This resistor is very simple. It will have
stereo RCA in and out, and 1/8" mini
in and out.

All it will do is attenuate 2.5khz by 3
dB, with a Q wide enough to modestly
affect frequencies from 1kHz up to 4kHz.

Essentially to mildly scoop out those
audio frequencies humans most readily
hear. One could plug a line source or
phone into it, and RCA out, IE, to a
stereo amp. One could use the built-
in tone controls('Bass', 'Treble'), to
tailor the ends of the bandwidth to
taste.

Result? A smoother, less intrusive
sound at background or concert-
hall levels.

What materials do I need?

On 2016-05-29, wrote:
This resistor is very simple. It will have
stereo RCA in and out, and 1/8" mini
in and out.

All it will do is attenuate 2.5khz by 3
dB, with a Q wide enough to modestly
affect frequencies from 1kHz up to 4kHz.

Essentially to mildly scoop out those
audio frequencies humans most readily
hear. One could plug a line source or
phone into it, and RCA out, IE, to a
stereo amp. One could use the built-
in tone controls('Bass', 'Treble'), to
tailor the ends of the bandwidth to
taste.

Result? A smoother, less intrusive
sound at background or concert-
hall levels.

What materials do I need?

So not a resistor, but a filter,
a notch or band stop filter to be
precise.
You will at least need resistors and capacitors,
possibly one or two coils.

https://en.wikipedia.org/wiki/Band-stop_filter
http://www.radio-electronics.com/info/circuits/rc_notch_filter/twin_t_notch_filter.php
http://www.hobby-circuits.com/circuits/audio/audio-filter/590/rc-notch-filter-twin-t
http://www.instructables.com/id/Passive-Filter-Circuits/

Making it a passive circuit will also
attenuate the signal level, so you
might need some active amplification
in it to recover that.

http://www.circuitsstream.com/2013/06/simple-notch-filter-uses-operational.html
http://www.radio-electronics.com/info/circuits/opamp_notch_filter/opamp_notch_filter.php

In article ,
says...

This resistor is very simple. It will have
stereo RCA in and out, and 1/8" mini
in and out.

All it will do is attenuate 2.5khz by 3
dB, with a Q wide enough to modestly
affect frequencies from 1kHz up to 4kHz.

Essentially to mildly scoop out those
audio frequencies humans most readily
hear. One could plug a line source or
phone into it, and RCA out, IE, to a
stereo amp. One could use the built-
in tone controls('Bass', 'Treble'), to
tailor the ends of the bandwidth to
taste.

Result? A smoother, less intrusive
sound at background or concert-
hall levels.

What materials do I need?

a Graphic EQ.

Jamie

On Monday, May 30, 2016 at 8:30:43 AM UTC-7, M Philbrook wrote:

a Graphic EQ.

Jamie
....which you can find on eBay, many under US$20 (and even cheaper at a ham swap).

On Sun, 29 May 2016 11:43:05 -0700 (PDT), wrote:


Result? A smoother, less intrusive
sound at background or concert-
hall levels.


Smoother than what?

Twin-T, RC filter.

Black Iccy wrote: "Smoother than what?"


https://upload.wikimedia.org/wikiped...indos1.svg.png

Read up on it.

wrote in message
...

This resistor is very simple. It will have
stereo RCA in and out, and 1/8" mini
in and out.

All it will do is attenuate 2.5khz by 3
dB, with a Q wide enough to modestly
affect frequencies from 1kHz up to 4kHz.

Essentially to mildly scoop out those
audio frequencies humans most readily
hear. One could plug a line source or
phone into it, and RCA out, IE, to a
stereo amp. One could use the built-
in tone controls('Bass', 'Treble'), to
tailor the ends of the bandwidth to
taste.

Result? A smoother, less intrusive
sound at background or concert-
hall levels.

What materials do I need?






You want a parametric EQ you can build yourself.

Good luck with that.


Gareth.

On Mon, 30 May 2016 16:23:22 -0700 (PDT), wrote:

Black Iccy wrote: "Smoother than what?"


https://upload.wikimedia.org/wikiped...indos1.svg.png

Read up on it.

No use pointing me at a set of Fletcher-Munson curves.
I met those more than 60 years ago so if you think they're
a point of enlightenment for me. Wrong. Particularly wrong
because those curves are statistical averages for particular
known levels. If you're trying to produce a response contour,
those curves are not *it*. Turn up the volume a bit and your
ears will respond differently.

If you're trying to attenuate the mid-range audible levels
for yourself, then you're intensifying the effect. Possibly wrong.

If you think that a source has not had sufficient attention
by the recording engineer at the time and that he/she did
not endeavour to ensure a good result (one which you don't like)
so you alter the response that's for you to decide. The easiest
way is to build *nothing* and just raise the trevble and bass
controls a fraction - same result.

On Tuesday, May 31, 2016 at 3:00:18 AM UTC-4, Black Iccy wrote:
On Mon, 30 May 2016 16:23:22 -0700 (PDT)
Black Iccy wrote: "Smoother than what?"


https://upload.wikimedia.org/wikiped...indos1.svg.png

Read up on it.

No use pointing me at a set of Fletcher-Munson curves.
I met those more than 60 years ago so if you think they're
a point of enlightenment for me. Wrong. Particularly wrong
because those curves are statistical averages for particular
known levels. If you're trying to produce a response contour,
those curves are not *it*. Turn up the volume a bit and your
ears will respond differently.

If you're trying to attenuate the mid-range audible levels
for yourself, then you're intensifying the effect. Possibly wrong.

If you think that a source has not had sufficient attention
by the recording engineer at the time and that he/she did
not endeavour to ensure a good result (one which you don't like)
so you alter the response that's for you to decide. The easiest
way is to build *nothing* and just raise the trevble and bass
controls a fraction - same result.
________________

The point is, doing so sounds good to
me. There are two audible "muddy zones"
in the audio spectrum, to either side
of 1kHZ: between 150-250Hz, and between
2-4kHz. A low-Q modest scoop(2-3dB) in
those areas cleans things right up,
whether I'm listening through full-size
speakers, headphones, even if I'm
listening through those dreaded Apple
Buds that ship with every iPod.


All I need is a filter for at least the
higher "mud"(2-4khz) that can fit inline
between my iPod and the receiver or
amp it's connected to, or inline between
the CD player and same amp. I have a
15band graphic EQ in my listening system,
but need something a *little* less clunky
for mobile purposes. A filter, if one can
be built that's a little bigger than a
Zippo lighter, would do the trick.


By modestly reducing those areas, I don't
need to "raise the treble and bass". Plus
I've already bought some gain by said
reduction. And even though I looked at
the graph, the area of upper mid-range
I need to reduce that sounds good to
me is slightly lower, between 1-3kHz.
As you said, the published curves represent
averages, so they may not work for
everyone.

On Tue, 31 May 2016 04:45:10 -0700 (PDT), wrote:
The point is, doing so sounds good to
me. There are two audible "muddy zones"
in the audio spectrum, to either side
of 1kHZ: between 150-250Hz, and between
2-4kHz. A low-Q modest scoop(2-3dB) in
those areas cleans things right up,
whether I'm listening through full-size
speakers, headphones, even if I'm
listening through those dreaded Apple
Buds that ship with every iPod.


Oh I know exactly what you're trying to achieve.
"In the old days" there were two main approaches.
(1) Tone controls with variable 'knee' frequencies.
(2) Variable 'effectiveness' loudness compensation.
Twin-T passive filter would be best for your case,
cheapest and easiest to build anyway.