B&C DE618TN – Low-Distortion 1.4-Inch Titanium Compression Driver with Redesigned Diaphragm and Ferrite Motor
The B&C DE618TN is the ferrite-motored version of B&C’s premium DE680TN neodymium driver — and it carries a diaphragm that B&C has completely redesigned for lower distortion and smoother high-frequency response. With 108 dB sensitivity, 80 W AES power handling, a 65 mm voice coil, titanium diaphragm with bent edge voice coil former and new dome geometry, a shorting copper cap, and a 1.2 kHz recommended crossover, the B&C DE618TN delivers the same headline performance as the neodymium DE610 from a ferrite motor platform that costs less to manufacture.
The redesigned diaphragm is the engineering story that separates the B&C DE618TN from the other 65 mm coil 1.4-inch drivers in B&C’s range. B&C states it directly: the new diaphragm incorporates a bent edge voice coil former, new dome geometry, and new surround geometry. These modifications combine to better control diaphragm displacement and deformations, resulting in lower distortion and smoother frequency response above 10 kHz.
That last detail matters. The 10 kHz region is where titanium diaphragms typically produce their most problematic resonant behaviour. The B&C DE618TN’s redesigned dome and surround specifically target this region, producing cleaner output in the upper treble where conventional titanium diaphragms are at their worst. For system designers who want titanium’s projection and detail without the harshness titanium can produce above 10 kHz, the B&C DE618TN is the driver that addresses the issue at the diaphragm level rather than relying on DSP correction.
The ferrite motor matches the neodymium DE610 on every headline specification — 108 dB, 80 W AES, 1 kHz – 18 kHz, 1.2 kHz crossover — at the same 3.8 kg weight and 156 mm body diameter. Available in 8 and 16 Ω with a user-replaceable titanium diaphragm (part number MMD25BTN8M).
Design and Construction of the B&C DE618TN
The B&C DE618TN uses a 65 mm (2.5-inch) aluminium voice coil driving a redesigned titanium diaphragm through a 1.4-inch (36 mm) exit throat. The 65 mm coil matches the DE602 and DE610 in diameter, providing the same thermal capacity and the same 80 W AES power handling across all three drivers.
The diaphragm is where the B&C DE618TN introduces its most significant engineering innovation. The bent edge voice coil former changes how the coil attaches to the diaphragm dome. In conventional compression drivers, the former meets the dome at a sharp junction that creates a stress concentration point — a location where the diaphragm is prone to deformation under high excursion. The bent edge design spreads this transition across a wider area, reducing localised stress and allowing the dome to move more linearly.
The new dome geometry works in conjunction with the bent edge former. B&C redesigned the dome profile to control the breakup modes that titanium exhibits at high frequencies. Conventional titanium domes break up in patterns that produce sharp resonant peaks — the bright, sometimes harsh character that titanium is known for. The B&C DE618TN’s dome geometry redistributes these breakup modes, smoothing the response above 10 kHz where conventional titanium drivers are most problematic.
The new surround geometry completes the redesigned diaphragm system. The surround — the flexible ring that connects the dome to the driver chassis — affects how the diaphragm moves at its outer edge. The revised surround design provides more controlled compliance, supporting the dome geometry’s improved breakup behaviour and contributing to the overall reduction in distortion.
Together, these three modifications — bent edge former, new dome geometry, new surround geometry — produce a titanium diaphragm that sounds more refined than conventional titanium while retaining the stiffness, detail, and projection that make titanium the preferred material for professional live sound. The B&C DE618TN doesn’t sacrifice titanium’s character. It cleans it up.
The magnetic circuit uses a ferrite magnet with a shorting copper cap, producing 1.65 T of flux density. The ferrite motor produces slightly less flux than the neodymium DE610’s 1.75 T, but the headline performance specifications — 108 dB sensitivity, 80 W AES — match exactly. The 0.15 mH inductance with the copper cap is identical to the DE610, confirming that the electrical behaviour and crossover compatibility are the same between the two drivers.
Ferrite motors are physically larger than neodymium for equivalent flux, but B&C has engineered the B&C DE618TN’s motor to fit within the same 156 mm body diameter and 3.8 kg weight envelope as the neodymium DE610. The slightly lower flux target (1.65 T vs 1.75 T) makes this possible — by accepting a modest reduction in magnetic circuit intensity, the ferrite motor achieves near-identical size and weight while offering lower material costs.
At 3.8 kg, 156 mm overall diameter, and 66 mm depth, the B&C DE618TN is essentially identical in physical dimensions to the DE610. One millimetre of additional depth is the only measurable difference. Four M6 mounting holes on a 102 mm bolt circle match the standard 1.4-inch professional pattern.
Performance and Applications for the B&C DE618TN
The B&C DE618TN delivers 108 dB sensitivity across a 1 kHz – 18 kHz bandwidth with a recommended crossover frequency of 1.2 kHz. These specifications match the DE602 and DE610 exactly. On a standard sensitivity measurement, all three 65 mm coil 1.4-inch titanium drivers in B&C’s range produce the same output per watt.
The difference is in the distortion performance, specifically above 10 kHz. The B&C DE618TN’s redesigned diaphragm produces measurably lower harmonic distortion in the upper treble compared to conventional titanium designs. For the listener, this means the characteristic titanium brightness is still present — the detail, the projection, the transient snap — but the harshness that sometimes accompanies conventional titanium in the 10–15 kHz region is reduced.
