Is there a point to non isolated brick style power supplies?

Discussion in 'Effects, Pedals, Strings & Things' started by Jupiter Tarts, May 26, 2015.

  1. Jupiter Tarts

    Jupiter Tarts Member

    Apr 11, 2015
    Central NJ
    I can understand the need for an isolated power supply, like any voodoo lab unit, or a one spot which is a very cost effective solution.

    However if a power supply brick isn't isolated, what's the point if it's all drawing from the same power source? Isn't it essentially a one spot that wastes pedalboard space? What's worse is supplies like the mxr dc brick only run like 700 mah despite having so many slots and an 18v. A one spot has at least 1700mah of potential power to draw. You'll never use those slots up before you start running out of power to draw on the dc brick.

    I don't mean this as a knock on those products if they do serve a purpose but they come off as quite inefficient as far as I can see.
  2. gearscrubs

    gearscrubs Supporting Member

    Oct 10, 2013
    Well, if you mount them under the board, they are tidier than a one spot and don't take up board space.
  3. PurpleJesus

    PurpleJesus Staff Member Gold Supporting Member

    Jul 11, 2014
    Trex classic fuel tank is isolated into 3 sections. 12v AC/DC each on their own ground, but the 8 9v plugs share the same ground. I used one for years w zero hum. It's small and tidy and the 12v slots put out I think 500-600ma each so I could run a digital pedal. I have a one spot too but the fuel tank was just easier on a pedal board. More flexibility.

    All that being said.....I just bought a Voodoo Mondo so I could have more outlets, more power, and isolated outlets. Especially since Paul Trombetta is building me a dream fuzz box and said it'd have to be run on isolated outputs.
  4. DaveKS

    DaveKS Member

    Feb 26, 2013
    I really just think it's a marketing stratagy to get the uneducated about power supplies so they think their getting something like a VooDoo or other quality supply for a bargain price just because it looks similar.
  5. 8len8

    8len8 Member

    Dec 25, 2010
    Cost. Not everyone can afford an isolated supply.
  6. amz-fx

    amz-fx Supporting Member

    Oct 18, 2005
    Some non-isolated power supplies will have more than one power regulator on board. This will allow for different output voltages but it also distributes the power dissipation among several active devices so they run cooler and can potentially provide more current than if you had to draw it all through a single device.

    Also, it is better to octopus the outputs (fan out from a common source) than to connect a daisy chain. When you draw current through a resistance there will be a voltage drop, even with the small resistance of the daisy chain. If you have a high current digital pedal on the chain then the problems start. If you fan out separate power cables, then high current devices are not sharing the same ground return as your low current (high gain) pedals and the potential for noise is reduced. (Somewhat like a star ground in an amp) It's not perfect but it works in many applications.

    Best regards, Jack
    Lolaviola and spacefiddle like this.
  7. jordane93

    jordane93 Member

    Mar 10, 2013
    Long Island, NY
  8. gibs5000

    gibs5000 Member

    Oct 27, 2014
    I'd say supplies like the ex brick were great back when most if not all pedals didn't push triple digit mA requirements, the analog pedals get along fine in daisy chains/unisolated power. It's the 300mA strymon, or tonecore pedal with poor power filtering that give rise to isolated power. Now it's about 50/50 between low current and high current pedals on the market. Making something like the brick outdated for today's pedals.

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