User manual ELECTRO-VOICE EVI-28 EDS

[. . . ] EVI-28 250-Watt Two-Way Compact Vari Intense® Speaker System · Ground-breaking advance in singlebox utility · New small-format Vari Intense® horn for consistant SPL throughout the room · DH2010A titanium compression driver · Dual 8-inch high-power woofers with amplitude, frequency and delay shading · 1400-watt peak, 250-watt long-term power capacity · Secure terminal strip inputs · Compact, lightweight, refinishable, easy-to-install enclosure with U-bracket option horn driven by the DH2010A one-inch throat, wide-bandwidth, titanium-diaphragm compression driver. This driver uses a unique, convex-drive Time PathTM phasing plug structure (U. S. The voice coil is coupled to the diaphragm with EV's exclusive Resonant DriveTM technology. This increases and smooths the high-frequency response and reduces the amount of internal equalization for flat frequency response past 25, 000 Hz. [. . . ] If the under-balcony seating area is only 35 feet deep, then the enclosure should be tilted down by about 10 degrees relative to the floor in order to prevent excess slap echo and preserve intelligibility. Figure 10 shows a typical small-room application, perfect for a 20-foot by 30-foot boardroom or meeting hall. In this case, the head height is actually defined by a standing height of approximately 6 feet, so the long-throw axis should be very close to vertical. Then the included 40 degree angle points directly towards the entire listening area, minimizing slap echo while retaining a full width, high intelligibility and even SPL throughout the listening area. Power Handling To our knowledge, Electro-Voice was the first U. S. manufacturer to develop and publish a power test closely related to real-life conditions. First, we use a random-noise input signal because it contains many frequencies simultaneously, just like real voice or instrument program. Second, our signal contains more energy at extremely high and low frequencies than typical actual program, adding an extra measure of reliability. Third, the test signal includes not only the overall "long-term average" or "continuous" level - which our ears interpret as loudness - but also short-duration peaks which are many times higher than the average, just like actual program. The long- 2 EVI-28 250-Watt T wo-Way Compact Vari Intense® Speaker System term average level stresses the speaker thermally (heat). The instantaneous peaks test mechanical reliability (cone and diaphragm excursion). The sine-wave test signals sometimes used have a much less demanding peak value relative to their average level, providing a much higher power handling specification than is appropriate for real-world use. In actual use, long-term average levels exist from several seconds on up, but we apply the long-term average for eight hours, adding another measure of reliability. Additional extremely highstress tests developed in-house push components to the limits to ensure long-term reliability under the most extreme cases of abuse. Specifically, the EVI-28 is designed to withstand the power test described in ANSI/ EIA RS-426-A 1980. The EIA test spectrum is applied for eight hours. To obtain the spectrum, the output of a white-noise generator (white noise is a particular type of random noise with equal energy per bandwidth in Hz) is fed to a shaping filter with 6-dB-per-octave slopes below 40 Hz and above 318 Hz. When measured with the usual constant-percentage bandwidth analyzer (one-third-octave), this shaping filter produces a spectrum whose 3-dBdown points are at 100 Hz and 1, 200 Hz with a 3-dB-per-octave slope above 1, 200 Hz. This shaped signal is sent to the power amplifier with the continuous power set at 250 watts into the 6. 9-ohm EIA equivalent impedance. Amplifier clipping sets instantaneous peaks at 6 dB above the continuous power, or 1000 watts peak. The EVI-28 has been thoroughly tested at an AES equivalent power level of 350 watts continuous for 2 hours with 1, 400 watt peaks. This procedure provides a rigorous test of both thermal and mechanical failure modes. [. . . ] Incidental and Consequential Damages Excluded: Product repair or replacement and return to the customer are the only remedies provided to the customer. ElectroVoice shall not be liable for any incidental or consequential damages including, without limitation, injury to persons or property or loss of use. Some states do not allow the exclusion or limitation of incidental or consequential damages so the above limitation or exclusion may not apply to you. Other Rights: This warranty gives you specific legal rights, and you may also have other rights which vary from state to state. [. . . ]