Hi all, I have recently acquired a Pass Labs X2.5 Preamp and X150.5 power amp, both just 5 years old. I'm not having much luck with either I'm afraid.
The pre developed this cracking/popping sound accompanied by this 'electronic rushing wind sound' in the right channel. I'll start a new thread on this shortly. It's been at my tech for the last week and he's not found the cause yet.
Secondary to that, the power amp thumps/pops when powered on. About as loud as conversation level and the current meter swings up over half way when it does it from cold. However if you turn it off then back on relatively quickly (I don't do this habitually of course, I was just testing), say within a second of powering it off, it thumps hard enough to feel it in your chest from 60cm from the drivers (what I'd call loud) and the current meter swings up to 3/4 or so across the dial.
Whether or not the amp has the preamp connected, if the XLR shorting pins are in place there is only a barely audible noise at power up or down, the loud thump only occurs with the XLR shorting pins in place (with or without the preamp connected).
The preamp is currently a mystery, but the power amp popping sound - is it normal and if not, what's causing it?
The pre developed this cracking/popping sound accompanied by this 'electronic rushing wind sound' in the right channel. I'll start a new thread on this shortly. It's been at my tech for the last week and he's not found the cause yet.
Secondary to that, the power amp thumps/pops when powered on. About as loud as conversation level and the current meter swings up over half way when it does it from cold. However if you turn it off then back on relatively quickly (I don't do this habitually of course, I was just testing), say within a second of powering it off, it thumps hard enough to feel it in your chest from 60cm from the drivers (what I'd call loud) and the current meter swings up to 3/4 or so across the dial.
Whether or not the amp has the preamp connected, if the XLR shorting pins are in place there is only a barely audible noise at power up or down, the loud thump only occurs with the XLR shorting pins in place (with or without the preamp connected).
The preamp is currently a mystery, but the power amp popping sound - is it normal and if not, what's causing it?
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They can be a little hit and miss with emails, but they're moving right now so I guess it's a bad time.
edit - just to clarify that, I asked say 2 questions and they answered 1. I asked it again worded more clearly and there was no response so I just let it go. I guess I was just putting it out there in case the community had encountered these issues I'm experiencing before.
edit - just to clarify that, I asked say 2 questions and they answered 1. I asked it again worded more clearly and there was no response so I just let it go. I guess I was just putting it out there in case the community had encountered these issues I'm experiencing before.
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I would have the technician swap the left and right channel modules. He
might have to tweak the offset and bias, but it should help localize the fault.
😎
might have to tweak the offset and bias, but it should help localize the fault.
😎
Kent suggested that via email (swapping the UGS modules - this is the preamp I'm talking about here) but nothing has triggered the sound again since he's had it.
I've not spoken about the power amp with the tech yet, figured I'll try and get the preamp fixed first then find out what's going on with the power amp.
I've not spoken about the power amp with the tech yet, figured I'll try and get the preamp fixed first then find out what's going on with the power amp.
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