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Ideal box for B139 ?

 
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Motorcycle Boy
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Joined: 13 Dec 2005
Posts: 13
PostPosted: Thu Dec 15, 2005 9:57 am    Post subject: Ideal box for B139 ? Reply with quote
Hi

reading and surfing about the B139 I learned that the Concerto's box seems to be "too small" for it to deliver the best it can. In stead of 62 L it should have something around 150 L Shocked

Did anybody ever try to develop the ideally constructed and sized loudspeakerbox around this B139 Question
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ColinR
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Joined: 31 Jul 2004
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PostPosted: Thu Dec 15, 2005 11:53 am    Post subject: Reply with quote
Around 100 litres, peoples' minds tend to gravitate towards transmission lines like Bailey, Webb, Atkinson, etc, where you get more bang (fast bass) for a smilarly sixed box.

The infinite baffle/reflex designs I know about that are in the ~100 litre class include.

A Heathkit design from the early 70's, which had a 2'*4" port at it's base filled with a foam wedge.

A Dutch pentagonal (with two short sides) CS7, the kits were made in Friesland. Occasionally seen on German ePay.

The Schlank und rank isn't a pigmy either.
http://www.hifiloudspeakers.info/Anatomy/KEFDocuments/KEFGermanGallery/pages/p24.htm
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boyzo
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PostPosted: Sat Jan 07, 2006 10:20 pm    Post subject: Re: Ideal box for B139 ? Reply with quote
160 liters vent tuned to 23Hz = room shaking bass


Motorcycle Boy wrote:
Hi

reading and surfing about the B139 I learned that the Concerto's box seems to be "too small" for it to deliver the best it can. In stead of 62 L it should have something around 150 L Shocked

Did anybody ever try to develop the ideally constructed and sized loudspeakerbox around this B139 Question
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adam2a3
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Joined: 04 Nov 2011
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PostPosted: Sun Nov 06, 2011 9:44 am    Post subject: Re: Ideal box for B139 ? Reply with quote
Hi boyzo, any dimensions for the 160 lt boxe's port available? I am currently using the CS7 box as a sub cabinet. Regards,adam2a3

boyzo wrote:
160 liters vent tuned to 23Hz = room shaking bass


Motorcycle Boy wrote:
Hi

reading and surfing about the B139 I learned that the Concerto's box seems to be "too small" for it to deliver the best it can. In stead of 62 L it should have something around 150 L :shock:

Did anybody ever try to develop the ideally constructed and sized loudspeakerbox around this B139 :?:
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ColinR
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PostPosted: Mon Nov 07, 2011 1:06 pm    Post subject: Reply with quote
160l box ~100cm*34cm*47cm, port 10cm dia * 8cm long.
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adam2a3
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PostPosted: Mon Nov 07, 2011 4:46 pm    Post subject: Reply with quote
ColinR wrote:
160l box ~100cm*34cm*47cm, port 10cm dia * 8cm long.


Thanks CollinR, I will give it a try keeping the CS7 crossover (low pass section). Regards, adam2a3
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speakerguru
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Joined: 18 Nov 2005
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Location: Green Hut, Tovil
PostPosted: Tue Nov 08, 2011 10:21 am    Post subject: Re: Ideal box for B139 ? Reply with quote
Motorcycle Boy wrote:
..... I learned that the Concerto's box seems to be "too small" for it to deliver the best it can. In stead of 62 L it should have something around 150 L Shocked


That is just the small signal frequency response. Don't forget to consider the large signal requirements. If you want X dB spl at 20Hz then you have to be able to shift Y cc of air, otherwise the B139 will just be hitting the end stops when you drive it with a big amplifier in a big box.
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proffski
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Joined: 22 Aug 2003
Posts: 1297
Location: Tewkesbury UK
PostPosted: Fri Nov 11, 2011 2:34 pm    Post subject: Reply with quote
Subtly and elegantly put, some other aspects to consider to be found here:

http://www.klippel.de/uploads/media/Assessing_the_large_Signal_performance_of_Loudspeakers_03.pdf
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