Help needed on improving DIY'd Merlin TSM speakers

[daws0n]

Hi,

Last year I was lucky enough to buy a DIY'd set of speakers loosely based / inspired (?) by Merlin's TSMs.

They use the same woofer (MW164) but a different tweet (MDT-39, smaller but sonically very similar to the original MDT-30). I picked them up for a bargain price of £230 (which is not much more than the price of the drivers alone). They sound very very good for the money, though I find myself preferring my smaller Dynaudio 1.1 Contours.... The TSM's have a superior midrange and are clearer with vocals, but they are far less bassy and a little less dynamic in comparison. They seem to have a narrower range and are less defined during busy aggressive passages (metal/hard rock etc..). Though, with "soft" music (ie acoustic/strings/jazz) they take the cake and sound excellent.

Short of adding a sub-woofer, what kind of changes could I make to improve their sound? I am completely new to this but I'd to give it a go if it's not too difficult... I was originally considering selling them on, but the most I've been offered is £210. This would be a very reluctant sale as sound for pound they're worth far more than that in my opinion - despite their shortcomings I wouldn't mind betting I'd have to spend 3-4 times that on a factory made speaker to better them.

Anyways, if anyone has any advice or pointers as to how to get started, I'd really appreciate it

Thanks,
Dawson

Here is some blurb/technical data I saved from the seller's ad when I bought them:

When I first made these they were fitted with the exact same driver arrangement as the Merlin's - a Morel MW164 6.5" woofer and a Morel MDT-30 Tweeter. However after continued listening, tweeking and testing of the speakers I found my prefered match was to use a similar but more compact shielded tweeter from Morel's range (the MDT-39), this allowed me to easily recess the tweeter and accurately time align the drivers (something not possible using the MDT-30 with it's larger faceplate).


The speakers themselves are solidly constructed, using a differing thickness dual layer method with intensive extra internal bracing (all assembled using Marine grade Epoxy Resin - no cheap weak PVA glue used here), they are finished in gloss black with 1/2" solid mahogany side panels. The result of this is the speakers are incredibly strong, solid and inert (with wall thicknesses all 1" at least) a perfect start for producing the very best sound.


Here are some specs:
Sensitivity - 87db/w
Impedance - 8 nominal
Freq Response - 55hz to 20khz +/-3db
Size - 14.5"H x 8"W x 12.5"D


The speakers are single wired (I tried bi-wired/Bi-amped but found no advantage) sealed designs (tried ported but prefered sealed), using symetrical 2nd order (12db/oct) filters on both tweeter and woofer, acoustic damping felt is fitted around the tweeters - this is to help eliminate any possible diffraction effects.

[daws0n]

bump

[PeteMcK]

specs here: http://www.morelhifi.com/products/pdf/mw164.pdf
the obvious thing to do is vent the boxes for more bass if that's what you want; You'd have to find exact internal volume, but Unibox indicates that for ~20L a tuning of ~45Hz will give an F3 of 37Hz with a broad 3 db hump in bass response centred on 77Hz;