Need help on audio analogvolume control circuit

[jordan76]

I am trying to learn about audio analgo volume control circuit design,but I cannot find useful stuff till now. Coudld any one help me? Thanks in advance!

regards,
jordan76

 

[machine]

I think you can find many projects and tatouriala regarding this subject .Cay yoo specify more for the info. you need ?

 

[12ax7]

What do you want to know?

things to bare in mind:
- It is usual to use a Logarithmic law pot control in audio
- You need to know impedance of subsequence stage fed from the pot
as too high a pot value can cause premature HF role off (treble loss)
- NEVER allow dc curent flow in pot (gets very noisy) only signal should flow.
- Best place to place control is a tradeoff between 'outputend' noise and frontend stage peak signal handling level in relation to input signal level.
- Use good quality pot for audio- ALPS pots are good for Hi-Fi
-
hope this helps a bit. Checkout Langford Smith ( Radiotron's Designers Handbook old but excellent)

 

[Longfuse]

If you want voltage control check out the National Semiconductor data sheet for the LM13700 OTA chip. It has basic templates for voltage controlled amplifiers.

 

[jordan76]

Many thanks,guys.

I must admit that I almost know nothing about audio analog volume control.
However, let me try to make it more specific.
Basically it is used for TV systems. For this application, I assume that the noise and THD should be very low; dynamic range should be very high; gain should be tunable.

Actually I want to know the usual specifications, architectures and design challenges etc.

regards,
jordan76