BEYMA 12BR70
BEYMA 12BR70 — 12" / 12 inch · Full-Range Driver · Full-Range / Wideband
125 W AES - 93 dB - 35 – 4000 Hz - 8 Ω
Part no.: 42A-CHS-BB-BEY-0001
Documents
BEYMA 12BR70 — 12" · Full-Range Driver
125 W AES · 93 dB Sensitivity · Frequency range 35 Hz – 4000 Hz
Technical data
- Diameter: 12 "
- Voice coil: 2 "
- Power handling: 125 W AES
- Sensitivity: 93 dB
- Impedance: 8 Ω
- Weight: 3.6 kg
- Mounting depth: 134 mm
- Frequency range: 35 – 4000 Hz
Series: BR · Part no.: 42A-CHS-BB-BEY-0001
Beyma 12BR70: 12" wideband driver with 93 dB, 125 W AES and 8 mm Xmax
A 12" driver that plays from 35 Hz to 4,000 Hz: the Beyma 12BR70 from the BR series is a wideband driver in the sense of bass plus midrange from one cone. Rated at 125 W AES, 93 dB sensitivity and 8 Ω impedance, it is aimed at applications where one driver should cover as much bandwidth as possible before a tweeter takes over. The 2" voice coil and the 3.6 kg weight put it in the class of robust PA woofers.
With Qts 0.5 and Fs 31 Hz the 12BR70 sits in a region that leaves options open. Qes of 0.56 against Qms 4.44 shows that electrical damping dominates, but not as strongly as with pure reflex woofers. The 8 mm Xmax is a lot for a 12" wideband driver and allows clean excursion at low frequencies. Mms of 74 g and BL 12.1 Tm fit a driver that delivers bass with substance and still does not turn sluggish in the midrange. The 134 mm mounting depth is moderate for a 12".
Use and enclosure
The EBP of 55 lies in the region where sealed and bass reflex enclosures both work. For the sealed Butterworth alignment the guideline volume is about 142 l with a corner frequency near 44 Hz, so a large box, but one that needs no tuning effort. Bass reflex works too, but Qts 0.5 is already high enough that you should not tune by rule of thumb; simulate the alignment towards the result you want with the enclosure calculator at 42.audio.
At the top the usable range ends at 4,000 Hz, and a 12" cone already beams strongly there. In a 2-way design the crossover to the tweeter or horn therefore sits below that limit. Compression drivers with matching horns from the Beyma range are the natural treble partners, with the crossover chosen with an eye on the tweeter's lower limit. Le of 0.8 mH leads to a noticeable impedance rise that a passive crossover has to take into account.
What to look out for
- 8 Ω, 93 dB, 125 W AES: easy load, decent headroom for small-scale sound reinforcement.
- Xmax 8 mm: clean bass excursion, unusually generous for a 12" wideband driver.
- Mounting depth 134 mm, weight 3.6 kg: fits shallower cabinets than many 12" woofers.
- Qts 0.5: sealed is straightforward, bass reflex only with simulation.
- Sd 540 cm²: cone area that moves air in the bass.
Frequently asked questions
How big does the enclosure for the 12BR70 need to be?
As a guideline for sealed, about 142 l with a corner frequency of 44 Hz. That equals the Vas of 142 l, because Qts 0.5 calls for a volume the size of Vas in a Butterworth alignment. Smaller boxes raise the corner frequency; the enclosure calculator shows the effect.
Is the 12BR70 suitable for an open baffle?
With Qts 0.5 it sits at the lower edge of what delivers enough bass on an open baffle without equalisation. It works with a large baffle or with electrical bass boost; the 8 mm Xmax helps there.
Which tweeter fits the 12BR70?
A tweeter or compression driver that starts cleanly below 4,000 Hz, so you can hand over the 12" cone before it beams. At 93 dB sensitivity a horn driver keeps up easily in level; matching horns are in Beyma's horns and waveguides section.
Beyma 12BR70: manufacturer, spellings and classification
Beyma and Acustica Beyma refer to the same manufacturer: Acústica Beyma S.L. of Moncada near Valencia, Spain. The 12BR70 is a 12-inch full-range driver from the BR series, available from 42.audio, Beyma dealer in Germany, with datasheet and full specifications in the driver database.
At 42.audio you get the BEYMA 12BR70 with all key data in the driver database and the enclosure calculator. More drivers from this manufacturer: Atlas Beyma.
Thiele-Small parameters
| Nominal impedance | 8 Ω |
|---|---|
| Resonance frequency fs | 31 Hz |
| Total Q Qts | 0.5 |
| Electrical Q Qes | 0.56 |
| Mechanical Q Qms | 4.44 |
| Equivalent volume Vas | 142.0 l |
| Moving mass Mms | 74.0 g |
| Cone area Sd | 540 cm² |
| Linear excursion Xmax | 8 mm |
| Displaced volume Vd | 340 cm³ |
| Force factor BL | 12.1 Tm |
| DC resistance Re | 5.6 Ω |
| Voice coil inductance Le | 0.8 mH |
Enclosure suggestion
The EBP of 55 is in the intermediate range — either works; sealed plays tighter, bass reflex deeper and louder. EBP = fs / Qes = 31 / 0.56
Sealed (Qtc 0.707)
- Enclosure volume Vb
- 142.1 l
- System resonance Fc
- 44 Hz
- Cut-off frequency F3
- 44 Hz
Bass reflex (QB3 after Small)
- Enclosure volume Vb
- 288.3 l
- Tuning frequency Fb
- 25 Hz
- Cut-off frequency F3
- 23 Hz
Vb is the required net internal volume, Fb the tuning frequency of the reflex port and F3 the frequency at which the level has dropped by 3 dB. Calculated approximation after Small. A starting point for simulation, not a finished build plan.
Specifications
| Allgemein | |
|---|---|
| Manufacturer | BEYMA |
| Category | Full Range |
| Series | BR |
| Impedance (Ω) | 8 |
| Power handling (W) | 125 |
| Sensitivity (dB) | 93 |
| Frequency from (Hz) | 35 |
| Frequency to (Hz) | 4000 |
| Abmessungen & Korb | |
|---|---|
| Diameter | 12 |
| Voice coil (inch) | 2 |
| Mounting depth (mm) | 134 |
| Weight (kg) | 3.6 |
| Thiele-Small-Parameter | |
|---|---|
| Re (Ω) | 5.6 |
| Le (mH) | 0.8 |
| Fs (Hz) | 31 |
| Qms | 4.44 |
| Qes | 0.56 |
| Qts | 0.5 |
| Vas (l) | 142 |
| Xmax (mm) | 8 |
| Vd (cm³) | 340 |
| BL (Tm) | 12.1 |
| Mms (kg) | 0.074 |
| Sd (m²) | 0.054 |