Features
| Removable Grill | Yes |
|---|---|
| Warranty length | 5 Years |
| Brand | Martin Logan |
Tech Specs
- Frequency Response: 29–23,000 Hz ±3dB
- Recommended Amplifier Power: 20—550 watts per channel
- Horizontal Dispersion: 30°
- Vertical Dispersion: 44" (112cm) line source
- Sensitivity: 91 dB/2.83 volts/meter
- Impedance: 4 Ohms, 0.6 at 20kHz Compatible with 4, 6, or 8 Ohm rated amplifiers.
- Crossover Frequency: 300Hz
- High Frequency Transducer: XStat™ CLS™ electrostatic transducer » Panel Dimensions: 44" x 11" (112 x 28cm) » Radiating Area: 484 in² (3,136 cm² )
- Low Frequency Transducer: Two 8” (20.3 cm) cast basket, high excursion, rigid aluminium cone and extended throw drive assembly, non-resonance asymmetrical chamber format.
- Amplifier: Woofer: 2 x 275 watts/channel (4 ohms), 2 x 550 watts peak
- Room Correction (Bass Section): Anthem Room Correction (ARC™) ready (Sold Separately)
- Components: Custom-wound audio transformer, air core coils, polypropylene capacitors. 24-bit DSP based preamplifier (used with woofer amplifier).
- Audio Controls: Bass: ±10 dB under 75 Hz Mid-Bass: –2 dB, 0 db, +2 db ARC™ Room EQ: On, Off
- Signal Inputs: WBT-0703Cu nextgen™ 5-way binding posts feature a filigree signal conductor made from gold plated, nickel free, non- ferromagnetic, pure copper for high conductivity and fully insulated. Free from eddy current effects.
- Inputs: AC Power, RJ45 (for ARC), mini USB (for ARC)
- Power Draw: Idle: < 1W/channel Max: 500W/channel
- Weight: 90 lbs. (40.9 kg)
- Dimensions: 60.75" x 11.9" x 27.4 " (154.3cm x 30.2cm x 69.6cm)
Product Description
Martin Logan Classic ESL 11A active electrostatic speakers feature 11” Xstat panel transducers, as well as two 8” woofers powered by dual 275 Watt Class D amplifiers - in addition to 24-bit Vojtko designed DSP engine and ARC (Anthem Room Correction). The stator design features a MicroPerf design to provide almost twice the usual panel area. The curvilinear design also helps with high frequency dispersion.
MicroPerf stator design
The stator or grid is used to control the movement of the diaphragm, in an electrostatic speaker. Consequently, the ESL 11A uses MicroPerf technology, to provide almost twice the surface area of a traditional panel. The panel is reinforced with rigid ClearSpar spacers, making it almost visually transparent. They also tension the panel.
Airframe for larger surface area
The ESL 11A speakers use a custom designed Airframe Blade mounting. This is made of an aerospace grade aluminium alloy, that makes the panels extremely rigid. The bold curvilinear styling does not interfere with the panel's dipole sound. It also provides electrical and acoustical isolation. The result is less intermodulation distortion as well as vibration and resonance. The sound has remarkable low-level detail as well as accuracy.
Dual woofers for powerful bass
The ESL 11A features two 8” laser engineered woofers. They have aluminium cones and each sits in its own enclosed compact chamber. The woofer fires backwards, towards the wall, and uses PoweredForce bass alignment technology. This features smart phase-shifting to minimise the effect the wall has on the bass. The result is realistic bass effects with no booming.
Curvilinear line source technology (CLS)
The Curvilinear shape of the ESL 11A is more than just beautiful. It also performs an important function. The gentle curvature helps with high frequency dispersion, without compromising overall sound quality. The sound heard from a loudspeaker is a combination of the direct sound, and the sound bouncing off the walls and furniture. The reflected sound can muddy the sound stage and mask detail.
However, electrostatic panels are dipoles, in that the sound comes from the front and behind. This has the effect of cancelling out any sound going to the sides. The result is less reflection and a more accurate sound. Finally, the sound that goes to the rear also helps with ambience and detail.
Class D amplifier and crossover
The ESL 11A features powerful Class D amplifiers with an output of 275 watts each. Class D amplifiers are almost 90% efficient and generate much less heat than linear amplifiers. Moreover, midrange clarity is assured by the Vojtko designed crossover. This uses hand built air-core coils and the best polypropylene capacitors.
The precision tuned network preserves even microscopic sonic nuances. The crossover splits the audio signal into two bands. It is basically a high pass filter that sends only the mid and high frequency sounds to the panel with bass being sent to the Woofers. The ESL 11A also has an adjustable bass level, and a switch to select the mid/bass transition level.
ARC room correction
As we know, the layout of a room can greatly affect the sound of your speakers. Martin Logan have introduced Anthem’s ARC to an electrostatic loudspeaker. ARC stands for ‘Active Room Correction’, and uses a microphone to monitor the sound in the room. This is particularly important with bass frequencies as phase shifts caused by furniture and the like can make the bass sound unrealistic.
ARC compares the actual sound from the microphone with a set of stored curves and then corrects the sound to account for how the room affects the sound. Along with the PoweredForce bass technology this creates the best possible sound quality and ensures you hear the speakers how they should be heard.
Connectivity and digital signal processing
The ESL 11A features 5-way audiophile grade WBT binding posts. This pure copper connection is free from current effects. The posts are also insulated for shock protection and fully damped against vibration. Martin Logan uses a proprietary Digital signal processing system that is 24-bit. It can deliver detailed low frequency sound down to 24Hz. The advanced DSP has full control of the sound to give a full and original picture of the sound.
