JamTech segmentation pulse length modulation digital amplifier
JamTech releases its technical characteristic performance test result of digital audio amplifier recently. The test result of the characteristic reveals, the technology of JamTech is in linear range and spectral noise level (spectral noise floor) Have gone beyond the impulse width of traditional simulation to regulate (PWM) on two indexes Class d amplifier and delta-sigma PWM digital amplifier. These two indexes are to use for weighing the important parameter of the fidelity intensity in digital voice systems. JamTech specially faces and consumes electronic product design and manufacturer that popularizes system interface of the audio frequency, its audio amplifier technology has already obtained the patent. This performance tests it is by industry's advisor Bascom H of audio frequency. King was carried out and proved. Such outstanding performance result mainly stems from JamTech extremely innovative segmentation (sub-ranging) PWM digital amplifier framework. This framework has avoided the distorted production mechanism of the traditional class d amplifier fundamentally. JamTech new digital amplifier can reproduce the slight voice signal superly faithfully, so can realize outstanding and remarkable audio frequency sharpness and plumpness, people review the early electronic tube analog amplifier (tube analog amplifier) Detail experience. In 0 to 108dBFS (Full Scale) Range in,it is equivalent to 18Bit, JamTech digital amplifier characteristic test result and bias of linear scales absolute in performance exceed 3dBs plus-minus, level. And by contrast, the typical range of traditional simulation PWM D amplifer A is 72-78dB (12-13) ,The range of delta-sigma PWM digital amplifier is 84-90dB (14-15) . The investigation of the linear subject brightness range is to pass the bias (DAL) which measures it and absolute linear scale Come to realize, it is the important index of weighing the fidelity intensity of the digital amplifier, can reveal that enlarge and think highly of the low-level tone now and mediate the order of accuarcy of sound effect in figure, and the two can give characteristics such as the abundance, detail and sharpness,etc. to voice signal. The standard CD tone quality audio frequency refers to 96dB or 16 resolution, this is considered to be lateral bottom margin of characteristic that audio frequency of high-fidelity can be accepted. In addition, if you want to fully represent the minor signal detail, must have spectral noise level low enough, in order to avoid cutting down the satisfactory voice signal. This performance tests spectral noise levels measured are - 150dBFS, this number value is even 7 times smaller than the minimum one can reproduce the voice signal. Traditional class d amplifier and spectral noise levels of the digital amplifiers are generally all between 100-105dBFS, this can not almost distinguish the low-level voice signal out from the noise signal. It is an item of one pair of horizontal figures that has already obtained the patent to be used in the segmentation PWM in the digital amplifier products of JamTech Company - -Impulse width transform technology, it can with higher than traditional single level, modulate precision of framework, drive the output stage. Segment (Sun-Ranging) This technology divides Entry into two signal components of magnitude, change separately, combine in the output stage again. The nonlinearity that the switch technology can avoid emerging because the brilliant chip technology of silicon analyzes in the time of impulse width the respect has limitation runs side by side in such direct data, thus has realized high-precision and high-fidelity result, therefore expand the available working range of the digital amplifier to 100dB, zero crossing is distorted (zero crossing distortion) at the same time Reducing with greater than multiple of 250 makes the digital amplifier characteristic improved too. The first products JM2020 of JamTech are orientated as the market of digital television, in the test stage at present. JM2020 peculiar integrated design reaches one grade of integration of controller and power on the single chip, equivalent to digital amplifier price of newer delta-sigma PWM with the traditional class d amplifier, but the fidelity characteristic is more outstanding. The future generation of JamTech segments PWM digital amplifier will be put into testing in the fourth quarter, this product will have the better fidelity characteristic and step voltage of output less than 20 watts. Because digital amplifier technology make limpid audio frequency experience, become possible like the crystal, performance of the dwarf signal becomes the key factor so it reappears. JamTech has already announced its technical performance test report of amplifier. This report regards DAL index as the important basis, through determining the output amplitude and corresponding input signal level while deviating from of inputting the amplitude, carry on the assessment to the digital amplifier products in the inner fidelity characteristic of the working range. As a test originally used in the high-performance audio frequency D/A switching system of the attribute, it will be used in the input signal amplitde with lower signal more amplitde than the input that standard - 60dBFS probe tone will be tested and investigated the problem that the apparatus exists mainly.
