15" two way with natural roll off?

[darkmatter]

Hello, was thinking of making a 15" two way speaker, but wanted to take a minimalist approach to the crossover.
Does anyone know a good 15 incher that rolls off naturally so I can just use a high pass on the tweeter?
Was looking at this speaker - any advise is appreciated
Thanks
Mike
Beyma SM Series Speakers - Beyma SM Series SM-115K speaker - Beyma SM-115K 1,000 watt 15" woofer for all bass applications. Beyma SM-115K and other Beyma 15" speakers here.

COPY the best reviewed complete design you can afford. Do not get locked into minmal Xover parts count.

Midbass -to- Horn_Tweeter time alignment is very important, and it is worth some research to study "quasi-optimal" crossovers, like the LeCleach work, which use 2-different slopes to improve phase and time alignment with long horns.

http://www.diyaudio.com/forums/mult...sover-high-efficiency-loudspeaker-system.html


Your best option is probably to KEEP READING until you find a well reviewed 2-way design which meets your cost, complexity, sound quality, and physical size requirements to copy.


The best 15" MIDBASS speakers have:
Mms ~70-90 grams
Le < 0.8mH
Qtc around 0.25-0.35
Bl around 15-20
well controlled cone break-up

Researching this carefully this woofer meets many of the criteria above

Beyma SM-115/N

Quite smooth and high performance and models well in enclosures around 150 litres and a bit above.

I think though a minimum of a second order filter will still be needed if any prospect of hifi level of performance is required.

I do like this unit as well which claims hifi like performance but not sure if this would be suitable for your project

Precision Devices PD.153C01

https://youtu.be/dMJDeCvfvBI

 

[darkmatter]

Hi Derek,

Thanks for the response

Any thoughts on the Precision Devices PD.153C01 which looks a bit smoother that the 158?

Thanks

Simon

 

[Overkill Audio]

PD 158

Hiya,

I have used a few different Beyma, Volt, Precision Devices, 18 Sound and RCF 15 inch drivers over the last 10 years or so.

Personally I think a even good 15 inch low Mms / high Bl / low Q driver is best crossed over below 800 Hz and an 18 inch below 300 Hz.
But if you do want to push an octave or two higher and cant use a 12 inch my recommendation would be for the Precision Devices PD158.

The Beyma SM115K (not N) is a great driver with better bass than the PD 158, but above 500Hz the PD is vastly superior.


Attached are a few pics.
Hope this helps and all the best
Derek.

 

[Mike in NJ]

I have been looking a bit deeper also, and have spoken with someone who has used this driver with very good results.
http://www.paudiothailand.com/pdf/products/E15-350N1.pdf

 

[POOH]

If you don't mind taking a chance on a vintage driver the Altec Bi-Flex is specifically designed for what you seek. The 415-C can sound quite good with a high sensitivity ribbon to supplement the top octave

http://www.voiceofthetheatre.com/images/412C.415C.1.jpg

 

[darkmatter]

Hiya,

I have used a few different Beyma, Volt, Precision Devices, 18 Sound and RCF 15 inch drivers over the last 10 years or so.

Personally I think a even good 15 inch low Mms / high Bl / low Q driver is best crossed over below 800 Hz and an 18 inch below 300 Hz.
But if you do want to push an octave or two higher and cant use a 12 inch my recommendation would be for the Precision Devices PD158.

The Beyma SM115K (not N) is a great driver with better bass than the PD 158, but above 500Hz the PD is vastly superior.


Attached are a few pics.
Hope this helps and all the best
Derek.

When you made these comparisons how high did the 158 go?

My loading will be in a 170 litre vented enclosure

 

[RDLewis]

Robert Bastanis seems to do remarkable things with his 15 inch drivers, running them minus crossovers, Check out his Matterhorn's. But the Specs for Faital 15PR400. if accurate ( ? ), look very impressive, partially at the top end, As good as many 8 inch drivers !

http://www.faitalpro.com/products/files/15PR400/8/15PR400_datasheet_8.pdf

 

[Overkill Audio]

When you made these comparisons how high did the 158 go?

My loading will be in a 170 litre vented enclosure

Hi Dark Matter,

I always use small sealed box loading and the use DSP and Eq to fine tune the curve to my needs.
In my experience the PD 158 is a superior in the low midrange and midrange to any other driver I have used. Its a stunning piece of kit!

The drivers spec is a perfect storm for a 15 inch low midrange driver....
The Mms to Bl is key, also the Qts and Qms are perfect for a big driver, also the 4 inch single layer voice coil....its all ideal.
I havn't used the 153 CO1, it looks more of a bass driver, esp its higher Mms / lower Bl....

Hope this helps and all the best
Derek.

 

[WinnieNL]

Hi Mike,

I'm wanted to share a link to my one thread in which i'm busy making plans for a 12" + horn + 12"/ 15" subs.

There are some links in the first post where you can find some 15" suggestions. Also the Maximus-12 link leads you to the diysoundgroup. They also have a 15" diy speaker.
The link to 6moons is a review of a minimalist 2-way speaker.

Good luck!

http://www.diyaudio.com/forums/multi-way/285652-2-way-diy-hifi-speakers-eighteensound.html

 

[Overkill Audio]

Pd 158 crossover

When you made these comparisons how high did the 158 go?

My loading will be in a 170 litre vented enclosure

I used the PD 158 with the Manger driver and the PD158 covered 80Hz to 1,000Hz beautifully. The fact that it can blend with the Manger at 1,oooHz speaks volumes about the PD 158.

Like any 15 inch driver its off axis performance will start to drop off around 500Hz so best to cross it over around 400Hz if you want to maintain a flat power bandwidth.
This actually complements the Manger very well as its a "beamy" driver.
Using the DEQX I could swap crossover frequencies on the fly and its interesting to hear the different effects, with the Manger 800Hz was the sweet spot.

With smaller drivers with better off axis performance I suggest 4ooHz to 500Hz crossover.

Hope this helps and all the best
D.

 

[darkmatter]

I have been looking a bit deeper also, and have spoken with someone who has used this driver with very good results.
http://www.paudiothailand.com/pdf/products/E15-350N1.pdf

This driver looks good with some EQ by using a series inductor with parallel resistance this can be tuned to flatten the response

http://www.eighteensound.it/Portals/0/PDFs/15MB650.PDF

Another two

http://www.eighteensound.com/Portals/0/PDFs/15ND930.PDF

http://www.eighteensound.it/Portals/0/PDFs/15W930.PDF

 

[darkmatter]

I used the PD 158 with the Manger driver and the PD158 covered 80Hz to 1,000Hz beautifully. The fact that it can blend with the Manger at 1,oooHz speaks volumes about the PD 158.

Like any 15 inch driver its off axis performance will start to drop off around 500Hz so best to cross it over around 400Hz if you want to maintain a flat power bandwidth.
This actually complements the Manger very well as its a "beamy" driver.
Using the DEQX I could swap crossover frequencies on the fly and its interesting to hear the different effects, with the Manger 800Hz was the sweet spot.

With smaller drivers with better off axis performance I suggest 4ooHz to 500Hz crossover.

Hope this helps and all the best
D.

Hi Derek,

I have an additional project which requires a 15" Bass driver to be used in a small enclosure of 80 litres (Sealed)

Presumably the same comments still apply for the PD 158, as the crossover will be around 500-600 Hz then the Beyma SM115K could come into the reckoning.

Regards,

Simon