Bronze Member Username: Yamahabanshee1Cincinnati, Ohio USA Post Number: 49 Registered: Jul-04 | What will thump harder 2 12" Visonik V812D2 subs and 2 2400watt amps or 2 12" Fusion Power Plants and a 1600watt amp? I know that the Fusion's will be louder because the sensitivity on the Visonik's is 84dB and the Fusions is 93dB! |
Silver Member Username: JmloughreyFarmington, CT Post Number: 553 Registered: Jul-04 | depends alot more on Xmax of the subs, true power outputs on the amps, box, and cabin gain will all play a major role in it... |
Gold Member Username: Its_bacon12Hfl, Ny Usa Post Number: 1185 Registered: Dec-03 | theres no way u can tell how loud a sub will get by looking at sensativity... one 13w7 can hit 147 ish and it has a sensativity of 84 i think |
Silver Member Username: Koz1031Monticello, In United states Post Number: 332 Registered: Jul-04 | thank you for partially clearing that up for me bacon. I've always wondered what the sensitivity rating was for. That is something I've always wondered and was to lazy to research. |
Gold Member Username: GlasswolfNorthWest, Michigan USA Post Number: 6547 Registered: Dec-03 | koz, all ya had to do was ask. Speaker Sensitivity and Efficiency. Speaker sensitivity is a specification provided by all manufacturers of high-quality speakers. The sensitivity rating has no relation to sound quality, as some of the very best speakers have low ratings. Sensitivity ratings simply tell you how much sound a speaker will produce for a given power input. Sensitivity ratings are given in decibels per watt at one meter, or db/Wm. So, with an input of one watt (usually white noise), a speaker with a sensitivity of 90 db/Wm will produce 90 decibels of sound at a distance of one meter. A sensitivity of 90 is considered average, with ratings of 87 and below considered low sensitivity and above 93 considered high sensitivity. To increase the volume by 3 db, you must double the power. So, using the example above, to make 93 db you would need two watts, and to make 96 decibels, four watts. Most of the time your system is cruising along producing only a few watts. You need extra power for loud bass passages, crescendos in classical music, and other highly dynamic passages. Your speakers may need more than 10 times the average power to re-create these dynamic passages accurately, and if you are playing loudly to begin with, you may need an awful lot of power if you have speakers with a low sensitivity rating. So, when you are buying an amplifier, consider your speakers, your vehicle size and how loudly you want to play. If you have sensitive speakers, you probably will not need as much power -- even 20 clean watts would probably be enough. If your speakers are only moderately sensitive, your vehicle is large or exceptionally noisy at highway speeds and you want to play loudly, you will need more power in order to faithfully reproduce dynamic passages. "Sensitivity," which is expressed in dB, should not be confused with "efficiency" that is expressed as a percentage of power out relative to power in. Efficiency data for loudspeakers suffers from many problems such as failure to consider variations in frequency response. Speaker efficiency is the ability of the speaker to do work or use power. The more efficient the speaker; the less power is required for the speaker to produce sound. Voice coil design, type and size of the magnets, speaker cone design and material, speaker size, etc. all play a critical role in determining speaker efficiency. However, speaker size is a good general method for guessing efficiency. Typical speaker efficiency (for physicists) is about 5%. Meaning that for 100% power input, you get about 5% acoustical work back. Keep in mind that when considering subwoofers, or any speaker that will get more than ~100 watts RMS of power, these measurements are affected by other factors that make this specification less than useful when choosing between speakers. from http://www.wickedcases.com/caraudio/ampspecs.html |
Gold Member Username: GlasswolfNorthWest, Michigan USA Post Number: 6548 Registered: Dec-03 | "2 12" Visonik V812D2 subs and 2 2400watt amps" firstly, visonik sucks, so I wouldn't expect much regardless of power applied from that system. Secondly, two "2400 watt" amps? Are you talking RMS or peak power? If you mean peak power, then the RMS is more like 100 watts at best, which is piddly. If you mean RMS, that's 4800 watts of power from what could only be a pair of class D amplifiers unless you spent over five grand for amps from Zapco, US Amps, or similar companies who have class AB amps in that range of power. So, assuming this, you're talking close to 500A of current draw. I hope you can either a: plug that car into a 220VAC line outlet, or b: happen to have at least 3 dedicated alternators in that car and a bank of deep cycle batteries to supply the required current to power that setup. Otherwise, you're dreaming if you think you'll get almost 5Kw of power from a car system. "2 12" Fusion Power Plants and a 1600watt amp?" more cheap subs, so probably another cheap peak power rated amplifier. But, on the off chance that it's really 1600 watts, that's about 160A of current draw, which means a minimum of a 200A alternator to handle the demands of the amplifier, and 1/0ga power cable to the amplifier. what sort of cars are these? how much sound deadening in each one? what is the rest of the system for each car? how are the charging systems set up? what are the enclosure specs for each setup for the subs? we need to know all of this before we can even begin to speculate on comparing them. |