Blue LED light not turning ON

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SKY888

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Joined
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Hello,

I bought a nice used pair of Theos online.

They’re both working fine, but one of the Theos doesn’t turn on its blue led light. I tried switching the low volt cables, but no luck.

I know it’s ON since I can here that slight buzz from the panel, when I turn up the gain of my external amplifier.

Is this an easy fix?
Or there’s some deeper issues I need to worry about since the blue LED light is not turning on?


Or just let it be?

Thank you
 
Hola Sky888,

I do not understand when you say external amp. There is no built in power amp into your Theos. Inside the speaker cabinet, you will find a lot of electronics, and no power amp there.

If you have an issue with the power supply unit into the Theos, the stat panels will not produce a sound. There are two possible things that could make your blue LED not lite. 1) you have a bad blue LED. 2) There is a problem with the circuit that detects the signal and turns on the blue LED. If this is the case, my recommendation is to contact Martin Logan Service Dept. and explain to them your problem. They will track better to find the culprit. If you have having both speakers sounding almos identical, to me, it is not too important. Just a blue LED not working. But I could be WRONG!. It is better to contact ML.

Happy listening!
 
Hi Roberto,

Yes, the Theos don’t have internal amplifiers.

I run my theos using my crown amplifier (external amp).

Both the theos have sound on the panel, and sounding perfectly.

But one theos don’t have blue LED light when running. Only the other theos has blue led light.

I’m hoping that during shipping, it damaged the led bulb.

I’m not sure if there are any internal or underlying issues that will occur soon such as issues with internal bias power supply board?

Or as long as the panel is producing good sound, I don’t have to worry about the internal power supply board.....since it might just a bad led bulb?
 
Yes, I think that you are safe. The LED (Light Emitting Diode) its a semiconductor. You can have a bad connection or a faulty diode. You can ask to the ML service dept if you are safe using it them that way.

Happy listening!
 
Hi,

I had a similar problem with one of my Montis speakers in that the blue LED with the Martin Logan insignia didn't light. The speakers continued to work fine.

I contacted ML and they sent me a replacement LED very promptly. I was able to swap out the bad LED no problem.

It required removing some screws with Allen head sockets which was a bit difficult because the screws are painted making the Allen Key difficult to insert. But it
ended up fine.

The service person at ML was excellent, btw.
 
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