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  • #16
    Originally posted by Evan
    It depends on your ears, wallet and gullibility. Also, the Chinese are masters of product adulteration. The sellers of the product here are making a virtue of a defect. As is usual in the audio business, it's all BS.

    I hear ya!
    Location: Saskatoon, Saskatchewan, Canada

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    • #17
      Yeah, with that you can only use 10 inch speakers, since a 1 inch would be too small, and a 100, 101, or 111 inch speaker is not made. And while you're at it, you must carefully measure the length of the wire, and cut it into precise multiples of centimeters. Failure to do so will allow some of the digital signal to cancel out before it reaches the speaker. And here's another little known fact, except in performance car audio circles- when installing power wires for the amplifiers, you should take care to have the information printed on the wires leading away from the battery. This gets more of the power from the battery leading towards the amps, and less is reflected back to the battery.

      If you're going to take this much care with your installation, there's one more thing to keep in mind- the power wires should never pass within three inches of the seat bolts, as a magnetic interaction will cause a low voltage null to travel down the wire. When that reaches the amps, it will cause a current ripple. The effect of that is to force the amps to traverse through two modes of operation- one is isoplanar, and the other is epitonal. In either mode the amps sound fine, but when it's traversing the two modes there will be an audible distortion in the output. The effect can be lessened by adding a pass-through terminator to each power wire, and these terminators, if close together, must be oriented at right angles to each other and mounted on polynytefton blocks to prevent interaction with the body metal.

      Trunk liner, if used, must be grain-oriented in the direction of the length of the vehicle for best results.
      I seldom do anything within the scope of logical reason and calculated cost/benefit, etc- I'm following my passion-

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      • #18
        Here is a good example of severe BS being slopped about.


        Q.) A customer asked what eutectic brass is? Doesn't eutectic have to deal with the melting point of the metal and that this is a low melting point material? He also stated "From everything I have read they tend to identify brass as a fairly poor conductor indicating that only 28-30% of the signal is being transferred." While I would tend to agree with this statement, I can not dispute that your connectors sound the best out of all I have used with Solid Core Silver. The best connector is no connector, but since hard wiring is usually out of the Question, if I had to choose, I would say I like yours the best. Why did Cardas decide on Brass over Copper for the connectors? I know it is easier to machine. Brass is 70% copper 30% Zinc, correct? - Drew

        A.) The decision to go with this brass alloy was made because it sounded best of all the materials we tried. The basic reason is it eliminates all the thick conductors in the connector. Thick conductors in connectors, like in cable, cause a ring. The conductive path in the connector becomes the silver plating which is similar in character to the conductors in a good cable. The brass material was selected because it is a low permeability, high resistance conductor and because it machines well. We tried many metals in the beginning. Most did not compare well to this alloy. Other alloys that fared well were beryllium bronze and beryllium copper. Pure copper and aluminum did not work well to my ears. - George
        http://www.cardas.com/content.php?ar...gestring=Cable
        Free software for calculating bolt circles and similar: Click Here

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        • #19
          A "wire" consists of several components in a system....

          1) the "head end" connector, and its conntact to the source

          2) the connection of the wire to the connector

          3) the wire

          4) the connection of the wire to the "load end" connector

          5) the load end connector and its contact to the load

          How and where are you measuring this "drop"?

          Are you including ONLY the wire, or is at least one of the other "parts" included?

          Have you tried checking the drop on the connectors?

          As for the wire.... (usually "cable" if made of many "wires")

          Stranded wire will be larger diameter than solid wire. There are air spaces between the strands, so the OD must be larger for the same cross-section of conductor.

          Some braided cables, Litz and some types of high flex, are very loose, and have a MUCH larger diameter for the same actual conductor cross-section. This is due to the way the wires are "laid" in the cable.

          Is this #8 wire LABELED as that, or is it simply the same diameter as #8? Any stranded wire will not measure right on a wire gage intended for solid wire. And of course, labels are only as good as the honesty of the labeler.
          CNC machines only go through the motions

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          • #20
            A lot of BS in the car stereo industry. That's for sure. But if they were serious, we wouldn't have anything to make fun of, or have to listen to the Booma-da-booma-da-boom-boom as the local "hat-on-backward" crowd drives by.

            I saw a car in the shop the other day that had an enormous stereo installed. It must have been a professional food service industry installation because all of the cabling was made with that new magical Chinese "lamp cord", wire nuts, and at least 200 yards of heat shrinkable electrical tape. They also went with common practice to prevent resonance by not using any fuses.
            The car was in the shop because the installer neglected to tighten the alternator mounting bolts and fried his $1700 engine management computer.
            The poor kid had to sell his sub-woofers to help pay for the repair....
            No good deed goes unpunished.

