Sep 1st, 2011, 20:31 | 只看该作者 #30 |
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好,只是不理解英文缩写,但并没有曲解磨机,http://diyparadise.com/8x1543dac.html,太夸张并了多少芯片呀。
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Sep 1st, 2011, 21:42 | 只看该作者 #34 |
软件基本靠载 硬件基本靠拆
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[zt] from http://ieeexplore.ieee.org/xpl/freea...number=4980715 Abstract A low noise and low drift amplifier has been constructed using several monolithic operational amplifiers in parallel. It is shown that each amplifier may be connected by only three resistors. An input noise of 0.15 μV (p–p) in the band 0.1–10 Hz was obtained with six amplifiers, and the noise is expected to decrease as N-1/2 as the number of units is increased. from http://ieeexplore.ieee.org/Xplore/lo...hDecision=-203 Abstract The theoretical minimum noise measure of a multipath amplifier (an amplifier that has multiple parallel amplifiers) is achieved by using the optimum source impedance and optimum gain for each amplification path. This optimum source impedance and gain can be calculated by replacing each amplifier with its optimum source impedance. The resulting noise measure is the same as the minimum noise measure of the amplifiers used. The theory is demonstrated by applying it to distributed am plifiers. In an ideal distributed amplifier, the magnitude of the optimum gain of the amplification paths decreases and the phase delay increases the farther the stage is from the input, with the decrease in gain being faster for higher frequencies. The challenge in designing broadband low-noise distributed amplifiers is to achieve optimum gain matching over broad bandwidths. A numerical optimization procedure that separates source impedance and gain matching is proposed and demonstrated by optimizing a 0.5-2-GHz distributed amplifier. An average noise measure of 0.3 dB is achieved, which is only 0.1 dB higher than the minimum noise measure of the amplification stages used. This increase is due to transmission line loss and gain mismatch. 还有专利:http://www.patentgenius.com/patent/4300101.html |
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感谢 老广 此篇文章之用户: |
dalplex (Sep 1st, 2011) |
Sep 5th, 2011, 10:09 | 只看该作者 #36 | |
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引用:
既然你手里有比较好的播放器或DAC,建议一起拿来做下比较。我周二、三、四白天比较方便,我们可以安排一下。 |
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Sep 6th, 2011, 13:24 | 只看该作者 #38 |
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今天得到退款,“Full refund now given and we also refunded you the cost for returning the unit to us.” seller是个非常不错的人,本来是我们私下交易的,并不是在ebay上,所以他其实完全可以不必在意这比交易的feedback的。 DALPLEX, 如果你的功放和音箱还行,也可以我带DAC过去,这样也解决了将来搭配的疑虑。我的毕竟是AV功放和自制音箱,很多人有成见的。我随便的。 |
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Sep 6th, 2011, 14:05 | 只看该作者 #40 |
Senior Member
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------------------------------- You Cannot Be Serious! |
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共 2 位会员 感谢 hugoo 发表的文章: |
老广 (Sep 6th, 2011), silent_fish (Sep 6th, 2011) |