crossover

jancopanco

Member
2013-02-05 10:06 am
I would like to do the speakers for amplifier 60W RMS / 8 ohm. I watched the speakers Woofer Beyma 8BR40/N - 50W RMS, 35 - 6000 Hz, 90 dB, 8 ohm or 8BR40N - 50W RMS, 35 - 6000 Hz, 90dB, 8 ohm ( whitc is better ) and Tweeter Beyma T2030 - 15W RMS, 1,5 - 20KHz, 95 dB, 8 ohm with crossover Beyma V2 hifi, 300 W, freq 3 KHz, 8ohm.
I already have a box dim: H-450, W-300, D-320 mm

I turn to you, because I'm not so sure that this is a good relationship and frequency of cutting 3 KHz correct

Would it be better if I would use stronger tweeter and would cut the freq to 4 or 5 KHz
.
Does anybody can help me with advice and calculation for crossover

Best regards

Thank you for directing
 

jancopanco

Member
2013-02-05 10:06 am
I do this for my friend who have restaurant in a rustic style. I made him amplifier 6x60W RMS, 8 ohm for six rooms.
Now I need speakers for normal volume and sometimes for special meeting a little louder - stereo in one room.. I m a little afraid that is the tweeter for a little louder weak. If I take tweeter Beyma CP21F I have to make crossover because the frequency is higher. If you thing that the first combination is OK I will not complicate
 

jancopanco

Member
2013-02-05 10:06 am
Hello to everyone,
If anyone can tell me at least how to adjust the tweeter which has 15 dB higher sensitivity than woofers. Which resistors I need and how they tie - Beyma 8BR40N and CP21F. Cutting frequency is 4700 Hz. I hope I have correctly calculated ( 3u F / 0,38 mH )
 
The Beyma woofer works well in your cabinet (assuming a closed box), but it has a severe cone breakup at 2 kHz and is difficult to use in a 2-way speaker:

http://profesional.beyma.com/pdf/8BR40NE.pdf

This means the woofer should be crossed below 2 kHz and you have to find a tweeter capable to operate from 1.5 kHz. That's not easy, do you only consider Beyma or other brands as well? Maybe a 30 mm dome or a horn will do.
 

jancopanco

Member
2013-02-05 10:06 am
First step:
If I take Beyma BF8R - 50W rms/8 ohm, Beyma T2030 - 15W rms/8ohm and crossover Beyma V2 hifi with frequency 3 KHz, will be this combination OK - because tweeter has only 15 W rms ( amp has app 60W rms and I think that it will be mostly on max 20W except in extreme situations could be louder )