Instructables

[Answered] Balance Control Not Working Properly?

Okay, I bought an older karaoke system, which I am using as a speaker for my iPod and an amp for my guitar.  As you have probably deducted from that, it has RCA stereo auxiliary inputs and 2 mic inputs.  I plug my iPod into the RCA aux in jacks, and it is sending out a stereo signal.  The cable I use is a special cable originally intended for an audio/video cable for my camera.  It's wiring scheme allows me to use it as a 3.5 mm (1/8 in) male audio plug to the two stereo, RCA male plugs.  I press play on my iPod, and of course music comes out.  The "amp" has a balance pot on it (pot meaning knob).  When the balance pot is centered, the left channel is full volume, but the right channel is weak.  To get the full right channel, I have to turn the pot all the way right, which of course blocks the left channel out.  There is a "sweet spot" around the 4 o clock position that evens out the channels, but they aren't as strong.

KaydenST (author) 2 years ago
Well, I solved the problem! It turned out that the contact on another control (the 3.3 kHz EQ slider) is dirty, and is affecting the channel output. I have determined this by randomly messing with controls. All I had to do was press on the 3.3 kHz EQ slider. I will get that cleaned.
lemonie2 years ago
Was it cheap, and did you know about the fault before you bought it?
Amps sometimes fail on a channel like this - it's broken.

L
KaydenST (author)  lemonie2 years ago
I don't know how much it was originally. I bought it second hand for $5 at a yard sale. I can't find anything about this specific model, The Singing Machine Recording Studio SMW-63, on the internet, except for a reference to it on radio shack's website. The page is text only so I am guessing it is old. I didn't know about the fault before I bought it. Just remember as I stated above, it's technically a karaoke system. Oh, and it all of a sudden worked last night, but then it didn't work like 20 sec later... Weird... My uncle said to try some sort of spray you can but that is supposed to clean the contacts on the pot.
Well, you might try replacing things like cap's and the pot'?

L
KaydenST (author)  lemonie2 years ago
That is what Steve is saying below. I might try to open it up for a look inside...
KaydenST (author)  KaydenST2 years ago
Well, I opened it and looked inside. I didn't see anything like bulging capacitors or anything, and the balance pot looks okay, but again I can't tell just by looking at it.
I'll suspect the balance control is damaged. Open the unit and you will find two potentiometers "wired" together mechanically. You can buy new ones.

Steve
KaydenST (author)  steveastrouk2 years ago
So you would open it up, find the potentiometers, buy new ones, and solder them on?
Yep,