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A mix of cs-9 and pl301
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gforse
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PostPosted: Mon Jan 25, 2010 6:19 pm    Post subject: A mix of cs-9 and pl301 Reply with quote

Hello! i am new here! i'm from the dutch and i'm just 19 years old! and my english is not that good! Laughing and i'm working on a project. but i'm stuk at some points. let me explain.

i purchased some b300's in top condition! with a filter! bud is stil mis the heads! ( b110B and T52B)

now i want te build a mix of cs-9 and the pl301 of the elektor.

i have made some drawings:

this is a ruff over view.


and this are the building drawings
The measements are in centimeters




and this is are the b300 and filter.




filter type : SP1059

Mid/hi : SP1100 Ser. Nr. 4953
Low : SP1101 Ser. Nr. 4468

Sorry that they are so big, i don't know how to make them small.

But i'm now stuk at the filter section. wat kind of filter sould i buy?

i'm also stuk at the construction of buidling i't of sand.

i want to know is this smart to do? or what changes must i make? or sould i build something different? the topic of Lee and his 105/2 are very nice!! but i thinks its to diffecult for me to maken.

al little adviese please!!

Laughing Very Happy Very Happy Very Happy
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ColinR
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Location: Staffordshire

PostPosted: Mon Jan 25, 2010 7:45 pm    Post subject: Reply with quote

The KEF PL301 was a no-compromise frequency domain design with a trapezoidal mid-treble "box" a'la 104-2, as the trapezoid gives the nearest Pi space dispersion pattern to a sphere.

You're trying to build a box on wheels, a CS9 with a B330B, so use the Ref. 105 bass section and modify the mid-treble to either that of the CS9 or Cantata.

Or use the filter design lurking here and go active Cool .
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gforse
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PostPosted: Mon Jan 25, 2010 7:58 pm    Post subject: Reply with quote

what i found strange is that i found a different schematic of de 105 mk1


and the pl301.


the pl301 uses dn27 and cs-9.

but what effect does is have that all 3 units are mounten straight in de baffle?

is this worth al the building? i'm a lover of much base but also very warm hi!
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Lee in Montreal
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PostPosted: Mon Jan 25, 2010 9:08 pm    Post subject: Reply with quote

The B300 seems to have an enclosure with around 120L volume in that drawing, which would most likely be fine for a vented enclosure. But perhaps a bit too big for a sealed one, where 70 to 90 litres would be recommended for best efficiency. Unless I am fooled by the double-walling. Will the cavities be filled with sand or something similar?
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gforse
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PostPosted: Mon Jan 25, 2010 9:21 pm    Post subject: Reply with quote

Lee in Montreal wrote:
The B300 seems to have an enclosure with around 120L volume in that drawing, which would most likely be fine for a vented enclosure. But perhaps a bit too big for a sealed one, where 70 to 90 litres would be recommended for best efficiency. Unless I am fooled by the double-walling. Will the cavities be filled with sand or something similar?


de double-walling wil be filled with sand. as the idee of the pl301. also is the volume for the bass of the pl301 80L

so will this constuction work? or does it mess things up?
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ColinR
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PostPosted: Mon Jan 25, 2010 10:27 pm    Post subject: Reply with quote

Quote:
but what effect does is have that all 3 units are mounten straight in de baffle


Using a time or frequency domain aligned crossover in a "box" would lead to an odd polar reponse.

So you might have a "sweet spot" but off axis the presentation might be strange.

Remember you're using the wrong bass unit a B330 SP1060 not a B300 SP1071 so things may sound even stranger.
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Lee in Montreal
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PostPosted: Tue Jan 26, 2010 12:17 am    Post subject: Reply with quote

gforse wrote:
so will this constuction work? or does it mess things up?


My thinking is that you are not being efficient with volumes. Double walling + sands is a great idea and should be restritecd to the bass unit. The mid and tweeter don't need such hardcore double-walling. So you are wasting a lot of space in your living room. Which was actually the magic with the 105 and 107. The heads were much smaller and all that was needed. A 105/2 has 70 litre volume and looks small. My own Evo 105 project also looks small despite 90 Litre volume, and it also has separate mid-highs enclosure. I made the enclosure low but deep so that visually it doesn't take up that much space. At least to the eye.

Lee
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gforse
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PostPosted: Tue Jan 26, 2010 8:22 am    Post subject: Reply with quote

So what is wise to do? buy a compleet matched 105/2 ? an then make a new box arround it?

later during the project i began searching more and found the project of lee. i think those are asome! and i like the idee but then higer and les deep. but that would be almost making a copy of it.

also guys from my dutch forum thinks its a waste of time working wild old units. but i think is worth it or not? there are some guys who thinks its asome!

