Power Supply/Surge Protector for Reducing Hum

[spector_boogie]

Years ago when setting up my recording/work desk, I had an annoying hum in the playback chain between my computer, mixer, and monitors. I tried a ton of fixes, non of which worked. Finally, someone suggested this little inexpensive box, and the problem was solved.

https://www.amazon.com/Behringer-HD400-Ultra-Compact-2-Channel-Destroyer/dp/B000KUD2G4?th=1

I don’t even remember where I have it in the chain at this point, but I’ve been recording happily ever since.

That looks cheap enough to try out for sure! I can run my pedalboard into that, and then out to my Focusrite or amp and see what it does.

Thanks for all the feedback, and I will say the problem isn't really that bad, it's just the more time you spend with good headphones/in ears or monitors, the more you notice this little stuff and work on chasing everything in your signal that isn't 'right', the best you can. And when you mostly play live, which is what I used to do before my hiatus, it's not a big deal. Now it's becoming more so as I am getting into recording, etc.

 

[bholder]

A power conditioner isn't going to help with your problem - you need to work on your bass and/or or the actual sources of the hum - which isn't "dirty power". It certainly isn't surges or RFI that you're fighting. And no, being in the "sticks" doesn't make your power dirtier - there are far more interference sources in a city.

Sure, more interference from outside influences, but the line equipment out here is generally way out of date and of lesser quality than closer in. Been here 30 years, that has been my experience. We're an afterthought to the power company out here - first to go out, last to get restored, small long branch circuit with only 34 houses on it. We get the dregs when it comes to power service.

 

[Drredplate]

While good earthing is essential for electrical safety very often it does not help with mains borne noise.
Suggest try what has worked for others mentioned in previous posts.
Mains noise filters do exist but effective ones are usually expensive

 

[Stevorebob]

Is your computer a laptop? If so, it may be the power supply that’s causing the hum. To check, simply unplug the power supply from your laptop. To remedy, either get the power supply as far from your bass as possible or unplug it when you record.

 

[spector_boogie]

Is your computer a laptop? If so, it may be the power supply that’s causing the hum. To check, simply unplug the power supply from your laptop. To remedy, either get the power supply as far from your bass as possible or unplug it when you record.

Actually no it's an HP desktop I've had for a while. I need to spec a new build that can better handle modern recording stuff and interfaces, but this does okay for now.

However, I will check when I get home and ensure that my computers/monitors/etc. are plugged into a different outlet than my music equipment. I have just regular 'store quality' (like a G.E. or something) power strip the music stuff is running into, then a wall outlet. But, I may have another power strip for a piece of PC equipment into that same outlet, which could be a little part of it.
My Focusrite is about 6' away from my PC it's plugged into, so I don't think that's getting any interference?

Also, side note, I know there are a lot of 'snake oil' AC-style power cords out there, but, is there any ones specifically to look at buying? The ones I have are from when I last played regularly, about a decade ago, so probably could use a refresh. And I tend to use a longer one live since you never know where the power outlet is going to be stuck at a particular venue. I know there are actual artists that 'endorse' power cables that kind of get derided/ribbed about such, but, there probably are better quality ones than others- I'd think?

 

[micguy]

Sure, more interference from outside influences, but the line equipment out here is generally way out of date and of lesser quality than closer in. Been here 30 years, that has been my experience. We're an afterthought to the power company out here - first to go out, last to get restored, small long branch circuit with only 34 houses on it. We get the dregs when it comes to power service.

Even if the power company's equipment is outdated, I sincerely doubt that the reason you're getting noise has to do with the "quality" of the power that your utility is delivering. You may have low voltage (or high voltage) at times, but that has nothing to do with noise in audio circuits. If you have dimmers on lights (or some of the LED light fixtures), the fields from them will most likely be FAR more of an issue than anything the power company does to your power.

My previous house was built in the late 1950's, and the power to it was probably from that era when I bought it in 1991. A few years in, the whole neighborhood got rewired - new wire, new transformers, etc. We stopped having power outages, the lights no longer dimmed at odd times, etc, but....all the hum and buzz issues persisted - they were issues with the way the house was wired, dimmers, etc.

Between a few houses, and doing sound for events in North America and Europe, any time I've experienced hum and buzz issues, it was always something on site - never the power company.

