CA&E: What's the difference between adding a large capacitor inline with the power supply and that energy being stored in capacitors within the amplifier? Couldn't the same results be achieved?
AD: The difference is huge! The equation for energy is 1/2 times C times V2. We can see by the equation that the voltage term is SQUARED, making it the most powerful part of the equation. It is difficult to store large amounts of energy with only 12 volts. More importantly, by having the energy stored on the other side of the amplifier's power supply, the amplifier can control the energy coming in and out of the capacitors as in how much and when. By doing this, we are able to achieve "current-averaging," whereby the amount of current that comes from the vehicle's electrical system can be averaged over time. By averaging the current over time, the power losses in the power cables from battery to amplifier and within the amplifier's power supply are greatly reduced. Traditional amplifiers work like this: When the bass line hits, the energy that feeds the speakers is more or less coming straight from the vehicle's electrical system. No matter how big the amplifier is, if the vehicle cannot deliver the power, neither will the amplifier. The hybrid technology in the T15kW works like this: When the bass line hits, that energy comes from the AMPLIFIER. At a more convenient time, like after the bass line, the energy can go from the vehicle, back to the amplifier. By doing this we have an amplifier that can deliver MORE power than the vehicle can supply for periods of time. Since music is very dynamic in nature, having relatively loud and quiet periods, the T15kW can play music continuously in this manner. Putting capacitors inline with a traditional amplifier will not produce the same results.
CA&E: Is there a set limitation for current draw from the vehicle's electrical system predetermined by the amp? Does this equate to a percentage of its maximum current consumption?
AD: Yes and yes. The amplifier has a very sophisticated power supply that sets this limit. In the T15kW, that limit is set to approximately 350 amps. This value was chosen based on average modern music containing around one fifth of the amount of power of a continuous sine wave.
CA&E: Are there any hurdles with the technology that need to be overcome before hybrid amps become part of the Rockford Fosgate lineup?
AD: One of Rockford's biggest challenges is not with the technology itself but rather educating our customers on the benefits of the technology. The primary focus of the T15kW is to demonstrate and promote this technology. Without hybrid technology, a stack of traditional amplifiers as powerful as the T15kW would not be possible to use in a vehicle without doing very extensive electrical system upgrades. Once this technology is understood, it will be easier for Rockford to introduce products containing the technology into the marketplace.
CA&E: When should we start seeing this technology trickle down into more affordable, mainstream amplifiers?
AD: Rockford is very excited about putting this technology into more affordable mainstream amplifiers. We are currently in the development process of doing so. We hope to introduce something as soon as CES 2008 or before.
CA&E: With smaller amplifiers drawing minimal amounts of current, at what power level does this technology start to make sense, both in terms of performance and cost?
AD: That really depends on what the "acceptable" amount of current consumption is. For aftermarket systems it may around the 1,000-watt level. If it were for an OEM customer, however, they may like to see a 200-watt amplifier that only requires six amps. Typically, the technology will reduce the peak current to one fifth that of a traditional amplifier. I should also mention that the technology has to do with the power supply portion of an amplifier and not its output section topology; thus, it could be used in Class A/B, B/D, D, etc., platforms.
CA&E: Will amplifier size ever be an issue with this technology? Are there any other limitations?
AD: The capacitors used are a new technology for the capacitor manufacturer as well. The applications they were used in before the hybrid amplifier were not as size sensitive as car audio is. We are working with the capacitor manufacturer on development of devices that have form factors better suited for use in mobile amplifiers. The size-per-watt of the amplifier shouldn't change much due to the technology. As an example: The T15kW is no doubt a huge amplifier, but an equivalent stack of amplifiers and batteries to do the same job isn't any smaller.
CA&E:K How were you chosen to take this idea and bring it to life?
AD: It started with me on the quest for more power on my own time. Luckily for me, I work for a company that is a leader in the industry and is always working to stay on top. As such, research and development exercises like this are always in the works. Sometimes they don't work out, but sometimes you end up with something killer! Such as the 3Sixty.