Variable Loudness DIY for Noob?

Or lower, depending on the kind of music, and it can also be the mastering level, if someone has been adjusting the bass during mastering.

When I still used a loudness control, I just put the reference level on whatever seemed to sound about right for that recording. I don't see the point in using pink noise and a sound pressure level meter to carefully adjust it to a completely arbitrary level.
 
https://www.radioshack.com/products/radioshack-100k-dual-ganged-stereo-volume-control

It looks like these are still available. I have a few (from when RS was still a real company) and they're pretty good.
The website says "sold out". That was a very good pot, made by ALPS and somehow ended up at Radio Shack. ;)

This won't help the OP, but I find that I don't need loudness compensation. The bigger problem is that pop/rock music nearly always has tipped-up treble to make it "radio-friendly". As a result, this music cannot be played loudly on a neutral system.
Ed
 
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Believe me. 95% of all loudness circuits don't work. Probably because people don't know what it's about, even Yamaha has some circuits in their devices that work poorly. It's a tough subject. The circuit in https://www.rfcafe.com/references/e...s-control-electronics-world-december-1963.htm isn't bad, but it's also pointless because the pot offers no signal offness.
I was planning to build that very circuit and still am. It will need a buffer before and after. I don't quite catch why a separate sub control is needed though. The lower frequencies are automatically covered, It is easy to simply bypass the loudness with an DPDT.
I owned a Yamaha receiver in the late 70s that featured the circuit I am trying to recreate. At that time you set a reference volume level and had the loudness correction at minimum. Thereafter you left the volume alone and used the loudness to control the "volume".
 
They're made by Alps, pretty decent pots. They used to be $1.98.
Metric, and a too-long shaft, though.

I wish I would have bought more when I had the chance. RS closing caught me by surprise.

I live by Northwestern University in Evanston. The RS by the campus was the best. It was always busy with the electronic components flying off the shelves, unlike other RS stores that specialized in junk and cellphones. The clerks were college kids that were interested in electronics, unlike other RS stores that employed rude and annoying cell phone pushers.

Don't get me wrong. RS deserved to die a painful death. I just needed one last shopping spree.
 
In China a taobao store called Lu-ge (osprey song) has a huge selection including about a half-dozen loudness circuits. Some are based on Sharp GF-777. I have one and it sweetened the trebble (as some speaker XO did) without noticeably losing transparency. The passive version with defeat switch may lose too much gain if there's no preamp.
 

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Typical listening level. "Ideal" level for faithful reproduction is original performance SPL, which is quite often higher than 86 dB.
If I’m playing back a recording on monitors, I want to play it back at the decibel level it was mixed at, preferably in a room with similar dimensions, acoustic treatments and the same monitors. Often we listen much quieter than this, hence, the loudness control. At louder levels than 86dB, all bets are off - which is the case anyway with a standard volume control (except for one position).

I did research and enough recordings that I enjoy were mastered in facilities using the 86dB standard so I am satisfied with that as a target.
 
There was a german diy-shop, http://www.thel-audioworld.de/ who claimed he had the loudness-control module.
It looks like mr. Thel has retired, and the folks running the shop don’t offer it anymore. But I haven’t investigated the matter ans so I don’t know the present situation there. Maybe, with luck and charme…
Here the associated - no longer exist website from 2003:
https://web.archive.org/web/20030627234814/http://www.thel-audioworld.de/bauteile/regler/Potis.htm
There is to read follow:
==================================================================

Die neue Poti-Generation in der Medium-Klasse.
Endlich gibt es ein hochwertiges Poti, auch für Mehrkanal-Anwendungen, das in Bezug auf Klangqualität ein unschlagbares Preis/Leistungsverhältnis bietet.
Lieferbar als 1- 2- oder 6-Kanal-Poti.
Wird ein 4- oder 5-Kanal benötigt, schließt man einfach nur 4 Kanäle des 6-fach-Potis an. Der Widerstandswert 6x20kOhm/logarithmisch kann so gut wie in allen 10kOhm/log Anwendungen eingesetzt werden. Ebenso in den meisten 50kOhm/log Anwendungen. Alle THEL-Potis mit Mittenanzapfung.

The new poti generation in the medium class.

Now there is a high-quality potentiometer, even for multi-channel applications, that offers best price/performance ratio in terms of sound quality. Available as 1, 2 or 6 channel potentiometers. If a 4 or 5 channel is required, simply connect 4 channels of the 6-way potentiometer. The resistance value 6x20kOhm/logarithmic can be used in almost all 10kOhm/log applications. Likewise in most 50kOhm/log applications. All THEL pots with center tap.

==========================================================================


I want to know the manufacturer of this potentiometer - it isn't Alps. Maybe still available from other suppliers.

P.S.: dead URL in post #19 - here the currently URL:
https://vajacases46-com.myshopify.com/products/radioshack-100k-dual-ganged-stereo-volume-control
 
 

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(Following all this because I am also quite interested in a good loudness-solution…)
Remembering my teenage time when a friend brought me to his friend's place, whose father had the big Klipschs with all McIntosh. I asked if I could touch. Grabbing the knob that said "Aural", I rotated it to the right for increasing effect. Ohhh, Baby - the way Linda Ronstadt sing it.

It's a pretty simple circuit and unsure of it would have the same effect today. Perhaps the rest of the system had something to do with it ;')
 
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