 

[Stevorebob]

Actually no it's an HP desktop I've had for a while. I need to spec a new build that can better handle modern recording stuff and interfaces, but this does okay for now.

However, I will check when I get home and ensure that my computers/monitors/etc. are plugged into a different outlet than my music equipment. I have just regular 'store quality' (like a G.E. or something) power strip the music stuff is running into, then a wall outlet. But, I may have another power strip for a piece of PC equipment into that same outlet, which could be a little part of it.
My Focusrite is about 6' away from my PC it's plugged into, so I don't think that's getting any interference?

Also, side note, I know there are a lot of 'snake oil' AC-style power cords out there, but, is there any ones specifically to look at buying? The ones I have are from when I last played regularly, about a decade ago, so probably could use a refresh. And I tend to use a longer one live since you never know where the power outlet is going to be stuck at a particular venue. I know there are actual artists that 'endorse' power cables that kind of get derided/ribbed about such, but, there probably are better quality ones than others- I'd think?

Okay. Probably not the issue then. The thing with laptop and tablet power supplies is that electric guitars and basses, especially single-coil pickup instruments, easily pick up radio interference (rather than AC power noise).

About AC noise, what I’ve learned from those who know is that an appropriate power cable (Hosa, for example) is all one needs. The 6 to 8 feet from the outlet to the equipment has little impact compared to the 60 to 100 feet from the breaker to the outlet. I’ve no experience with so-called power conditioners.

 

[Killing Floor]

RFI filtration only works if it's radio frequencies bleeding through. If it's some sort of ground hum or something being carried all the way from the pole, RFI filtration won't do anything for that.

Correct. That’s why I said it will help but won’t eliminate everything. Some gear is also more prone to noise. I will use a gate sometimes but I really don’t want to.

 

[spector_boogie]

Okay. Probably not the issue then. The thing with laptop and tablet power supplies is that electric guitars and basses, especially single-coil pickup instruments, easily pick up radio interference (rather than AC power noise).

About AC noise, what I’ve learned from those who know is that an appropriate power cable (Hosa, for example) is all one needs. The 6 to 8 feet from the outlet to the equipment has little impact compared to the 60 to 100 feet from the breaker to the outlet. I’ve no experience with so-called power conditioners.

Thanks for the info! And yes, I totally agree. I probably have some AC cables that are from old PCs at least 15-20 years old lol, it was all just in a box of my old gigging gear that thankfully has been in A/C since then, but I am upgrading all my pedalboard patch cables, practice and live cables (I use a Relay G50 live), etc., speaker cables, so figured a power supply cable would be in the mix too.

 

[seamonkey]

Many of the hum reducers are isolation circuits. Or they are heavy on DSP to target the 60/50 and harmonic frequencies.

Primarily you need good shielding.
Get stuff into balanced lines as close to the source as you can.
Short well shielded cable from the bass to the interface or DI.
If you have a ground loop even with balanced lines, it can be measured with a clamp on DMM

You can wrap the cable around the DMM current probe several times is yours isn't sensitive enough.

I note I have a Macbook and Lenovo and neither has a ground. The two prong plugs can plug in either way. They are not polarized. My interfaces are powered off the USB, And, yet I don't get hum. Many power supplies for pedals plug in either way and also don't have a ground. If I unplug the bass and touch the tip of the 1/4" I will get a buzz as I as a person am not shielded. If I was sitting in a Faraday cage it might be different. Plugging into FOH or some recording interfaces provides a single star ground comes from the board. There won't be a ground loop as it's a single point of ground.

 

[Stylee Mousse]

Thanks for all the feedback, and I will say the problem isn't really that bad, it's just the more time you spend with good headphones/in ears or monitors, the more you notice this little stuff and work on chasing everything in your signal that isn't 'right', the best you can

it is also important to have some perspective on how much the final few % of improvement is worth in money and time.

I have played for a long time in touring and recording bands, worked as a live and broadcast sound mixer and recorded music. At this point I really don’t chase perfection for recording in any way because I don’t feel it is time well spent. I strongly prefer working on tape and have No problem limiting my track count and automation because spending hours fiddling with a daw try to “perfect” tunes just makes them less alive.

I’ll take some noise here and there because 97.5% of the time it makes no difference at all to the final tune’s quality.