Pedals not playing nice together

Themoleman

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I am a big fan of inexpensive pedals and there are some great ones out there. Recently I purchased an M-vave mini universe (reverb) and an M-Vave Elemental (delay). They are both capable of some crazy sounds but refuse to play nice together. No matter where in the efx chain I put them, if they are both plugged in I get a tone, whine, whatever you want to call it. Not hum or buzz. The frequency is around 300 Hz.
D or D#. Any ideas what would cause this? I have not tried separate power supplies yet. Any suggestions would be helpful. Thanks
 
Yes it is a 10 unit isolated power supply. I only have 8 Efx pedals on it. So I did try putting the one box on it’s own power supply and the rest on the 10 outlet. No change. 300hz tone. There’s no way the manufacturer will respond, after all, it’s a $40 pedal. I just hoped that some else has had this issue or maybe a pedal designer might know.
 
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Yes it is a 10 unit isolated power supply. I only have 8 Efx pedals on it. So I did try putting the one box on it’s own power supply and the rest on the 10 outlet. No change. 300hz tone. There’s no way the manufacturer will respond, after all, it’s a $40 pedal. I just hoped that some else has had this issue or maybe a pedal designer might know.

Can you run either of them on batteries to see if that changes anything?
 
Hmm, odd it's happening with those. Does it occur over time, like the delays/reverbs stacking up end up creating a feedback loop, or is it an immediate thing when you turn both pedals on?
 
Sounds like that digital whine that you get from unisolated power in digital pedals....even though yours PS says it's isolated, it may be allowing something funky....... usually that clock noise comes back through the power .....from my experience.

I know you said you have an isolated supply, you should troubleshoot with 2 separate supplies, or as stated earlier, a battery if able.

Also, just for consideration, are the units getting appropriate milliamps? Is the supply maxed out with many digital , higher current pedals?

These are all major considerations.
 
fwiw 7 of the Amazon reviews of the Mini Universe mention a whining noise, even with isolated power supplies, etc. One review says the only way to fix it is to use the USB power ("However, the only way I got it to operated without a slight whine through the guitar amp was to use USB power").

Interestingly enough, the description of the pedal on Amazon says "Multiple power supply interfaces: Two power supply interfaces, USB Type C or DC 9V adapter (centre is negative),which are suitable for different scenarios. Please use the TYPE C port to power it first. It is recommended to use power bank for power supply,you will get wonderful sound. Or you can use your mobile phone charger for power supply and it requirs above 5V1A power adapter."

The USB thing might be worth a try, but it's also possible that some of the pedals are just faulty and perform this way since not everyone reports the problem. I'd try to exchange it if possible.
 
60 Cycle Hum mentioned a whine in his review (though much less prominent than you're describing), but in his case putting it on a one spot fixed it (33:30):



Though, again, some Amazon reviews mention this not working for them, so it may be that some are faulty in a way that isn't necessarily obvious without certain configurations or signal paths.

If you do try other power supplies: I didn't look for the manual and I didn't see more info on the Amazon listings, but one comment on that YouTube video say it needs at least 300mA ("The Mini Universe pedal needs to be on a 300ma isolated power supply.").

Another comment says that switching to a 500mA 9V power supply fixed the issue for them ("I recently got one of the mini universe pedal and I was getting the whine as well. Tried everything. effects loop, straight thru to input, different positions on board, valve amps compared to solid state... no matter what had the whine until I tried a different power supply. It's true what is written in the little pamphlet. This pedal is only happy with 9v 500 ma power.and whine be gone!")
 
60 Cycle Hum mentioned a whine in his review (though much less prominent than you're describing), but in his case putting it on a one spot fixed it (33:30):



Though, again, some Amazon reviews mention this not working for them, so it may be that some are faulty in a way that isn't necessarily obvious without certain configurations or signal paths.

If you do try other power supplies: I didn't look for the manual and I didn't see more info on the Amazon listings, but one comment on that YouTube video say it needs at least 300mA ("The Mini Universe pedal needs to be on a 300ma isolated power supply.").

Another comment says that switching to a 500mA 9V power supply fixed the issue for them ("I recently got one of the mini universe pedal and I was getting the whine as well. Tried everything. effects loop, straight thru to input, different positions on board, valve amps compared to solid state... no matter what had the whine until I tried a different power supply. It's true what is written in the little pamphlet. This pedal is only happy with 9v 500 ma power.and whine be gone!")

I absolutely love both pedals. I will certainly try 500 ma. Or I may just end up running one of them on a new pedal board I need a second board.
 
fwiw 7 of the Amazon reviews of the Mini Universe mention a whining noise, even with isolated power supplies, etc. One review says the only way to fix it is to use the USB power ("However, the only way I got it to operated without a slight whine through the guitar amp was to use USB power").

Interestingly enough, the description of the pedal on Amazon says "Multiple power supply interfaces: Two power supply interfaces, USB Type C or DC 9V adapter (centre is negative),which are suitable for different scenarios. Please use the TYPE C port to power it first. It is recommended to use power bank for power supply,you will get wonderful sound. Or you can use your mobile phone charger for power supply and it requirs above 5V1A power adapter."

The USB thing might be worth a try, but it's also possible that some of the pedals are just faulty and perform this way since not everyone reports the problem. I'd try to exchange it if possible.
I definitely will get a usb cable and try that. Thanks
 
I am a big fan of inexpensive pedals and there are some great ones out there. Recently I purchased an M-vave mini universe (reverb) and an M-Vave Elemental (delay). They are both capable of some crazy sounds but refuse to play nice together. No matter where in the efx chain I put them, if they are both plugged in I get a tone, whine, whatever you want to call it. Not hum or buzz. The frequency is around 300 Hz.
D or D#. Any ideas what would cause this? I have not tried separate power supplies yet. Any suggestions would be helpful. Thanks
Okay, an update. Tried powering both with 9v 300mA which is what the manual calls for….whine still there. Next I tried them at 9v 500mA….whine still there. I tried them on USB power….whine still there. I am waiting for battery clips to try that. Still either one on it’s own works fine but together in the chain….whine. So unless here back from M-Vave, yes they had a costumer service email, I will run them separately on separate pedal boards. Any other ideas are welcome, but short of a designer I’m not holding out hope. Still love them both. Thank you
 
Okay, an update. Tried powering both with 9v 300mA which is what the manual calls for….whine still there. Next I tried them at 9v 500mA….whine still there. I tried them on USB power….whine still there. I am waiting for battery clips to try that. Still either one on it’s own works fine but together in the chain….whine. So unless here back from M-Vave, yes they had a costumer service email, I will run them separately on separate pedal boards. Any other ideas are welcome, but short of a designer I’m not holding out hope. Still love them both. Thank you
While you may love them, I would return them and get something better. May be a drastic view. But you will be happier in the long run.
 
I agree to a degree. There are much better pedals out there but these two particular ones give me sounds that I have not gotten otherwise. I read in a blog that the issue I am having is digital processing noise caused by the manufacture not putting filtering at both ends of the circuit which, yes, is why they are cheap pedals. The common thought is that the whine gets amplified by the adjoining pedals via the power. But I have tried completely isolated power supplies at the proper specs and it does not fix the issue, so I feel it leaks into the audio regardless. So yes short of re designing the pedals to include filtering, buying better quality pedals is the answer. Just a shame though, because whoever engineered these pedals had some good ideas.
 
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