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Fender Passport 250

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  • Fender Passport 250

    This unit is acting weird. Customer complains of intermittent cutting out. I'm trying to figure the damn thing out. I've read the manual and nothing in there alludes to the weirdness I'm finding. The dual/stereo mode switch is an oddity. In any case it's not cutting out on me currently and I've been running some music into the stereo inputs, bypassing the preamp. I have it in stereo mode and when both master volumes are at 12 o'clock the audio sounds thin... as if the channels are out of phase. If I turn one master down the sound gets more normal. Also if I turn the left or right master down, there is good sound but still in both speakers. Whereas I'd expect only one speaker to be putting out sound. ?? Anyone have experience w/ these?

  • #2
    Repaired one a few months ago (schems are around here somewhere).
    They are rather cheaply made, and alot of areas could be intermittant.
    Once you get it apart (not an easy chore) check all the connectors, cables, reflow any pots, jacks and switches that may be suspect.

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    • #3
      Customer brings it and says "cutting out." What does that mean? It is a stereo amp. DO both speakers go silent? At the same time? Or does just one speaker go silent? I have had speakers with a bad tweeter. From stage, it goes out, they can;t hear that side even tho0ugh the woofer still runs. They tell me it cuts out.

      What are they amplifying? One mic? FOur? If only one mic, did they try a different one? A bad mic or cord is the same thing as speakers cutting out to a novice. And if the mic is OK, did they try a different channel? If they always use channel 1 and IT is funky, the speakers cut out in their mind. Did you try channel 2? No, we always use channel 1. It was cutting out.

      In other words, don;t assume that their complaint means exactly what YOU would describe in their words.


      Out of phase speaker sound? MAybe it is out of phase. Did you use your speakers or theirs? Your speaker cables or theirs? Did you check their speakers for having same phase? Did you check their cords? They may have "repaired" a cord and got it back. Hell, from stage out of phase speakers can sound like sound going away.

      It is not very easy for an amp like that to all of a sudden reverse phase on one output.
      Education is what you're left with after you have forgotten what you have learned.

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      • #4
        Have you played with the VIP (voice input priority) Chan. 1? It's a ducker and will limit output on the other channels for a second or two... are the speakers plugged in right? In monitor mode left/main output will be mono right/monitor will come from aux sends on each channel - could account for things sounding weird... in normal mode it's stereo left and right. The other thing that was strange on this is the EQ controls. 12 o'clock is normal and only mids and highs are accentuated or attenuated... could any of these or any combination of be a source of cutting out or sounding thin?
        Last edited by captntasty; 05-16-2012, 03:50 AM.

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        • #5
          I have not gotten it to cut out. I've played music through it for hours. The only odd thing is that in STEREO mode when both LEFT and RIGHT masters are at 12 o'clock some of the audio goes away, as if the speakers are out of phase. The cables LOOK original and are molded connectors. I suppose a speaker could have been replaced but not sure so I will ask the guy. Again this is all going into the stereo RCA inputs so i'm not using the preamp channels. I should however check those to see if those are what's cutting out. I am trying to figure out how the MASTER controls and the different modes function so that I have a good handle on it before troubleshooting. Enzo I'm with you on all that. I always rediagnose symptoms myself AFTER hearing out the customer. That's why I haven't taken the thing apart yet.

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          • #6
            SO run a single signal into an input channel, forget stereo. Pan to center. Still phase-ish? In a case like this you can't pick one input and run it forever and know the amp is OK, you have to try the other inputs too. If chennal 3 was screwy and all we ever did was play CDs through the stereo jacks, who'd ever know there was a problem with channel 3?


            DOn't ask the guy if he changed a speaker, TEST the phasing yourself. Got a working stereo? COnnect his speakers to it. They don;t have to be pushed at all to hear phasing. Or just plug a cord into each cab and do the battery te4st. DO both cabs move the same direction with the battery?
            Education is what you're left with after you have forgotten what you have learned.

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            • #7
              you must be a night owl like me. good call on all that. will do tomorrow. this still leaves me confused as to why it sounds as such when going into the stereo ins... but alas maybe your tests will reveal something.

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              • #8
                Whenever I see a Passport with the symptom "cutting out", I'm reminded of this: http://music-electronics-forum.com/t24273/
                The short form version of the post I pointed to is: Found a speaker cable that came with a Passport system to have a barrel nearly 2mm longer than it should have been. Inserting it fully caused the output of that channel to be shorted, and to cut in/out. I know you haven't actually seen this problem yet, but maybe you aren't plugging in the cables the way the customer does.

                As for your phase issues: Are you only using the stereo inputs? I have seen issues on a stereo headphone output where the sound turns into a vocal cancellation type of thing when the common ground opens up. Not sure it would do the same on an input, just thought I would mention it.

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                • #9
                  guy doesn't wanna pay to fix it... understandably. speakers seem to be in phase when going into the channels inputs. definitely a preamp issue as the channels are cutting out. Oh well we'll never know.

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