x1 measures

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   Please find some real measurements made on an x1 cabinet made of chip board with B&C 18PWB46 inside. 
The box contains no fill at all.
Measurement system: daas 32 bits fft analyser with calibrated mic nearfiled measurement, 95m2 room, not treated at all!

Impedance 6 electric phase
freq from front & rear cone volume (on port)

Hope it might help.
I'l do the box in plywood and measure again...

http://www.labat-camy.com/pictures/speakers/x1_freq_b&c18pwb46.jpg

http://www.labat-camy.com/pictures/speakers/x1_18pwb46_nofill_imp_faz.jpg

Edited by cyranotr - 19 December 2006 at 4:10pm

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cyranotr Members Profile Send Private Message Find Members Posts Add to Buddy List Registered User Joined: 13 December 2006 Location: Turkey Status: Offline Points: 6	Post Options Post Reply Quote cyranotr Report Post Thanks(0) Quote Reply Topic: x1 measures Posted: 19 December 2006 at 3:13am
	Please find some real measurements made on an x1 cabinet made of chip board with B&C 18PWB46 inside. The box contains no fill at all. Measurement system: daas 32 bits fft analyser with calibrated mic nearfiled measurement, 95m2 room, not treated at all! Impedance 6 electric phase freq from front & rear cone volume (on port) Hope it might help. I'l do the box in plywood and measure again... http://www.labat-camy.com/pictures/speakers/x1_freq_b&c18pwb46.jpg http://www.labat-camy.com/pictures/speakers/x1_18pwb46_nofill_imp_faz.jpg Edited by cyranotr - 19 December 2006 at 4:10pm
	Trust your ears...

jeddere Members Profile Send Private Message Find Members Posts Add to Buddy List Registered User Joined: 07 March 2006 Location: Bristol Status: Offline Points: 75	Post Options Post Reply Quote jeddere Report Post Thanks(0) Quote Reply Posted: 19 December 2006 at 4:43pm
	Interesting plots, put that driver into my rough model in Akabak, then drew plots 'measured' from directly at the mouth of each port, then an overall plot: Black Line: Rear Port (mic at port mouth) Blue Line: Front Port (mic at port mouth) Orange line: Mic in between ports, 1m from cab Cab sitting horizontal on the ground. Looks similar to your measurements with the peaks at around 260 Hz. How well does that driver handle the excursion in your box? Edited by jeddere - 19 December 2006 at 5:52pm

cyranotr Members Profile Send Private Message Find Members Posts Add to Buddy List Registered User Joined: 13 December 2006 Location: Turkey Status: Offline Points: 6	Post Options Post Reply Quote cyranotr Report Post Thanks(0) Quote Reply Posted: 20 December 2006 at 3:43pm
	No idea yet as the cabinet has been recentely finsihed but not 'pushed' into hard beats... At some 350 watts it's really excellent sound. but no slamm..only clean low deep extension...but really controled. I cut it at 90Hz (Butterw. 24dB on processor) I tried to match it with a 15inch bass reflex (test purpose). You got so the bass and the slam. I'll do the HD15. That should fit better and louder. I have some doubt about filling the cabinet as shown. I'll never use this bin that high in freq (250Hz). And I don't know wich material can handle 90Hz standing waves at that power...none. I feel it of no use. Driver parameters B&C 18pwb46 (discontinued) : Fs 43Hz Bl : 23Tm Qts : 0,39 Qms : 12,5 Qes : 0,4 Xmax +-5,5 mm vas 156L well 5.5 mm is not the best on market but it is a B&C...sounds good. What does your simulation gives for that driver in the bin? I'm impressed by the very close results you got with your simulation program. Than you very much for your concern.
	Trust your ears...

jeddere Members Profile Send Private Message Find Members Posts Add to Buddy List Registered User Joined: 07 March 2006 Location: Bristol Status: Offline Points: 75	Post Options Post Reply Quote jeddere Report Post Thanks(0) Quote Reply Posted: 22 December 2006 at 7:11pm
	Here's two plots of the excursion: Both at 295 W, Black line: no filter, Orange line: 4th order Butterworth highpass at 30 Hz Blue line: 4th order Linkwitz-Riley highpass at 30 Hz My model has been predicting slightly more excursion than WinISD (about 1mm) though. At least in the X1 you can feel how far the driver is moving! Only use mine up to 80 or 90 Hz too, was just happy that the model had predicted similar resonances at higher frequencies when compared to real measurements. Have fun!

cyranotr Members Profile Send Private Message Find Members Posts Add to Buddy List Registered User Joined: 13 December 2006 Location: Turkey Status: Offline Points: 6	Post Options Post Reply Quote cyranotr Report Post Thanks(0) Quote Reply Posted: 23 December 2006 at 3:18pm
	Thank you very much. I'll protect the driver accordingly. I'm still amazed by the simulation being SOCLOSE to real measuremts. May I ask if your model might predict something about No fill/ with fill cabinet's behavior? I always have problem to align properly my own design (ıt never fits the model)= I build a lot of box to goes to trash! I'm really willing to purchase a good software for Bass reflex, bandpass transmission line design. Any idea? Have a nice day
	Trust your ears...