Test Bench: Paradigm Signature Speaker System
In the lab
Frequency response (at 2 meters) front left/right 90 Hz to 18.1 kHz ±3.4 dB center 90 Hz to 19.6 kHz ±3.1 dB surround 104 Hz to 9 kHz ±5.0 dB subwoofer 24 Hz to 75 Hz ±2.2 dB
Sensitivity (SPL at 1 meter with 2.8 volts of pink-noise input) front left/right 85 dB center 85 dB surround (dipole) 87 dB
Impedance (minimum/nominal) front left/right 3.5/10 ohms center 3.7/10 ohms surround 3.3/6 ohms
Bass limits (lowest frequency and maximum SPL with limit of 10% distortion at 2 meters in a large room) front left/right 80 Hz at 87 dB center 80 Hz at 89 dB surround 80 Hz at 80 dB subwoofer 20 Hz at 98 dB SPL 109 dB average SPL from 25 to 62 Hz 110 dB maximum SPL at 32 Hz bandwidth uniformity 99%
All of the curves in the frequency-response graph are weighted to reflect how sound arrives at a listeners ears with normal speaker placement. The curve for the left/right front channels reflects response of the Signature S1 averaged over a ±30° window. The center-channel curve reflects response of the C1 averaged over ±45°, with double weight directly on-axis of the primary listener. The surround-channel curve shows the response of the ADP1 dipole averaged over ±60°.
All satellite speakers were measured on a 6-foot stand which gives anechoic results to approximately 200 Hz. All measurements are taken at a full 2 meters, which emulates a typical listening distance, allows larger speakers to fully integrate acoustically and, unlike near-field measurements, fully includes front panel reflections and cabinet diffraction.
Measurement and subjective evaluation of this system were done without grilles. Without the grille, the S1 satellite has a smooth bass-to-treble balance and flat response, marred only by a modest 2 dB elevation between 4 kHz and 10 kHz. Installing the grille results in a large but narrow 10 dB notch at 12 kHz and a 7 dB peak at 9.3 kHz; though these would probably be difficult to detect. Interestingly, the center channel exhibits a similar characteristic with its grille.
The C1 center channel has no off-axis lobing, but a 3 dB depression from 900 Hz to 2.1 kHz and the 3 small peaks at 4, 6 and 9 kHz can be seen in all traces. Both the S1 and C1 respond with suspension noises when driven into overload. The ADP1 has a strong 800 Hz dipole notch directly on axis and the "ripply" averaged response is both representative and desirable for bidirectional surround speakers.
The Signature Servo subwoofer bass limits were measured with it set to maximum bandwidth and placed in the optimal corner of a 7,500-cubic-foot room. In a smaller room users can expect 2 to 3 Hz deeper extension and up to 3 dB higher sound-pressure level (SPL).
Dynamically, this is the best subwoofer I've seen in some time. It will deliver 109 dB at every frequency above 25 Hz, and can do a real 20 Hz with less than 10 % distortion. 16 Hz at 88 dB SPL is "almost" do-able at that distortion level, but sustained input of such a low note causes the effects of its protection circuitry to become audible.
Regarding its crossover: Although the half-power point of 75 Hz with the crossover set to 150 Hz seems limited, it is also true that the fall off rate is only 3 dB for the first octave, so the unit has usable output to 150 Hz. At the lowest setting (30 Hz) the actual roll off frequency is 45 Hz, but there is virtually no level/crossover interaction over the full operating range of the crossover control. The Bass Contour control, when set to its maximum 6 dB marking, delivers 5.7 dB at a center frequency of 60 Hz.