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Frequently Asked Questions

  • Where are B&C components manufactured?

    Like a high end sports car, B&C components are on the leading edge of professional audio, pushing thresholds in order to maximize performance. While B&C uses the best available parts from around the world, all of our components are designed, assembled and tested at our factory just outside Florence, Italy. We feel this is critical to ensure the long-term reliability of our products.

  • What is the warranty on B&C components?

    The warranty on B&C components remains in effect for three (3) years from the date of the first consumer purchase. The original owner and all subsequent owners are protected as long as the components have been purchased from an authorized B&C distributor or retailer. The original, dated bill of sale is required whenever warranty service is required. Please have this available before contacting your B&C retailer or distributor.

  • The B&C woofer or high frequency driver in my speaker cabinet is not working. Who should I contact?

    B&C does not repair components. You should contact the retailer that sold you the speaker cabinets, or the manufacturer of the speaker cabinets directly. If you made speaker cabinets yourself using B&C components, you should contact the retailer or B&C distributor that sold you the components.

    While some manufacturers use standard B&C components, many use customized versions of our components that satisfy their specific design criteria. Care should be taken to ensure that the correct replacement component is being used.

  • Is it possible for me to fix my own B&C components?

    B&C offers instructions on how to fix components in the resource section of our web site. Some high frequency drivers are quite easy to repair, but woofers can be a bit more challenging. We strongly recommend that you seek professional support for these procedures in order to ensure long term component performance. Using the correct repair process and adhesives is critical.

  • Where can I find parts to repair B&C components?

    B&C does not sell parts directly to the general public. You should contact the manufacturer of the speaker cabinets, or the retailer that sold you the cabinets or components. If they are not able to help you, you can contact your local B&C distributor. Please note that some proprietary components are only available through the manufacturer of the speaker cabinets.

  • Which speaker cabinet manufacturers does B&C make products for?

    B&C is a partner to many of the most famous OEM builders worldwide, however we are not at liberty to disclose a list.

  • Does B&C adhere to any international quality standards?

    Yes. B&C is a registered and up-to-date ISO9001:2008 manufacturer.

  • Does B&C offer design assistance for speaker cabinets?

    Sorry, but we do not offer design support beyond the simple speaker cabinet designs that available in the “Resources” section of our web site.

  • How does B&C test products before shipment?

    Every product from B&C Speakers is 100% quality tested before it is packaged and shipped. Each product is guaranteed and supported with a 3 year warranty. All components are electronically tested for rub and buzz issues. We also perform a set of measurements on every component to ensure that their frequency response and electrical impedance fall within established tolerance windows. Each cone loudspeaker is additionally tested using a low frequency, high-voltage acoustical sweep to check for vibrations or noises (rub and buzz).  

    B&C Speakers reserves the right to change specifications of the products without notice.

  • How does B&C calculate their power ratings?

    B&C’s specified Nominal Power Handling is measured according to AES2-1984 standard. The transducer under test is driven for a two hour period with pink noise signal, having a crest factor of 2 (or 6 dB) and filtered to the working range of the transducer itself (for instance, a 50-500 Hz range is typical for woofer testing).

    Cone loudspeakers are tested in free air. Compression drivers are coupled to their recommended horn. Power is calculated using the RMS value of applied voltage – averaged over the test period – and the minimum value of electrical impedance within the working range of the loudspeaker. After the test, the transducer must be in working order, without permanent impact on its technical performance. Due to the transient character of most musical programs, whose crest factor is commonly above 8 - 10 dB, it is customary to specify a “Continuous Program Power Handling”, double of the Nominal Power Handling, as a recommended amplifier power in order to fully exploit the thermal and mechanical capabilities of the transducer without any clipping in the amplifier stage. On the contrary, when the amplifier is pushed to its limits and shows frequent saturation, its power specification should be less than the rated Nominal Power Handling of the loudspeaker.

  • How does B&C calculate the Xmax (excursion) specification, and what is Xvar?

    Evolution is a process that affects not only products, but also their technical specifications. Constant advances in research provide more and more precise methods to measure the performance of loudspeakers, and describe their features. Thiele – Small parameters have become the universal language for describing loudspeaker behavior in the small signal domain. Nevertheless, they comment little on the working limits of loudspeakers in the large signal regime.

