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PA+ No input displayed, no output

msinklairmsinklair Posts: 7
edited May 2016 in PA General Discussion
I purchased my PA+ 2 years ago used. I have been an extremely happy user since, until last night.

2 days ago I was going through presets and fine tuning stuff. I power cycled my gear twice before the end of the night. Everything was working properly. Yesterday I had some time to switch my processing gear to a larger rack. After getting everything mounted and wired, I have no input display on the dB meters, as well as no output display and sound.

My first thought was I did something wrong when I moved everything. So, I started systematically troubleshooting.
The test gear involved:
Pioneer CDJ-1000 to a Pioneer DJM-600. Pink noise is played with the average signal at 0dB on both the channel and main faders.
+4dB balanced XLR out to the PA+, from there it's balanced XLR to two Mackie SRM-450's.
Bypassing the PA+ by connecting the in and out XLR cables results in pink noise from the Mackie's.
So, all of the other gear is tested and working.

Powering up the PA+ shows normal boot tests. All of the LED's do their blink and the display is proper. I then reconnected everything.
The preset for the Mackie's that worked 2 days ago automatically loaded. Bringing up the signal showed no change in the PA+ LED meters. With the level going in I should have seen limit lights as well as signal, and the limiter should have been kicking in.

I tried reloading the preset, no change.
I tried different presets, no change.
I did a soft reset, no change.
I did a factory reset, no change.
I reloaded the latest firmware (which I had installed when I first purchased the untie), no change.
I am able to move around all the menus, change settings, and the RTA works as well.
I opened the unit up thinking maybe something came loose. Nothing was loose or banging around.
Reseated the cables just in case, no change.

I'm hoping someone can point out something I have overlooked before I have to send this in for service.

Thank you for your time,

Max

Comments

  • DraDra Posts: 3,844
    Let's check things off.
    Not a fuse, because it powers up.
    Not limiting or compressing, because those LEDs are not igniting.
    There are no mute buttons on the inputs. The inputs would light, even if the outputs were muted.

    Did you eliminate cables for your by-pass test or did you link them? You should have connected all cables used.
    Try the +4/-10 button on the PA+ in both positions.
    Try the Auto EQ function, to see if the PA+ is passing it's own pink noise. According to the flow diagram, the pink noise circuit is in the input section. Be sure to check the input meters to see if they function, whether you have output or not.

    DRA
  • Dra wrote:
    Did you eliminate cables for your by-pass test or did you link them? You should have connected all cables used.

    Yes, all of the same cabling was used. I disconnected the PA+ and connected the cables directly together.
    Dra wrote:
    Try the +4/-10 button on the PA+ in both positions.

    I did that as well as the ground lift.
    Dra wrote:
    Try the Auto EQ function, to see if the PA+ is passing it's own pink noise. According to the flow diagram, the pink noise circuit is in the input section. Be sure to check the input meters to see if they function, whether you have output or not.

    The input meter shows room noise from the RTA mic. (My talking, coughing, etc)
    The output meter shows Left High going up as I raise the level with the encoder. No sound comes out of the Mackie. I verified that I had connected to the Left and Right High as I was using the DualPassive preset with no modifications. So, sound should have been produced.
  • DraDra Posts: 3,844
    The RTA input is a monitor only. It can't pass sound to the outputs.

    Try the auto eq to see if pink noise excites the inputs and outputs. If so, verify that the noise gets to the speakers.

    DRA
  • Dra wrote:
    The RTA input is a monitor only. It can't pass sound to the outputs.

    Try the auto eq to see if pink noise excites the inputs and outputs. If so, verify that the noise gets to the speakers.

    DRA
    msinklair wrote:
    The input meter shows room noise from the RTA mic. (My talking, coughing, etc)The output meter shows Left High going up as I raise the level with the encoder. No sound comes out of the Mackie. I verified that I had connected to the Left and Right High as I was using the DualPassive preset with no modifications. So, sound should have been produced.

    This was the result from the Auto EQ. No audio was passed out of the PA+ The input meter I reference is the LED dB meter. It shows reaction from the RTA Mic input during the Auto EQ test. The Left High LED dB meter shows signal when raising the level, but no sound is produced.

    I'm sorry for the delayed responses. I though that by subscribing to the thread, I would get an email notification. I'll try to check more frequently.
  • DraDra Posts: 3,844
    I have not been getting notices for a while now.

    I want to be very clear here. Do this.
    Set up a new program.
    2 x 2 (stereo, EQ - stereo linked, full range - custom - passive, no subs, select custom amp).
    Connect a speaker to each high output.
    Set the speakers' inputs to 10 o'clock.

    Press AEQ button. If required, plug into the RTA input.
    Turn up the pink noise level until you hear it in both speakers.
    Unplug or turn off the speakers.
    Continue turning up the pink noise.
    Are the Input meters lighting?
    Are the Output meters lighting?
    Can you get them to fully light up, matched in and out?

    If yes, end the pink noise.
    Plug your DJ rig into the PA+ inputs.

    What now? Meters? Sound?
  • Dra wrote:
    I have not been getting notices for a while now.

    I want to be very clear here. Do this.
    Set up a new program.
    2 x 2 (stereo, EQ - stereo linked, full range - custom - passive, no subs, select custom amp).
    Connect a speaker to each high output.
    Set the speakers' inputs to 10 o'clock.

    Press AEQ button. If required, plug into the RTA input.
    Turn up the pink noise level until you hear it in both speakers.
    Unplug or turn off the speakers.
    Continue turning up the pink noise.
    Are the Input meters lighting?
    Are the Output meters lighting?
    Can you get them to fully light up, matched in and out?

    If yes, end the pink noise.
    Plug your DJ rig into the PA+ inputs.

    What now? Meters? Sound?

    New program entered as instructed.
    I used the wizard in advanced mode and when it ended it was in Auto-Level mode.
    Speakers set at 12 o'clock since this is there normal +4dB input setting.
    Turning the level al the way up to clip shows full LED output on the high display.
    No sound comes out of the speakers.
    With no RTA mic plugged in, nothing on the input LED meter.
    With the RTA mic plugged in, ambient room noise shows on the input.

    After exiting the Auto-EQ, and then playing a sound source from my mixer, there is no sound or input/output displayed.
  • DraDra Posts: 3,844
    Well that settles it. It's broke. Call tech support. Sounds like a repair or replace.

    DRA
  • Dra wrote:
    Well that settles it. It's broke. Call tech support. Sounds like a repair or replace.

    DRA

    Boo
    Okay, thats what I initially figured. I'll give them a call while I price a second one or maybe a 260.

    Thank you for your time.
  • msinklairmsinklair Posts: 7
    Just to follow up with a result.

    I sent it in for repair. It was a very fast turnaround. They had billed my card a day after they received the PA+. I then received it back a couple days later.

    It had a shorted DA chip. They also replaced two power supply cap's per a service bulletin.

    I wonder if the cap replacement was to absorb power on surges.
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