This distortion reduction has practical consequences for system tuning. In systems with DSP, the B&C DE618TN requires less corrective EQ in the upper treble — the response is naturally smoother above 10 kHz, giving the system designer a cleaner starting point for voicing. In systems without DSP, the improvement is even more significant — the driver sounds more balanced and less fatiguing over extended listening periods because the diaphragm itself generates less distortion rather than relying on processing to compensate.
The 80 W AES / 160 W program power handling matches the DE602 and DE610 as the highest in B&C’s 1.4-inch range. The 65 mm coil’s thermal capacity sustains this power rating through extended operation, and the redesigned diaphragm’s improved displacement control means the B&C DE618TN maintains its lower-distortion advantage even at high power levels where conventional diaphragms would produce increasingly nonlinear behaviour.
The 1.2 kHz recommended crossover enables early woofer-to-horn handoff for optimised directivity control. The B&C DE618TN produces authoritative output from 1.2 kHz upward with the same sensitivity and bandwidth as the neo alternatives.
The ferrite motor is the cost advantage. Neodymium is a rare earth metal with volatile pricing and supply chain concerns. Ferrite is a stable, widely available magnetic material with predictable costs. For builders producing speaker systems at volume — where per-unit driver cost affects the final product price — the B&C DE618TN delivers DE610-class performance without the neodymium premium. The 3.8 kg weight matches the DE610 exactly, so the cost saving comes without a weight penalty.
The 8 and 16 Ω impedance variants provide the same multi-driver flexibility as the DE610. Line arrays, multi-driver HF sections, and systems standardising on one driver model across configurations all benefit from the 16 Ω option.
Ideal applications for the B&C DE618TN include:
- Professional two-way and three-way systems where lower distortion above 10 kHz matters
- Touring speaker systems seeking DE610-class performance at lower driver cost
- Line arrays using the 16 Ω variant for multi-driver HF configurations
- Installed sound systems where ferrite motor cost stability reduces long-term procurement risk
- Two-way systems crossing over at 1.2 kHz for optimised directivity control
- Volume production runs where per-unit driver cost affects the product pricing
- Systems running without DSP where the smoother diaphragm reduces the need for corrective EQ
- Applications where the redesigned diaphragm’s lower distortion justifies the choice over the DE602
Specifications – B&C DE618TN
- Throat Diameter: 36 mm (1.4 in)
- Nominal Impedance: 8 Ω
- Minimum Impedance: 7.3 Ω
- Nominal Power Handling: 80 W
- Continuous Power Handling: 160 W
- Sensitivity: 108 dB
- Frequency Range: 1 kHz – 18 kHz
- Recommended Crossover: 1.2 kHz
- Voice Coil Diameter: 65 mm (2.5 in)
- Winding Material: Aluminium
- Inductance: 0.15 mH
- Flux Density: 1.65 T
- Magnet Material: Ferrite
- Diaphragm Material: Titanium (redesigned dome, surround, and bent edge former)
- Replacement Diaphragm: MMD25BTN8M
- Available Impedances: 8 Ω, 16 Ω
- Net Weight: 3.8 kg (8.38 lb)
Mounting Information – B&C DE618TN
- Overall Diameter: 156 mm (6.14 in)
- Depth: 66 mm (2.6 in)
- Bolt Pattern: Four M6 holes on 102 mm (4 in) bolt circle, 90° apart
Conclusion – B&C DE618TN Compression Driver
The B&C DE618TN is the most refined titanium 1.4-inch compression driver in B&C’s 65 mm coil class. The completely redesigned diaphragm — bent edge former, new dome geometry, new surround geometry — delivers lower distortion and smoother frequency response above 10 kHz than the conventional titanium diaphragms used in the DE602 and DE610. The result is titanium that sounds detailed and projecting without the harshness that conventional titanium can produce in the upper treble.
The ferrite motor matches the neodymium DE610 on every headline specification — 108 dB, 80 W AES, 1.2 kHz crossover, same weight, same body, same bolt pattern — while offering lower material costs and more stable procurement pricing. For volume production and cost-conscious specifications, the B&C DE618TN delivers equivalent performance without the neodymium premium.
The redesigned diaphragm and the ferrite motor together create a compelling proposition: better distortion performance than the DE610’s conventional titanium diaphragm, at lower driver cost, with the same sensitivity, power handling, and system compatibility. The B&C DE618TN doesn’t compromise — it solves two problems simultaneously, delivering a more refined diaphragm and a more cost-effective motor in the same 3.8 kg, 156 mm package.
For touring systems, installed sound, line arrays, volume production, and any application where a 1.4-inch titanium compression driver needs to deliver 108 dB with the lowest distortion and smoothest upper treble available in B&C’s 65 mm coil class, the B&C DE618TN is the driver that cleans up titanium’s roughest edges while keeping the projection and detail that make titanium the professional standard.
VIEW MORE B&C PRODUCTS HERE.
About B&C Speakers S.r.L.
B&C Speakers products are built in Bagno a Ripoli (Florence), Italy., ensuring high quality products to suite your speaker building requirements. Their 10,500 square meter facility incorporates highly sophisticated automation and quality control. Over the years they become one of the world leaders in the Professional Audio market, a brand recognized everywhere as a premium product that offers excellent value to the consumer.
