# Any insight into the Mefe MP2 power supply?



## Verne (Dec 29, 2018)

I am searching for a budget minded brick power supply. This is stated to be isolated and does digital and analog. It fits into the budget I have and does enough pedals to cover me for a while. I have 6, with one definitely being digital. Has anybody ever used this one? I looked at the Caline and Donner bricks, but they proved to not be isolated. Before I order this, I was hoping to get a little input, if anybody has any. 

I really only have a bit to spend, and the 1 spot combo has been mentioned makes noise with digital. 

https://www.amazon.ca/Isolated-Pedals-Supply-Guitar-Current/dp/B07HJ3C9PW


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## fretzel (Aug 8, 2014)

I know that my first Donner is isolated as I tested it when I first got it. Currently running 2 digital pedals off of it with no issue. 

Haven’t tested the second one as of yet. Did try it back to back with my One Spot and it is every bit as quiet.


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## Verne (Dec 29, 2018)

I don't gig or leave the house, so I can't justify a Voodoo lab or anything over $100 really. This one I posted says it's truly isolated, and the price is right. I found a youtube video where a Donner DP2 (one I was looking at) was tested, and with a meter, he showed it wasn't isolated. Is the Donner you have the DP1?


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## fretzel (Aug 8, 2014)

Yes I have the 2 of the dp-1. Just noticed now that the dp-2 has 500mA on tap for the 18v out. Wish I had of bought that as that is what I need. May have to get a third. 

Was just reading a comment on YouTube with a guy saying he powers his strymon with the dp-2 just fine. 

I wouldn’t be surprised if the donner and mefe are the same inside. A lot of the Chinese companies rebrand/rehouse their stuff.


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## mhammer (Nov 30, 2007)

I have one of these. I assume it is probably not much different than Donner or other-branded Chinese PS units. They are all "isolated" to one degree or another. The 100ma current limit on the outputs indicates use of a 78L09 regulator, or similar, which necessarily implies that each of those 9V/100ma outputs is :isolated" from each other.

The bigger question is whether they also include the sort of line filtering that would prevent any digital clock spikes from either leaving the PS brick, or coming in from a pedal. I would say that your concern with digital noise is probably legitimate if your digital pedals are more than a half-dozen years old. But given how much of a nuisance it was for manufacturers to deal with the fallout from heterodyning noise when 2 or more digital pedals shared power, they wisened up and included the relevant filtering in the pedals themselves.

The MeFe looks reasonable, although I'm a little sceptical of the 18V output, given that the input is 12V. The "upverting" of the main supply voltage will probably involve a charge-pump of some kind. I'm more comfortable (though perhaps unnecessarily so) with a supply that starts out higher, and only down-regulates, as in the case of the Caline unit here.


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## fretzel (Aug 8, 2014)

Just tested the second and it is not. Would lead me to believe the first one isn’t as well. I run a Digitech TR-7 and a Ventura (both digital) along with 8 other analog pedals with no problems. YMMV


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## Verne (Dec 29, 2018)

My digital pedal is the TC Electronics Skysurfer reverb. It's a 9v pedal from what I read on their site. I got it in a trade, and have no idea on when it was released. I have no pedals over 100mA, and nothing that needs more than 9v. That's just what I own now, but likely won't be buying any pedals in the foreseeable future. I just don't want to buy one and have it screech or hum at me.


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## Verne (Dec 29, 2018)

fretzel said:


> Just tested the second and it is not. Would lead me to believe the first one isn’t as well. I run a Digitech TR-7 and a Ventura (both digital) along with 8 other analog pedals with no problems. YMMV


This is what I am afraid of about buying off Amazon. At least if L&M had more budget minded isolated supplies, I'd buy there and return it if it gives me noise.


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## fretzel (Aug 8, 2014)

Just an FYI, the Caline pictured above is the same as the DP-1. I will definitely be picking up the DP-2 now that I know the 18v has 500mA out.


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## fretzel (Aug 8, 2014)

The Donner is available as a prime item. Very returnable. A couple items I’ve had issue with from Chinese vendors I have got a full refund and got to keep. 

Honestly, check the return policy and see who is on hook for return mail. It is a solid psu.


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## Verne (Dec 29, 2018)

I just noticed a review posted on the one I posted about. It's dated today and he states he tested it and it is isolated. I am not a prime member as I don't really order often enough to pay the fee.


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## fretzel (Aug 8, 2014)

One of the things about prime, typically the item is delivered from Amazon warehouse. More ownership on their part with that. Easier returns.


