Hyperwhamos

The combination of Whampipes and original bandpass subwoofers was called the Hyperwhamodyne system. While in theory the overlap of the 70Hz rolloff of the tapered pipes and the 110Hz upper cutoff of the subs should have created great problems, most listeners preferred the Whampipes with the addition of the subwoofers. The woofers had been wired out of phase with the vented tower design, but they were now wired in phase with the pipes, which seemed to create some bit of smoothing in the overlap region. The new fullness of the lower midrange seemed to work pretty well with the presence obtained by use of a 6 mfd cap on the titanium tweeter. Here's some thoughts on further developments.
These could be very satisfying  with a Paraglow with the KR single plate 2A3.

Looking back-
Overall the Whamos were a very pleasant surprise, considering how many conventional rules were broken in their development. Their deep bass and good top end extension was a refreshing change from the rolled off deep bass and dull highs of many other efficient systems, and their lack of "honk" compared to marginal horn designs was a definite plus. The sense of depth of image was excellent, and the scale of instruments was very effective.

Minuses? Of course there are some, like every speaker system ever designed.
Here's some areas that deserve further development:

The bandpass subwoofer exhibits a suckout at 70 Hz. Various stuffing schemes were tried, but this issue was never completely resolved. There are also a couple of  peaks at 55 Hz and 110 Hz. They can be a bit boomy in some rooms. The same woofers used in a conventional downfiring vented box of about 5.3 cu.ft. and crossed over at 80Hz were smoother, but lacked the efficiency necessary to keep up with the Whampipe, and required biamping.

96 dB sensitivity with a subwoofer in the system means that you really need at least 4 watts to run the full system. One very successful solution was to biamp using a pair of Afterglows on the towers and the original S.E.X. amps with their feedback loop removed on the subs. The new ParaS.E.X. kit will also now work well fullrange at its current 5W power rating. Amps in the 15-25W class hit pretty amazing levels!

The crossover is a real "taste thing". The 6 mfd cap gave a presence, but also a bit of edge at times. A 1.5 mfd cap is very smooth, but can sound recessed with some music. It's worth experimenting with a range of values.

The large array sounds better to Doc's ear at some distance, say 10-15 ft or more. These are not speakers for tiny rooms.

It is a little tricky to get a very wide soundstage. Cross aiming the speakers to focus at a point ahead of the listening position is helpful. Next Page