Koss ESP-9
Electrostatic Studio Monitor
Offers a new
tool for improved audiometry with self-bias or ac line energizing. Controlled
monitoring with 1 octaves ±2 dB range exceeding best loudspeaker systems. Eliminates all room reflections and polar
distribution problems.
Super
wide-range response - for critical,
controlled monitoring of finest recording sources. Delivers all 10 audible
octaves, 10 - 19,000 Hz (±5 dB), 4 octaves beyond ordinary headphones.
Virtually
distortion-free performance - precision
electrical balancing of push-pull acoustical circuitry to give fatigue-free
listening through long, intense recording sessions. Elements cancel all 2nd
harmonic distortion, unlike conventional units.
Lightweight
- human engineered for comfort - uses fluid-filled cushions for good,
comfortable seal; extendable stainless steel headband with wide cushion for
perfect fit and restful listening.
Calibrated,
precisely controlled output - ideal for audiometric uses - switch on front
panel of energizer selects ac operation for precision measurements of output;
in self-energized switch position no connection to ac lines is required; this
gives maximum convenience.
High-power
capability in very low bass range - lerge, oversize coupling transformers
mounted in external E-9 energizer unit give good wave form at 30 Hz with up to
10 volts input.
No special
amplifiers required - low efficiency, connects to low-impedance speaker
terminals - easy, quic hook-up to any rated high-quality amplifier delivers
performance to specification. Excellent for evaluating the spectral character
of very low level noise in equipment like tape mastering machines and recording
consoles. In contrast to the ESP-6 and ESP-7, both cups are independently
energized; al. Eft cup signal in not required to supply bias to the right cup.
E-9
Energizer: Contains 2 coupling
transformers, self-energizing circuitry, speaker/headphone transfer key-switch
and ac pilot light on black anodized front panel Also contains ac power
transformers, ac on-off switch, ac line fuse, and speaker terminals. Has 6'4" conductor input cable
terminated with 4 spade lugs to connect to amp. output terminals.
Size: 4 ½ H x 3 ¾ W x 6 ¼ D inches
Weight: 3 pounds
Specifications
Electrical
Frequency
Response Range, Typical: 15 -15,000 Hz
±2 dB (10 octaves) 10 - 19,000 Hz ±5 dB
Sensitivity: 80 dB SPL at 1 kHz ±1 dB reffered to 0,0002
dynes/cm² with 1 volt at the input
Total
Harmonic Distortion: less than 2% at 110
dB SPL
Isolation
from External Noise: 40 dB average
through fluid-filled cushions
Power
Handling Capability: Max. Continous
program material should not exceed 10 volts (12 watts) as read by an ac VTVM
(Ballantine meter 310B or equal) with average indicating circuitry and rms
calibrated scale, provides for transient peaks 14 dB beyond the continuous
level of 10 volts
Source
impedance: Designed to work from 4 to 16 Ω amplifier outputs
External
Power Requirements: None, except when
external ac line is selected on front panel switch of the E-9 Energizer (1/16
amp. 117 VAC, 50/60 Hz normally; 234 VAC with internal strap for foreign use)
Physical
Size
of Cup: 4 ¼" H x 3 ¾" W x 1
¼" D
Cushions: Fluid-filled for high ambient noise isolation
Headband: Extendable stainless steel bands with
self-adjusting pivoting yokes; conforms to any head size
Boom Mount
for Microphone: Knurled, anodized
aluminum knob on left cup with threaded shaft and 2 compressible rubber
washers; accepts all standard booms
Headset
Cable: Flexible, polyvininyl, 5
conductor shielded. 6" long, black with 5 prong plug keyrd to E-9
Energizer receptacle
Weight of
Headset Only: 19 ounces
Accessory
provided: 6" ac line-cord P.N
41-0235 for optional use