Digital Tone Control, and Audio Switches

"lighthouseman"

** This code scribblng fool is a blinking idiot.

** ROTFL !!

That is a totally analog IC, from 1987, intended for car radios !!!

** Ever hear of DSP ??

... Phil

Just because a device is old, doesn't make it useless. DSP is a bit much for a simple tone control don't you think?

Since you seem to be 'up' on these things, which DSP would you suggest then (since that would have answered the original question, instead of just mocking).

No I didn't, if you would read the orginal post you'll see that I asked for a line level stereo tone control which was able to be controlled by a microcontroller - ie a digitally controlled tone control.

On a sunny day (Fri, 5 Jun 2009 03:06:33 -0700 (PDT)) it happened lighthouseman wrote in :

Do not let Phil distract you.... The DSP solution is possible, but DSP always has some latency. say delay, between in - and output, that can be probelmatic in some applications. Also you need a 16 analog inputs and outputs, not simpel either.

IIRC there are I2C controlled tone control chips from Philips, but been too long ago to remember any numbers. Else you could google. Here is one I found with google: TDA7440D

It also has input selection, so could perhaps be used to do part of the 8 x 8 selector you mention.

Maxim parts may be difficult to get. Perhaps the 74HC4051 8 to 1, you'd need 16 of those.... plus opamps to drive those and for the outputs. There exists a chip that has all of that integrated, it was quite expensive IIRC.

"lighthouseman"

** This pommy loon really is a LIVE ONE .

All I was looking for was a suggestion for a tone control IC, which could be digitally controlled ...

** Then go find one - if you think they really exist.

So, to add a simple tone control to an existing embedded amp design, you think I should add ADC, DSP and DAC, rather than a simple tone control IC ?

** What IC is that then ?????

Is that really the only way to do it?

** Nowadays - yes.

It is the only way being commercially implemented.

..... Phil

"Jan Panteltje"

** I think these two f****it LOONS are just made for each other.

So I'll sit back and just watch their romance blossom.

.... Phil

On a sunny day (Fri, 5 Jun 2009 21:24:48 +1000) it happened "Phil Allison" wrote in :

Am I imagining this, or is Philo getting worse lately?

y,

Ah, Phil - you've made my day. Just as I was beginning to think that the world was sane again, you come along and re-assur me that it is as insane as ever. For example, I'm glad to see politicians are getting back to what they are used to - fleecing the tax payer and getting caught with their hands in the cookie jar.

Normality (but not sanity) has been restored.

As for the others, thanks for the genuinely helpful replies.

LHM

National Semiconductor Audio Subsystems.

Bob

tourettes?

-- Bill Naylor

Electronic Kits for Education and Fun

Well, it is not so weird not to choose DSPs. A while ago I talked with someone (an expert when it comes to building audio mixers) about building a fully digital mixer. The problem is that current DSP based mixers don't sound right. I assume this has something to do with phase distortion caused by digital filter algorithms that can execute fast but have a lousy phase characteristic.

--
Failure does not prove something is impossible, failure simply
indicates you are not using the right tools...
                     "If it doesn\'t fit, use a bigger hammer!"
--------------------------------------------------------------

On a sunny day (Fri, 5 Jun 2009 21:04:16 +0100) it happened "Electronworks.co.uk" wrote in :

From

Coprolalia (the spontaneous utterance of socially objectionable or taboo words or phrases) is the most publicized symptom of Tourette's, but it is not required for a diagnosis of Tourette's and only about 10% of Tourette's patients exhibit coprolalia.[15] Echolalia (repeating the words of others) and palilalia (repeating one's own words) occur in a minority of cases,[8] while the most common initial motor and vocal tics are, respectively, eye blinking and throat clearing.

Seems there is no treatment :-(

"Nico the Fuckwit Coesel"

** Strewth - now we have audiophool logic draged in. ** That is all you ever do, you stinking wog f*****ad.

.... Phil

What about using some of those cheap "digital resistor" things that everybody makes (ADI, LTC, TI) in a couple of simple RC circuits?

John

's

) ]

But you don't write in a Tourette manner, but rather only speak that way. Writing is not "spontaneous."

Is Phil ever on his meds?

Assuming the tone controls are single pole, that would probably work.

And thanks for keeping it G-Rated.

On a sunny day (Fri, 5 Jun 2009 18:48:15 -0700 (PDT)) it happened " snipped-for-privacy@sushi.com" wrote in :

OK, maybe he uses a speech to text engine :-)

Lost for an answer there.

Yip I did say that in my original post. Thanks for the link - very helpful.

So, I already have a nice 20W + 20W Class D amp with a single stereo line level input. What I'm trying to do is add the ability to select between 8 different stereo pairs, and add tone control. The amp has NO user controls, already has a built in microcontroller with an ethernet interface

My original idea, as you know, was some anaolog switch for the input selection, and Tone Control by some (mythical?) IC. It seems that is not going to be easy, so maybe I need to look at DSP as Phil rather eloquently suggests.

So now I'm looking for some suggestions for audio processors, which will let me do gain and EQ (or vol/treble/bass/[balance]) or any other valid suggestions.

What would you do?