Static or line voltage instability


Maybe some of you guys enlighten me on this subject. A few weeks ago, my CJ preamp suddenly stopped playing in the the middle of a listening session. A volume level of "0" appeared on the led display like it put itself on mute. Since I could not make it switch off mute, I closed and powered it on again and everything came back to normal. I could not see what could have happened even double checked if the unit and the whole system was correctly plugged in the wall suckets. All showed OK.

Last weekend, the same thing happened, even after multiple listening sessions since the first incident. But this time, my power amp blew out all its fuses and the preamp stopped. After replacing the fuses in the amp, I've tried to power the preamp but it will not play. Even the tubes do not glow. So something is wrong, at least with the preamp. A CJ technician told me by phone that my lines could be having problems. I've had dedicated lines for my system for the last 15 years and never had any problems since. I'm a bit confused.

Any ideas ?

Thanks !
Dedicated lines will isolate your system from hash feeding back from other appliances on the line and reduce the voltage drop caused by other appliances drawing on the line. But, if your whole house got a nasty spike, it would not do anything for that.

You should ask the CJ technician about whether you should be using some kind of surge protector. These come in all sorts of cost, from cheap units built into power strips to some fairly elaborate (and expensive) units. Not everyone likes what these do to the sound of certain components, that is why I suggested talking to the CJ technician. Another option is a whole house surge protector that an electrician installs at the main panel feeding the house.

Electrical power related??

Will need a little more info from you.

* How many dedicated lines? Are you sure they are dedicated and not multi conductor separate circuit lines?
For a typical single phase service found in a residential dwelling a multi conductor branch circuits can supply (2) separate 120V circuits with (1) common shared neutral.

With a multi conductor branch circuit the voltage on each 120V hot leg to the shared neutral will be 120V nominal. (From one hot conductor to the other hot conductor, 240V)
Only the unbalanced load of the (2) separate 120V circuits will return on the common neutral conductor to the source, the electrical panel.
The balanced load of the two circuits are in series.

If for any reason the common neutral conductor becomes open or loose it cannot carry the unbalanced load back to the panel. The voltage from each hot conductor to the faulty neutral conductor will not be stable and will swing wildly with the loads on each hot conductor. Just to pick a number, the voltage at the receptacle feeding the preamp could shoot up wards of 150V. The voltage at the receptacle feeding the power amp could drop to 90 volts. The greater the load imbalance the greater the voltage differences.... In your case it could be a poor connection on the return common neutral conductor.

* Have you been having to replace a lot of 120V light bulbs lately?

* Have you noticed lately some lights seem to get brighter when the refrigerator or some other appliance turns on?

The scenario I described above with the multi conductor branch circuit is the same for the electrical service that feeds your home from the utility transformer. You have (2) hot conductors and one shared neutral conductor. If the main service neutral conductor has a faulty connection, high impedance, this will cause 120V nominal voltages on the hot service conductor with a larger load than the other hot service conductor to have a low voltage, and the other 120V of the other hot service conductor to have a higher voltage.

The poor neutral connection could be at out at the street at the transformer.
If an overhead service it could be at the weather head where the power company line connects to your line.
It could be in the meter socket.
It could be at the main electrical panel.

At any rate you would need to hire an electrician to check things out. He can check voltages at the electrical panel and tell if the problem is a poor service neutral conductor connection....... He can also check the branch circuits that feed your audio equipment.
Thanks for your interest !

Yes this had me thinking about getting a quality line conditioner and surge protector but was always told it wasn't necessary with my dedicated lines and overall quality of the electrical supply in our vicinity.

No, no special problems lately with bulbs or appliances. And yes the lines are truely dedicated since I supervised the electrician's work at the time. So four plugs in two double outlets. Each four has its own line going directly to the electric box into four seperate breakers. Don't ask me what amperage the breakers are though, but the electrician told me everything was calibrated to supply a high power home cinema.

Another thing : I'm driving Acoustat 2+2 since January. Their not the hardest electrostatics to drive and I really don't listen at high levels. The amp seems to drive with ease and never gets hotter. But they're quite close to the rest of the gear. Could this be of consequence ?

Thanks !

So four plugs in two double outlets.
(4) duplex receptacles total?
(2)duplex receptacles in (2) two gang boxes?

Each four has its own line going directly to the electric box into four separate breakers.
Each two gang box has (1) cable going back to the panel? Example, a 12/3 with ground NM-B cable? (Romex is a brand of NM-B cable)
Or does each two gang box have (2) NM-B cables each going back to the electrical panel? Example, 12/2 with ground NM-B cable? (4) NM-B cables total? One for each dedicated branch circuit?