Audio Crossover Frequency Equation....

AI Thread Summary
The discussion centers on verifying an equation for calculating crossover frequencies in a three-tier sound system. The user aims to achieve an optimal sound by splitting frequencies among bass, mid, and top speakers, using a logarithmic equation and specific roll-off rates. The chosen frequencies are based on the operational ranges of the speakers, with considerations for signal boosting and attenuation at crossover points. The user expresses uncertainty about the accuracy of their calculations and seeks clarification on their approach. The goal is to ensure a flat frequency response for improved sound quality across different sound systems.
Gary Trinder
Messages
2
Reaction score
0
Can anyone verify or correct this equation to work out the crossover frequencies of a three tier sound system please? I never was the best in my physics classes...

(Please find attached "Crossover Freq.dpf")

And thank you in advance for your time.
Sorry about the way i have had to write it.Many thanks,Craft
 

Attachments

  • Crossover Freq.pdf
    Crossover Freq.pdf
    22.3 KB · Views: 332
  • Crossover example.jpg
    Crossover example.jpg
    29.9 KB · Views: 546
  • Crossover example workings out.jpg
    Crossover example workings out.jpg
    30.6 KB · Views: 545
Last edited:
Engineering news on Phys.org
I have no idea what you are doing. Why are you choosing those frequencies, and what is the point of your calculations? I'm totally missing something.
 
Sorry, its hard to write in one foul swoop without getting too confusing.
To set the scene: This is all in a free field environment (no variables) and I'm only picking these frequencies in particular so i can do the equation now and know i am correct.

This is so i can just apply the equation with the correct frequencies on every different sound system that i use giving the best sound out of the speakers. (Just to add, I will also be taking the room into consideration after this process and not at this point).

My objective is to split three tiers of speakers equality using a logarithmic (Log10) equation.
The reason i have chosen these frequencies is because i know:
- The bass drivers (speakers) go as low as 30Hz, in turn i want to roll off at a 24Db per octave slope. Thus choosing 35Hz as a rough estimate.
- The tops (top speakers) go as high as 19000Hz and again i roll off at a 24Db per oct.
- In between these two sets of speakers is a middle layer of speakers (mids) that overlap (frequency wise) both the tops and bass.

When the speakers overlap it boosts the signal by 3Db so the idea is that i create the most flat frequency response from all the speakers combined by crossing the frequencies over at the value worked out by the equation i added before. Also at the point of crossover a -3Db attenuation is added to remove the unwanted boost.

I'm not 100% sure i got the equation correct though, my maths and algebra skills are not the best. ;)

I was always told in university that this was the correct way to get the least stress out of the speakers and the cleanest sound.

Thanks for taking the time to read this, its greatly appreciated.

Gary

Ps Attached is a picture of the sort of sound systems i am currently using.
 

Attachments

  • Ligwa.jpg
    Ligwa.jpg
    40.7 KB · Views: 513
Very basic question. Consider a 3-terminal device with terminals say A,B,C. Kirchhoff Current Law (KCL) and Kirchhoff Voltage Law (KVL) establish two relationships between the 3 currents entering the terminals and the 3 terminal's voltage pairs respectively. So we have 2 equations in 6 unknowns. To proceed further we need two more (independent) equations in order to solve the circuit the 3-terminal device is connected to (basically one treats such a device as an unbalanced two-port...
suppose you have two capacitors with a 0.1 Farad value and 12 VDC rating. label these as A and B. label the terminals of each as 1 and 2. you also have a voltmeter with a 40 volt linear range for DC. you also have a 9 volt DC power supply fed by mains. you charge each capacitor to 9 volts with terminal 1 being - (negative) and terminal 2 being + (positive). you connect the voltmeter to terminal A2 and to terminal B1. does it read any voltage? can - of one capacitor discharge + of the...
Back
Top