3 way speakers build question

[68kaiser]

I want to build a set of 3 way speakers. I have been researching crossovers, box designs, roll off and everything else but can not find a answer for this question.

In a three way set up say you have 100 watts RMS and 3db headroom for 200 watts @ peak. How much of those watts go to bass/mid/high? Do I need a tweeter and a mid that can handle the full 100 watts each? I no the woofer takes most of the abuse but how much to all three?

 

[westend]

Typically, the woofer will be using most of the watts delivered. This is the reason that many speakers have L-pads, to attenuate the power delivered to the tweeter or smaller midrange driver. You do not need a tweeter and mid that is rated at the same wattage as the woofer.

In a perfect world, the three drivers would have equal power handling and sensitivity so output would be somewhat equal through the BW of all the drivers. This is never the case, though, because the individual drivers have rising impedance as to the frequencies that are reproduced. Adding to the complexity is that the crossover components are diminishing the amount of power to the drivers.

As a speaker designer, you would probably wish to use drivers that are as equal in sensitivity and impedance as practical, disregarding the power handling as the overall speaker system will be derated as to the highest power handling of the most efficient driver, usually the tweeter (and it's combined network components).

Hope this helps.

 

[Dr_Jekyl]

Power that will be distributed among the speakers will be determined according to each speakers impedance (resistance). When crossovers are used total impedance must be determined by consideration of additional components such as capacitors & inductors in circuit. The formulas that are used to calculate these are some-what complicated & unfortunately I dont know how to write them correctly using this keyboard due to the fact that there are NO charactors availabe for the squared & square root symbol. If only speakers were used (no crossovers), calculating actual power consumtion of each speaker can be done using the resistance or ohm value of each speaker in the enclosure. The following formulas are used to do this: When Connected in SERIES; R1 + R2 = Rt. When connected in Parallel; Square Root of...... R1 + R2/R1 - R2 = Rt (R = Resistance/ohms, Rt = Total Resistance/ohms). Once Total resistance is calcuated for each branch in circuit.... Power consumtion for each speaker can be determined using the following formula: R1 + R2 = Pt (R = Resistance/ohms, P = Power/watts, Pt = Total Power/watts) When crossovers with capacitors and inductors are added........ power consumtion gets a little more difficult to calculate due to the fact that capacitor resistance has to be determined ( Xc = capacitor impedance/ohms) & Inductor resistance has to be determined ( Xl = Inductor impedance/ohms) before actual power consumtion of each indivigual speaker can be calculated. Should you require these more comlex formulas please let me know and I'll send them to you. If you are NOT familier with algebra..... you'll have to give me the schematic diagram with component values (resistance, farreds, henries) & i'll calculate the power drops of each item for you. Hope this helps... GOOD LUCK!

 

[68kaiser]

thanks for the information that was perfect.

 

[LQ1Z34]

The actual answer is you can't really know what the 'power handling' is, since your source will determine what frequencies will be reproduced, and with what intensity. Practically speaking though, it will be dependent on the woofer xmax and thermal power handling. Mids and tweeters tend to get blown up from clipped signals less than truly overpowering them, unless you cross them over too close to there resonant frequency.