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## Verne (Dec 29, 2018)

mhammer said:


> I have one of these. I assume it is probably not much different than Donner or other-branded Chinese PS units. They are all "isolated" to one degree or another. The 100ma current limit on the outputs indicates use of a 78L09 regulator, or similar, which necessarily implies that each of those 9V/100ma outputs is :isolated" from each other.
> 
> The bigger question is whether they also include the sort of line filtering that would prevent any digital clock spikes from either leaving the PS brick, or coming in from a pedal. I would say that your concern with digital noise is probably legitimate if your digital pedals are more than a half-dozen years old. But given how much of a nuisance it was for manufacturers to deal with the fallout from heterodyning noise when 2 or more digital pedals shared power, they wisened up and included the relevant filtering in the pedals themselves.
> 
> The MeFe looks reasonable, although I'm a little sceptical of the 18V output, given that the input is 12V. The "upverting" of the main supply voltage will probably involve a charge-pump of some kind. I'm more comfortable (though perhaps unnecessarily so) with a supply that starts out higher, and only down-regulates, as in the case of the Caline unit here.


Looking at this one now. I found one that even has a bonus cable that turns 1 cable into 8. The only thing is one of the images shows what looks like a European prong. I want to order this, but if you ordered off Amazon.ca did you get a correct North American adapter plug ? This is also $20 cheaper and all on one side. The cable bonus is a $13.99 value. Okay, maybe it wouldn't get used, but never hurts to have since it's FREE!!!


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## Verne (Dec 29, 2018)

https://www.amazon.ca/gp/product/B07C2TYSNL/ref=ox_sc_act_title_2?smid=ABU8D46AUHT5X&psc=1


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## fretzel (Aug 8, 2014)

Did you see the Mefe mp-1. Extra 500 outs.


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## Verne (Dec 29, 2018)

I don't have any pedals that require more than 100mA. Even the 300 ports are overkill, but it never hurts just in case. Although seeing that is an idea. I emailed the seller of the Caline and asked about the adapter plug. Hope they respond sooner than later.

The digital reverb pedal is the hungriest at 100mA. The others are all under 6mA. I am just going to order the Caline since it has the freebie.

Thanks for all the help guys.


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## mhammer (Nov 30, 2007)

Verne said:


> Looking at this one now. I found one that even has a bonus cable that turns 1 cable into 8. The only thing is one of the images shows what looks like a European prong. I want to order this, but if you ordered off Amazon.ca did you get a correct North American adapter plug ? This is also $20 cheaper and all on one side. The cable bonus is a $13.99 value. Okay, maybe it wouldn't get used, but never hurts to have since it's FREE!!!


I got mine off a local Kijiji ad from a guy for $25. The daisy chain 1-into-8 cable should only be used with analog pedals, and even there you need to calculate total current draw so that it won't exceed maybe 60% of what the specific outlet on the brick says. So if the outlet say "9V / 100ma", best to stay within maybe 60ma total or less. Pulling more current makes things run hotter, and when they run warm, they can drift off-spec. And as you can see, very few, if any, power bricks or wallwarts have slots for ventilation. Whatever heat is generated inside stays inside.


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## Verne (Dec 29, 2018)

My pedals draw very little juice. I only have 6 total anyway, so this may not get used. It came free with it, so figured, why not?!?
The only 2 pedals I can't completely get much info on are the rather aged Matrix SR3000 tuner, and the Joyo JF-15 California sound pedal. I am thinking the tuner is likely analog because it's got to be near 20yrs old now. The Joyo I just bought last year, but have no real info on it aside it's based on the Tech21 pedal of the same name.


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## fretzel (Aug 8, 2014)

I have the American sound. Draws a whopping 4mA.


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## Verne (Dec 29, 2018)

Cool. It's not digital though is it? I assumed since it's a knock-off, that it wouldn't be.

The Cali sound really makes a difference. Especially through the Micro Terror. Not as noticeable through the H&K Tm5. Although, I have the pedal set for a nice clean tone with a little bottom end.


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## Verne (Dec 29, 2018)

I ended up getting the Caline CP-05 and like it. With all 6 pedals plugged in, it works perfectly fine. I was worried about the digital pedal creating noise, but it isn't the one that does. The Joyo Cali sound creates a hiss sound. Not a really loud hiss and it disappears while playing. It actually sounds like the hiss you get off a cassette tape from "the old days". I can use 5 pedals (minus the Joyo) and everything is quiet and works as it should. $44 (with the free 1 into 8 cable inc) and I am a happy player.


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