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Ok so: Bought a sweet old Knight Model 333 stereo with a beautiful old walnut Cabinet built around it. Got some nice old Lincoln speakers in it too.

Here is my issue: something is wrong with the Right Channel. I am not incredibly electronically savvy, so I'm just going to explain things. So sorry if it's long-winded, or I use misnomers. Answers would be FANTASTIC.
Pictures of the back of the amp and the channel config diagram are included below, as well as a picture of the four speaker wire terminals (the four screws). I'm going to call each terminal intuitively: Top left/right, bottom left/right.

How it was set up when I got it was with the left speaker positive attached to the top left, negative to bottom left. Right speaker positive to top right, negative to bottom right. The left speaker worked, but the right did not, until I discovered that it would work when you changed one thing: crossing the left speaker's negative wire to the bottom left, where the right speaker negative was located.

So. I drank a beer. I thought. And I looked at the diagram, and realized everything seemed to be wired wrong. The diagram seemed to say that both positives were on the left side, and both negatives were on the right side. So I reconfigured it like that. Left speaker on top, right speaker on bottom. Left speaker worked, but the right still did not function, even when the negative was crossed to the top right, where the negative for the left was.

So what's up? I could definitely just cross the channels, but who knows if I'm gonna melt this old amp in the process? I love this thing, and would love to restore it to it's former glory. Thanks for any help.
 

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Ok so: Bought a sweet old Knight Model 333 stereo with a beautiful old walnut Cabinet built around it. Got some nice old Lincoln speakers in it too.

Here is my issue: something is wrong with the Right Channel. I am not incredibly electronically savvy, so I'm just going to explain things. So sorry if it's long-winded, or I use misnomers. Answers would be FANTASTIC.
Pictures of the back of the amp and the channel config diagram are included below, as well as a picture of the four speaker wire terminals (the four screws). I'm going to call each terminal intuitively: Top left/right, bottom left/right.

How it was set up when I got it was with the left speaker positive attached to the top left, negative to bottom left. Right speaker positive to top right, negative to bottom right. The left speaker worked, but the right did not, until I discovered that it would work when you changed one thing: crossing the left speaker's negative wire to the bottom left, where the right speaker negative was located.

So. I drank a beer. I thought. And I looked at the diagram, and realized everything seemed to be wired wrong. The diagram seemed to say that both positives were on the left side, and both negatives were on the right side. So I reconfigured it like that. Left speaker on top, right speaker on bottom. Left speaker worked, but the right still did not function, even when the negative was crossed to the top right, where the negative for the left was.

So what's up? I could definitely just cross the channels, but who knows if I'm gonna melt this old amp in the process? I love this thing, and would love to restore it to it's former glory. Thanks for any help.
Look at the diagram again- the + is next to both of the terminals on the left and the - is next to both of the other terminals. The diagram shows that the upper Left terminal is for the Left speaker, the bottom Left is for the Right speaker and the others are for the negative connections.

The upper pair go to the Left speaker and the lower ones go to the Right speaker.

Don't turn the power on or off when there's nothing connected to the speaker terminals and don't mess with the speaker connections when it's on- output transformers don't like that.
 

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How it was set up when I got it was with the left speaker positive attached to the top left, negative to bottom left. Right speaker positive to top right, negative to bottom right. The left speaker worked, but the right did not, until I discovered that it would work when you changed one thing: crossing the left speaker's negative wire to the bottom left, where the right speaker negative was located.
That does not quite make sense to me... But, it sounds like the right channel of the amplifier is out. I think when you had left speaker across positive terminals then took one of the right speaker leads to the left side you had the left amplifier driving both speakers. When you wired it correctly per the diagram you verified that the right channel is out (dead, malfunctioning, soundless, incapable of satisfying your musical needs, etc.)
 

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Discussion Starter #4
Solved!

Dead pre-amp vacuum tube was the issue. I found by switching two of the tubes, one of which had a dead indicator light, that I could move the problem from the left speakers to the right. I agree though Don, the wiring is really confusing, but the diagram seems to say that everything is wired horizontally, so when I wired it vertically I must have wired one side positive to positive. Thank goodness that somehow didn't blow anything up.
 
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