CoolCat
Well-known member
I grabbed this used ART MPAII. $200...Guitar Center 45 day return.
PLugged it in and noise and waterfall hsssssssing and so popped in two tubes and it seemed to be working.
But then I noticed it needs to be left on a little bit, 30 seconds or more. Then it seemed to have another problem and this was traced to
the Gain knobs and if thwacked a little bit connected or dislodged the dust and worked fine.
but then I noticed both Tube Warmth LED meters were reacting to my one channel Mic IN sounds.
So Googled a bit using AI and it was very responsive and offered good basics like spray DETOX and press the STEREO/ DUAL button a bunch.
Then it went further into powering down plugging and unplugging all connectors and most things a basic tech would do.
But then I kept adding this didn't work, this did, and working on it I noticed the Channel Bleed suspect was not really an issue if the channel not being used gain was at zero.
Still the Tube Warmth LED was showing both moving and lit, with only one microphone in one channel.
This AI led to mentioning the probable DIODE faulty and explained the Tube Warmth display functionality...which is way beyond the manual or any podcast.
It also explained the rails and shared Vacuum tube could be leaking, and an issue. Which is all FREE info and seems to be right on the mark.
The Tube Warmth LED meter is supposed to reference each channel's Gain increase to each Tube separa=tly, for each seperate channel.
But this units faulty.
Basically there's a cheap looking LED display with a cheap board and a small ribbon cable that plugs into the motherboard and somewhere the "bleed" is happening.
Per the REAPER tracks there's no bleed on the actual Outputs, but turning each output to 0 helps...
So anyway, AI seems to have come a long way and goes deeper than I expected.
As for a Used ART MPAII.....
1. Tubes bad...
2. Gain pots need thwacked at times...
3. TubeWarmth LED display has a cross feed issue....
I've had two or three ART MPA and Voice Channels and even the rare REFERENCE series, and VU meters and they are $200 range units. Pretty good for HR use.
My ISA430 has some LED issues too in display only, the Digital out works fine.....Never had a ISA One issue, never had a JoeMeek issue.... had some Aphex issues 107, and 207 insert jack..
So not knocking the ART MPA really, even the used Grace M101 I recently had needed some detox, and LA610 unit had scratchy pots and was 8x's more expensive.
Heres a sample of the troubleshooting by AI....prerty impressive really,
PLugged it in and noise and waterfall hsssssssing and so popped in two tubes and it seemed to be working.
But then I noticed it needs to be left on a little bit, 30 seconds or more. Then it seemed to have another problem and this was traced to
the Gain knobs and if thwacked a little bit connected or dislodged the dust and worked fine.
but then I noticed both Tube Warmth LED meters were reacting to my one channel Mic IN sounds.
So Googled a bit using AI and it was very responsive and offered good basics like spray DETOX and press the STEREO/ DUAL button a bunch.
Then it went further into powering down plugging and unplugging all connectors and most things a basic tech would do.
But then I kept adding this didn't work, this did, and working on it I noticed the Channel Bleed suspect was not really an issue if the channel not being used gain was at zero.
Still the Tube Warmth LED was showing both moving and lit, with only one microphone in one channel.
This AI led to mentioning the probable DIODE faulty and explained the Tube Warmth display functionality...which is way beyond the manual or any podcast.
It also explained the rails and shared Vacuum tube could be leaking, and an issue. Which is all FREE info and seems to be right on the mark.
The Tube Warmth LED meter is supposed to reference each channel's Gain increase to each Tube separa=tly, for each seperate channel.
But this units faulty.
Basically there's a cheap looking LED display with a cheap board and a small ribbon cable that plugs into the motherboard and somewhere the "bleed" is happening.
Per the REAPER tracks there's no bleed on the actual Outputs, but turning each output to 0 helps...
So anyway, AI seems to have come a long way and goes deeper than I expected.
As for a Used ART MPAII.....
1. Tubes bad...
2. Gain pots need thwacked at times...
3. TubeWarmth LED display has a cross feed issue....
I've had two or three ART MPA and Voice Channels and even the rare REFERENCE series, and VU meters and they are $200 range units. Pretty good for HR use.
My ISA430 has some LED issues too in display only, the Digital out works fine.....Never had a ISA One issue, never had a JoeMeek issue.... had some Aphex issues 107, and 207 insert jack..
So not knocking the ART MPA really, even the used Grace M101 I recently had needed some detox, and LA610 unit had scratchy pots and was 8x's more expensive.
Heres a sample of the troubleshooting by AI....prerty impressive really,
