Waveform MC.(egg-shaped speaker)(Evaluation)

Waveform produced high-end speakers for about 15 years. Over the last few years the midrange and tweeter of the speakers were enclosed in an egg-shaped pod. The MC was the company's lowest-priced product ($1,085 each, with MC tower stand $495, grille [not tested] $145 each, shelf mounting board [not tested] $185, and omnimount wall mount adapter [not tested] $135). Essentially, the MC is the egg-shaped pod of the larger model without the woofer box. The 6.5-inch midrange of the larger unit was replaced by a woofer of the same size, and a port was added to the rear. The-soft dome tweeter was the same unit used across the line.

The egg was made of a thin-wall aluminum casting with a sandwich layer of open-cell, natural rubber glued to the entire inside cavity. Rapping the cabinet while listening for resonances produces virtually no audible response. I have never experienced anything like it.

The object of shaping the enclosure as an egg is to minimize reflections from the baffle and maximize dispersion. This is not a gimmick. Using the ETF 5 software I got the best measurements I have seen. The highlight was the energy/time curve, which shows energy coming from the speaker and the room after the original impulse. The energy comes down very quickly, by 50dB in 4msec. Known room reflections then followed after this. One normally sees spreading in the initial impulse or a rise in the residual noise floor during the period before the arrival of the room energy, but not with the Waveforms.

In the frequency domain things are also excellent, with a measured response of +/- 1.5dB measured 15 degrees off axis. On-axis, the response rose about 3dB from 5kHz to 20kHz. At 30 degrees off axis the response declines 4dB from 5kHz to 20kHz. At 30 degrees off axis on sees about a 1dB shift around 2kHz. That's a very, very small sign that the woofer is becoming slightly directional. Other speakers can show much more dramatic effects.

Waveform published slightly tighter curves measured anechoically in the NRC of Canada. I have no doubt that the NRC results are more accurate than my gated measurements, which I took in my living room using a lap-top sound card and the microphone ETF supplies with its system. Others have measured this unit independently and they all come to the same conclusion. It is flat, flat, flat, and this holds true over a significant change in horizontal axis.

The speaker's preferred axis is just below the tweeter but there is no need to get to worried about this; indeed, moving the microphone from below to above the egg does not make a big difference in the response. Staying between the woofer axis and slightly above the tweeter costs a 1 to 2dB dip in the 2000Hz to 3500Hz region. Outside this range the dip grows and the high end above 5kHz starts to move down a couple dB. The 4th-order Linkwitz-Riley crossover at 2200Hz keeps the interaction between the drivers constrained to a small frequency band, as we demonstrated in the vertical response profiles. The close proximity of the drivers also helps reducing variations in frequency response with changes in vertical height.

With ears replacing microphones and music replacing maximum likelihood sequences it is still easy to hear what the egg and the high-order crossover are doing. It matters little if you sit or stand, as the perceived response changes little. Walking around the front of the egg even at very large angle relative to the front also results in relatively small perceived response changes.