Loudness Calculation

I'd like to apply loudness on my integrated amp. In fact, my amp already has a loudness function but it didn't satisfied me. It boosts +8dB @ 100Hz and +6dB @ 10kHz. I thought it was too much for me. Going to my car, I found my head unit satisfied me. It specs is +6dB @ 20Hz and +3dB @ 20kHz. Back to my home, there are bass/ treble knobs available on my amp which are boosting at the same frequencies as its loudness; 100 and 10kHz, also have dB scales on the face-plate. In order to replicate the car's hifi, how much dB should I turn up the bass/ treble knobs? Thanks in advance
 
The curves are different, so one can't duplicate the other. You could change the capacitors in the tone
controls of the integrated amplifier to alter the design frequencies, and make them more similar to
those in the car. You would make the bass capacitors larger, and the treble capacitors smaller.

You could certainly try to adjust the tone controls as-is to moderate boost levels, no more than what
you mention, but the frequencies in the upper bass and lower treble will be boosted as well. so it would
sound different than what you want.
 
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Your home audio system don't have the same acoustic like your car system, maybe your car loudness won't sound good in your home system.
If you insist on your car loudness, than if you have schematics you can copy that to your home amplifier.
 
Hi Prescot,

A properly arranged loudness compensation is volume-dependent.
The lower the volume - the higher the effect.

A couple of articles on the topic:
The Mysterious Loudness Control: What Does It Do? | Extron
OE Interface | musicarnw.com

Some modern car systems, as well as some home systems, have it implemented based on DSP - volume control and loudness compensation are fully digital then.

If you have some analog loudness compensation implementation in your integrated amplifier - we need to know the model and/or schematic / service manual to be able to comment.

Hope this helps.

Cheers,
Valery
 
Hi Prescot,

A properly arranged loudness compensation is volume-dependent.
The lower the volume - the higher the effect.

A couple of articles on the topic:
The Mysterious Loudness Control: What Does It Do? | Extron
OE Interface | musicarnw.com

Some modern car systems, as well as some home systems, have it implemented based on DSP - volume control and loudness compensation are fully digital then.

If you have some analog loudness compensation implementation in your integrated amplifier - we need to know the model and/or schematic / service manual to be able to comment.

Hope this helps.

Cheers,
Valery

My integrated amplifier is SAE TWO R9. And my car head unit is Nakamichi MTD-1. Both of them are old-school analogues. 😀

IMHO, it might be better to perform from the easiest to the hardest way; try adjusting the tone controls to duplicate the sound, before modifying the hardwares.

However, Schematics of both models are here.

SAE R9: https://filetools3.pdf24.org/client...554b30_6828536364706708877.pdf&action=getFile

Nakamichi MTD-1: https://filetools0.pdf24.org/client...ff243f_6393707486915068868.pdf&action=getFile
 
I'd like to update the progress to anyone who has the same problem with me. Now, I've found the sweet spot. I adjusted the tone controls to the half of loudness value: Bass = +4dB; Treble = +3dB. I'm happy with this trial and error method. Still, I'm wondering about the precise calculation. Could anyone help?