Helix PR T25-S – 1″ premium silk dome tweeter
The HELIX PR T25-S is a 25 mm (1″) tweeter from the PURE R-series, which Audiotec Fischer presents as the pinnacle of its PURE speaker line. It is the top tweeter of the PURE range and is built for discerning listeners who want high-frequency reproduction with the finest detail in a vehicle front system.
Tight manufacturing tolerances and a coated silk dome are the basis for its precise and natural treble. A highly efficient neodymium magnet provides consistent linearity of the magnetic flux. The tweeter comes with an anodized aluminum flush-mount housing with a solid mounting ring for concealed installation, plus two different, interchangeable grille designs.
Key Features
- Top PURE tweeter: the high-end tweeter of the PURE R-series.
- Coated silk dome: 1″ / 25 mm dome for precise treble response and natural sound.
- Neodymium magnet: highly efficient magnet for consistent magnetic flux linearity.
- Tight tolerances: manufactured to close tolerances using premium materials.
- Compact design: multiple mounting options for universal installation.
- Flush-mount aluminum housing: anodized housing with a solid mounting ring for discreet installation.
- Two grille designs: standard grilles and exclusive HELIX grilles included and swappable.
- OEM spacers included: supplied with the tweeters to support installation.
- Optional pod: high-grade aluminum tweeter pod PR ATP25 available separately.
Drivers & Construction
- Dome: coated silk dome, cone area Sd 4.9 cm².
- Voice coil: 25 mm diameter.
- Magnet: neodymium.
- Moving mass: Mms 0.3 g.
- Housing: anodized aluminum flush-mount housing with solid mounting ring.
Acoustic Performance
- Impedance: 4 Ω (DC resistance Re 3.4 Ω).
- Sensitivity: 92 dB @ 2.83 V / 1 m; 89 dB @ 1 W / 1 m.
- Frequency response: 2,500 Hz – 25,000 Hz.
- Resonance frequency: Fs 1,400 Hz.
Crossover
- Recommended highpass (minimum crossover frequency): 4,000 Hz at 6 dB/octave; above 3,000 Hz at 12 dB/octave; above 2,500 Hz at 24 dB/octave.
Installation Notes
- Dimensions: outer diameter 37.7 mm, installation diameter 37.7 mm, installation depth 10.6 mm.
- Mounting: flush-mount housings with mounting ring for concealed installation and OEM spacers are included.
- Accessory: optional PR ATP25 aluminum tweeter pod.
Technical Specifications
| Impedance | Z | 4 Ω |
| DC resistance | Re | 3.4 Ω |
| Frequency response | 2,500 Hz – 25,000 Hz | |
| Resonance frequency | Fs | 1,400 Hz |
| Sensitivity |
SPL |
92 dB @ 2,83V / 1m |
| Voice coil diameter | ø | 25 mm |
| Cone area | Sd | 4.9 cm² |
| Moving mass | Mms | 0.3 g |
| Cone material | Coated silk dome | |
| Outer diameter (more data see data sheet) |
ø | 37.7 mm / 1.48″ |
| Installation diameter (more data see data sheet) |
ø | 37.7 mm / 1.48″ |
| Installation depth (more data see data sheet) |
10.6 mm / 0.42″ | |
| Recommended crossover frequencies for the highpass | ||
| Slope | Minimum crossover frequency | |
| 6 dB/Octave | 4,000 Hz | |
| 12 dB/Octave | > 3,000 Hz | |
| 24 dB/Octave | > 2,500 Hz |
Scope of Delivery
2 x Hochtöner PR T25-S
2 x Aluminum flush mount housing
2 x OEM spacer
2 x Standard grille
2 x Exclusive HELIX grille
1 x Mounting material
