The 15-inch Celestion CF1540HD bass speaker is the smaller sibling of the well-established and
best-selling CF1840JD. Featuring a cast aluminum chassis, it reproduces frequencies from 35Hz
to 2,000Hz. With a power handling rated at 1,200W (AES standard) and 2,400W continuous,
the speaker is well-suited to the high output of the Class-D amplifier sections that see nearly
ubiquitous use today among P.A. and powered speaker manufacturers.
This impressive power rating is achieved first by using strategically sized and located airflow channels in the magnet assembly, producing a balanced airflow both within and around the voice coil and keeping the motor system cool. This counteracts power compression where a speaker’s output SPL is restricted as the voice coil increases in temperature—and therefore resistance—during peration.TheCF1540HD’s suspension and dust cap pump air as the driver cone moves, and its balanced airflow venting channels behave like a one-way valve. This ensures that air that has been heated in proximity to the motor assembly does not immediately return but is instead replaced by cooler air.
ALTI is proud to count these fine manufacturers to the ranks of our elite group of audio professionals.
The Elephant in the Room
by Barry Vogel: ALTI Executive Director
We needed another thing to stress over, right? The corona virus outbreak is raising a plethora of questions and concerns. I even questioned the wisdom of writing about it for fear of escalating the subject further. However, I believe that ignoring an issue is not resolving an issue. And I believe that common sense will prevail.
As of now, the virus has a 2% fatality rate. This is compared to a .1% fatality rate for the flu. The CDC has stated that the 2% figure is probably very inflated because most people who get the corona virus will not even know they have it! For most of us, it will seem like a cold or a bout with the flu. Between 30,000 and 60,000 people in America die from the flu yearly. Those most at risk are elderly or have underlying immune system issues. We do not sequester ourselves at home or don hazmat suits every year for flu season. Life will go on with corona virus as well. People will gather. Business will get done.
Common sense will prevail. Take precautions. Be aware. Here is your health and happiness checklist:
Eat healthy. A strong immune system is your best defense.
Get plenty of sleep. Shoot for 8 hours a night. (I know. Try anyway.)
Wash your hands often for at least 10 to 20 seconds.
Avoid touching your face as much as possible.
Hand sanitizer is not as good as washing hands, but better than nothing. Keep in mind that it takes at least 20 seconds for hand sanitizer to kill bacteria on your hands!
If you need to sneeze, do so into a tissue or a handkerchief. Do not sneeze into hands. Sneezing into your elbow is better than hands, but those germs can live for up to 48 hours there.
Hold off on the handshakes. (Tough one for me!) Go with a fist bump, elbow bump (as long as you didn’t sneeze there!), bow, or just a smile. People will understand.
It is no more dangerous to fly than to go to the grocery store. Really. Truth.
When possible, use knuckles, fist or elbow to push buttons and open doors.
Live your life. Do what you have to do.
ALTI-EXPO 2020 is on June 14 & 15 in Las Vegas. We and our members look forward to our annual event. Our program for AE2020 is unprecedented in its content and its mission. Our crossover with InfoComm will be another first. It will be learning on steroids. It will be opportunities everywhere. As many of our exhibitors and attendees already know, our smaller and less frenetic atmosphere is not only more productive; it is also healthier.
We look forward to welcoming you to ALTI-EXPO 2020. We’ll supply the hand sanitizer!
Resonado is looking for an Acoustic Engineer.
Resonado, Inc. is an early-stage, venture-backed technology company specializing in unique speaker transducer technology. As a multinational, fast-growing technology licensing company with offices in Palo Alto (CA), Chicago (IL), South Bend (IN), and Seoul (South Korea), we work closely with different businesses ranging from industry-leading OEM/ODM manufacturers to globally recognized brands whose audio products will utilize our patented speaker technology. Our technology can be applied to any speaker ranging from a microspeaker
used in the mobile devices to a large-size stadium speaker used in the football arena.
We, at our Chicago office, are looking for a motivated candidate in his/her early career with passion in audio who is ready for challenges by assuming a bigger role in a small, yet supportive organization. Our company maintains a horizontal organizational culture with a strong basis in meritocracy. With transparent communication and open channels welcoming new idea, our company is an ideal environment for a budding engineer looking to advance his/her career with new set of hard and soft skills, gain hands-on experience with industry leaders from both supply and product side, and become an early member of the fast-growing
company poised to bring a new wave of innovation to the audio industry.
Hear Adrian Weidman and Barry Vogel discuss the exciting Business Builders Workshop. Click here!
ALTI-EXPO 2020 Exhibitor and Attendee Registration NOW OPEN
ALTI-EXPO returns to South Point Hotel and Casino June 14 and 15, 2020 just prior to InfoComm 2020. Look for an expansion of our very popular Speaker Builders Workshop (SBW) that will also cross over to InfoComm for a first time ever event of its kind.
Please note the deadline dates and schedule. We look forward to placing your content front and center at ALTI-EXPO 2020
Early Commitment Exhibitor Discounts end SOON! Act now!
Design of Active Loudspeaker Systems with Typical Program Material
By Marian Liebig- Klippel GmbH
Lumped parameter modeling of the transducer and passive acoustical component is an effective starting point for building passive loudspeakers. However, digital signal processing (DSP) available in modern active loudspeaker systems creates new possibilities for the design of the passive components by actively equalizing the system to a desired target response. Thus, efficiency is one of the most important key design criteria for creating small speakers where power is saved in the pass band and used for an extensive bass boost at lower frequencies. This presentation, which is part of the Speaker Builder workshop, uses a new linear simulation tool (LSIM) to optimize the maximum output SPLmax for a given spectrum and crest factor of the audio signal (e.g. music) considering the maximum peak voltage and current capabilities of the amplifier.
Adaptive Nonlinear Control of the Transducer
By Peter Vanselow- Klippel GmbH
The transducer is not a linear component but limits the sound pressure output by nonlinearities and voice coil heating. A digital control algorithm based on loudspeaker modeling can compensate for undesired distortion and increases the maximum output without generating a mechanical or thermal overload of the system. This presentation, which is part of the DSP Builder Workshop, shows the practical application of the KLIPPEL CONTROLLED SOUND -technology (KCS) on a two-channel loudspeaker system developed in the Speaker Workshop. KCS is the first adaptive nonlinear control system integrated as an AUDIO WEAVER component in a cost effective DSP combined with a power amplifier driving the transducers. Adaptive control is realized by sensing the input current at the speaker terminals and compensating for production tolerances, climate, fatigue and load changes. KCS complements other DSP algorithms used for sound enhancement, echo cancellation, beam steering and further 3D sound effects.
THREE-DAY LECTURE BY WOLFGANG KLIPPEL
SOUND QUALITY OF AUDIO SYSTEMS - MODELING, MEASUREMENT & CONTROL
Klippel GmbH will present the annual three-day lecture about “Sound Quality of Audio Systems” held by Prof. Dr. Wolfgang Klippel on 9th-11th March 2020, at the Technical University of Dresden in Germany. The event is highly recommended for engineers of the audio industry active in research and development, manufacturing, quality control and also for students and teachers of the electro-acoustics.
IMPORTANT NOTICE: 2 Years ago, ALMA migrated to a new website and a new URL. Please discontinue using "almainternational.org". Our current website URL is https://almaint.org. Please discontinue sending emails to the old almainternational.org URL as well. Reach Barry Vogel at email@example.com. The "almainternational.org" URL has been shut down. EMails to almainternational.org will not be received! Please adjust your records.