Dual Ganged Stereo Volume Control

[gjpwiz]

Hello,

I have a 2.1 speaker system with a RCA/analog Stereo input. This is connected to my TV which has a fixed audio output only, so I cannot control the volume using the TV remote. I have a RCA extension from the TV's output to the speaker input and am planning to add a volume control on this extension wire.

Browsing thru the forum I saw a suggestion to use a "100K Dual-Ganged Stereo Volume Control" 100K Dual-Ganged Stereo Volume Control - RadioShack.com However I noticed the input impedance of my speaker is 4ohms (Z623 Technical Specifications - Logitech FAQ). Will this control work with my speaker system? If not, could someone suggest an alternative? Thanks!

 

[KMossman]

I would venture to say that you really need an active 'amp';


TV-----> > voltage follower, volume control, voltage follower ---> > speaker system

voltage follower could be a single-ended op-amp, dual ps op-amp, or a tansistor[or fet or ...]

 

[KMossman]

I have a RCA extension from the TV's output to the speaker input and am planning to add a volume control on this extension wire.

You need a special pot for that. radio shack used to carry...........

 

[gmphadte]

It would be good if u buy a second hand stereo with a working remote control. We can better advice from there on.

One of the simpler option is to rewire your TV audio out after the volume control, may it be any type.

Gajanan Phadte

 

[DUG]

L-pad

The Madisound Speaker Store

 

[sofaspud]

Active speakers with a 4Ω input impedance??

I think the Radio Shack product that KMossman mentioned is this one, catalog #42-2559. I'm pretty sure most stores still stock it. I've bought a few. Not the greatest item but it gets the job done.
If it were me I think I would just tap the remote-controlled volume with a resistor or transformer.

 

[KMossman]

Active speakers with a 4Ω input impedance??

maybe not very active? 😱

 

[sofaspud]

or maybe they've discovered the secret to "straight wire with gain."

 

[KMossman]

L-pad

if some-one outside the audiophile sphere hears you are looking for an L-pad it will surely raise some eyebrows..................

 

[gjpwiz]

I went ahead and connected a stereo potentiometer and it controls the volume quite well. The only issue is that there is a small hum/buzzing noise when the knob is not at the maximum position. Any inputs on how to reduce this?

 

[gmphadte]

Use shielded cable. Do not connect shield on both the ends.

Gajanan Phadte

 

[hukkfinn]

if some-one outside the audiophile sphere hears you are looking for an L-pad it will surely raise some eyebrows..................

Just curious, why would that raise eyebrows?

 

[KMossman]

Use shielded cable. Do not connect shield on both the ends.

Gajanan Phadte

Ground on the target/sink/receiving side?

 

[DUG]

if some-one outside the audiophile sphere hears you are looking for an L-pad it will surely raise some eyebrows..................

🙂