Power supply

Vasfed · Post by **Vasfed** » Mon May 09, 2005 4:30 am

Some time ago something happened with with power supply in my house, and now i'm experiencing -50Db hum when recording.

i'm in no doubt that is time to do something with power, but there's several ways:
buy an online-ups or power conditioners...

any suggestions?

Post by **garyb** » Mon May 09, 2005 11:49 am

have you measured the voltage? have you made sure you have a decent ground? if you aren't comfortable checking these basic things out, then first, call an electrician!
you may have a ground fault or other condition that may be dangerous to you or yuor gear.

<font size=-1>[ This Message was edited by: garyb on 2005-05-09 12:51 ]</font>

Vasfed · Post by **Vasfed** » Thu May 12, 2005 11:59 am

oh, sorry, a havent said - AC 220V 50Hz, all equipment is connected to same power source, so there should not be any ground loop.
Also i tried to plug off all devices not involved in recording - same result: computer with pulsar2 + amp + dynamic mic, the only thing i managed to achieve - 10Db less noice by placing power cords farther from devices

ps. here in russia most elecricians even have never heard about ground loops, sound studios etc

so that is not a solution

Post by **garyb** » Fri May 13, 2005 3:26 am

yes, but have you determined if your wiring is grounded properly(in the house) and if you actually have 220v 50hz? electricians may not know about studios, but they will know grounding, phase and voltage.

astroman · Post by **astroman** » Fri May 13, 2005 9:25 am

On 2005-05-12 12:59, Vasfed wrote:
... the only thing i managed to achieve - 10Db less noice by placing power cords farther from devices...

ouch, that doesn't read good at all...

I'd assume there's no ground at all until the opposite is proven - just for safety's sake.

cheers, Tom
could you list exactly what gear is connected ?
and don't underestimate the danger: I also have a slightly 'adventurous' electricity at home, which requires switching the gears main ground depending on setup.
In a certain situation the 'ground' wire has a 'felt' voltage of at least(!) 40V. If something like that enters your digital gear that's not the most appreciated thing...

<font size=-1>[ This Message was edited by: astroman on 2005-05-13 10:34 ]</font>

bassdude · Post by **bassdude** » Sun May 15, 2005 5:52 pm

You have a serious ground problem. Also, earth loops can still occur even when all gear is connected to same power source.

Vasfed · Post by **Vasfed** » Fri May 20, 2005 12:51 pm

config is pretty simple - audio routing: PC with pulsar2 directly connected to 2 krk active monitors, and to ART tube-mp preamp, which is connected to senheiser dynamic mic.
also there're optical adat-connections, but optical cables cannot generate analog noice

all devices connected to the same power filter, so all ground wires are connected, but only to each other.
few friends on mine solved similar problem by using an online ups