Lfan
Good day good people!
I hope you can be of assistance.
I have a Morley Power WAH which I would like to get a power supply for. According to its specs it requires a 9V DC which is regulated, if not regulated it produces a HUM.
Any idea where can I get a regulated 9V DC ?
Gearhead
The specs you mention are stating the obvious since any audio equipment will hum if you give DC powered amp stages a rail voltage containing enough ripple. You make ripple by not putting enough capacitance, whether you regulate or not.
What we will need to know to answer the question about your supply, is how much current your effect draws at 9V.
AlanRatcliffe
Agreed. Smoothing caps are more the issue for hum. Some pedals do require regulated voltage - specifically many digital pedals, but I've never known a wah to be that fussy of voltage.
Manufacturers often try push you to their own supplies in their literature...
So find out what current draw the wah has, take a trip to your local music store and see what they have. As long as the voltage is the same and the current is the same or preferably higher than the pedal's draw, you should be fine.
Lfan
Thanks allot guys for your info.
According to the Morley website, the pedal requires a 9V DC 300mA regulated, center polarity negative adapter. They do mention all their power supplies are regulated to combat hum and produce noise free power.
I was weary off them trying to push into purchasing one of their own branded power supplies which costs allot more than a generic one of the same specs, hence I did take it to my local electronic/radio shop to try one out. They did have a 9v DC 500mA, however it was not regulated and it hummed like crazy, so much that it is unplayable. They only difference in the specs is that the morley branded adapter is regulated and the generic one is not.
Psean
And check polarity. Not sure if Morley uses the more common centre - (Boss style) , or centre + like some of the older EHX and DOD pedals.
EDIT: You beat me to it ?
AlanRatcliffe
I'm not saying use a generic (those multi-voltage supplies are truly awful - I wouldn't use one on my doorbell). And no, they are not properly smoothed, so do hum with audio gear.
The branded supplies from other pedal manufacturers (Boss, etc.) are usually OK - and relatively easy to get hold of.
Lfan
Thanks Alan!!
Those generic units are also quite massive for a pedal board as well, so not very practical too.
I'll definitely pop in to one of the music stores around me to try out a proper pedal adapter.
Thanks again guys
babbalute
When I studied some electronics(and that's a few years ago) a regulated power supply was a power supply that gave a fixed output voltage with a maximum current that could be drawn from it. These could be smoothed (you use high or lower quality high capacity capacitors.
There are also variable power supplies that can give a variable output voltage e.g. between 5 and 30V DC with again a maximum current output. The current out put could be higher at e.g 5V DC compared to 30V DC but this depends much on the design of the voltage regulator. Some will automatically adjust the output voltage or current depending the required voltage or current. Floating DC power supplies.
The cheapees are just simple voltage regulators with a small capacitor in them just to smooth little and should be used for non hi-fi or musical applications or any application with radio-frequencies or amplification. Otherwise you will increase the amount of hum noise.
The more expensive ones will have a greater smoothing capacity, be bigger(due to number of capacitors and other relevant components installed) and obviously more expensive to eliminate any hum.
In the old days and still now we used/use transformers to reduce the input voltage (e.g 220V) to a voltage (about 1.4x higher) then the required output voltage(in theory, in practise the output voltage of the transformer is always a bit more than the required regulated output voltage)
Modern regulated power supplies are switch mode power supplies(yours desktop computer or notebook has one of these) They can produce higher currents at a required output voltage and they can be made for virtually any required output voltage and current. These units can take almost any input Voltage as well e.g anything between 90 and 240V AC. The small block regulators with single or multiple output jack connectors complain quickly if the input voltage is more than +/-10% out the one they indicate. (e.g 230V +/-10% which in SA is easily achieved)
Outside the standard ones available(good electronic component shop) this becomes expensive. Good ones include a lot of smoothing/filtering as well and they can be used in HI-FI and musical instrument applications.
That no one manufacturer of pedals goes to the trouble of designing a good power supply for their pedals I cannot understand. As normally more than one pedal is used it would not be a bad idea to use a switch mode power supply that give of the following voltage(at least one output connection for each): 5 V DC, 9V DC 12V DC, 18V DC and maybe even 24V DC. The output current of this device should be at least be 2~5Amp(that's 2000~5000mA) Sound a lot ? 10 x 300mV pedals is 3000mA(if one runs at 300mA) so a bit of reserve current is always good to have.
Of course one could always carry a box of spare 1.5V in various sizes and 9V batteries with you atleast your pedals will still work if Escom switches of the power.
petercornell
TGF
If you want to pursue this, I can add a regulator to a PSU for you.
But beware, if you need a 9v output, the PSU needs to be 12v or more.
Peter
