Volume potentiometer

**yaniv** · 08-06-2008, 08:08 PM

Hi,
I want to create a simple analog volume knob for my carputer. Right now I'm connecting the computer directly to the amplifier but I want to put a potentiometer in-between them so I can easily adjust the volume. It will basically be connected to the RCAs coming from the computer and into the audio-in in the amp.

I don't want to buy an equalizer since I don't need one and don't have any room to put it in.

Do you know if I can use this thing for this idea? Do you know what th 'K' stands for?
http://cgi.ebay.com/ALPS-732t-50KBX4...742.m153.l1262

Thank you very much!

**netstat** · 08-06-2008, 08:45 PM

i don't know what the k stands for, but i think you want something a little simpler.

this would be more for repairing a home theater head unit where the knob "turns itself" when you adjust the volume from the remote control like some of the higher end Sony's and Pioneers did. Thats where the motorized part comes in, would be pretty complicated to utilize that in your car setup.

**pcpete** · 08-06-2008, 08:52 PM

Im using JL Audio CL-RLC line driver/remote volume. They work perfect for me, google it and see if it's what you're looking for.

PS.. I use one to control volume gains to sub amp , and another to control gain to my tweeters. (active front stage).

**barnyard** · 08-06-2008, 09:00 PM

I picked up one from http://www.davidnavone.com/ a while back, but I can't seem to locate it on his site now.... It works great!

**hailrazer** · 08-06-2008, 10:29 PM

Originally Posted by barnyard

I picked up one from http://www.davidnavone.com/ a while back, but I can't seem to locate it on his site now.... It works great!

http://www.davidnavone.com/cart.asp?14&pid=129

**FPeter** · 08-06-2008, 10:50 PM

why dont you use sw control? its much simplier, and there is no risk for noise! you can find several knob option, like this, and others...

**scott_fx** · 08-07-2008, 01:20 AM

Originally Posted by yaniv

Hi,
I want to create a simple analog volume knob for my carputer. Right now I'm connecting the computer directly to the amplifier but I want to put a potentiometer in-between them so I can easily adjust the volume. It will basically be connected to the RCAs coming from the computer and into the audio-in in the amp.

I don't want to buy an equalizer since I don't need one and don't have any room to put it in.

Do you know if I can use this thing for this idea? Do you know what th 'K' stands for?
http://cgi.ebay.com/ALPS-732t-50KBX4...742.m153.l1262

Thank you very much!

k stands for thousand... 50k as in the amount of resistance

the thing that sucks about going with a passive pot is that you have to run your audio cables to the pot then to the amp. if your pc is in the trunk then thats a lot of wiring. if your pc is near the dash then your ok... if not i'd look into a digital pot that takes the pot out of the signal and will allow you to remotely mount it without addind long rca cable runs

**yaniv** · 08-07-2008, 05:30 AM

Software control is not usable for me since the computer must first turn on for me to use it. If the audio is already too loud I'd have to blow my ears and only then lower the volume. Also, I already have that in my frontend so I don't need another one.

About the JL Audio CL-RLC, it's very expensive considering all it does it control volume. I can get an equalizer roughly at the same price. Also it's only 2 channel and I'm looking for a 4 channel solution.

The motorized part of the potentiometer is useless for me but I'm not going to use it anyway. These should be turnable by hand as well.

I did consider I will have to to transfer some more wires in the car. There are a lot of them already so a couple more won't be a problem

I am mainly concerned about the OHM values for these resistors. What would be enough for lowering a car amp's volume from MAX to ZERO?

**FPeter** · 08-07-2008, 06:47 AM

Originally Posted by yaniv

I did consider I will have to to transfer some more wires in the car. There are a lot of them already so a couple more won't be a problem

and you will win noise, noise, and some more noise

the MAX5440 IC is your best friend! only a gray code rotary encoder required with push function. you can ignore the LED-line and MODE button part of it (if balance function is not required). just connect the push button to MUTE, and the encoder's CHA, CHB. its an half-analog stuff, so the long wires might cause noise. an ADuM1400 or ISO7240 is recommended to fully isolate the button's long wires from the mixer IC...

im working now on a similar project: i have a crap opel factory headunit. its good to fill the huge hole, and has a big rotary encoder knob on its front. i will connect this to a microcontroller, decode the gray code to simple up/down signals, then connect it to my usb soundcard's vol up/down/mute buttons...

**yaniv** · 08-07-2008, 07:09 AM

Originally Posted by FPeter

the MAX5440 IC is your best friend! only a gray code rotary encoder required with push function.

I don't have much knowledge in electronics. I don't even know where to get this stuff.

Wouldn't it be exactly the same thing as having an analog volume control? I will still have to connect this to an analog wire no? Or are you talking about windows volume control (as I stated I don't want this).