Gema — Classic 3-Way Loudspeaker
A large three-way in the spirit of the 1970s: a 12-inch Norex woofer, a sealed dedicated midrange, a soft dome tweeter, and a crossover by Danesian Audio.
about the gema
The Gema is Danesian Audio’s three-way tribute to the big floorstanders of the 1970s — classic proportions, current drivers. The generous enclosure exists for one reason: it gives a 12″ woofer the volume it needs to go deep and stay controlled.
Per cabinet: a 12″ SB34NRXL75-8 woofer, a 4″ SB12MNRX2-25-4 midrange and a 25.4 mm SB26STAC textile dome. Cabinets are walnut veneer matt, supplied without grilles — the Gema was drawn to be looked at.
The midrange SB12MNRX2-25-4
The heart of the Gema's midrange is the 4-inch paper cone SB12MNRX2-25-4, a testament to Danesian Audio's commitment to quality. This driver ensures exceptional midrange clarity with its high efficiency, low moving mass, and linear response.
This driver is designed for dedicated midrange applications. It features a Norex paper cone, known for its natural sound characteristics, and a low damping rubber surround for reduced distortion. The driver's design aims to provide a clear, detailed midrange, essential for the accurate reproduction of vocals and instruments. Midrange is crucial in music as it carries the most critical sounds that the human ear is most sensitive to, including most vocals and many instruments. This driver, with its specialized design for midrange frequencies, is well-suited to ensure clarity and richness in this vital part of the audio spectrum.
the Tweeter SB26STAC-C000-4
The synergy between the articulate midrange and the crisp, open top end is achieved through the 1-inch soft dome SB26STAC-c000-4, complete with a die-cast aluminium faceplate, optimized rear chamber, and full copper cap.
This tweeter, designed for high-end audio applications, is particularly suitable in 3-way speaker systems. Its notable characteristics include a fabric dome for smooth high-frequency response, a die-cast aluminium faceplate for stability, and a vented rear chamber for reduced compression. These features contribute to its excellent performance in delivering crisp, clear highs, making it highly suitable for systems where detailed and accurate high-frequency reproduction is crucial.
The woofer SB34NRXL75-8
The foundation is the SB34NRXL75-8. The manufacturer describes it as a 75.6 mm voice coil on a Norex paper cone, rubber surround, large ferrite motor, cast aluminium chassis — a 12″ driver built to move air.
This 12-inch woofer, designed with a Norex paper cone, offers a balance of rigidity and damping for a clean and detailed bass response. Its large voice coil and optimized motor system enhance power handling and reduce distortion, making it ideal for delivering deep and dynamic low frequencies in the Gema's large 3-way design.
The woofer's characteristics ensure a solid foundation for the Gema's overall sound profile, complementing the midrange and tweeter drivers to create a full, rich audio experience.
Cabinet design
Our well-braced cabinet, a homage to our heritage, features a large slot port tuned to 28 Hz and a sealed enclosure for the dedicated midrange. The quality and value is evident in the design & recommendation to use high-quality 18mm plywood for the speakers, ensuring durability and exceptional sound quality.
Crossover
The Gema crossover is meticulously designed by Danesian Audio, SB Acoustics' danish engineers. This provides the most seamless integration between all drivers and cabinet resulting in the speakers bringing out the intent of the recording by seamlessly integrating with any room you place them in.
Placement
The ideal setup for the Gema speakers includes a spacing of 2.5-3 meters, ensuring ample room for the sound to develop and fill your space. The suggested placement on a stand or plinth, elevated by about 25cm and slightly tilted, is designed to enhance your listening experience.
Specifications
- Frequency Range
- 36 – 24000 Hz
- Sensitivity ( 2.83V / 1m )
- 87 dB
- Nominal Impedance
- 6Ω
- Max SPL
- 108 dB
- Recommended Amplifier
- 50 – 200 W
- Crossover Frequency
- 680/ 3000 Hz
- Enclosure Type
- Bass reflex
- Port tuning Frequency
- 28 Hz
- Drive Units
- SB26STAC-C000-4, 4 inch SB12NRX25-4 & 12 inch SB34NRXL75-8
Tweeter — One SB26STAC-C000-4 per cabinet
A 25.4 mm textile dome on a ferrite motor with an aluminium faceplate. A soft dome suits the Gema: the cabinet and the big paper woofer are voiced warm, and a textile dome finishes that thought.
