Where did you run your power cable?
#16
01-11-2011, 09:57 AM
Sorry sir, not trying to get into an argument about this but that is incorrect. Just because youve done it in the past doesnt make it right. I have been installing for MANY years now and have seen these situations before. And yes, there are large variations in current.... aka the spikes/surges as the amp draws power due to music fluctuations. Yes, I may not have taken it to the nth degree to explain. It works much easier for those not in the know technically.
The current fluctuations required to induce noise into a signal cable are simply not present in the power wire, regardless of variations in amp draw. The element missing is the full swing through 0v and into negative volts, in other words an AC current. Voltage ripple on the + (and -, which means if you are using a chassis ground the entire body of the car) is not AC. If differences in current draw from the amps WERE able to induce noise, it would be in perfect time with the music anyway and would not come through as noise.
If the grounds are different by even slight amounts, it can introduce noise.
And thats not including interference caused by outside sources: power wires,
control boxes
RF interference that may be picked up from the body of the car
Do some research. Don't just go by what they taught you at your MECP course however long ago that was. Some people who actually understand what's going on the EM environment have shed a lot of light on the subject and most of it is free for the gleaning on the web. Knowledge has progressed a long way since the old days of "1F per 1kW, run your RCAs away from your power wire and sealed boxes are the only way to go in a car." Unfortunately there are too many people living by the old myths and blindly spreading them as gospel to let them die.
#17
01-12-2011, 02:20 AM
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I've also been installing for many years, just not "professionally." that said I have yet to actually meet a "professional" installer that understands the technical side of what is actually happening. Not saying that they don't exist, just that I've never met one. Something about them never having studied EE...
The current fluctuations required to induce noise into a signal cable are simply not present in the power wire, regardless of variations in amp draw. The element missing is the full swing through 0v and into negative volts, in other words an AC current. Voltage ripple on the + (and -, which means if you are using a chassis ground the entire body of the car) is not AC. If differences in current draw from the amps WERE able to induce noise, it would be in perfect time with the music anyway and would not come through as noise.
Which would not qualify as "good grounds."
Impossible.
Possible but not likely.
LOL! So you would just run the signal wires...where? And where exactly would this RF interference on the body of the car come from?
Do some research. Don't just go by what they taught you at your MECP course however long ago that was. Some people who actually understand what's going on the EM environment have shed a lot of light on the subject and most of it is free for the gleaning on the web. Knowledge has progressed a long way since the old days of "1F per 1kW, run your RCAs away from your power wire and sealed boxes are the only way to go in a car." Unfortunately there are too many people living by the old myths and blindly spreading them as gospel to let them die.
The current fluctuations required to induce noise into a signal cable are simply not present in the power wire, regardless of variations in amp draw. The element missing is the full swing through 0v and into negative volts, in other words an AC current. Voltage ripple on the + (and -, which means if you are using a chassis ground the entire body of the car) is not AC. If differences in current draw from the amps WERE able to induce noise, it would be in perfect time with the music anyway and would not come through as noise.
Which would not qualify as "good grounds."
Impossible.
Possible but not likely.
LOL! So you would just run the signal wires...where? And where exactly would this RF interference on the body of the car come from?
Do some research. Don't just go by what they taught you at your MECP course however long ago that was. Some people who actually understand what's going on the EM environment have shed a lot of light on the subject and most of it is free for the gleaning on the web. Knowledge has progressed a long way since the old days of "1F per 1kW, run your RCAs away from your power wire and sealed boxes are the only way to go in a car." Unfortunately there are too many people living by the old myths and blindly spreading them as gospel to let them die.
Take an EM sniffer (for lack of a better term atm. Im freakin tired... :o) and run it around the vehicle. (yes, there will be some outside noise....) I guarantee it wont be silent. Ive done it and seen it done.
I dont believe in any 1f per 1kW rule, sealed boxes are necessary depending on the end goal as are ported, bp, IB, etc. And RCA's if at worst case (pending i am wrong... Im dropping it at that.) why even risk there possibly being interference, just run it to the otherside.
#18
01-22-2011, 04:10 AM
To add onto this, just like on a Tv that gets interference with the 3 prong power cable, it is usually due to the outlet that has multiple ground linked together. To avoid this, ground the amplifier to a contact point that has no others possibly tied to it. This is usually due to a faulty ground within the circuit that has alternating signals on the contact point creating creating a voltage swing causing your device to saturate enough to produce noise.
For my amplifier i wired everything thru the grommet on the passenger side located under/behind the glove box (used a pull string and a wire hanger to pull through) then ran both cables on the floor under the plastic next to the door and exited into the carpet under the seat where i grounded the cable to the bolt that attaches the seat to the body. Placed the amp behind the center console at an angle with hinges drilled where the cup holders where because the amp was too large to fit under the seat and i didnt want to mess with taking apart my rear seats.
Hope this helps, if u want pics let me know.
For my amplifier i wired everything thru the grommet on the passenger side located under/behind the glove box (used a pull string and a wire hanger to pull through) then ran both cables on the floor under the plastic next to the door and exited into the carpet under the seat where i grounded the cable to the bolt that attaches the seat to the body. Placed the amp behind the center console at an angle with hinges drilled where the cup holders where because the amp was too large to fit under the seat and i didnt want to mess with taking apart my rear seats.
Hope this helps, if u want pics let me know.
#19
02-19-2011, 08:35 PM
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Why are you guys even arguing about this? Power down the passenger side, RCA's down the driver side, or vice versa. You've got two sides, and a hell of a lot of space in those sills, so why argue about something so pointless?
And to the Pioneer guy: if 19 of your last customers are using Pio gear, I'm assuming you work at Best Buy. More reputable shops do carry some Pio components, but only in the Premier line. To put it another way, if your local Walmart stocks it, you shouldn't be bragging about it.
And to the Pioneer guy: if 19 of your last customers are using Pio gear, I'm assuming you work at Best Buy. More reputable shops do carry some Pio components, but only in the Premier line. To put it another way, if your local Walmart stocks it, you shouldn't be bragging about it.
#20
02-19-2011, 09:27 PM
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And to the Pioneer guy: if 19 of your last customers are using Pio gear, I'm assuming you work at Best Buy. More reputable shops do carry some Pio components, but only in the Premier line. To put it another way, if your local Walmart stocks it, you shouldn't be bragging about it.
Those reputable shops must be sitting on old inventory, seeing as how Pioneer dropped the premier line...
http://www.twice.com/article/388090-...mier_Brand.php
But then again... I have a crummy Pioneer h/u in my truck, and I was an installer at Best Buy, so what do I know...
