Read again: "consider isolated grounding". I am not recommending it, but many users do so from experience so I just threw that in. However think about what is your objective? Are you more intersted in good sound or in meeting code? Poor analogy: When I'm in a hurry to get somewhere, the last thing I worry about is obeying "the rules" (speed laws) |
Craig, I was referring to Bob's recommendation to have an isolated ground which is not to code. |
Yes that is correct & it's another good point! All the evens are on one of your 120V phases and all the odds are on the opposite phase. Best to use the same side for everything, hopefully most all the noisy loads in your house are wired on the opposite phase, or can be rewired that way (I did that). Don't unbalance your transformer's loading too much though. |
Thanks to everyone for your excellent input and advice. One more question--someone told me that when running multiple lines out of the box you need to run them all from either odd or even outputs (2,4,6 or 1,3,5 etc.) in order to avoid phase problems (I hope I'm explaining this right). Can anyone verify that? |
Just for the record: (1) My sub-main box is also grounded back to the main. (2) What Liguy calls an isolated ground is not isolated in my system, it is a secondary ground and is totally acceptable to Oregon electrical code.
Also, just for the heckuva it, I disconnected the secondary ground (the one from the submain) and it made no difference either musically or to amplifier hum-- this indicates to me me that the main (house) ground is good, and there is no safety issue involved.
I actually would not have needed to put in a sub-main ground, but it seemed like a good idea at the time, and was not expensive. In fact I got that ground info. from an Agon thread of long ago. Cheers. Craig |
Good suggestions and comments. I have found three 20-amp lines and making the complete power connection to equipment the best I could was better than the extra costs and grounding issues that getting beyond 3 lines would get me into. Good sockets, power cords and power controllers got me solid results. The DIY types in http:\\audioasylum.com really have shared recipes for getting excellent results for less money. Take a look in the search engine.
1 for two mono block amps (PS 600)
1 for analog front end (PS 600)
1 for the digital stuff connected to a dedicated the Chang or HTS connected to a dedicated Chang Lightspeed 6400 mkII s.
Music and HTS never are on at same time - period. I guess I don't mind switching in the one Chang for the other. |
Sean and Liguy; Thanks for the input re grounding. I've got a call into the electrical company that installed my system to clarify this grounding issue. Craig. |
You can do a dedicated "ground" for your audio system so long as EVERYTHING connected to it is on the same ground. In other words, using a dedicated ground for just the amps and then having your sources, preamp, etc... tied into the common house ground WILL result in a hum and a possible safety hazard. Same thing goes for an audio system that does double duty as an HT system. If the TV, Satellite, DVD, etc... is tied into the house ground and the audio system is on a dedicated ground, once again, you've got problems. In other words, ANYTHING that is connected to the preamp or mode selector HAS to be tied to the same ground to work properly, minimize noise and be safe. Individual electrical codes may have a LOT more to say, so be careful and investigate first. Sean
> |
Liguy; I had my whole dedicated system installed by a licensed electrician from a reputable business here in Oregon, and they had no problem with grounding the sub-main box. I assume you're referring to my post? Craig. |
I agree with Bob Bundus and his suggestion on how many and what type of lines to run. I am not sure I agree about break-in of AC power lines (call me a skeptic if you will) and definately disagree about an isolated ground due to code violation and safety issues. Ground has to be tied back to the box somehow. Legally you can not have 2 separate and isolated ground systems being feed by one service. At least not here in New York. |
As Bob (above) suggests, wire really is directional soundwise. I put in a sub-main and then ran four dedicated lines from the sub-main to four Hubbell duplex outlets.
Well the 60 ft. of stranded 6 ga. wire from the main to the sub-main was definitely directional. When run one direction, music was very soft and uninvolving, but when I reversed the wire and listened, music was much more live, dynamic and natural (BTW, I did this testing with this large wire out of the wall, ie before final installation).
