Posted by Wayne Parham on May 20, 2002 at 23:10:35

In Reply to: Question for Wayne posted by Wasteh202 on May 20, 2002 at 22:18:40:

I wouldn't put a JBL 2226 in a Theater Series four π cabinet, because it's too large. The cabinet for a JBL 2226 should be no larger than roughly half the size of the Theater Series four π, unless you're doing something like an EBS, which is not the best application for a 2226. The model that uses the JBL 2226 is the Professonal Series four π loudspeaker.

The Theater Series four π Speaker goes deeper but has rising response in the bottom octave. Response is flat from (f3) 50Hz up, but has useful response to below 20Hz. It rises at 12dB/octave starting about 16Hz, so it can really go deep with room lift, and the slope is complementary.

Another characteristic of the Theater four π is the midwoofer's narrowing directivity making response rise 6dB in the octave just under crossover to the tweeter. When it is placed in a room corner, then the rest of the audio range is forced into approximately the same directivity pattern, and this equalizes response. Floor placement against a back wall comes close.

The JBL 2226 used in the Professional Series four π speaker does not have this kind of rising response. It has flat response on-axis, even through the region where DI begins to narrow. This is because the midwoofer has falling power response that is roughly equal to its rising DI.

The Professional Series four π speaker sounds more natural in large spaces. If it radiates into a constrained space, the bass will be a little over-emphasized. Tuning is slightly underdamped, so it doesn't sound boomy when used in smaller rooms or placed in corners, but it is best used used in larger environments radiating into quarter-space.

One more thing I should mention is the fact that the JBL 2226 uses a shorting ring. This dramatically reduces distortion, especially at midrange frequencies above 100Hz.