PURITY TM Fully Powered Hybrid Electrostatic Loudspeaker u s e r ’ s m a n u a l
Thank you—to you the MartinLogan owner, for loving what we do, and for making it possible for us to do what we love. Purity Tested to Comply with FCC Standards FOR HOME OR OFFICE USE Serial Numbers: _______________ / _______________ Record your serial numbers here for easy reference. You will need this information when filling out your warranty registration. Purity’s serial number is located near the bottom of the backplate and on the shipping container. Each individual unit has a unique serial number.
CONTENTS Contents . . . . . . . . . . . . . . . . . . . . . Installation in Brief. . . . . . . . . . . . . . Introduction . . . . . . . . . . . . . . . . . . . Connections & Controls . . . . . . . . . . AC Power Connection Status Light Line Level (RCA) Connection Speaker Level Connection . . . . . . . . . . . . . Bass Level Control Break-In Placement & Room Acoustics . . . . . . Listening Position The Wall Behind the Listener The Wall Behind the Speakers The Side Walls Experimentation Final Placement . . .
INSTALLATION IN BRIEF We know you are eager to hear your Purity speakers, so this section is provided to allow fast and easy set up. Once you have them operational, please take the time to read, in depth, the rest of the information in this manual. It will give you perspective on how to attain the greatest possible performance from this most exacting transducer.
INTRODUCTION Congratulations! You have invested in one of the world’s premier loudspeaker systems. Internally powered with a high-resolution digital amplifier, the Purity provides an unprecedented level of system connection flexibility. Equipped with a standard line-level input, the Purity is able to connect directly to devices such as digital music players, flat screen televisions or even computers.
CONNECTIONS & CONTROLS AC Power Connection Because your Purity speakers use an internal power supply to energize their electrostatic cells and to power the internal amplifiers, they must be connected to an AC power source. For this reason they are provided with the proper IEC standard power cords. These cords should be firmly inserted into the AC power receptacles on the rear connection panel of the speakers, then to any convenient AC wall outlet (see figure 2 & 3).
volume control). Usually this is a headphone or pre-amp output. However, as this varies from device to device we recommend referencing your device’s user manual. Please note: When making or breaking connections from devices that utilize the Line Level input a popping noise may occur. This is caused by grounding and static discharge interaction. It is normal and to be expected when using this method of connection.
PLACEMENT & ROOM ACOUSTICS Listening Position Your speakers should be placed approximately two to three feet from the front wall, the wall in front of the listening position, and about two feet from the side walls. Your sitting distance should be further than the distance between the speakers themselves. You are trying to attain the impression of good center imaging and stage width. There is no exact distance between speakers and listener, but there is a relationship.
Tilting the Speakers Backwards and Forwards As the diagrams show in the Dispersion Interactions section of this manual (page 12), the vertical dispersion is directional above and below the stator panel itself. In some instances, if you are sitting close to the floor, slight forward tilting of the speakers can enhance clarity and precision. Tilt can be adjusted by adjusting the MiniETC spikes (see page 11).
your speaker slightly forward into the room. What happened to the bass response? What happened to the imaging? If the imaging is more open and spacious and the bass response is tightened, that is a superior position. Move the speakers back six inches from the initial setup position and again listen to the imaging and bass response. There will be a position where you will have pinpoint imaging and good bass response. That position is the point of the optimal placement from the front wall.
back? You have near-field reflections. Stomp your foot. Can you hear a “boom”? You have standing waves or large panel resonances such as a poorly supported wall. Put your head in a small cavity area and talk loudly. Hear a booming? You’ve just experienced a cavity resonance. Rules of Thumb Hard vs. Soft Surfaces If the front or back wall of your listening room is soft, it might benefit you to have a hard or reflective wall in opposition. The ceiling and floor should follow the same basic guideline as well.
DISPERSION INTERACTIONS Three Major Types of Dispersion Your Purity’s launch a 30 degree horizontal dispersion pattern. This horizontal dispersion field gives a choice of good seats for the performance while minimizing interactions with side walls (see figure 12). Make sure both speakers stand exactly at the same vertical angle, otherwise the image can be skewed or poorly defined. The wave launch of both speakers is extremely accurate in both the time and spectral domain.
HOME THEATER It had long been the practice of stereo buffs to connect their television to a stereo system. The advantage was the use of the larger speakers and more powerful amplifier of the stereo system. Even though the sound was greatly improved, it was still mono and limited by the broadcast signal. In the late 1970’s and early 1980’s two new home movie formats became widely available to the public: VCR and laser disc. By 1985, both formats had developed into very high quality audio/video sources.