What is wise to do? and what would you guys do?

Thanks so far Very Happy Very Happy
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ColinR
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PostPosted: Tue Jan 26, 2010 1:16 pm    Post subject: Reply with quote

Quote:
What is wise to do? and what would you guys do?


As wood is allergic to me Crying or Very sad i.e. if given a £2000+ saw table with a piece of wood fully clamped in it, I'll manage to cut a wavy line!


So as a non-woodworker (metal lathe or milling machine - no problem) I'd adopt a K.I.S.S. approach.

Get some cheap, old blown up speaker boxes and mount the B330, get a plank and mount the B110B and T52, use your existing crossovers and put wool jumpers behind the B110Bs OR make one 60 litre B330 box and plank for a mono setup.

If you like the sound carry on with your design, if not, flog the bits.

Make sure that the mono box panels can be used for something else.
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gforse
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PostPosted: Tue Jan 26, 2010 1:44 pm    Post subject: Reply with quote

so ure saying make a demo model en play arround with it? i'm stil missing the b100b and the t52B i'm searching for them.

i have a big subwoofer that i build many years before fore a drive in show. a kappa 15 from eminence it's 185L Shocked its a square box of 57cmx57cmx57cm

i'm putting the b300 in it! but first i have to make a new front panel and i have to maken the bas pipe's closed!


to morrow i will finis it. but i listend now and it sound very nice bud at a few meters the bass was gone. i geus that when i close the pipe's it sound a lot beter! Very Happy
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gforse
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PostPosted: Wed Jan 27, 2010 12:41 pm    Post subject: Reply with quote

well i dit some worke in winISD and i had extent the bass ports to 50cm. and i make some adjustments



it was very impressif because it whent very low! up to 25hz. according winISD it can go to 20,11hz. but i found it not so power full. the bass is there but is seem like it can not build up any power. at 1,5 Meters is sounds great! nice deep bas but very thight! and nothing distorted. i think its because its in a bassreflax box.

i'd never heard the b300 in the orginal 105 but i did heard the heads of the 105 and that sounds great!



how sounds a b300 in a closed box? i think much beter than now or not?

also i have a active adjustable 3way crossover and i turn it a lot and the cross over at 400hz. and is sounds fine to me!

what is wise to do ? buy an 105/2 and make a new box?

and what sould i do go for sand? or good bracing an think walls?

I'm doubt about what design i sould thouse. the one is post above or a simular idee of the one lee's making!?
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Lee in Montreal
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PostPosted: Wed Jan 27, 2010 9:24 pm    Post subject: Reply with quote

Your idea of using a hollow cavity and fill it with sand is very interesting. If I were you, I would make a design around that principle. But not using thick wood as walls, but perhaps thin 3mm Massonite or fiber particle. Most likely, tops, bottoms and front will be thick wood, and everything else will be sand. And as you use very thin walls to contain the sand, why don't you experiment with shapes that best suit soundwaves? Perhaps a round back, or curved sides. That will make the project stand out, and the results even more interesting. Be creative, make it funky.

BTW The B330 and 300 have very compliant surrounds with very limited excursion. I do not think it will work great in a too big enclosure, or with bass reflex. Maybe I am wrong...

http://www.bonavolta.ch/hobby/en/audio/lo_damp.htm
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gforse
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PostPosted: Wed Jan 27, 2010 9:41 pm    Post subject: Reply with quote

that is also an idea! make the top, bottom baffle and end from thick wood. and some bracing in the middel and then thin walls fil them up with sand and its one thick wall!? but what kind of sound produce the b300? it the bix box above it gows very low but it mis the power! at 1 meter its nice but at 3-4 m its almoste gone!

but how to calculate bracing and roundings? i want to make 90L and if i will it up with pritex and dr bailays long hair is x1,25 so its then 112.5 L and then calculate the bracin in it.

can some one help me with it?
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Lee in Montreal
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PostPosted: Wed Jan 27, 2010 9:58 pm    Post subject: Reply with quote

The B300 is designed to fit a 70-90 litre enclosure in sealed form. If you increase the size, you are loosing in output.

As for designing the bracing, invent your own process.

Here's what B&W did with the Matrix serie


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gforse
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PostPosted: Wed Jan 27, 2010 11:02 pm    Post subject: Reply with quote

that looks cool but it isn't easy to make i think. what do i must know by design the bracing?
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