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New amp for Kef THX 45b subwoofer ? M & K

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Old 12-11-2009, 7:46 PM   #1
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New amp for Kef THX 45b subwoofer ? M & K

My Kef died a while ago and I have decided to get it up and running again, looked at the BK modules and also found these on eBay M & K VX-1250 SubWoofer Amplifier 272W Sub Woofer Amp on eBay (end time 09-Dec-09 13:24:42 GMT) also the bigger one

Megabassll Subwoofer Amplifier Plate w/Crossover 420W on eBay (end time 24-Nov-09 13:36:46 GMT)
What woulkd they be like compared to the old KEf amp it was THX and i suppose these have no THX switch thanks
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Old 12-11-2009, 7:59 PM   #2
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Re: New amp for Kef THX 45b subwoofer ? M & K

If you looking for a new subwoofer amp then try these

Rythmik Audio • Subwoofer plate amplifiers

not sure about M&k subwoofer amp as its only 272w
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Old 12-11-2009, 8:21 PM   #3
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Re: New amp for Kef THX 45b subwoofer ? M & K

The megabass II is more like 250-300 WRMS. It is a common design.

I have one for my PC setup.
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Old 12-11-2009, 11:58 PM   #4
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Re: New amp for Kef THX 45b subwoofer ? M & K

Kef subs don't break, it's a figment of your imagination. Go and buy a new KEF.



This is getting annoying, we have hundreds of posts of KEF subs breaking and KEF stick their heads in the sand and say we are biased...

Take a deep breathe Dave and try and help the OP...


What was the Wattage of the old Amp plate?

Dave
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Old 16-11-2009, 11:01 PM   #5
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Re: New amp for Kef THX 45b subwoofer ? M & K

Hi its a 15 inch driver and a 300 watt amp, the RRP price was £800 a few years ago this is the link to them KEF Audio - 21st Century - TDM45B
It all worked fine untill the amp went bang and KEf could not repair the amp, and they did not have any spare amps and then it became discontinued ! So I have a big black box with a 15 inch driver but no amp.
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Old 17-11-2009, 1:58 AM   #6
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Re: New amp for Kef THX 45b subwoofer ? M & K

I reckon you would get a good sub by buying a new amp panel and rebuilding what you have. I would recommend a BK one, but I only recommend them because I bought a 100W one 6 years ago and it still works. I feel guilty every time I recommend them

Dave
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Old 10-12-2009, 6:41 PM   #7
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To get the equivalent of the THX setting then you just need an amp capable of an unprocessed feed to the drive unit.
It relies on the Pre-amp for the low pass crossover and the natural rolloff of the drive unit to comply with the THX specs.

If you want the equivalent of the stereo/music/standard/deep (or whatever they call it on your sub) setting then you'll want one that has switchable EQ to boost the low end.
I hope this helps,

Paul.
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Old 10-12-2009, 7:38 PM   #8
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Something just dawned on me. Ive had my duff PSW2010 lying round for an age now. Ive also had my Behrringer amp lying around waiting for my DIY build. So I whipped out the Kef amp, plugged in the Behrringer and hey presto, a fully working sub again.

Perhaps there is a simple solution akin to that one for yourself too.
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Old 29-12-2009, 11:34 AM   #9
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Quote:
Originally Posted by grahamricho View Post
My Kef died a while ago and I have decided to get it up and running again, looked at the BK modules and also found these on eBay M & K VX-1250 SubWoofer Amplifier 272W Sub Woofer Amp on eBay (end time 09-Dec-09 13:24:42 GMT) also the bigger one

Megabassll Subwoofer Amplifier Plate w/Crossover 420W on eBay (end time 24-Nov-09 13:36:46 GMT)
What woulkd they be like compared to the old KEf amp it was THX and i suppose these have no THX switch thanks
Have you asked KEF for a quote on a new amp, I know this may seem like jumping back into the fire a bit but I have enquired in the past about new amps for my 45b and my PSW3000 and they were only about £150 or so, only sold the 45b for something smaller mind you, got the 3000 instead and that died after 5 years so gave it away!!!

Now looking to either make my own or buy a BK

Last edited by scoobysmiff; 29-12-2009 at 11:39 AM.
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