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Old 7th May 2007, 09:05 AM   #1
Thomo is offline Thomo  United Kingdom
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Default New Cabinet Opinions & Advice Sought

Hi everyone.

I have A pair of Tannoy Little Golds and need some new cabs to give a better bass performance. Using a Standing Wave Calculator on Vikash's Website (with thanks), I have come up with internal dimensions of:

HEIGHT - 1000mm
WIDTH - 450mm
DEPTH - 400mm

I think this should give a response down to around 35Hz

spec sheet posted below, driver is K3148.

Any advice or opinions will be greatly appreciated.
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Old 8th May 2007, 12:14 AM   #2
GM is offline GM  United States
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Default Re: New Cabinet Opinions & Advice Sought

Greets!

FYI: Tannoy floorstander progress

Anyway, your 180L = ~6.35664 ft^3, so for ~35 Hz I recommend at least a 19.635"^2 area vent (5" dia.) x 2" long, which yields a ~T/S max flat alignment based on my specs from the previous thread.

That said, a Vb = Vas, Fb = Fs MLTL goes down to a ~30 Hz/F3, raises the driver up around ear height, and has enough Vb for a bit more tuning flexibility:

L = 61.663"
W = 20.7788"
D = 12.847"
zdriver = 24.5" (37.912" from floor assuming 19 mm material thickness)
zport = 58" (50" for a ~31 Hz T/S max flat)
rport = 2.5"
lport = 0.75"

With either, stuff to 'taste' and if 'boomy' in-room, then lower Fb either with a longer vent or damping the vent to make it ~aperiodic.

GM
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Old 8th May 2007, 01:25 PM   #3
Thomo is offline Thomo  United Kingdom
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Great! Thanks for your help. The thread you linked to is very informative.

Looking at your reply, I am considering building these instead as they're narrower than my proposed design. Are these the same as your build?

Also, just for info, this same driver was used in the Tannoy Edinburgh:

http://www.tannoy.com/Edinburgh

Would I like to build a pair of those!

Regards, Lee.
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Old 8th May 2007, 02:12 PM   #4
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GMs cabinet will be a good 'un. Believe me, Greg knows what he's doing.

Now I've said that...

> http://www.tannoy.com/Edinburgh Would I like to build a pair of those!

Well, if you like them, why don't you? There's nothing about Edinburgh that couldn't be easily DIYed. Looking at the details on Tannoy's site it's a simple enough cabinet (they even give the dimensions) with distributed (nee Onken) vents. All we'd need to do is calculate the size of the slots which form the vents and that's easy enough.
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Old 28th December 2007, 08:38 PM   #5
Thomo is offline Thomo  United Kingdom
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I know this is an old thread, but I am finally in a position (both financially and WAF) to build some new cabs. And if you chaps don't mind I need some help and advice please.

I am now thinking along the lines of: (internal dimensions)
H=1070mm
W=300mm
D=400mm

I am having to make them as narrow as possible due to a lack of space.

As suggested by Scottmoose, I would like to make them with a slotted port construction, like the Tannoy Edinburghs, onken's etc. I have no idea how to calculate the port length etc though as I am a bit of a noob to building speakers.

Any help will be greatly appreciated.

Regards, Lee.
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Old 30th December 2008, 04:06 PM   #6
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I`m a new member to the site and cannot email to members yet so have had to resurrect this thread. I too am a LGM owner wanting a little more bass but with a small living room and wife to consider so my dream of building Edinburgh clones is out. I too am planning boxes in 18mm mdf roughly 100cm H 39cmW 34cmD giving around 100 L internal volume with simple bracing. I`m getting very confused trying to use cabinet calculators to work out where the bass will go down so could someone tell me if this is worth building and how much lower the bass will go compared to my LGM cabs? Some of the technical terms go over my head but I`d appreciate any advice any of you could give me.
Also - Thomo did you build yours and how do they sound ?
Many many thanks in advance.
Regards
Fraser
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Old 30th December 2008, 04:33 PM   #7
Thomo is offline Thomo  United Kingdom
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Hi Fraser, welcome to the forum.

To be honest, due to a lack of funds and my wife doing a total "U-Turn" when she saw the size of the proposed cabs, I sold my LGM's. I'm now using a little pair of Jamo Concert 8's.

One really good tweak, is to replace the rather poor quality electrolytic capacitor on the bass/mid with something of better quality. I think it's around 15uF, maybe more. A good quality film cap, or even Black Gate AC's will work really well, and give better mid/bass detail.

I also removed the time delay circuit from the tweeters, which made them far more detailed in the treble region, but more"enthusiastic".

Have you tried WinISD? It's a really simple program to use, and seems to give good results.

Cheers, Lee.
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Old 30th December 2008, 10:17 PM   #8
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Cheers for the reply. How sad that you sold them - I`ve had mine nearly 20 yrs - started with little reds - moved up to LGMs about 1999 and will never part with em unless space allowed me to get some 15" jobs.
When you say enthusiastic do you mean fierce?? I do prefer a smooth treble - with this in mind would you recommend the sync removal?
Also how much are the replacement caps you mention?
Cheers
Fraser
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Old 30th December 2008, 11:03 PM   #9
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Hi Fra

been burning the midnight oil I've been thinking about your predicament and was wondering if Scottmoose might see if, something like the half chang could be reworked to accomodate your drivers, I'd certainly like to try in with my 10 inch units.

cheers philip
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