Neotera Audio Introduces Ultra Flat Series Woofers

Neotera Audio, which has manufacturing in Italy and engineering in Sweden, has recently released two rather interesting thin-profile 10" woofers, the UF295CBS, and the UF295FAS. Both woofers have a voice coil and motor structure located around the rim of the cone assembly, and both use and front and rear facing NBR surrounds for compliance. The UF295CBS was designed for small closed box subwoofer applications, while the UF295FAS is a a pure dipole woofer with a Fiberglass/Rohacell dome suspended directly on the voice coil.
 
This concept is somewhat similar to the Prescient Audio TD-12 subwoofer (characterized in Voice Coil, August 2015) in that the cone was also driven at its perimeter. This also makes the UF295FAS's 283.4mm diameter voice coil one of the largest diameter voice coils in the loudspeaker industry. This driver was characterized in Test Bench, Voice Coil November 2023.

The Neotera US295CBS has 2.6" depth from the top of the mounting flange to the top of the rear surround. This model has an aluminum cone and is intended for small, sealed enclosures. The UF295CBS device also requires some active filter or DSP manipulation.

Headquartered in Sweden, Neotera was founded in 2019 by a diverse group of loudspeaker/electronic design veterans focused on exploring these thin-profile designs. As the company explains: "To design a simple elegant solution, one sometimes have to solve very complex problems. Our chassis had to comply with many aspects and there was only one supplier on the planet willing to take on the challenge. Bruschi S.P.A. in Milan, Italy. Their open mindedness to extend the boundaries with us to create the high precision rings needed for the Ultra Flat Series  transducers resulted in the IZA award in June 2023.
 
"An international group of like-minded individuals launched Neotera in 2019 to present a complete set of new technologies to the global audio industry intended to challenge the conventional thinking and deliver new and unique outcomes for both manufacturers and end users. These new technologies cover performance enhancing transducers, electronics software and audio systems designs which can be tailored to suit each application. The initial products have been launched in 2023 with an extensive roll out plan to be initiated in 2024 targeted at both the professional and consumer audio industry."

Founding partners for Neotera include Erik Thorsell, Greg Turnidge, and Maurizio Servadio. Thorsell invented and patented the popular "Fresh Air" car subwoofer system and is based in Sweden. Turnidge is the Managing Director of Neotera and Blue Acoustics (Blueacs) and is based in Australia. Servadio is the engineer who invented the Neotera Ultraflat technology and is based in Italy where the UF295FAS is manufactured. 

Interestingly, both Thorsell and Turnidge worked with Neville Thiele for years up to his passing, which is impressive. In addition, industry veteran David Stephens is Director of Sales & Marketing for Neotera. Voice Coil has explicated several thin-profile woofers over the years, including drivers from Dayton Audio, Prescient Audio, SB Acoustics, and Wavecor. Virtually all of these previously featured woofers were subwoofers with the thin-profile aspect meant to complement shallow depth mounting situations.
  While being a thin-profile woofer with a depth of 2.6" with a low-frequency response down to 29Hz, unlike the other thin-profile woofers, the Neotera UF295FAS (pictured above) has a upper frequency response that allows it to be crossed over as high as 1kHz. However, what really distinguishes the UF295FAS is that it is specifically designed for dipole system applications in the vein of a speaker, such as Sigfried Linkwitz' LX521 constant directivity dipole speaker.
  Of these two variants, the US295CBS (pictured above) has 2.6” depth from the top of the mounting flange to the top of the rear surround. This model has an aluminum cone and is intended for small, sealed enclosures. The UF295CBS device also requires some active filter or DSP manipulation. Thiele-Small (T-S) parameters for the UF295CBS are: Re = 3.9Ω; Fs = 19.5Hz; Sd = 394cm2; Mmd = 460gms; Qms = 4.4; Qes = 2.1; Qts = 1.4; and Vas = 30 liters. The Klippel LSI Bl(x) curve is shown in Figure 1, with the Kms curve depicted in Figure 2. Obviously, the compliance is well controlled, something not always seen with thin-profile woofers.

The second model, the UF295FAS has 2.2” depth from the top of the mounting flange to the top of the rear surround. This model has a glass fiber cone and is intended for dipole applications. T-S parameters for the UF295FAS are: Re = 7.34Ω; Fs = 30.4Hz; Sd = 437cm2; Mmd = 92.2gms; Qms = 4.6; Qes = 1.7; Qts = 1.25; Vas = 72.3 liters. The Klippel LSI Bl(x) curve was not available on this model, but the Kms curve is shown in Figure 3. Like the UF295CBS, the compliance appears to be well controlled.
www.neoteraaudio.com