I learned of this from Redkiwi, and just had to try it out. I'm a believer. Yes, 6 ga. wire is overkill, but I already had it. I also put in a dedicated ground from the sub-main, but am having a problem with my amps humming-- still working on that. I think Docroc gives good advice there. Good luck. Craig |
It really depends on the draw of the units....
In an all audio system, I use two 30 amp dedicated lines, one for each big Krell amp. And, I then have one 20 amp dedicated line for the front end. This, in my opinion, is just right, or maybe a little overkill.
Even one dedicated line is the most cost effective upgrade I ever made. |
I like the idea of dedicated lines with dedicated neutrals and isolated ground if possible.Use IG recptacles. If you don't have enough breaker space add a sub panel close to the gear. SDcambell's lay out sounded like it would be a good place to start. Go with 20 amp circuits. Up grading to a # 10 wire is fine though I personally find that a little extreme on runs less then 150'. But what do I know I'm just an electrician not an engineer. |
The fewer the number of lines, the less risk you run producing ground differentials and loops which may induce hum into your system. My two channel audio system performs best on a single circuit. |
Try one heavy line for high current analog. One smaller line for all other analog. One line for digital + TV. Temporarily install them lying across the floor, then listen & experiment. Try adding more lines if you really feel the need & see if you hear differences. Experiment with directionality; some report that one way betters the other. Be sure to allow adequate time for conductor breakin.
I ran my own single dedicated line: three strands - the usual black, white & green (with some advice from Mike VansEvers) using #10 solid copper THHN. Line them up straight, & tape the ends all together. Put that combo into your power drill chuck & fasten the other loose ends tight in a vice. Now spin the whole bundle slowly until tight like a spring. It will unwind a lot when you power off the drill. Exchange ends & finish the twist. Run this bundle from the fusebox to a dedicated outlet. BTW: a 20A ceramic fuse sounded much warmer & smoother than the glass fuse. Regarding directionality: you just look at the printing on the wire's insulation & ensure that all 3 conductors are aligned identically. One direction may sound better than the opposite direction - you can try running the bundle either way (installing it temporarily of course). Re: the twisted conductors - this relates to something about the magnetic flux fields canceling each other. You'll find that some upgrade AC cords are made this way too.
Of course you must run this twisted wire bundle in a conduit (or in 3/8" Greenfield if code permits - much easier to work with). Regarding surge protection & filtering: I have a big Joslyn gas-discharge primary arrestor, across the whole house' primary, in the basement. Then a G.E. MOV (metal oxide varistor) in parallel across my Wattgate 381 outlet (mounted in a box) upstairs. MOV's are not supposed to degrade the sound; Chang Lightspeed uses them internally for transient protection. I also use two Chang Lightspeeds (a 3200 and a 9900 Amp) in addition to some pretty seriously expensive upgrade AC cords. The dedicated line sounded even better with the Chang's than it did standalone.
I'm gleefully satisfied with the results so far. Dramatic improvements over the house wiring! I polished the ceramic fuse clean & bright with crocus cloth, then applied Kontact. Same with the #10 solid conductors' ends, just like I do with all my AC cables. If you use anything larger than #10 it becomes a bear to work with. #10 is stiff too, but at least it's still workable. Also consider isolated grounding. |
You might think about this from the standpoint of how many components in your system draw large amounts of current. For example, if you have two power amps that both draw significant current, you might want to have a dedicated line for each of them. Your TV also draws a fair amount of power, so maybe a dedicated line makes sense there also. If you have 1-2 large subs, they might also warrant a dedicated line they could share. The final remaining component that might also merit a dedicated line is your preamp/processor. Although the pre/pro draws a relatively small amount of power, you may want to insure that it has its own source of clean power, given that it feeds the rest of the downstream system. Other components that draw relatively small amounts of power, such as a DVD player, VCR, etc., could be lumped together onto one line. Counting up, then:
1 line for each power amp
1 line for the TV
1 line for the subs
1 line for the pre/pro
1-2 lines for everything else
I have to say that 6 lines may overkill, unless you live in area with very bad electrical power. However, it should ensure that you have lots of available, clean power to the components that need it most. |
