Dynaudio 24w100 sub doable?

[beamnet]

All the readup i do about subwoofers imply these units are worthless as a sub. What would be a good idea to do with a driver with such a low q?

Just bought a set of Dynaudio Recital speakers, i have two 24w100 units laying around. The Recitals are specced 36Hz-20.000Hz, but have conciderably less bass output than my Philips power monitors (no specs). Could i boost the lows with these drivers? I have a few very respectable toroids and caps to make a suitable subamp.

Really apreciate a pointer here!

 

[beamnet]

datasheet datasheet

 

[beamnet]

Further reading on the driver revealed that Qts values of 0.3 and 0.4 are also stated for these drivers. Maybe these are real measured values.

So ripole and TL could be done with 0.4... not optimal, but could give it a try..

 

[Rademakers]

Q

All the readup i do about subwoofers imply these units are worthless as a sub. What would be a good idea to do with a driver with such a low q?

Wouldn't call it worthless, looks ok to me, as long as your room isn't to big. How low do you want it to go? Any size restrictions?

I did also build two TL's for a speaker with Qts ~0,28, sounds fine.

Wkr Johan

 

[beamnet]

Well, i've been bugging this forum earlier about these drivers. I REALLY like TL's

I also have the idea of making a new bed/sub (student room)

So no real size restrictions here. Just looked at the TL again, maybe i'll go for it

But what to do with the drives? 2 TL-s stereo? 1 TL with two drivers?


Bas

 

[phase_accurate]

I don't know if a Ripole makes much sense with these drivers since they don't have much Vd. TL however (though not for a subwoofer) has already been done with a 24W100:

http://www.pmcloudspeaker.com/ab2s.html

Regards

Charles

 

[beamnet]

Those rock!

Does anyone know anything to say about these configurations i came up with (apart from line tapering)?


First one has a "pressure chambre" like a horn, which would benefit the midrange (?). Third would be most effective in terms of cabinet size. Fourth has no equal length pipes, but more folds.

Only the second two allow for driver offset in the line...

My guess is that these PMC's are made like (3). With the help of that cd and driver size i could faily easily backwards engineer the thing, as line length is specified!

Bas

 

[beamnet]

and the designs...

 

[phase_accurate]

Here is a cutaway of a smaller one:

http://www.pmcloudspeaker.com/transmission.html

I remember seing one of a larger PMC model with an even larger back chamber.

Regards

Charles

 

[beamnet]

Don't misunderstand me, i KNOW what a TL looks like. That one has a backfiring port. I want a frontfiring port at the bottom (as on the pic!)

Bas

 

[beamnet]

To make things a bit clearer: I might sell the recitals and make my own speakers. No need for a SUB.

But that will be a future project.

For now i wanted to know if i could make a simpleconstruction to augment the recitals!

Bas

 

[phase_accurate]

Don't misunderstand me, i KNOW what a TL looks like.

I was sure of that but not all mfgrs implement it the same way (i.e. tapering, back chamber etc).
They once had a cutaway picture of a front firing one on their website. It was quite similar to your 2nd drawing from the left.

Regards

Charles