Fvllt*ne Deja'Vibe MDV-2 Hiss

[Stratomaster]

Hello all,

It's been a while.  I picked up a MDV-2 on craigslist mostly because it was a steal of a price.  However, much to my dismay, I plugged it in and noticed a persistent hiss.  I've tried multiple power supplies as psu issues with charge pumped vibe clones has been a well-documented problem (one I've had in the past and discussed w/ RG Keen at length w/ a Neovibe build).  The problem still persists and is way noisier than my Neovibe build.

I noticed that the hiss is constant with the intensity knob down, varries with the volume knob (louder at higher outputs), and seems to be slight affected in time with the phasing when the intensity is dialed back up.  To me this tells me that the problem is not in the LFO driver, or the output section but rather either the input or one of the phase stages.  So I'm asking, do you all have any ideas as to what would be causing this hiss? Alternatively--what other parts besides the bulb-driver transistors have you experienced fail over time?

Side note: Noise aside, my Neovibe with some of RG's and JC's mods incorporated smoke this thing. I should never have bought it.

[Scruffie]

I'd probably start with an audio probe tracing through to see if you can find a source of hiss in the audio path, see the debugging page.

[strassercaster]

Hello all,

It's been a while.  I picked up a MDV-2 on craigslist mostly because it was a steal of a price.  However, much to my dismay, I plugged it in and noticed a persistent hiss.  I've tried multiple power supplies as psu issues with charge pumped vibe clones has been a well-documented problem (one I've had in the past and discussed w/ RG Keen at length w/ a Neovibe build).  The problem still persists and is way noisier than my Neovibe build.

I noticed that the hiss is constant with the intensity knob down, varries with the volume knob (louder at higher outputs), and seems to be slight affected in time with the phasing when the intensity is dialed back up.  To me this tells me that the problem is not in the LFO driver, or the output section but rather either the input or one of the phase stages.  So I'm asking, do you all have any ideas as to what would be causing this hiss? Alternatively--what other parts besides the bulb-driver transistors have you experienced fail over time?
Sorry to hear you have problems . You will figure it out.. I have built 2 univibes a harbinger one on pcb and one on stripboard. Luckily i havent had this problem. What mods did you do to your neovibe ?
Side note: Noise aside, my Neovibe with some of RG's and JC's mods incorporated smoke this thing. I should never have bought it.

[hibust]

Hello,
I just assemble the pedal Univibe Harbinger One and I have the same problem as you. A persistent whistling swing changes by rotating the speed potentiometer. Did you find the solution?
Thank you