Mark Audio Alpair 12P Full Range Speaker Driver

The MarkAudio Alpair 12P is a highly sensitive 8-inch, paper-cone full-range driver favored by audiophiles for its natural midrange, dynamic responsiveness, and lack of crossover distortion.

 

 

The Markaudio Alpair 12P is a premium, high-efficiency 8-inch paper cone full-range speaker driver designed for purist audiophile systems. Created by designer Mark Fenlon, it aims to deliver highly detailed, dynamic, and full-range audio from a single cone without utilizing phase plugs, co-axial center tweeters, or whizzer

 

Key Specifications

• Nominal Diameter: 8 inches
• Sensitivity: ~91.7 dB
• Frequency Range: 40 Hz to 22,000 Hz
• Nominal Power Handling (RMS): 30 Watts
• Resonance Frequency (\(F_{s}\)): 42 Hz
• Total Q Factor (\(Q_{ts}\)): 0.285
• Maximum Linear Excursion (\(X_{max}\)): ± 5.4 mm (1-way)

 

Design & Construction Highlights

• Custom Paper Cone: Features a shallow-profile, lightweight natural paper cone (21-mm deep) that improves wide sound dispersion and minimizes moving mass.

 

• Advanced Voice Coil: Employs a custom Copper-Clad Aluminum Wire (CCAW) voice coil wrapped in an aluminum/paper matrix with a low-mass, thin-walled, vented body.

 

• Advanced Suspension: Utilizes a special progressive-rate rear spider designed by Matsubara San to preserve high linearity across a long mechanical throw.

 

• Semi-Free-To-Air Profile: Designed as a mechanically unconstrained single-cone front arrangement where the ultra-thin front surround supports almost no cone load.

 

• Chassis: Built using a self-damping reinforced polymer basket to stop frame vibrations from coloring the output signal.

 

 

 

Enclosure and Amplifier Pairing

Because it is a low-Qts driver with high conversion efficiency, it requires intentional cabinet matching.

• Enclosure Types: It excels in large, acoustically efficient enclosures. It is highly popular in Pensil designs, horns, and Folded Voigt Pipes (FVP). Smaller vented stand-mount boxes (approx. 16–17 Liters) work but will offer limited low-frequency extension.

 

• Baffle Step Compensation: Due to its extremely flat native frequency response, builders often need to implement Baffle Step Compensation (BSC) to prevent mid-to-high frequencies from overpowering the bass when placed in wider cabinets.

 

• Amplification: Requires very modest power to perform beautifully. It pairs exceptionally well with warm solid-state amplifiers, Class D modules, or tube gear that matches well with higher output impedance.

 

 

Key Characteristics

• Sound Signature & Voicing: The custom paper cone provides a vintage, controlled warmth. Users consistently praise its ability to image beautifully, providing terrific separation between instruments and incredibly natural vocals.

 

• Efficiency: With a manufacturer sensitivity of roughly 91.7 dB, it is noticeably easier to drive than other Alpair models, making it a great candidate for lower-powered tube amps.

 

• Mechanical Design: It features an unconventional "semi-free to air" suspension design without a traditional spider. This allows the lightweight, shallow cone to move highly freely, resulting in incredible transient speed and micro-detail.

 

Strengths & Weaknesses

• Strengths: Outstanding midrange transparency and vocal presence. It has enough high-frequency extension to handle treble duties on its own for most listeners, doing away with the need for a tweeter.

 

• Weaknesses/Limitations: Opinions on the bass and extreme highs are mixed. Some users on diyAudio report that the bass lacks deep sub-bass extension in standard enclosures. High frequencies can also sound slightly soft or "rolled off" to those used to metal-domed tweeters, and it requires clean, low-distortion amplification to prevent it from sounding fatiguing.

 

Enclosure and Build Notes

Because it is a full-range driver, the cabinet is everything. To maximize its capabilities, the driver demands a well-designed, acoustically efficient enclosure (such as large ported designs, folded Voigt pipes, or Pensil cabinets) to help bolster its lower-frequency response. Users note that break-in time is crucial; the rubber surround and suspension loosen up after a few weeks, which significantly improves both bass response and high-frequency resolution

 

Full Description:

The Alpair 12P is the largest full-range driver produced by Markaudio. This driver is a development unit following on from the original metal coned Alpair 12 produced in 2009/2010. Several major design changes make this Alpair radically different from the original in terms of its operation and performance.

Brief Markaudio Alpair series drivers are totally custom designed and built. All components (apart from the magnet) are individually designed and engineered with their own tooling and mould making sets. Alpair drivers are made by highly skilled engineers, they arenʼt “mass produced”.

 

Key Features:

The change to a custom paper cone with a more shallow profile reduces mass and increases dispersion performance. The new cone is only 21-mm deep compared to the metal unit at 26- mm. The 12P employs and new custom CCAW coil with an aluminium/paper wrap, vented, lowmass thin-walled body. The spider is particularly special. Designed by Matsubara San, it employs a new long throw profile set together with a ribbed body to maintain linearity. The front suspension remains the same as the previous model; A design by Lu Yi Ping, its ultra thin wall doesnʼt support the cone. In terms of mechanical load performance, the 12P remains a single semi-free to air driver, possibly a unique design in its class.

 

Performance

The 12P remains pure to designer Mark Fenlonʼs current criteria which is to make purist, single cone drivers that are full-range capable without the use of phase plugs, co-axial centre tweeters or whizzers. The 12P is 92dB efficient (1w/1m), operating to 22 kHz (-3dB) and having a resonance frequency of 42Hz (+/- 2Hz). The 12Pʼs power-train (cone, cap, coil and suspensions) is mechanically efficient and linear, requiring only modest powered amps to make it perform well. This driver is aimed strictly at the “audiophile” end of the market. Its cone is highly-resonance sensitive so clean low-distortion amplification and source components are advised.

For those listeners who value absolute detail, dynamics and clarity, the Alpair 12P is an excellent candidate. I’d like to thank all those who assisted in the design and development process, especially existing Markaudio driver users, who’s feedback was instrumental in the 12Pʼs final incarnation.

The recommended Max usable excursion = 5.4mm X 1 way (nonlinear bass load) and Max power handling = 30 Watts (Nom).

Running in: Carefully run the drivers at low volume using light music (NO artificial signal generation of any-kind) for the first 100 hours. After this period, gradually increase to normal listening volumes with the introduction of music that contains some bass. The driver will reach optimal performance at around 800 hours of play time.

Take great care not to touch the cones, or use any cleaning agents on their surface. Keep the drivers away from strong light as the UV may damage the coneʼs structure.

Full Parameters:

Revc	7.00 Ohm
F0	42.149 Hz
Sd	147.410 cm²
Vas	43.060 Ltr
CMS	1.369 m M/N
MMD	9.188 g
MMS	10.217 g
BL	7.540 T.M
QMS	1.981
QES	0.333
QTS	0.285
LeVc	53.952 uH
No	0.936 %
SPL0	91.730 dB

 

140mm Full Range drive unit 8 ohms single ferrite magnet

• Legendary full range drive unit
• 7in natural blue uncoated reinforced paper cone
• Operating range to 20KHz –very linear response
• Very low-profile multiform cone for broad directivity pattern
• Advanced low-distortion motor design
• Long-stroke hybrid mono-suspension with arrestor and progressive-rate spider
• Self-damping reinforced polymer basket