so will I make R1 to 470 ohms and thats all?
It depends on sensitivity that you want. You may short it completely for more sensitive input. I suppose it was there in the original amp to apply feedback from output of the amp (one more resistor is needed in such case, from speaker output to R1).
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100k is fine...this resistor will look like it is more than this value by virtue of its connection....
i got cockeyed....i was looking at R11, you can connect this directly to ground so you don't need the input cap....
R1 can be a short if you are not using global negative feedback like wavebourne said......or connect the 10k resistor to the 470ohm R1 instead...
i got cockeyed....i was looking at R11, you can connect this directly to ground so you don't need the input cap....
R1 can be a short if you are not using global negative feedback like wavebourne said......or connect the 10k resistor to the 470ohm R1 instead...
Okay sir Thanks...i will try both options...short it and also try NFB...whichever is better.
If I ground the 1meg input resistor and connect a 10k resistor from spkr to the point between 500 and 470ohm resistor as nfb will it be okay?
You will get 10k/470+1 amplification factor (about 20) from input to output. That means about 300 mV sensitivity.
You will get 10k/470+1 amplification factor (about 20) from input to output. That means about 300 mV sensitivity.
Yes sir, that's what i have in mind, gain of 20 or 25. I use the solid state tone control from the old pioneer with a lowish gain. Is it advisable to use Solid state tone control or tube tone control?
Project update:
Gain problem is solved however bass tones are crap...mids and highs was good...what seems to be the problem?
I use a 56v, 3a power trafo for PSU...i use quadruppler with 4 1000uF/250n caps then resistor and 330uf/450v cap again for the final HT of +262 volts. OPT is good around 10w-15w.
Was the PSU provide enough current? the idle current as measured is 70ma per channel.
Gain problem is solved however bass tones are crap...mids and highs was good...what seems to be the problem?
I use a 56v, 3a power trafo for PSU...i use quadruppler with 4 1000uF/250n caps then resistor and 330uf/450v cap again for the final HT of +262 volts. OPT is good around 10w-15w.
Was the PSU provide enough current? the idle current as measured is 70ma per channel.
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