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  • April 18, 2022 at 6:05 am #190229
    Mr.Pickadilly
    Participant

    Hey I’m experiencing signal bleed on both inputs of my 45000 looper.

    Even with the input pots set to 0 my SSS Fat 50(low gain) Strat signal can be heard on the output.
    I am using the correct power supply.
    The result of this issue is that I have a higher noise floor and no true isolation between left and right input channels.

    Another issue I’m experiencing that may or may not be related to this fail mode is that the playback volume of my loops are significantly louder than the signal I’m monitoring at.
    All faders are set to the max as well as the headphone pot (I’m using the monitor output), Input Pan pot turned to the left.
    This means that as soon as I loop a track my input signal is being drowned out by the loop.

    Does anyone know what might be causing these issues or how to solve them? If they are the result of a bad pot/s or something similarly simple I would be happy to purchase replacement parts and do the repair myself.

    This machine has brought me a lot of joy over the years and I hope to keep using it for years to come but at the moment it just doesn’t cut the mustard.

    Thanks for the continually innovative and awesome products EHX!

    Aidan

    April 18, 2022 at 9:54 am #190230
    EHX STAFF
    Keymaster

    Please standby the head engineer will be back tomorrow to answer.

    April 19, 2022 at 3:04 pm #190237
    Flick (EHX Staff)
    Moderator

    Where do you have the pan pot just above the DRY OUT slider set to? Ensure this pan pot is set to the full counterclockwise LEFT position so that Left Input is only heard at the Left Output and Right Input is heard only at the Right Output.

    You might have to bring down the four track sliders a bit for a better balance between the dry signal and the recorded tracks.

    April 19, 2022 at 4:17 pm #190241
    Mr.Pickadilly
    Participant

    Sorry, I should have been more clear; Dry pot is fully counter clockwise and I am still hearing both inputs.
    I’ll reiterate that this happens even when input gain knobs are also fully counter clockwise. I obviously don’t know how the circuit works but it’s as if the signal is never fully shorted to ground.

    I had considered turning the faders of the tracks down but as I understand it, each initial loop I record on the same track will essentially start to fade out as I layer on top of it; this doesn’t seem right.

    In other words; if I record bass notes and higher pitch lines on the same track, for instance, the second line recorded will always be louder with this solution. Each new loop becomes the loudest as the older loops multiply by a lesser number and “fade out”.

    Are there quick voltages/resistances I can check to confirm a failure?

    Thanks Flick,
    Aidan

    April 25, 2022 at 1:55 pm #190255
    Mr.Pickadilly
    Participant

    Hoping to get an update on this as my issues remain unresolved.

    I attempted setting my track faders lower to achieve unity gain but had to set them half way from the top causing any per track overdubbing to essentially replace the track recorded prior.

    Again, pan pot above dry input fader is fully CCW.
    Dry Fader is also set to 100%.
    Looped phrases appear to be boosted or dry/direct monitoring is attenuated.

    Still dealing with bleed across both inputs.

    In the past I have been sent a replacement pot by EHX for a faulty headphone pot that was causing another set of similar issues; the replacement solved those issues.

    I wonder if these issues sound related to faulty pots or perhaps a cold solder?

    Cheers,
    Aidan

    April 26, 2022 at 12:48 pm #190257
    Flick (EHX Staff)
    Moderator

    Sorry I didn’t see your responses sooner.

    You might have a bad DRY Pan pot. If the DRY OUT slider is at max, does turning the DRY pan pot change anything about the output signal? Make sure you have some signal going through the unit when testing this.

    You’re right that moving the track faders below zero will cause the audio on the tracks to fade-out when overdubbing, so you do want to keep the track faders at maximum. Possibly we’ll get some DRY level back after figuring what’s going on with the DRY bleed.

    April 26, 2022 at 3:47 pm #190258
    Mr.Pickadilly
    Participant

    Hey Flick, no worries, thanks for following up!

    I ran a signal through my Left Input set the Dry Fader to full and plugged headphones into the Headphone Out. When I turned the pan pot from Left to Right it sounded pretty normal; when fully turned CCW sound came through Left earphone, turning towards 12 O’clock I got signal through both earphones and finally tuning fully CW I got signal through the Right earphone.

    Using the Right Input instead and doing the same test I got the expected opposite signal routing: CCW went to Right, 12 O’clock to both, CW to Left.

    Both sweeps were smooth.

    Though there is bleed from either Input only the respective Input Pot will change the gain on that signal, in other words; if I plug a signal into the Left Input only the Left Input Pot affects the signal gain, Right Input Pot has no affect on gain. The opposite is also true.

    Still, with each Input Pot set fully CCW signal passes through to the Output stage of the device.
    While this bleed occurs the Dry Pot works as expected panning/blending/reversing stereo.

    I just tried using the Left & Right Outputs respectively and got significantly less bleed but also less gain when adjusting the Input Pot.

    Unity gain between the Left & Right Output (individually) and the Headphone Output occur with the Headphone Out Pot set at 9 O’clock.

    In this context I’m using unity gain to refer to that of the Headphone Out and the Left/Right Mono Outputs , not of the signal actually coming in/out of the 45000.

    I’m sorry if this response comes across as patronizing or repetitive at times; it’s not my intention. I’m just trying to be as thorough as possible to avoid unnecessary back and forth!

    Thanks again Flick,
    Aidan

    April 26, 2022 at 3:56 pm #190259
    Flick (EHX Staff)
    Moderator

    Is the bleed problem you’re experiencing that you still hear sound coming through the inputs when their respective L or R INPUT knobs are set fully counterclockwise?

    If this is the case, this is normal. These pots are gain pots, not volume pots, they allow sound throughout their entire range.

    September 8, 2023 at 10:15 am #204435
    billcutbill
    Participant

    I’m having the exact same problem.

    In my scenario I am using Input 1 to record a vocal using a microphone. In Input 2 I am using an aux send from my desk to route synthesizers for looping.

    I turn the Input 1 to OFF, but given they are gain pots and not volume pots, the vocal is always heard when the dry out fader is up.

    This also means that with the Input 1 pot set fully OFF, it will also always be recorded, i.e. in mono mode it will record the synthesizer with a vocal bleed.

    I send the 45000 to a delay in my pedal chain, which I use quite hard, so I don’t want a bleed of vocal constantly coming from the pedal. I can use the Dry Out fader to turn off the dry signal, but this also turns off the signal from Input 2 so then I don’t have any synthesizers being routed through.

    This would be resolved if the gain pots were volume pots, and gave full control over the inputs. Could it be possible to mod this unit so that the Inputs do control the input fully and have the ability to turn the input off, rather than just controlling a bit of gain? I would be very interested in this modification if it is offered… I’m currently considering returning the pedal.

    It’s a very odd design – why would you add input knobs and have them not fully control the inputs?? Confusing.

    I have found a small workaround which is to run the 45000 in the stereo mode, but only use the left output jack. That way I can use the pan on the Dry Out which effectively becomes the volume control I need, so I can turn it off to not have it in the mix while Input 2 is. The negative of this is I can only run this pedal in mono plus I always have to record in stereo mode with the loop faders 1 and 3 turned down… so I only really get 2 channels of loop rather than 4… unless I want to loop vocal bleed.

    Any suggestions with my scenario would be appreciated. God I wish the input control knobs could actually fully control the inputs…

    September 8, 2023 at 10:40 am #204442
    Flick (EHX Staff)
    Moderator

    Sorry, yeah there’s isn’t a good way to mute one of the inputs unfortunately. Probably your best bet is to find a way to mute the microphone before it hits the 45000. Maybe even a microphone with a switch like the Shure SM58S.

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