@kijanki is absolutely correct. If a device has a plug with a safety ground, it's a Class 1 appliance and defeating the ground poses a safety risk. If you have a noisy ground, lifting the ground isn't the solution. Star grounding can help, as can devices such as the Granite Audio Ground Zero.
Cheater plug safety
So I recently decided to swap out my subwoofer amp for another one I had to see if it worked better with the driver. It did, but I have run into a slight problem. My old sub amplifier had a captive two prong cord. The new one has a 3 prong cord.
The subwoofer amp resides on a different AC circuit than the rest of the system. (Can’t be avoided)
Although the new amp is an upgrade for the sub, there seems to be a ground issue that is hazing up my transparency and sound stage. The system looses some air when the sub amps ground isn't lifted. There is no hum problem through any speaker per se, but just an overall sonic degradation when the ground is left in place. Using a cheater plug just on the sub amp brings back The transparency and it sounds absolutely beautiful.
I read that this can be dangerous, though. (Then why are these created plugs made?) anyway, I also read that as long as the amplifier with lifted ground is connected to the rest of the system via interconnect , and the other components are grounded, then the amp will use the ground from the other circuit that the other equipment is connected to and you are "safe", and only some very unlikely happenings, such as an internal ac wire becoming loose and touching the chassis and standing in a puddle of water should cause a concern. I even had a parasound 750 amp in my college dorm that even suggested using a cheater plug if needed for hum, sooooooo.........
At any rate I am addicted to the sound at the moment and going back without the cheater plug just sounds dull and fuzzy. The system is resolving and shows just about anything you do to it. Mind you, it’s not a night and day difference that would say that there is something wrong with any of the equipment, just a subtle but very tangible improvement that I definitely like and desire. The equipment is working 100% properly.....
It sounds so much better than the old amp and the transparency and air I’m getting right now are rediculous, but I don’t want to get shocked, but the chances seem to be very slim. Can anyone advise?
The subwoofer amp resides on a different AC circuit than the rest of the system. (Can’t be avoided)
Although the new amp is an upgrade for the sub, there seems to be a ground issue that is hazing up my transparency and sound stage. The system looses some air when the sub amps ground isn't lifted. There is no hum problem through any speaker per se, but just an overall sonic degradation when the ground is left in place. Using a cheater plug just on the sub amp brings back The transparency and it sounds absolutely beautiful.
I read that this can be dangerous, though. (Then why are these created plugs made?) anyway, I also read that as long as the amplifier with lifted ground is connected to the rest of the system via interconnect , and the other components are grounded, then the amp will use the ground from the other circuit that the other equipment is connected to and you are "safe", and only some very unlikely happenings, such as an internal ac wire becoming loose and touching the chassis and standing in a puddle of water should cause a concern. I even had a parasound 750 amp in my college dorm that even suggested using a cheater plug if needed for hum, sooooooo.........
At any rate I am addicted to the sound at the moment and going back without the cheater plug just sounds dull and fuzzy. The system is resolving and shows just about anything you do to it. Mind you, it’s not a night and day difference that would say that there is something wrong with any of the equipment, just a subtle but very tangible improvement that I definitely like and desire. The equipment is working 100% properly.....
It sounds so much better than the old amp and the transparency and air I’m getting right now are rediculous, but I don’t want to get shocked, but the chances seem to be very slim. Can anyone advise?
- ...
- 45 posts total
jetter ... does older equipment such as a Dynaco ST70 that has its original 2 prong plug have a greater shock potential? Yes, it actually does have a greater shock potential, because the ST70 was obviously a Class II device. This is why the three-prong, separate safety ground standard was adopted. The Dynaco is sort of like driving a '63 Chevy. It's safe to drive if it's in good repair, but it lacks seat belts, ABS and air bags. |
The issue with the safety ground vs interconnects can be summed up this way: 12 gauge vs. 22 gauge. Safety grounds must carry the full line current in order to trip the breakers safely. This could melt an interconnect ground, possibly explosively, causing a fire, or leave lethal voltages on the outside. Some subs (like Hsu) are double insulated though, so they safely avoid the ground pin and associated problems. So NEVER remove the third prong, and don't buy the Pangea crap which allows you to either. What you could/should try though is a balanced interconnect with the ground lifted at the sub end. If you can do that you'll be golden. Also look for other ground sources such as cable TV or PC's which could in fact be the root cause. Disconnect them to see if the problem goes away, if so add an appropriate isolator. Best, Erik |
- 45 posts total