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About alex912005

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  1. UPGRADE TIME!!! Gonna have to re-upload all the old pics. Something happened to them.
  2. alex912005

    Are most of us actually under powering our sub's?

    That's when you find out the sad truth, that they can't take their rated power. Or that they can take it for 2 minutes before the coil smells.
  3. You can create test tones in Audacity but keep in mind that this software shows 0 dB as +6.2 dB. If you want -5 dB you need to make them +1.2 dB in Audacity.
  4. It's more future proof to get the biggest one available for your engine. I got a 270A and I'm sorry I didn't get the 370A.
  5. alex912005

    How to clamp for power and find impedance rise

    Clamp testing is the way to calculate your amplifiers true output power and the actual impedance being driven, in it’s real environment. Clamp testing, and understanding the numbers it gives, is a must if competing in SPL or interested in getting more performance out of any system. How to Calculate Amp Power and Impedance: You will need a Digital Multi-Meter, AC Amp/Clamp Meter and Test Tones/Signal The Volt-meter/Multi-meter test leads should go directly to the speaker leads from the amplifier. Pick a (-) and (+) to pierce your test leads into. Set your Volt-meter/Multi-meter to AC Voltage and turn on the Peak Voltage feature. The Ampmeter/Clamp-meter should be clamped around only the (+) speaker wire coming from the amplifier outputs. Set the clamp meter to AC Amperage. Turn on the Peak Hold feature. Do not use the test leads of the Ammeter/Clamp-meter in this process. When testing the system for output power and impedance at one specific frequency, test using that single frequency. To know the impedance curve and power curve, test tones from 70Hz down to 20Hz in 5Hz increments. If you don’t have a way of generating tones from 70Hz down to 20Hz, you can download the wav files we have created. 70Hz-20Hz ( in 5Hz increments) If power and impedance numbers for a daily driving system are needed, we suggest warming up the subs and amp to get readings congruent with how the system is normally played, SPL competitors should take readings with coils/amps at room temperature. Roll up the volume at the head unit that is just under clipping indication on the amplifier. The Voltage and Amperage numbers are simply multiplied together to get your Wattage. (P=VI or Power equals Voltage times Amperage). To find out what impedance the amplifier is seeing, simply divide the Voltage by the Amperage. (R=V/I or Resistance equals Voltage divided by Amperage). To plot a power or impedance curve, repeat the previous test for each frequency, i.e. 70, 65, 60, 55, 50Hz etc. The commonly used term “Box Rise” is the sum of the subwoofer(s) impedance and the additional acoustic impedance added by the enclosure and the vehicle. For example, 4 subs wired to a 1.0 ohm load, after running an actual impedance curve, may present a load over 4 Ohms to the amplifier. That 1000w amplifier may be pushing between 200w and 400w of real power. An informative experiment would be to test the box in its normal position, then change the position in the trunk or cargo area. Try moving the port and speaker about 2″ away from boundaries in the cargo area and test it again. The numbers will come out different due to changing acoustic load presented by the new location, affecting the SQ and SPL of your system. For an Ohm’s Law Calculator and other useful tools, try the follwing link. *From DD Audio website.
  6. Just connect lugs to each end and connect a fuse holder between them. You need to have fuses anyway. Or a distribution block.
  7. alex912005

    Wire size for subwoofer

    The thicker the better.
  8. Don't think that's possible. Your number of coils has to be a multiple of your number of amps. You have 8 coils and 3 amps. If you had 12 coils, or 6 coils it would have worked. Either run only 2 of the 7500s or get another one and run 4, or 4 5500s
  9. alex912005

    Looking for song title.

    So where can I get that version? Can you send me a link?
  10. alex912005

    Looking for song title.

    What is the second song?
  11. Example: "All cars are louder with a door open, with a window open or even 2 open. I think it's because when it's all sealed up with everything closed, the subwoofers are somewhat under pressure, limiting their movement. When you open a door, suddenly the subs are under less pressure and can move more, making them a little louder. There's also that thing called "the hot seat", when the car is all sealed up on the passenger side with the door open on the driver's side. This way the passenger (victim) feels a lot higher dBs than the driver, making him jump out the car like the seat was hot. There are cars that do 160 dB all sealed up on the dash, but if you open a door and meter in the kick, the score goes up 3 dBs or more, the equivalent of double the RMS. There's also this EXO video where JP's girlfriend broke Scott Bowman's golden rule, which is to never open the door at max volume, because the sudden change in pressure could make the subwoofers bottom out or unload, which would damage them." Quote from this topic:
  12. I platinumed it on PS4. Good game. I've also played Heavy Rain and Beyond Two Souls made by the same company (lead by David Cage). Also piewdiepie is currently doing a Let's Play on this game. He was forced by the fans. But don't watch it if you don't want spoilers.
  13. Not necessarily. The alternator does charge the battery because that's why it's in the car. The battery's job is to provide enough power to start the car, and the alternator's job is to provide power to the vehicle when the engine is on, and also charge the battery so that you can start your engine next time. So it does somewhat charge the battery, but a charger can do it too. You can buy a small Ctek charger like this one: CTEK MXS 5.0 Also alternators don't make max power if there isn't a huge draw.