Archon 100 FX loop issue

[Aaron W]

I have a 2017 Archon 100/50 with an FX loop problem When it first arrived (used) the FX loop was noisy, adding a sound of rushing air along with the signal. Now it is completely killing the signal, along with an increased sound of rushing air through the speaker cabinet. The amp is otherwise perfectly noiseless when not using the FX loop. Is it possible that the tube is bad and is not allowing signal passage?
I have seen a few posts with some solutions for noise however, I have not seen a post dealing with complete signal loss.

 

[László]

I have a 2017 Archon 100/50 with an FX loop problem When it first arrived (used) the FX loop was noisy, adding a sound of rushing air along with the signal. Now it is completely killing the signal, along with an increased sound of rushing air through the speaker cabinet. The amp is otherwise perfectly noiseless when not using the FX loop. Is it possible that the tube is bad and is not allowing signal passage?
I have seen a few posts with some solutions for noise however, I have not seen a post dealing with complete signal loss.

The sound of air rushing through the speaker usually a preamp tube has started to fail. But it's hard to know until you try to diagnose the problem and try different tubes.

Mesa's manuals explain how to isolate a bad tube. The rules are the same for PRS amps. You can download their manuals on their website.