crossover and eq settings help

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   Wondering if somebody with good knowledge of setting system eq and crossover slopes would be able to shed some light on the effects and reasoning behind some settings i have been given by a manufacturer.
They are for a 2 way bi amp dual 12" plus bms4590 compression.

Dual 12s have high pass 71.5hz 24db lr.
                     low pass 908hz 24db lr
peq1  -7.1db at 1.92k with Q of 6.
peq2 +7.1db at 154hz low shelf

compression driver has high pass 1.36k 24db butterworth and polarity inverted.

peq1  -6.5db at 3k  q of 2
peq2  -2.6db at 1.5k q of 1
peq3  -2.6db at 6.47k q of 5
peq4  -7.1db at 3.17k q of 30   (is q of 30 a misprint or meaning something else?)

compression driver has passive crossover at 6.3k

Although these settings sound ok, i still think there is something missing from the sound wether that be a phasing issue or eq. But without smaarting the system i dont know. So can anyone tell me the reasoning behind what i think are strange eqs and crossover points.

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jamie-ashton-solo Members Profile Send Private Message Find Members Posts Add to Buddy List Young Croc Joined: 26 January 2009 Location: staffordshire Status: Offline Points: 728	Post Options Post Reply Quote jamie-ashton-solo Report Post Thanks(0) Quote Reply Topic: crossover and eq settings help Posted: 07 September 2018 at 6:19pm
	Wondering if somebody with good knowledge of setting system eq and crossover slopes would be able to shed some light on the effects and reasoning behind some settings i have been given by a manufacturer. They are for a 2 way bi amp dual 12" plus bms4590 compression. Dual 12s have high pass 71.5hz 24db lr. low pass 908hz 24db lr peq1 -7.1db at 1.92k with Q of 6. peq2 +7.1db at 154hz low shelf compression driver has high pass 1.36k 24db butterworth and polarity inverted. peq1 -6.5db at 3k q of 2 peq2 -2.6db at 1.5k q of 1 peq3 -2.6db at 6.47k q of 5 peq4 -7.1db at 3.17k q of 30 (is q of 30 a misprint or meaning something else?) compression driver has passive crossover at 6.3k Although these settings sound ok, i still think there is something missing from the sound wether that be a phasing issue or eq. But without smaarting the system i dont know. So can anyone tell me the reasoning behind what i think are strange eqs and crossover points.
	07756215776.

Conanski Members Profile Send Private Message Find Members Posts Add to Buddy List Old Croc Joined: 26 January 2006 Location: Ottawa, Canada Status: Offline Points: 2537	Post Options Post Reply Quote Conanski Report Post Thanks(0) Quote Reply Posted: 08 September 2018 at 12:09am
	Dual 12s have high pass 71.5hz 24db lr. low pass 908hz 24db lr peq1 -7.1db at 1.92k with Q of 6. - Out of band correction of driver breakup, not uncommon. peq2 +7.1db at 154hz low shelf compression driver has high pass 1.36k 24db butterworth and polarity inverted. - That appears to leave a gap but if the acoustic response sums flat that is all that matters. peq1 -6.5db at 3k q of 2 peq2 -2.6db at 1.5k q of 1 peq3 -2.6db at 6.47k q of 5 peq4 -7.1db at 3.17k q of 30 (is q of 30 a misprint or meaning something else?) - that is a narrow cut, not a misprint I suspect. compression driver has passive crossover at 6.3k - scratch that.. this is a coax compression driver with a smaller driver handling the upper frequencies, nothing to see here. Edited by Conanski - 08 September 2018 at 12:15am

snowflake Members Profile Send Private Message Find Members Posts Add to Buddy List Old Croc Joined: 29 December 2004 Location: Bristol Status: Offline Points: 3122	Post Options Post Reply Quote snowflake Report Post Thanks(0) Quote Reply Posted: 08 September 2018 at 12:14am
	do you have any sort of measurement mic and RTA? dual 12 peq1 is to get rid of a peak which is above the passband but right in the vocal range. peq2 is your baffle step correction. the crossover points have a gap between them because a dual 12 will start to beam quite a lot and they are trying to correct the on axis response. the acoustic crossover will be much nearer 1.36k. a better way to deal with beaming is to use a 2.5way crossover but that's another subject. thread about compression driver here: https://forum.speakerplans.com/eqing-bms-4590-on-2236-horn_topic101004.html

snowflake Members Profile Send Private Message Find Members Posts Add to Buddy List Old Croc Joined: 29 December 2004 Location: Bristol Status: Offline Points: 3122	Post Options Post Reply Quote snowflake Report Post Thanks(0) Quote Reply Posted: 08 September 2018 at 12:16am
	the 6.3k crossover is because it's a dual diaphragm compression driver I think

jamie-ashton-solo Members Profile Send Private Message Find Members Posts Add to Buddy List Young Croc Joined: 26 January 2009 Location: staffordshire Status: Offline Points: 728	Post Options Post Reply Quote jamie-ashton-solo Report Post Thanks(0) Quote Reply Posted: 08 September 2018 at 9:58am
	Yes it is the bms 4590 coaxial compression driver. 2" + 1" dual diaphragm. Thank you for responses so far. I do have an rta mic and smaart. But my knowledge is limited and struggle to interprate the results I see. If anyone could help with this is be very grateful as if love to get this system right. Edited by jamie-ashton-solo - 10 September 2018 at 2:48pm
	07756215776.

Pasi Members Profile Send Private Message Find Members Posts Add to Buddy List Old Croc Joined: 25 April 2010 Location: Knutsford Status: Offline Points: 2732	Post Options Post Reply Quote Pasi Report Post Thanks(0) Quote Reply Posted: 10 September 2018 at 8:55am
	That sounds almost like an Ohm box when looking at those numbers. Anyway, out of band EQ is not unhead of anyway and that EQ with Q of 30 is very very narrow so it indicates that it's taking some resonance peak of the response. Not sure without seeing and measuring the cabinet. But typically that is not used with BMS coaxial, especially that 4590 ferrite version.