ELECTROSTATIC ADVANTAGES How can sound be reproduced by something that you are able to see through? Electrostatic energy makes this possible. Where the world of traditional loudspeaker technology deals with cones, domes, diaphragms and ribbons that are moved with magnetism, the world of electrostatic loudspeakers deals with charged electrons attracting and repelling each other. To fully understand the electrostatic concept, some background information will be helpful.
Full Range Operation Another significant advantage of MartinLogan’s exclusive transducer technology reveals itself when you look at examples of other loudspeaker products on the market today. The Purity uses no crossover networks above 450 Hz because they are not needed. The Purity consists of a single, seamless electrostatic membrane reproducing all frequencies above 450 Hz simultaneously.
CLS™ (Curvilinear Line Source) Since the beginning of audio, achieving smooth dispersion has been a problem for all designers. Large panel transducers present unique challenge because the larger the panel, the more directional the dispersion pattern becomes. Wide range electrostats have long been one of the most problematic transducers because they attain their full range capabilities via a large surface area.
ELECTROSTATIC In the late 1800’s, any loudspeaker was considered exotic. Today, most of us take the wonders of sound reproduction for granted. HISTORY After a short time, Rice and Kellogg had narrowed the field of “contestants” down to the cone and the electrostat. The outcome would dictate the way that future generations would refer to loudspeakers as being either “conventional” or “exotic”. It was 1880 before Thomas Edison had invented the first phonograph.
In 1947, Arthur Janszen, a young Naval engineer, took part in a research project for the Navy. The Navy was interested in developing a better instrument for testing microphone arrays. The test instrument needed an extremely accurate speaker, but Janszen found that the cone speakers of the period were too nonlinear in phase and amplitude response to meet his criteria.
FREQUENTLY ASKED QUESTIONS How do I clean my speakers? Use a dust free cloth or a soft brush to remove the dust from your speakers. We also recommend a specialty cloth (available at the Xtatic shop at www.martinlogan. com) that cleans your speakers better than anything else we have tried. For the wood surfaces it is acceptable to slightly dampen the cloth. Do not spray any kind of cleaning agent on or in close proximity to the electrostatic element.
Will excessive smoke or dust cause any problems with my electrostatic speakers? Exposure to excessive contaminants such as smoke or dust may potentially affect the performance of the electrostatic membrane, and may cause discoloration of the diaphragm membrane. When not in use for extended periods, you should unplug the speakers and cover them with the plastic bags in which the speakers were originally packed. It is a good idea to vacuum the electrostatic portion of each speaker three or four times a year.
TROUBLESHOOTING No Output • Check that all your system components are turned on. • Check your speaker wires and connections. • Check all interconnecting cables. • Try hooking up a different set of speakers. The lack of output could point to a problem with other equipment in your system (amp, pre-amp, processor, etc.) Weak or no Output from Electrostatic Panel, Loss of Highs • Check the power cord.
GENERAL INFORMATION Specifications* System Frequency Response: 41–23,000 Hz ± 3db Dispersion Horizontal: 30 Degrees Vertical: 28” (71 cm) Line Source Sensitivity 93 dB/2.83 volts/meter (binding posts) 95 dB/2.83 volts/meter (line level input) Impedance 4,000 Ohms (binding posts) 14,000 Ohms (line level input) Crossover Frequency 450 Hz Components Custom-wound audio transformer, air core coils, high-efficiency, high-resolution amplifier Bass Level Control +3dB, flat, –3dB Woofer Type Two 6.5” (16.
DIMENSIONAL DRAWINGS Dimensional Drawings 23
GLOSSARY OF AUDIO TERMS AC. Abbreviation for alternating current. DC. Abbreviation for direct current. Active crossover. Uses active devices (transistors, IC’s, tubes) and some form of power supply to operate. Diffraction. The breaking up of a sound wave caused by some type of mechanical interference such as a cabinet edge, grill frame or other similar object. Amplitude. The extreme range of a signal. Usually measured from the average to the extreme. Arc.
Inductance. The property of an electrical circuit by which a varying current in it produces a varying magnetic field that introduces voltages in the same circuit or in a nearby circuit. It is measured in henrys. Inductor. A device designed primarily to introduce inductance into an electrical circuit. Sometimes called a choke or coil. Linearity. The extent to which any signal handling process is accomplished without amplitude distortion. Midrange. The middle frequencies where the ear is the most sensitive.
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WARNING! Do not use your Purity loudspeakers outside of the country of original sale—voltage requirements vary by country. Improper voltage can cause damage that will be potentially expensive to repair. The Purity is shipped to authorized MartinLogan distributors with the correct power supply for use in the country of intended sale. A list of authorized distributors can be accessed at www.martinlogan.com or by emailing info@martinlogan.com. ® Lawrence, Kansas, USA tel 785.749.0133 fax 785.749.