Comments on: Evolution of my home audio system http://schlachet.net/2011/04/evolution-of-my-home-audio-system/ Mon, 19 Mar 2012 19:31:47 +0000 hourly 1 http://wordpress.org/?v=3.3.2 By: stuarthttp://schlachet.net/2011/04/evolution-of-my-home-audio-system/comment-page-1/#comment-2287 stuart Wed, 13 Apr 2011 07:00:24 +0000 http://schlachet.net/?p=1495#comment-2287 Nice Jason! Looks pretty clean, I bet it sounds great. Nice Jason! Looks pretty clean, I bet it sounds great.

]]> By: John Brian Kirbyhttp://schlachet.net/2011/04/evolution-of-my-home-audio-system/comment-page-1/#comment-2286 John Brian Kirby Wed, 13 Apr 2011 06:45:50 +0000 http://schlachet.net/?p=1495#comment-2286 I'm probably not stating anything you don't already know, but for anyone else that happens upon your description: in addition to amplifying the minute voltages coming out of the cartridge, phono preamps also apply very specific equalization (RIAA EQ) to produce the expected line-level output. Because of the very physical nature of vinyl audio "storage," low-frequencies have a tendency to produce wavy grooves that can cause distortion of skipping, so the those frequencies are heavily reduced before the record is cut. The phono preamp inverts that process, boosting the low end in a (hopefully) transparent way to restore the original signal. Similarly, high-frequency content is boosted prior to cutting the master then reduced by the phono preamp in order to reduce hiss and surface noise in the final line-level signal. In other words, if you try listening to the output of a phono cartridge without a proper phono preamp, even if you're able to boost the signal enough to be heard, you'll end up with a harsh, tinny, terrible sound. The EQ trick is one thing we can actually thank the RIAA for! I’m probably not stating anything you don’t already know, but for anyone else that happens upon your description: in addition to amplifying the minute voltages coming out of the cartridge, phono preamps also apply very specific equalization (RIAA EQ) to produce the expected line-level output. Because of the very physical nature of vinyl audio “storage,” low-frequencies have a tendency to produce wavy grooves that can cause distortion of skipping, so the those frequencies are heavily reduced before the record is cut. The phono preamp inverts that process, boosting the low end in a (hopefully) transparent way to restore the original signal. Similarly, high-frequency content is boosted prior to cutting the master then reduced by the phono preamp in order to reduce hiss and surface noise in the final line-level signal.

In other words, if you try listening to the output of a phono cartridge without a proper phono preamp, even if you’re able to boost the signal enough to be heard, you’ll end up with a harsh, tinny, terrible sound. The EQ trick is one thing we can actually thank the RIAA for!

]]>