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            • #21
              It is not speaker wire, it is intended for hooking amps up:

              http://audiopipe.com/products/cables...ps-cables.html

              It appears to be real 8 ga stranded wire, I have used a lot of it in SO cable form for wiring welders and stuff.

              The voltage drop is entirely in the wire. I have measured between the connector to make sure there was none in the connectors. I am using the Molex Mini-Fit SR connectors, good for up to 50 amps. Lame video, really good connector:



              I also cut down and existing 20 length in half and the voltage drop was cut in half.

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              • #22
                I called up the company that makes the stuff and found out it is copper coated aluminum. Nice... I guess it does not say copper anywhere on the product listing.

                -Jerry

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                • #23
                  Originally posted by macona
                  I called up the company that makes the stuff and found out it is copper coated aluminum. Nice... I guess it does not say copper anywhere on the product listing.

                  -Jerry
                  Ask them if they would like to pay for your car fire lawsuit now, Or later.
                  Play Brutal Nature, Black Moons free to play highly realistic voxel sandbox game.

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                  • #24
                    My old airplane manual says you're right on the money for 25A for 25 feet, (continuous operation for "tin coated copper wire" ) the chart falls right between 10g & 8g wire. Defaulting to the larger wire, you can expect a .5V voltage drop.

                    scroll down to pg 30 of the pdf

                    http://rgl.faa.gov/REGULATORY_AND_GUIDANCE_LIBRARY/RGADVISORYCIRCULAR.NSF/0/99c827db9baac81b86256b4500596c4e/$FILE/Chapter%2011.pdf

                    and if anyone is interested, here is the entire manual: Lots of technical info in here, much of it not just applicable to aircraft.

                    http://rgl.faa.gov/REGULATORY_AND_GU...e?OpenDocument

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                    • #25
                      The electrical code book has wire resistance tables in it. Funny thing about that is that my rather old copy says that the maximum length run on a 15 amp 120 vac branch circuit of 14-2 is limited to 250 feet. If you look up the wire resistance of 14-2 for that length it will produce twice the permitted voltage drop at the maximum load of 12.5 amps on that length of run.

                      Somebody must have forgotten to double the resistance for the return run.
                      Free software for calculating bolt circles and similar: Click Here

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                      • #26
                        Originally posted by Black_Moons
                        Ask them if they would like to pay for your car fire lawsuit now, Or later.

                        Why? if anything it avoids the issues of aluminum oxidation. They didn't specify any particular "ohms per foot". Knowing that it's aluminum, you just use the aluminum tables in the NEC (if it's a rated wire, which it probably isn't unless marked).

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                        • #27
                          Originally posted by lakeside53
                          Why? if anything it avoids the issues of aluminum oxidation. They didn't specify any particular "ohms per foot". Knowing that it's aluminum, you just use the aluminum tables in the NEC (if it's a rated wire, which it probably isn't unless marked).
                          Yes, Knowing... But Who would know if its not marked? Its deceptive and WILL cause fires when someone trys to use it at the assumed rating of copper wire.

                          Aluminum wire is clearly 'non standard' and hence should be marked as its been coated and hence appears to be copper. Failing that im sure theres lot of lawyers waiting to sue in the USA.

                          Who will be liable when said wire DOES cause a fire?
                          Play Brutal Nature, Black Moons free to play highly realistic voxel sandbox game.

                          Comment


                          • #28
                            WILL cause fires if used as copper? I doubt it.

                            Alluminum wire is very common and installed everyday - 8awg and above. With the increases in copper price, its now rare to see larger feeds in copper.

                            Sure, if it's misrepresented, that's a problem; if not, it's up to the user to figure out what to use. Anyone that uses unmarked conductors (rare...) is rolling the dice anyhow - never mind the metalic portion - what is the insulation rated at, temp and voltage?
                            Last edited by lakeside53; 12-12-2011, 09:12 PM.

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                            • #29
                              This is "primary wire" which is intended for 12-24v situations.

                              Aluminum wire would be fine in many situations, it still has the ampacity but the voltage drop is something I can't live with, I could deal with the little bit though copper, but not with this.

                              So I have three options.

                              1. Replace the wire. The ham radio places sell 8ga zip cord for around $1.35 a foot. Pro: Relatively cheap. Con: Im still dealing with voltage drop.

                              2. Use a 13.8v power supply with a higher output. I have three of these lights and the power supplies I am using do not have a trim to adjust the voltage out. All lamps on is about 75 amps. Pro: Allows me to compensate for voltage drop. Con: Expensive. ~$180 shipped

                              3. Use Individual power supplies for each lamp. Pro: No voltage drop, less expensive. Con: Bulky.

                              Got some thinking to do.

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                              • #30
                                4. Double up the wire.

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