Small Thor isn't a perfect alignment by any means, but it serves the required purpose. Anyway, go with GM's advice (sorry I haven't been able to catch up with you recently Greg 
I've been spending too much time killing my eyes trying to decipher photographed archive documents. Hope things are as OK as possible at your end though?). As he says, sensible engineering approach (W.O. Bentley would approve) & go with whatever yeilds the largest box. You can always loose what you have too much of. Trying to increase what you don't have in the first place is a little harder. 
Re slightly ragged graphs, I wouldn't get too excited; in practice it'll likely turn out to be overstated.
I've been spending too much time killing my eyes trying to decipher photographed archive documents. Hope things are as OK as possible at your end though?). As he says, sensible engineering approach (W.O. Bentley would approve) & go with whatever yeilds the largest box. You can always loose what you have too much of. Trying to increase what you don't have in the first place is a little harder. Re slightly ragged graphs, I wouldn't get too excited; in practice it'll likely turn out to be overstated.
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Thanks will do so. For an armature like me it is easy to be tempted of ruler flat response and deep LF action. Therefore I´m very grateful for the feedback I get from all of you who are much more experienced!
Interesting to see how the TS parameters differ depending on the source.
HiVi D6.8 Thiele Small:
An externally hosted image should be here but it was not working when we last tested it.
I think I have to simulate with the other sets of TS-parameters just to see how it effects the response but that is for another evening.
(sorry I haven't been able to catch up with you recently Greg
Re slightly ragged graphs, I wouldn't get too excited; in practice it'll likely turn out to be overstated.
No problemo, work takes precedence unless you're one of the 'landed gentry'.
Regardless, as bad as my reply rate is, I can't 'cast any stones'. Anyway, got your recent emails and will respond as soon as I get done with all the 'work' related ones. Samo-samo unfortunately, but that's better than I've been on way too many occasions.
Right, not mention our falling hearing acuity below our head transfer function around 800 Hz.
GM
Been there, done that.
Way back when I was keen of hearing, I became obsessed with trying to make a compression horn as 'open' (no audible horn 'color') and two horns as coherent (no audible time delay between them) as a 'full-range' driver. It was a very enlightening experience in so many ways.With low efficiency speakers though, so much of the LF through lower mids gets 'lost' in the system's high noise floor that at worst, those phase 'bumps' add a bit of euphonic distortion compared to the damped 'flat as a billiard table' response that makes a sim look so good.
Yeah, I 'ran the numbers' and not surprisingly (to me), zaph's yields the largest cab, though not as much more than official as is typical. Indeed, if you used them they would be good enough for (ML) TLs.
Anyway, if you want to better damp them without resorting to high stuffing densities, then adopt an 'acoustic solutions for acoustic problems' design attitude, or in this case, make ML-horns which will cause the vent's harmonics to decay away faster. It increases build complexity, but there's not many 'free lunches' in audio design.
Or do as I do/recommend to save building time/effort when vents are either large and/or long, fire them out the bottom and if the floor's not heavily carpeted, add an absorber to attenuate its upper harmonics.
GM
I´m not sure I´m familiar with the term ML-horn, could you please give me a link to such project or explanation?
Do you mean something like this?
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
Kind regards
/Forsman
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pics for 
In my little corner out here on the fringe of the audio world, any cab that expands is a horn and MJK chose to call a vent's output as mass loading (ML), ergo I call an expanding cabinet with a vent at the big end a ML-horn whereas he calls it a ML-TQWT whether it expands or contracts, so is the most common moniker.
Correct, just make the feet adjustable to fine tune the vent by externally mass loading it. That, or you can use different size/shape cone plugs.
GM
Correct, just make the feet adjustable to fine tune the vent by externally mass loading it. That, or you can use different size/shape cone plugs.
GM
No one can call me fast…
Well, now I have reconsidered and simulated a ML TQWT. And with some elaboration with the internal position of the end of the port I’ve got a very flat response curve with pretty little stuffing. The bass is rolling off more rounded than my earlier simulations but not as round as yours GMs. My intension is to place them very far from the back wall, around 3-4 meters. Maybe this alignment could be a functionel compromise?
Kind regards
/Forsman
Well, now I have reconsidered and simulated a ML TQWT. And with some elaboration with the internal position of the end of the port I’ve got a very flat response curve with pretty little stuffing. The bass is rolling off more rounded than my earlier simulations but not as round as yours GMs. My intension is to place them very far from the back wall, around 3-4 meters. Maybe this alignment could be a functionel compromise?
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
Kind regards
/Forsman
Hmm, that far away and you may want to consider a flatter response to a lower F3, say in-between this one and your max flat alignment. Really, oft times such a positioning requires as much cab gain as you can afford in space/$$$ since it can be close to a 2pi loading, not to mention that even small positioning adjustments can audibly change its response due to the room's 1/2 WL harmonic structure same as when the listening position is well away from any walls/corners.
If both are well away, then getting them right is no trivial pursuit if the room isn't square/rectangular and sealed well enough to easily calculate its modes and why digital room correction is a boon to anyone serious about high SQ HIFI/HT.
GM
If both are well away, then getting them right is no trivial pursuit if the room isn't square/rectangular and sealed well enough to easily calculate its modes and why digital room correction is a boon to anyone serious about high SQ HIFI/HT.
GM
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