong here I was trying to use the original line stage as a buffer I do not need gain Also because with gain comes also pain
 
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What do you need a buffer for?
Hi to drive a power amp stage after an attenuator
Not sure why you post a question but do not show the schematic.
I am very sorry i did not want to do something against the rule I thought that the circuit was pubblic domain ? the link is here
https://www.diyaudio.com/community/attachments/jc2schematics-jpg.509235/
it is called output amplifier module
as i dont need gain i was trying to wire it as a buffer Maybe changing voltages and values ...
 
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Hi sorry if i am trivial but i am noticing that to have a power amp with high sensitivity and high input impedance simplifies the job of a driving buffer immensely
I would say that high sensitivity is more helpful than high impedance
In the past i ruined a small amp trying to reduce its gain just changing the feedback resistor (not the one to the ground)
The idea was to use it like a power buffer (power amp with low Vgain) with an headphone amplifier instead of a line preamp
Then i could have used a pair of headphones to select the HP amp on the basis of its sound Even a tube one (my feeling is that headphones are much more revealing than a normal hifi system with speakers)
Now i have changed my approach and i am moving in the opposite direction quite convinced that when a buffer is asked to push only let's say 500mV in a decently high impedance (in this case 5kohm) the result can be very good indeed in terms of THD at least
 

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  • LM317 buffer with CCS.JPG
    LM317 buffer with CCS.JPG
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