Hi, I have a loudness circuit which need to reduce "output". how may I achieve this by fixed resistors by around 6-9db? How to calculate values?View attachment PM6006 Integrated Amplifier Service Manual PG9.pdf
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Changing the feedback network could cause high frequency instability.
A series 50k to 100k before the volume control would do this safely.
A series 50k to 100k before the volume control would do this safely.
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Thanks for your speedy reply!
if I put a 50K resistors after C2503/2504 (100V 0.1uf), would it not change the original circuit when in "no loudness mode"?
if I put a 50K resistors after C2503/2504 (100V 0.1uf), would it not change the original circuit when in "no loudness mode"?
If I want to remove the "treble lift" in the loudness circuit, should I remove and short C2501 / C2502?
The "Loudness' Circuit is oftentimes what they call the hearing curve compensation. It is a special dynamic type of EQ that adjusts the sound to the human hearing sensitivity when levels are below a certain threshold. Not enabling it should have it disabled. It is not active when it is not enabled. 🙂
Switch the 'Loudness' off and use the bass eq to boost instead.
I see no need to go inside the thing.
The Loudness Comp is supposedly proportional, so another solution to your concern could be to just play it louder 😛
Sorry for my late reply as I was busy with work. The amp now sounds better so far.
I would like to express my thank everyone for their advice on this thread as I have gained much on understanding the circuit.
Last question : What does changing R2501 / R2503 achieve, that is after adding 50 K adjustable resisters after C2503 / C2504.
Best Regards.
I would like to express my thank everyone for their advice on this thread as I have gained much on understanding the circuit.
Last question : What does changing R2501 / R2503 achieve, that is after adding 50 K adjustable resisters after C2503 / C2504.
Best Regards.
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