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About bkolfo4

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  • Birthday 10/24/1969

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    Denton, TX

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  1. Is the -7.5 dB track the recommended track for gain setting. Seems like a low gain track for setting gain.
  2. I just replied to your email again - my mistake. I thought you said SP3. SP4 should handle that amp no problem.
  3. What happens when you play a frequency where the impedance is not high? You do understand that a sub is not just "1 ohm" and becomes 3 ohms when put in a box? I am not trying to be a smart ass, but many people have no clue that this is not what is happening. There are frequencies where the impedance can approach DCR. That being said, with subs it will more than likely be above the crossover frequency, but it will really depend on the driver, enclosure, and the XO frequency the user uses. Impedance is also at a minimum at port tuning, coupled with excursion being at a minimum. More power, less cooling. . . But once again, everyone still misses the fact that the output plot does NOT follow the impedance plot. It is really irrelevant for a daily musical system. And a driver that can handle 4000 watts can still perform awesome with only 2k watts. I have a guy here that was running a UFO BTL and swapped for a SP4. With only 2500 watts, the SP4 killed the UFO below 35 Hz.
  4. It is not there at all frequencies. It is there even when the sub is out of the box. At the peak "rise" (Fs), the output is not at a low. Hint: The output doesn't follow this "rise" everyone worries about. Making decisions based on "rise" is not the best idea unless you are building a burping one note wonder. When you actually understand that "rise" doesn't matter, let me know. and a little extra - being able to take a sub to the limits doesn't always make it the best choice. While the peak output may in fact be higher for sub A, sub B might be way louder at lower frequencies making it a better choice a particular application.
  5. When will people ever get off impedance rise??? Crap.
  6. They are both great drivers. The BTL definitely has the ability to be louder at or below its max power if you are looking for a score on a meter, but the SP4 is a low frequency monster. Your dip is only 3 dB. It is just how that driver reacts in the box you have it modeled in. Not uncommon, and in a vehicle will more than likely unnoticeable.
  7. I ran them free air in Astro doors. 6 per door, 115 watts per driver. Midbass was like a hammer hitting my leg. . . Really clean sounding mid, not a PA speaker.
  8. I run them without a HP crossover in my home speaker designs. Boxes normally tuned to 35 Hz. Work great. https://youtu.be/jg2Gafx1mNs
  9. The box you are calculating is ideal for a home sub. In a car, smaller boxes with tuning in the low to mid 30's work great.
  10. Man these look nice. Think I have seen that pic you posted of them. . . Not sure why there would be an issue with the old ones and lower bass. Maybe door is flexing too much or not enough power? I ran 100+ watts RMS to each of mine in my van down to 57 Hz (that was the amp setting) and they did great. Have 8 of them in my garage right now - just under 4 cuft enclosure for 4 of them, tuned to 38 Hz. Plays down to 35 Hz loud and clean with 75 RMS to each driver. Will be testing soft parts soon to see if new soft parts can be used to recone old AA drivers. Brian
  11. I built my older mustang box in 2 pieces. Put it together in the trunk. Just finished a 2012 mustang box that is 3 pieces assembled in the trunk. 5.2 cuft.
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