[this_is_vv]

this is a graph from scanspeak 18W/4531G and raal 140-15d.....it is connected to active XO and they are getting from 70-1800hz to Scanspeak and 1800 hz -20Khz raal....


V

[FullRangeMan]

Nice graphic, with this 2K drop and the 10-20K down it seems sound great.

[this_is_vv]

Nice graphic, with this 2K drop and the 10-20K down it seems sound great.

and i am worried about this drop...and i dont understand the bump around 300....i am reading around 200-300 there is a bump because of floor...

V

[FullRangeMan]

The 2K drop is normal when XO is used, any drop in the treble is good, unless it is huge, but it is not the case.
I was unable to find the 1531G woofer Freq chart in the scan-speak site.
http://www.scan-speak.dk/woofer.htm
Maybe this bump belongs to the woofer himself, just a idea.
Consider this Carver Amazing Freq Chart below, it had huge drops and the sound is the most beautiful treble and 3D image I had listen;

[this_is_vv]

The 2K drop is normal when XO is used, any drop in the treble is good, unless it is huge, but it is not the case.
I was unable to find the 1531G woofer Freq chart in the scan-speak site.
http://www.scan-speak.dk/woofer.htm
Maybe this bump belongs to the woofer himself, just a idea.
Consider this Carver Amazing Freq Chart below, it had huge drops and the sound is the most beautiful treble and 3D image I had listen;

i apologize ...it is the following driver

http://www.madisoundspeakerstore.com/scanspeak-woofers-6-7/scanspeak-revelator-18w/4531g-7-mid-woofer-4-ohm/

V

[FullRangeMan]

OK, it wont had any bump in the factory chart, but the factory chart is made in a boxed enclousure.
So it may be the floor, corner or anything more. If the sound is good in this range you dont had a problem.
Anyway its not bad for a 6 inches mid that is suited for a box, as it had low QTS=0,35 and hi mass cone=17,5g.

[this_is_vv]

OK, it wont had any bump in the factory chart, but the factory chart is made in a boxed enclousure.
So it may be the floor, corner or anything more. If the sound is good in this range you dont had a problem.
Anyway its not bad for a 6 inches mid that is suited for a box, as it had low QTS=0,35 and hi mass cone=17,5g.

the voice is really good...i am powering the tweeter with Ncore and i got another pair of Ncrore to build this weekend which will power the scanspeak and the AE will be powered by 200 W B&K amp


V

[studiotech]

I would first get the woofer hooked up.  It is most "natural" sounding to have the slope from the bass all the way into the highs. The 300Hz is most likely room related.  Most homes with an 8-9ft ceiling experience 200-300Hz weirdness.  Plus right now, your getting the floor bounces effects of the 18W about 2ft above the ground. 

For the dip around 2000, try flipping the polarity of the Raal to see if the dip gets better or worse.  You can do this at the amp terminals or in the DSP.  Also, what slopes are you using?  Steeper will have less overlap, so possibly less interaction to cause cancellations.  Also, the Raal's response by 2KHz is already dropping off, so IF you cross that low, you will need to boost its lower end.  It do not recommend crossing this low AND needing to boost.  Try 2.5-3KHz on the Raal.  This is where you will be more naturally working with the rolloff of the driver.

I'd also do some sweeps closer to the speakers to see less room effects in the midrange.  try them at 1ft centered on the Raal.

Greg

[jimdgoulding]

I'm wondering that if you could tame the bump at 2500 you might accomplish the same thing?   It doesn't appear until north of the crossover point.  Could diffraction be contributing? 

[AJinFLA]

and i am worried about this drop...and i dont understand the bump around 300....i am reading around 200-300 there is a bump because of floor...

V

The >2k dip is poor integration between the drive units, at the mic position. Your crossover needs work, as does your vertical spacing between the drivers. The bump is the dipole peak from the driver/baffle configuration you've chosen.
To be quite frank (even though I'm AJ), your XO points and general configuration might need some reconsideration. A single 6.5" ("Scanspeak" or not) is woefully inadequate for dipole operation to 70hz except for very low volume listening, since they will require significant eq/boost to get good integration with sub at 70hz. You may want to consider doubling to around 120-140hz (which is probably the absolute highest you would want o run that big H baffle sub). Ditto for raising XO on RAAL nearer 2-2.5k or so. Or not.
It's all a learning process and you only have one pair of ears to please.

cheers,

AJ

[jimdgoulding]

I'm wondering that if you could tame the bump at 2500 you might accomplish the same thing?   It doesn't appear until north of the crossover point.  Could diffraction be contributing?

Whoops, I meant 200Hz plus in which case diffraction wouldn't be an issue.

[a.wayne]

this is a graph from scanspeak 18W/4531G and raal 140-15d.....it is connected to active XO and they are getting from 70-1800hz to Scanspeak and 1800 hz -20Khz raal....


V

Based on microphone distance and proximity in the photo posted , cant see how you are getting any accuracy below 1.5K, 2k seems reasonably for accuracy ...

[this_is_vv]

I would first get the woofer hooked up.  It is most "natural" sounding to have the slope from the bass all the way into the highs. The 300Hz is most likely room related.  Most homes with an 8-9ft ceiling experience 200-300Hz weirdness.  Plus right now, your getting the floor bounces effects of the 18W about 2ft above the ground. 

For the dip around 2000, try flipping the polarity of the Raal to see if the dip gets better or worse.  You can do this at the amp terminals or in the DSP.  Also, what slopes are you using?  Steeper will have less overlap, so possibly less interaction to cause cancellations.  Also, the Raal's response by 2KHz is already dropping off, so IF you cross that low, you will need to boost its lower end.  It do not recommend crossing this low AND needing to boost.  Try 2.5-3KHz on the Raal.  This is where you will be more naturally working with the rolloff of the driver.

I'd also do some sweeps closer to the speakers to see less room effects in the midrange.  try them at 1ft centered on the Raal.

Greg

yes i changed the XO to 2500 and will measure it in week...out right now...i will also do measurement with close to RAAL and scanspeak ....this was a very rough test i did....

V

[this_is_vv]

The >2k dip is poor integration between the drive units, at the mic position. Your crossover needs work, as does your vertical spacing between the drivers. The bump is the dipole peak from the driver/baffle configuration you've chosen.
To be quite frank (even though I'm AJ), your XO points and general configuration might need some reconsideration. A single 6.5" ("Scanspeak" or not) is woefully inadequate for dipole operation to 70hz except for very low volume listening, since they will require significant eq/boost to get good integration with sub at 70hz. You may want to consider doubling to around 120-140hz (which is probably the absolute highest you would want o run that big H baffle sub). Ditto for raising XO on RAAL nearer 2-2.5k or so. Or not.
It's all a learning process and you only have one pair of ears to please.

cheers,

AJ

You are AJ, whose speaker i appreciated most at Washington DC...i was the guy with DALI CD stimela .....

Well i will be doing as you said for AE woofer from Hframe to 150 once i have another amp i need...next phase i will plan better...wil do some more measurement in a week time...will see how much difference it can make...

though i am really liking the sound...

V

[6thplanet]

I'd also guess the bump around 300Hz is prolly the dipole peak from the baffle. The squiggly lines don't always determine if a speaker is going to sound good or not, let your ears make the final decision... Must be nice to have a set of Raals/Scans to play with!!