    These limits are customarily indicated by Xmax, the maximum linear excursion. This value is typically measured according to the AES2-1984 standard, corresponding to a maximum of 10% total harmonic distortion (THD) with a sinusoidal signal (though most manufacturers, including B&C, now typically provide data for Linear Mathematical Xmax, not measured Xmax). Recent research shows that this method can yield ambiguous results, and even different numerical values for the same loudspeaker. The main limit of this measurement is that it looks at the output signal instead of the physical features of the driver itself. On the contrary, the most up-to-date instruments for distortion analysis can measure the variations in loudspeaker parameters when they are fed with high-level signals. In this way, an excursion limit can be fixed, beyond which the parameter’s variation becomes excessive.

    The “X var” value reported in our data (generally after the traditional “Xmax” value) is measured this way. Beyond this excursion limit, the magnetic field seen by the voice coil, or the total suspension compliance, or both, drops to less than 50% of their small signal value, producing high distortion levels, strong variations from small signal behavior and power compression. The new technique yields different results from the standard measurement based on THD. B&C Speakers believes that this added information gives a more accurate and reliable description on loudspeakers behavior in actual operating conditions.

  • What is the EBP value?

    The LF driver's Efficiency Bandwidth Product (EBP) represents the tradeoff between the useful frequency range reproduced and the passband efficiency allowed by the driver in a horn loading system. The unit is Hertz.
    Maximizing the system efficiency causes a restriction of the frequency response, on the contrary a wide bandwidth is only possible with reduced efficiency. The bandwidth/efficiency tradeoff is controlled by choosing an appropriate throat size of the horn.

    It's clear that a woofer with a larger EBP value can yield a wider bandwidth or an higher efficiency in the horn system than a woofer with a smaller EBP. Also, EBP dictates the maximum available efficiency; it's not possible to design a horn system more efficient than the driver permits.

    The EBP value is also useful to understand the LF performance of a woofer in direct-radiator enclosures (closed or vented). In order to obtain a flat alignment with an f(-3dB) around 40 Hz in a closed box, a woofer EBP around 50 Hz is enough; using a woofer with a larger EBP value will result in a higher f(-3dB). For a vented box, an EBP of no more than 100 is required in order to get the same LF cutoff.

    It can be concluded that, while a horn loading system requires EBP values as large as possible to maximise efficiency or bandwidth, especially in mid-bass and midrange horns, direct radiator enclosures require much lower EBP values, if a flat and extended LF response is the design goal.

    However, successful bass horn systems have been designed using woofers with EBP around 120-150 Hz. Although this value is only slightly larger than the one recommended for a bass-reflex cabinet, the restricted bandwidth required allows a good system efficiency.

  • What is the issue with DC Offset?

    A known issue of the dynamic loudspeaker is the instability of the average working position for frequencies above the resonance frequency. In this range, because of the phase relationship between force and position, the variations of force factor Bl vs position drive the moving assembly away from the Bl maximum. Intuitively, the loudspeaker tends to “slide” down the slopes of the Bl(x) curve. This is referred to as DC offset.

    Since the rest position is the optimal average working point, DC offset leads to several bad consequences: reduced excursion capabilities, increased mechanical stress, and increased distortion.

    This is  due to the loudspeaker working in a region where nonlinearities are larger, and thermal dissipation and power handling are lower. Generally speaking, a large amount of DC offset leads to poor performance and shortened loudspeaker life.

    All B&C loudspeakers are designed with DC offset reduction in mind, especially long throw subwoofers. Our motors are designed to have a large plateau around the rest position, both through magnet assembly optimization and voice coil design. Reducing the slope of the Bl curve, especially in the central region, will reduce instability and therefore the amount of DC offset. A special winding technique has been adopted in the most critical cases. Our suspensions are also designed to counteract DC offset before it degrades performance.

  • Does B&C provide MSDS (Materials Safety Data Sheets), RoHS and/or REACH documents for their products?
    An MSDS is not required for electroacoustic transducers (cone loudspeakers or compression drivers) because they are not considered dangerous or harmful for your health as finished products. All B&C products meet the RoHS and REACH compliance regulations. Please check the documents below for more information.

  • What can I do if I think that my B&C product is of questionable origin?
    Please check our resource pages for more information.