There is still a lot of confusion about power supplying your effects in general.
Wrong use of power supplies can cause nasty hum and even severe damage to your precious effects and gear.
You simply want them to run properly and only worry about Rock’n’Roll.
Here are some tips from the Doctor.
1. Voltage DrNo-Effects use 9V. To make a right purchase to power up, you need to know “How many volts does the pedal(s) require” One nine-volt supply can drive as many 9V pedals as you like, depending on the Current ( mentioned in 2 Current).
2. Current The most common mistake that’s been made is to power up your whole pedal board with one small power supply and daisy chain it, with too low current!! So.. check out “What’s the current draw in milliamps for each pedal that needs to be powered!” If you’re using more than one pedal, add up the total current draw of all your pedals and make sure your chosen supply can positively handle that total current.
For example, the supply might be capable of delivering 500mA in total, but if four pedals use 150mA each you can only power up three pedals (450mA). There are many pedals that could use this amount of mA but there are numerous pedals that require more, so measuring is the only way to be sure.
(A link to measure effects current draw and a way to do this the easy way, will be posted soon on this website).
3. Connector type DrNo-Effects use Regular DC Plugs of 2.1 mm. What type of plugs/pins are required? Variations are almost uncommon and if they are unusual, they are included (most of the time).
4. Polarity Tip/negative or Tip/positive? That information can be found in your effects manual, website or added sticker/info on effects. To accidentally switch polarity (Germanium fuzzez for example) will ruin and severely damage you effects. MAKE SURE YOU HAVE THE RIGHT POLARITY. You can find polarity on your Power Supply as well, to have a sure and safe match.
5. Other things you need to ask your Musicstore are:
Ask if the power supply is well filtered and regulated and make shure they are so, others can be the cause of noise and interference. For Example DrNo-Effects are not compatible with “One Spot” that are not regulated.
They cause this nasty hum and sizzle noice. DrNo-Effects are professional grade products that need professional grade powersupply (soon available from DrNo-Effects).
If you set and figured out the above, you could find out that there is a variety on Voltage/Different polarity and Current. The advice is to create isolated outputs.
Unfortunately these require a bigger investment. Second option is to isolate by different Power Supplies.
Most higher-end power supplies have isolated outputs, which can help to minimise the kind of annoying and unwanted noises.