Midrange attenuation of 4-5dB needed

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My single driver speaker has a 4-5 dB boost centered around 1kHz. I would like a tone control to provide a gradual dip centered at the 1kHz to offset the "frowny face" FR that I now have.

Perhaps just use the midrange tone control on this design?
TC3 Three Band Tone Control Equalizer DIY Kit Bass Mid Range Treble Stereo | eBay

I do not need a volume pot as I do not need variable, just a fixed 4-5dB, attenuation.

Could someone here suggest something with better sound quality? Could someone here build this midrange tone control for a fee?
 

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Yes, I did read it. I just didn't believe it was a full description. :)

You can have different slopes towards a centre frequency (which will decide on what order of filter you need), different flatness at the top, and peaks are very rarely symmetrical. Also, it is in the nature of minimum phase things (including speakers) for a peak to be almost invariably accompanied by a corresponding dip. The complexity of the problem may therefore go beyond what a basic filter such as the one shown can achieve.

If you think that the tone control here happens to meet your needs, and it does seem to centre on or close to 1kHz, then $68 would be a pretty cheap way of achieving it. It would even be worth it to find out what part of what you need it does do. Sometimes, some of these eBay offerings give some of the cheapest R&D that can be found.
 
If you think that the tone control here happens to meet your needs,

If you read my original post you would see that no, it does not:

1) I do not need treble and bass boost.
2) I do not need variable attenuation - i.e. pot

You can have different slopes towards a centre frequency (which will decide on what order of filter you need),
The most efficacious range would be 500-1,500 Hz but the F-R varied so much around the room that those exact numbers are not set in stone. The average between the high and low is, as you can see, 1,000Hz.

That's why I posted here. Those on Ebay have pretty distorted sound. So much so, that in many cases I'd rather live with the uneven F-R. If that Ebay tone control met my needs I would not have posted.

Do you have a midrange tone control in mind? One that would minimize phase shifts and all that other stuff that the usual "specs" fail to define? HD, etc. does not say much as to final sound quality IME. I have used Behringer, Parasound, and Denon UDM-31. For some strange reason only the cheap Denon m-s did not audibly distort the sound. So if you know of a design like the Denon, that would be ideal.

Have a great weekend!
 
If you read my original post you would see that no, it does not:

1) I do not need treble and bass boost.
2) I do not need variable attenuation - i.e. pot


The most efficacious range would be 500-1,500 Hz but the F-R varied so much around the room that those exact numbers are not set in stone. The average between the high and low is, as you can see, 1,000Hz.

That's why I posted here. Those on Ebay have pretty distorted sound. So much so, that in many cases I'd rather live with the uneven F-R. If that Ebay tone control met my needs I would not have posted.

Do you have a midrange tone control in mind? One that would minimize phase shifts and all that other stuff that the usual "specs" fail to define? HD, etc. does not say much as to final sound quality IME. I have used Behringer, Parasound, and Denon UDM-31. For some strange reason only the cheap Denon m-s did not audibly distort the sound. So if you know of a design like the Denon, that would be ideal.

Have a great weekend!


I can't think why the eBay ones should be distorted. There's not much to them and you could change the op amps anyway.

Did I have a control in mind?

No. I would have designed it from scratch. Unfortunately you appear to be too rude to make that an enjoyable prospect.

Have a great weekend, Chuck.
 
cod3gen, thanks for the link but I don't know, they write:
" Phase shifts tend to be a little more radical, and the passband has more ripple than a conventional circuit, but only where a number of sliders are set to boost or cut. "

I don't need sliders or individual frequency adjustment.

No. I would have designed it from scratch. Unfortunately you appear to be too rude to make that an enjoyable prospect.

ChristianThomas, people like you are easy to figure out. No surprises there.

1) Ask a bunch of impressive sounding questions.
2) Tease me that you could do something.
3) Then throw out insults at me as an excuse not to.

Enjoy yourself!
 
What your wanting is probably best done at the speaker end of things, but that would be more expensive with the need for inductors. My best recommendation is a simple buffered notch filter. This gives around -6db at 1kHz and -3db at 500Hz and 1.5kHz. I can't make any promises on sound quality and the like so it's up to you.
 

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Since the line level tone controls provides so much audible distortion, I thought I would try one after the power amp. Like a regular crossover component. I got this info from Parts Express but they could only design for -9db. From my testing with equalizers, I know -9dB is much too high.
Does anyone here know what value I use to cut the center attenuation down to -4 to -5 dB? Here is what they gave me:

The low -3 dB frequency would be
600 Hz, the center frequency at 900 Hz, and the upper -3 dB
frequency at 1200 Hz. The amount of attenuation at the
center should be about 9 dB.

Capacitor: 33 uF (027-350)
Inductor: .8 mh (255-044)
Resistor: 2.4-ohms (004-2.4)

They are all twisted in parallel and connected to the plus speaker terminal.
 
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