| Parameter | Value | Parameter | Value |
|---|---|---|---|
| Nominal impedance | 4 Ω | Force factor, Bl | 1.6 Tm |
| Free air resonance, Fs | 750 Hz | Voice coil diameter | 25.4 mm |
| Sensitivity (2.83 V / 1 m) | 91.5 dB | Voice coil height | 1.3 mm |
| Total Q-factor, Qts | 1.12 | Air gap height | 2.5 mm |
| Mechanical Q-factor, Qms | 3.0 | Linear coil travel (p-p) | 1.2 mm |
| Electrical Q-factor, Qes | 1.78 | Magnetic flux density | 1.15 T |
| Effective piston area, Sd | 6.2 cm² | Magnet weight | 0.22 kg |
| DC resistance, Re | 3.2 | Rated power handling | 120 W |
| Voice coil inductance, Le | 0.04 mH | Net weight | 0.53 kg |
| Moving mass incl. air, Mms | 0.3 g |
91.5 dB with a free air resonance of 750 Hz and 120 W rated power handling.
Midrange — One 4″ SB12MNRX2-25-4 per cabinet
A 4-inch Norex paper midrange on a 25.4 mm coil, ferrite motor, cast aluminium chassis — a dedicated midrange rather than a small woofer, in its own chamber.
| Parameter | Value | Parameter | Value |
|---|---|---|---|
| Nominal impedance | 4 Ω | Force factor, Bl | 3.9 Tm |
| Free air resonance, Fs | 63.5 Hz | Compliance, Cms | 1.5 mm/N |
| Sensitivity (2.83 V / 1 m) | 90.5 dB | Mechanical resistance, Rms | 0.4 kg/s |
| Total Q-factor, Qts | 0.32 | Voice coil diameter | 25.4 mm |
| Mechanical Q-factor, Qms | 4.19 | Voice coil height | 9.4 mm |
| Electrical Q-factor, Qes | 0.35 | Air gap height | 5 mm |
| Equivalent volume, Vas | 5.3 L | Linear coil travel (p-p) | 4.4 mm |
| Effective piston area, Sd | 50 cm² | Magnetic flux density | 1.03 T |
| DC resistance, Re | 3.2 Ω | Magnet weight | 0.4 kg |
| Voice coil inductance, Le | 0.15 mH | Rated power handling | 50 W |
| Moving mass incl. air, Mms | 4.2 g | Net weight | 0.92 kg |
90.5 dB and an Fs of 63.5 Hz on a 4.2 g moving mass, which is what lets it keep up with a 12-inch woofer on one side and a dome on the other.
Woofer — One 12″ SB34NRXL75-8 per cabinet
A 12-inch Norex paper cone on a 75.6 mm voice coil, a rubber surround, a large ferrite motor and a cast aluminium chassis. This is the part that makes the Gema look like a 1970s floorstander, because it is the part that made 1970s floorstanders sound the way they did.
| Parameter | Value | Parameter | Value |
|---|---|---|---|
| Nominal impedance | 8 Ω | DC resistance, Re | 6.2 Ω |
| Free air resonance, Fs | 22 Hz | Voice coil inductance, Le | 1.20 mH |
| Sensitivity (2.83 V / 1 m) | 91.0 dB | Moving mass incl. air, Mms | 93.00 g |
| Total Q-factor, Qts | 0.28 | Force factor, Bl | 16.60 Tm |
| Mechanical Q-factor, Qms | 5.50 | Net weight | 8.90 kg |
| Electrical Q-factor, Qes | 0.29 | Recommended port tuning | 22 Hz |
| Equivalent volume, Vas | 205.00 L | Suggested ported volume | 67.89 L |
| Effective piston area, Sd | 508.00 cm² | Suggested sealed volume | 37.77 L |
Fs 22 Hz, 91 dB, a Bl of 16.6 Tm and 508 cm² of piston area. Sensitivity like that is what you get for moving air with cone area instead of excursion.
The cabinets arrive finished
Every cabinet in the photographs on this page is what turns up on the pallet. They are cut, assembled and finished at the same works that makes the drivers, on the same machines, to the same tolerances — so the job in front of you is the acoustics: mount the drivers, wire the crossover, fit the damping.
One finish, chosen to suit the design: walnut veneer, matt, on a set of two cabinets. The Gema is drawn to show its drivers, and the set is supplied without grilles.
Tell us which finish you want when you enquire and we will confirm it against the current factory list before anything is ordered.
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