On the Bench
THD+N measurements were taken at 1 foot from the respective drivers. Bandwidth for distortion measurements was 10 Hz - 80 kHz.
At 50 Hz and 100 dB output, the mid/woofers have a very acceptable amount of distortion for such small speakers.
At 1 kHz, still measuring from the mid/woofers, THD+N was only 0.22%
And, at 10 kHz, measuring from the tweeter, also a very low amount of THD+N.
The Room Response for the 2515 was measured at three distances: 1 foot, 1 meter, and 2 meters, to show the increasing effect of the room and the decrease in SPL at the microphone. The response was reasonably flat down to about 50 Hz, where it rolled off sharply. This is why I set the crossover in the SSP to 50 Hz. However, when I just listened to two-channel stereo, I did not use any crossover, so the 2515s ran full-range.
The measured impedance stays mostly between 6 ohms and 12 ohms, with the electrical phase being ± 400. This should be a very easy speaker to drive with just about any amplifier, including those in inexpensive mass market receivers.
Since the MiniMe is a very small subwoofer, I decided that it would not really be very fair to run the usual tests down to 20 Hz, so I will be testing the THD+N for this category of subs at 40 Hz, and then a Room Response that covers all the frequencies.
For the MiniMe, there was 11% THD+N at this frequency, and 100 dB output (at 1 foot). It's a small sub, so I expected a reasonably high number.
The Room Response at the various distances indicate that the MiniMe rolls off sharply below 40 Hz. If you want response down to 30 Hz, either get a bigger subwoofer, or use an EQ to bring the response above 40 Hz down to the level between 30 Hz and 40 Hz. For myself, I would use a larger sub, because I want a good response down to 20 Hz.
PN-2515 LCR speakers are a fine addition to the Earthquake Sound line. They have a clear,
detailed sound with a very natural timbre. Using identical speakers all the
way around does have its advantages. The MiniMe P8 subwoofer is adequate for
many applications, especially if you don't watch too many action movies, but
if you like things to really go kaboom in your home theater, you would be
better off going with one of their larger subs.
- John E. Johnson, Jr. -