enclosure suggestions for peerless driver

[GM]

Originally posted by Mikey p
According to GM's recommendation........

I did the work-up in BoxPlot 3.07 because it's the easiest/quickest program I've tried and extrapolated to corner loaded, but HR seems to agree (don't forget to do a 'combine response' in SPL Tools):

GM

[GM]

Originally posted by BWRX

GM, is there any chance you would have some free time to come up with a TQWT alignment for these drivers?

As with the MLTL sim, don't forget to do a 'combine response' in SPL Tools. Note that in both sims the harmonic resonances aren't nearly as bad as predicted, so typical internal damping quells them enough that combined with the XO they're not a problem.

GM

[BWRX]

Looking at the data you posted is still a little foreign but after downloading Hornresp and reading through the help files I gained at least some understanding of what everything means.

Follow along with me to make sure I'm understanding this correctly. For the MLTL the cross-sectional area is constant for S1-S2 and S2-S3 with a total length of 102.16 cm. But S3-S4 necks down from 730.02 sq.cm to 62.06 sq.cm over 0.01 cm and maintains 62.06 sq.cm for 35 cm. In essence, a straight tube/pipe/rectangle for 102.16 cm with a 35 cm long port at one end.

For the TQWT the cross-sectional area starts at 770 sq.cm and goes down to 718.51 sq.cm over 10.16 cm, then down to 77 sq.cm over 194.10 cm.

In either case, where is the driver supposed to be located along the length of the enclosure? Just on the end? I've seen many MLTL enclosures where the line is folded and the driver is located in the middle of the line. How would one do that for either of these designs?

[GM]

Yeah, I much prefer MJK's software for these types of cabs, but now that he no longer offers them I can't recommend them, so HR it is.

Right, TLs are technically constant (zero) taper, ergo MLTL defines a high aspect ratio rectangular or round cab with the driver and vent located somewhere along the line.

Right, (S1-S2) defines the closed end to the center-line of the driver and (S2-S3) the center-line to the 'open' end (i.e. vent tube).

The way HR is programmed, an acoustically insignificant length transition section is required to define a sharp step in the pipe's total length (TL + vent tube).

Right, same scenario as the MLTL except the rectangular cab + vent has been morphed into a single reverse tapered pipe at a 10:1 ratio, though different ratios could be used, but I've had what I consider good success with it, so I don't bother to fix what isn't broke.

WRT driver location, you ideally use what works best for the app. For sub duty, we normally want the max loading (acoustic gain, damping) the alignment has to offer, so this means the driver at the extreme closed end and the vent at the other. This also causes the greatest amplitude harmonic structure, but we can trade some of it for a wider usable BW by 'sliding' the driver down the pipe to find the smoothest, most extended HF response if it's a MLTL or ML-horn, but the TQWT requires its taper ratio be reduced (increase pipe length).

GM