25 cm (10") HiFi woofer with strong drive, extended rear pole plate and 38 mm voice-coil for high power handling. Elastic rubber surround, coated paper cone and magnet vent.Recommended cabinets: Volume/Principle BR-Channel fb 50 l/bass reflex 2 x BR 15.34 43 Hz 70 l/bass reflex 2 x BR 15.34 39 Hz 1 x BR 25.50 (length 7 cm) 100 l/bass reflex 2 x BR 15.34 (length 10 cm) 34 Hz
| Rated power | 100 W |
|---|---|
| Maximum power | 150 W |
| Nominal impedance Z | 8 Ohm |
| Frequency response | fu–5500 Hz |
| (fu: Lower cut-off frequency depending on cabinet) | . |
| Mean sound pressure level | 90 dB (1 W/1 m) |
| Excursion limit | +/−7 mm |
| Resonance frequency fs | 31 Hz |
| Magnetic induction | 1.0 T |
| Magnetic flux | 835 µWb |
| Height of front pole-plate | 7 mm |
| Voice coil diameter | 38 mm |
| Height of winding | 17 mm |
| Cutout diameter | 233 mm |
| Net weight | 3 kg |
| D.C. resistance Rdc | 6.6 Ohm |
| Mechanical Q factor Qms | 1.88 |
| Electrical Q factor Qes | 0.39 |
| Total Q factor Qts | 0.32 |
| Equivalent volume Vas | 121 l |
| Effective piston area Sd | 346 cm² |
| Dynamically moved mass Mms | 38 g |
| Force factor Bxl | 9.2 Tm |
| Inductance of the voice coil L | 1.5 mH |
| Connections | 4.8 x 0.8 mm (+)/2.8 x 0.8 mm (-) |
The strength of horn speakers is, without doubt, in their dynamism. Even short, extremely high peaks and sustained high volumes are reproduced without effort because horns are able to convert electrical energy into sound energy very efficiently. In many cases, this benefit is impaired by the fact that the sound is slightly distorted. This is not the case with the FIESTA 25. Emphasis has been placed in this development on achieving a frequency response curve which is as linear as possible - a key requirement for undistorted sound reproduction and a joy to listen to even if the listening session carries on into the small hours. In order to keep the cabinet down to a reasonable size for living rooms, the bass department does without a tube and instead uses large diaphragms in twin W 250 S - 8 Ohm in a closed compartment.
The striking feature of the FIESTA 25 is the mid-range horn. Here, the DK 8 P - 100 V/15 W horn speaker, based on the pressure chamber principle and borrowed from the public address department, has been applied as a low-impedance version (without the 100 V transformer). It differs from the many other horn speakers of this type which are available on the market by its remarkably good characteristics in the mid-range from 500 to 5000 Hz. Consequently, it is only applied within this range. The tweeter is the HTH 8.7 - 8 Ohm constant directivity horn which has already proved its worth in the MB 208/H kit proposal.
This unusual combination being rather quirky, it was necessary to devise a smart crossover design to achieve the high demands placed on the speaker and satisfy even HiFi standards. Even though the frequency response cannot be as linear as it would be with other loudspeakers, the listener is rewarded with remarkably good sound quality. The FIESTA 25has a pleasant sound ranging from low bass through the clear, well-defined mid-range up to the finest of the higher frequencies. In contrast to standard HiFi speakers, however, this one can easily produce extremely high peak levels and is quite happy to make the walls bulge with continuous, high-level volumes. Provided the listener takes up a suitable central sitting position between the speakers, the well-controlled directivity of these tightly bundled horn speakers allows well-recorded sound to be easily located while ensuring good range layering.
It is fair to say, then that this is a HiFi speaker which will provide very high levels of satisfaction.
