Dedicated Line ....... my system SUCKS


Hey there , actually my system sucks current. I have a pair of Cary CAD 500 monoblocks, Maggie 3.6 speakers with a Aesthetix preamp. I have had issues with amps shutting down . I am going to create a dedicated circuit for the above mentioned gear . I can do a couple of adjacent locations. Currently have a 15 amp line for the entire room . I am looking to those of you who have incite . what did you do to obtain the maximum amperage from the breaker box to the wall outlet ? did you notice a improvement ? this dedicated line of 10 gauge wire is only 12 feet to the outlet. It seems as if a 20 amp receptacle is the highest rating for a duplex outlet - I was going to install a 30 amp breaker but not sure if I would realize its potential. In closing , a note for those wondering , the amps were checked out by the manufacturer and are fine. the speakers are on 25 foot runs of Kimber 8tc. thanks in advance for your thoughts and advice. PS - I have been known to crank up the volume
lezdam
when i bought my house i had a dedicated line run straight from the breaker box.it works like a charm and provides all the clean juice my manley monoblocks crave...
Read the thread about dedicated line on 1-27-2011, good info.
I'm guessing this is the thread.[http://forum.audiogon.com/cgi-bin/fr.pl?htech&1296186030&read&3&zzlExtra_action]
I have the same amps and had 20 foot speaker runs. The amps were heating up (Oscillating) and close to shutting down. I found that the resistance/inductance of the long speaker cables I was using was the problem. Once I changed the cable, and the length, everything was kool.
this dedicated line of 10 gauge wire is only 12 feet to the outlet. It seems as if a 20 amp receptacle is the highest rating for a duplex outlet - I was going to install a 30 amp breaker but not sure if I would realize its potential.
Lezdam,

I doubt your problem is on the electrical power side. One quick way to check for VD (voltage drop) is with a volt meter connected at the receptacle the audio equipment is plugged into. Take the reading with the equipment turned on and playing dynamic music with the volume cranked up to where you listen to it loud....

If the voltage does not sag during the test then you do not have a VD problem.

As for using a 30 amp breaker it will not change anything. The guts in a 30 amp breaker are the same as in a 15 amp breaker. Only the trip unit is different.

Also the maximum breaker that can be used for two or more 15 recepts or a 20 amp recept is a 20 amp.

If the 15 amp breaker is not tripping the breaker is not the problem.

Per NEC code a 20 amp receptacle, (NEMA 5-20R) must be connected to a 20 amp branch circuit breaker.....

As for your problem Markus1299 post is more than likely the cause and solution. Shorter speaker wire.
I agree that there would be benefit, if you are having a dedicated line installed, look into two dedicated lines and put your amplifiers near your speakers to use shorter speaker cable runs (and longer interconnects). Multiple posts on the advantage of that design.
One of the beautiful things about monoblocks is the ability to remove speaker cables from all equations (cost, sound, amp instability, etc). I have mine positioned behind my speakers such that the binding posts line up. Only need two inches of "cable" to make the connection.
I use 10 guage romex, about 6 feet from the panel and I use 30 amp breaker.

All this for a two watt amp.

It's not overkill if it sounds great .
One thing to look at is the actual line voltage into the house.
You might only have 208v service. It is unusual to see such voltage but it is out there.
15amp service at 120v is capable of handling a 960 watt device. At 104v the 960 watts drops to 721 watts.
One thing to look at is the actual line voltage into the house.
You might only have 208v service. It is unusual to see such voltage but it is out there.
208 volts comes from wiring across two phases of 120v 3-phase service, which is only found in commercial buildings or larger apartment/condo buildings.

Of course one should never attempt to power electronics in this fashion. But for a dedicated 120v line, the wiring practices are equivalent (electrically) to residential "split phase" 240v service.
Maybe the power amps aren't the best match for the maggies demanding load.

A lot of folks like to run them with high power solid state amps, and yet they were originally partnered with AR tube amps.

Are you running the correct transformer taps on the amps for the speakers?

And of course it could just be that you are not getting all the power you are paying for from the electrical company, especially in the summer months.

If you can, check the voltage from your receptacle (if you don't know how, hire an electrician) and then if it is below acceptable rating, call the electrical provider and ask them to check things out and up the voltage to your house.

Years ago I had a pair of Metner mono blocks that kept shutting down.
Ed fixed then twice, and had me do a check on the voltage and sure enough it was low.
A SAFE way to check line voltage is to get a Kill-A-Watt meter....They are about 25$ or so these days. Plug in the meter and plug the amp into the meter. You'll get a direct voltage reading. You can also measure current to the amp as well as watts / VA / Power factor.
As a first pass at the incoming power, I'd look for voltage sag as current draw increases. That to me would indicate a 'soft' line.

Maggies are NOT a bad load. They have generally moderate phase angles. They are of low sensitivity which is made up for, in no small part, by the dipole / linesource behavior which is maybe good for a +3db. The do have, however, pretty high power handling capacity so while say.....100 a side works the overachiever / person who likes it LOUD in a larger space can make use of some of the big 'd' stuff or the higher powered tubes. The AR mentioned above, is a natural. Magnepan shows well with Bryston, too. I'd LOVE to try some Pass, too, the INT-150, but that's dreamland, for me.

Your Cary should be MORE than enough, if fed proper line voltage, though at less than 1lb / watt for a conventional amp, a little 'light' perhaps?