Post by straylight on Oct 28, 2018 19:46:31 GMT -5
I've never really done pedals. I had a handful of pedals as a teenager and quikly moved on to a collection of rack toys. Now i'm looking at pedals as devices for inspiration and I've bought a few. I'm trying to use an EHX Memory Man Deluxe which requires a standardish pedal power supply. It works ok on its own, however I've got a tuner and an overdrive that I use quite often. TU-3 and a Crayon if it matters. They work fine without the memory man, both on battery and with a daisy-chain cable to a single psu. If i've got the memory man in as well, all is good if the other pedals are on batteries. If I dare use the daisy chain I hear a pulsing sound that matches the fliver of the tempo light of the memory boy even when the memory boy is in bypass.
Is there any other solution to this other than let the memory boy have the power supply to itself? Will using another power supply for the other pedals just pick up the noise anyway?
Fled across faculty from MechEng to CompSci, now revisiting the bit in between for analysis of an offshoot of a hobby... oops.
Post by blademaster2 on Oct 29, 2018 11:20:04 GMT -5
This is close to the systemic noise challenges that my team encounters all of the time in my day job.
My initial thoughts are to use a common power supply that has better load regulation (does not alter its voltage output when faced with changing levels of current drawn from it across a wide range of frequencies), also referred to as lower output impedance. If that is not desirable or possible, then separate power supplies that are all referenced to the common 'ground' voltage (outer connections on the jacks, and not the centre) might work just as well.
If the memory man uses an internal switching power supply for local regulation, your external common supply might need to be able to supply current at pretty high frequencies without added noise on the voltage. This could even mean it is influenced by the power cabling resistance/inductance and be very difficult to eliminate entirely. As such this might continue to be a challenge, so separating the supplies might still be needed to give you the least noisy results.
Beyond using the separate supplies, which works as you have said, trying a different supply might do the trick. If not then go from there until the problem is resolved.