changing a fullrange.....

[Lostcause]

Hi Chaps, OK I know I'm going to get shot for this but as my Dad used to say...if you don't ask.....

I currently have a MK MLTL with the 207's in and after months of playing around with these puppies I still find it difficult to get good - wide- bass response.

It seems to be the very low listening levels and an 'odd' shaped room that produce a limited sweet spot that is still bass shy.

Oh, I've tried everything to improve it...BSC...No BSC....Stuffing...No stuffing...etc, etc.

So, the question is.....Can I introduce another driver in the same box, with obvious internal alterations of course, and could anyone make some suggestions to try? I was just going to add an active sub but placement is an issue and I was hoping for a more elegant solution.

Be gentle with me please, this is my first speaker project.

[adason]

just get the subwoofer

[roger_lew]

You could go bipole but not in the same box because you would need to double the cross sectional area of your TL. Baffle step would be eliminated mechanically, plus you would have the extra output of additional drivers.

There is a lengthy discussion in the diyAudio Reference Fullrange Project thread which you might find helpful.
diyAudio Full Range Reference Project

RL

[rjb]

Try putting in a small (2 or 3 ohm) series resistor. Nelson Pass has writeup of this. Mind the limited cone excursion though, which will limit volume level.

[Lostcause]

Originally posted by rjb
Try putting in a small (2 or 3 ohm) series resistor. Nelson Pass has writeup of this. Mind the limited cone excursion though, which will limit volume level.

Tried this as well....

The thing is I dont need volume at all, this is what seems to limit the bass response.

Looks like the active whoofer is the only option then.

Thanks for the input anyway chaps

[roger_lew]

If you are always listening at low volume it could be a problem of perception. Equal loudness contours have larger db differences at low volumes between low frequencies and higher frequencies than equal loudness contours at higher volumes. http://en.wikipedia.org/wiki/Equal-loudness_contour

You may need a frequency response with way more bass then most of us would prefer at our "normal" listening levels.

Regards,
RL

[tinitus]

I guess what you really need is a small amp with "high" output impedance

[Lostcause]

Originally posted by tinitus
I guess what you really need is a small amp with "high" output impedance

Does a T-amp qualify?

[tinitus]

Its a small classD amp, right - if thats your amp I think you could solve some of your problem with tweaks that "tames" high frequencies, cables, cork feet under your CD, etc.

[Lostcause]

Originally posted by tinitus
Its a small classD amp, right - if thats your amp I think you could solve some of your problem with tweaks that "tames" high frequencies, cables etc.

Well currently it has all the stuffing removed (apart from some felt to deaden the cab) phase plugs and 3 ohms of 1mm nichrome wire on each channel. It's the best I've had yet but still only hits a limited sweet spot.

No BSC as it appears to kill the clarity at low levels... excellent on mid to high levels though.

The room really doesn't help either.