Need volume control design recommend.

[Jamebonds1]

Need good tone control design recommend for amplifier with preamp.

Hello everyone, I'm get together to building a amplifier with max 200 watt each channel for pre amp. For start before using amplifier, i want to building tone control first but I'm having trouble to decide for good controller schematic. I will also have basic calibration to prevent from blow up speaker on max volume which I can add on my own.

I'm looking for schematic that can control bass, treble and volume. Any idea design? I has like if schematic can be active control if possible.

 

[rayma]

I'm looking for schematic that can control bass, treble and volume.
Any idea design? I has like if schematic can be active control if possible.

http://www.ti.com/lit/an/sloa042/sloa042.pdf

 

[Jamebonds1]

That look nice. Thank you!

 

[rayma]

That look nice. Thank you!

You can use many modern op amps with this circuit, but they should be unity gain stable.

 

[Jamebonds1]

You can use many modern op amps with this circuit, but they should be unity gain stable.

Oh yes. It is possible. I have Creative ZrX with opamp.

There is opamp that I wanted but expensive was analog device. Are they good?

 

[forr]

I would first have a look at the Douglas Self's version of the Baxandall's active volume control using linear pots. I made my first try some months ago, I immediately adopted it, I felt stupid not to have done it sooner, knowing the schematic for twenty five years.

 

[AndrewT]

http://www.ti.com/lit/an/sloa042/sloa042.pdf

This is the first time I have noticed distortion results for the three conditions, flat, full boost and full cut.
In my view they are terrible. Flat shows 400 to 500ppm distortion plus noise over the full frequency range.
That may be why so many back in the 70s and 80s recommended that we bypass or forego any tone controls.
The last time I had any tone control was an amp I bought in the mid/late 70s (Sony ta something). I bypassed the tone controls soon after I got it and have never used any since, having moved to passive pre + Crimson Power Amp before the end of that decade.

 

[Jamebonds1]

I would first have a look at the Douglas Self's version of the Baxandall's active volume control using linear pots. I made my first try some months ago, I immediately adopted it, I felt stupid not to have done it sooner, knowing the schematic for twenty five years.

You mean this?
https://goo.gl/images/RJrr0X

This is the first time I have noticed distortion results for the three conditions, flat, full boost and full cut.
In my view they are terrible. Flat shows 400 to 500ppm distortion plus noise over the full frequency range.
That may be why so many back in the 70s and 80s recommended that we bypass or forego any tone controls.
The last time I had any tone control was an amp I bought in the mid/late 70s (Sony ta something). I bypassed the tone controls soon after I got it and have never used any since, having moved to passive pre + Crimson Power Amp before the end of that decade.

Where you get crimson power? I'm curious.

 

[AndrewT]

Try asking BePowell if they are still available.
The last I have are the mkVIII fully complementary.

 

[Pingrs]

In my view they are terrible...

I measured around -90dB at 1kHz (my sig. gen. limit) for my D.Self '96 pre-amp. Not so bad? Although Doug limits the boost/cut to 10dB.

Brian.

 

[chrismercurio]

Hi,

Have you read this thread?

http://www.diyaudio.com/forums/analog-line-level/194119-high-end-tone-control.html

While tone controls are very common on guitar amplifiers and on studio gear it's been relatively rare in home hifi for a very long time now. The title of the thread is misleading as it specifies volume control, but seemingly you are looking for a bit more than that.

I went looking for a Cello Palette schematic for you or a good explanation of Baxandall tone circuits and stumbled on the above. I hope it helps. I will say as far as volume controls go that I prefer transformer and autoformer based volume controls to stepped resistor and variable potentiometers.

Best of luck,

Chris

 

[forr]

You mean this?
https://goo.gl/images/RJrr0X

No.
A volume control à la Baxandall/Self :

See also :

NEGATIVE-FEEDBACK TONE-CONTROL: Oct 1952 Peter J Baxandall
The Wireless World Archive

Get the most out of your pot - Don?t mess up the rotation! - Precision Hub - Blogs - TI E2E Community

 

[Jamebonds1]

Hi,

Have you read this thread?

http://www.diyaudio.com/forums/analog-line-level/194119-high-end-tone-control.html

While tone controls are very common on guitar amplifiers and on studio gear it's been relatively rare in home hifi for a very long time now. The title of the thread is misleading as it specifies volume control, but seemingly you are looking for a bit more than that.

I went looking for a Cello Palette schematic for you or a good explanation of Baxandall tone circuits and stumbled on the above. I hope it helps. I will say as far as volume controls go that I prefer transformer and autoformer based volume controls to stepped resistor and variable potentiometers.

Best of luck,

Chris

Goodness gracious! You are correct. My bad. Yes, I'm into more like tone control, not volume control. I have seem some Autoformer are used in guitar amplifier; however, I need something for my 7 channel amplifier project that will be used with Onkyo PreAmp. In my search for building tone control and more op amp are appear. Are they good too?

 

[chrismercurio]

Okay. Well, please take a look at the thread I referenced in my post. Lots of good information regarding what you want.