Suggestions for 15" mid bass driver

Kim Anker Hansen

Freshman
May 19, 2017
6
0
1
39
Denmark
Hi
I have a set of older Danish-produced D-pac am2 speakers which contain 1 *15" (18sound 15w1200) and 1 * 2" (Beyma cp850nd) mounted on a large custum built horn, about 500mm deep. They are crosed at about 780hz.
However, the problem is that the 15w1200 is no longer available and have to change a few of them. Had been nice to possibly switch to neo magnet.

Have the following ideas:
18sound:
15mb1000
15ntlw3500
15nw9300
new 15nmb1000?

Beyma:
15p80nd
18p80fe

B & C
15ndl88

Other suggestions? and pluses and minuses on the following units for a 2 way Top, that almost always runs 3 way with sub.

Sincerely
Kim Anker Hansen
 

Antti Laine

New member
Sep 1, 2019
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44
Finland
Hi

By just judging by parameters and somewhat smooth top end response for 2way use, 18sound 15nmb1000 and Beyma 15p80nd would be my go to candidates.

I have no actual experience with these models, but I have replaced many old or outdated oem speakers with Beyma and 18sound products with success.

Despite the lowish xo of 780Hz, its very beneficial to not have any sharp resonances even 2 octaves above the x/o frequency for good "big HiFi" sound quality. In your case the horn would amplify these nasties and probably beam 'em like *ell. I have tried this myself ;)

Additionally there would be possibility of frequency overlapping by high and low shelf filtering near the x/o frequency to aid the polar pattern horizontally, and if the said speaker is coaxial horn, also vertically. This is practically possible only if both drivers have nice response.

Do You have any other physical measurements of the horn in front of 15" driver, mainly throat area and mouth area? 500mm deep horn would aid the low end sensitivity roughly to the 1/4 wave resonance point of 170Hz or higher. Does the speaker use bass reflex ports to aid low end sensitivity? I could not find any datasheet nor measurements for any of the D-PAC products....

Cheers, Antti
 

Kim Anker Hansen

Freshman
May 19, 2017
6
0
1
39
Denmark
Hi Antti
15 "is placed in a Ca 80 liter bass reflex cabinets, tuned to Ca 50hz. It is only the 2" which is horn loaded. I have been in contact with 18sound and got data at 15nmb1000 very early. It works best in a smaller cabinet after simulating on it. But thinking one of the Beyma models maybe is the way for me.
Mvh
Kim
 

Uwe Riemer

Freshman
Mar 3, 2011
117
3
18
Germany
And then again, the 15ntlw3500 looks so tempting
You need to ask yourself a couple more questions:
How much power do you have available?
Where do you want to cross over to sub?
Are the ports large enough to support a high excursion driver?
How will the ports effect midrange?
Can you adjust the length of the ports or in other words: do you own the Fein Multimaster :) ?
 

Kim Anker Hansen

Freshman
May 19, 2017
6
0
1
39
Denmark
Hi Uwe
Currently, the Dpac system is driven by the Lab group fp10000q (hi / mid) and fp14000 on sub, as well as some fp6400. However, bought a powersoft x4 to play a little with fir on them.
I have not rated the 15ntlw3500 xmax at 8.3mm to be the eye-catching problem compared to the original 15w1200 xmax at 6mm.
The cabinet is 80L. And tuned to 50hz which seems in winisd to fit ok to 15ntlw3500. There are 2 reflexes of about 115cm2 each. They are most often crosed at 80-100hz so do not think port noise is a problem.
I am a carpenter so have considered building brand new cabinets. However, it currently seems to fit ok.
Mvh
Kim
 

Uwe Riemer

Freshman
Mar 3, 2011
117
3
18
Germany
Hi Uwe
Currently, the Dpac system is driven by the Lab group fp10000q (hi / mid) and fp14000 on sub, as well as some fp6400. However, bought a powersoft x4 to play a little with fir on them.
I have not rated the 15ntlw3500 xmax at 8.3mm to be the eye-catching problem compared to the original 15w1200 xmax at 6mm.
The cabinet is 80L. And tuned to 50hz which seems in winisd to fit ok to 15ntlw3500. There are 2 reflexes of about 115cm2 each. They are most often crosed at 80-100hz so do not think port noise is a problem.
I am a carpenter so have considered building brand new cabinets. However, it currently seems to fit ok.
Mvh
Kim

Hi Kim,

IMO a good midrange enclosure is small and tuned highish with small and therefore short vents, to keep pipe resonance out of the passband and if you cross over at 80Hz, you`ll want the 15" driver to have high max SPL around 100Hz.
An 80l enclosure tuned to 50Hz with 230 cm2 does nothing of the above.

The best midrange drivers according to my sims are 15NMB1000 and 15P80ND, though Xmax figure of the Beyma is interesting with voice coil overhang of 8mm, but both drivers would need an enclosure and tuning very different from yours.

15NTLW probably needs tons of power, but I heard good things about it ( from my dealer :unsure: )

Sims are not reality, so pick up whatever driver you like best, but be prepared to make sawdust, if it does`nt work out well.

Like Peter Morris once said: I would not buy a low/mid driver without demodulation ring anymore ( exception 15NTLW )

From your list of drivers I want to use 15NDL88 with passband requirements similar to yours, but couldn`t give it a real world ride for obvious reasons.
 

Antti Laine

New member
Sep 1, 2019
2
0
1
44
Finland
though Xmax figure of the Beyma is interesting with voice coil overhang of 8mm,

I'm currently using 12P80Fe in a compact active xo full range/mid high cabinet, and when used as full range (with 25 to 55Hz 24dB hp filter depending needed SPL) distortion products rise very suddenly at edge of Xmax limits. When used with subs and xo around 80....130Hz, this does not happen. Xmech is so much more (50mm p-p) that i have not managed never bottom out these drivers mechanically. Amp power used around 1000Wrms/8ohms (Electro-Voice CP-4000S)

About 15NTLW, this a bass driver to my liking, I think it would be bit wasted doing midrange with "only" 98dB/W sensitivity, power hungry....
On real full range cabinet doing low bass and mid range, a good call....