Simple tone control?

Mon Nov 21, 2011 4:53 am   

I'd like to add a simple op amp-based tone control circuit to my preamp for
desktop speakers & sub that I'm modifying from stock.

This is the simplest I found:

<http://www.simplecircuitdiagram.com/2010/02/03/single-op-amp-tone-control/>

(I have +/- supplies so I will be eliminating all coupling caps and changing
Vcc/2 to ground.)

What are the positives and negatives to this design?

Better circuit (yet simple)?

Thanks.

Mon Nov 21, 2011 5:17 am   

"DaveC"

** Too many crossposts by far.



** The TLC2272 IC specified has max +/- 5 volt supplies.




.... Phil

Mon Nov 21, 2011 5:24 am   

I guess I'll have to find another amp with wider V spec.

Thanks!

Mon Nov 21, 2011 1:03 pm   

This looks a lot like the kind of tone controls mass-market
consumer-electronics equipment has been using for the past 60 years.

I don't know /exactly/ what your plans are, but the 1kHz corner frequency is
about the worst possible if you're trying to correct errors in the speakers
you're designing.

Unless you want a "tone control" that produces shrill treble and boomy bass,
you need to move the treble corner up, and the bass down.

Furthermore, it would make sense to design the speakers first, and see what
sort of correction they need. There are plenty of inexpensive drivers with
relatively flat response (if you believe the spec sheets). Neither they nor
most recordings will need much in the way of correction, so the best tone
control would be one that supplies small amounts of boost and cut at the
frequency extremes.

Unless you're looking for lots of boom and sizzle.

There are plenty of op-amps with a wider voltage range -- the 5534 and
TL-074 come to mind, but these are rather old designs. I'm sure someone will
be able to recommend something newer.

Mon Nov 21, 2011 1:08 pm   

"William Sommerwanker "


** Every single notion expressed by this congenital wanker is wrong.

In each case, the opposite is true.


..... Phil

Mon Nov 21, 2011 2:17 pm   

"Phil Allison" <phil_a_at_tpg.com.au> wrote in message
news:9iut9lFgl3U1_at_mid.individual.net...


When Mr Allison deigns to speak courteously, he is almost always a fount of
useful wisdom. (Seriously.)

But he is completely wrong. I have given good advice. Ignore it at your own
peril.

Mon Nov 21, 2011 10:17 pm   

On Nov 21, 3:53 am, DaveC <inva...@invalid.net> wrote:

It would really help to explain what you mean by that. 6" drivers in
wood cabs plus a 12" sub? Or 2.5" pc speakers plus a 4" sub? Very
different animals.



As said, the odds are the freq response wont match what you want. A 5
band graphic equaliser would be better, and is pretty aesy to make.


If you wanted simplest, the circuit can be far simpler if you use the
existing amp's nfb path to simply insert treble & bass boost controls.

Bass boost: Pot and C in parallel in the nfb path,
Treble boost: Pot and C in series from nfb path to ground, after a
resistor.


NT

Mon Nov 21, 2011 11:36 pm   

<
http://www.harmankardon.com/EN-
US/Products/Pages/ProductDetails.aspx?PID=SOUNDSTICKS3AM>

The video is pure marketing.

I don't have these speakers, but I do have the original SoundSticks I which
are USB input devices (no analog input). I've converted them to analog input.

Looking for an op-amp-based filter circuit. Anybody have a favorite you can
link to? Or put up an ASCII or Spice diagram?

Thanks.

Tue Nov 22, 2011 12:50 am   

"William Sommerwanker = Fuckwit Jerkoff "


** So totally proven to be the RIGHT kind for domestic audio.



** Tone control are mostly used to alter the frequency balance of the
program material.

That is why they have knobs on the front panel......




** The type of circuit shown has variable bass corner frequency and variable
slope treble.



** False assumption that they need any or that it is the main issue.



** Shame about deficiencies in the program itself.




** Or have program lacking in both lows and highs - like many u-tube vids.



** Both those are wrong for the job, the OP need a dual op-amp - so an
NE5532 or a TL072.

Both these are still the most widely used audio op-amps in the world.




** Only an audiophool wanker would.

And look who did.


..... Phil

Tue Nov 22, 2011 3:04 am   

Phil, learn something about audio.

Tue Nov 22, 2011 3:09 am   

On Nov 21, 10:36 pm, DaveC <inva...@invalid.net> wrote:

nothing there

Tue Nov 22, 2011 3:14 am   

"William Sommerwanker = LYING PIG "




** ROTFL !!

What an absurd irony.



.... Phil

Tue Nov 22, 2011 6:05 am   

http://www.harmankardon.com/EN-
US/Products/Pages/ProductDetails.aspx?PID=SOUNDSTICKS3AM


Yes there is. Maybe you have to copy & paste the URL, but it is valid.

Tue Nov 22, 2011 6:31 am   

"DaveC"


http://www.harmankardon.com/EN-US/Products/Pages/ProductDetails.aspx?PID=SOUNDSTICKS3AM




** The link leads to a home page and nothing else.



.... Phil

Tue Nov 22, 2011 6:47 am   

NT wrote...



I think the HK site redirects if it doesn't think you are in the US.

UK version here
http://uk.harmankardon.com/harman-kardon-product-detail-uk/soundsticks-
iii.html

Recommended by the News Of the World:-)

--
Ken O'Meara
http://www.btinternet.com/~unsteadyken/