If you are on the lookout for a $25 Multimeter (or $15 on eBay) for working with low voltages, the best one right now in my opinion is the cute and tiny Aneng AN8008 TrueRMS Multimeter. It has a lot of functions and can measure µA current, and It’s a 9999-count meter. The continuity tester is reasonably fast, but there is one little problem that bothered me. It takes 5 to 10 seconds for it to settle on a correct voltage reading. When it finally ends, it’s spot on, but the waiting is annoying. But fortunately, there is a simple fix for this problem.
I’ve been modifying my Gigaworks Ebay DAC and think that the results is really showing. The second opamp is completely removed, the filter is changed to Cirrus Logics filter example from their prototype board and the first opamp is replaced with GD-Audio’s Earth discrete opamp. It sounds absolutely marvelous. Here’s the before and after graphs.
Here is the second part of how to improve the quality of an old CD player, the Pioneer PD S-505. You can find the first part here. In this section, I’m going to show you how to install a better, more stable clock circuit into your 505 to lower the jitter. This particular clock comes from Kingwa, that has a series of crystal oscillators for improving DVD players, CD players, and DACs. The price is reasonable. I’ve installed them in three different units and had zero problems, so the quality seems reasonable.
Ok, so why install a new clock? Isn’t there one in there already? Yes, your right. But by using better parts like crystals with lower ppm and also design a very clean power supply to feed the clock, you can make your CD-player sound much better. And the reason is lower jitter.
But what is jitter? There is plenty of excellent places to go read up on it. Here’s some. [Read more…]
Mods your Pioneer PD S-505 CD Player for better sound quality
So I bought this Pioneer PD S-505 for $40 to test how good audio quality I’m able to squeeze out by modifying it. But It will not be just the standard subjective judgment of improvement but also measurements. Back in 2000, you had to pay about $400 for it. It uses the stable platter which means you have to put the CD in upside down. So let’s get going.
There’s a lot of articles on the net about modding and enhancing the sound quality of your audio equipment by replacing components etc. But you never see measurements to backup their claims. Well, I’ve been busy the last two days taking a ten year old middle range CD player and trying to make it to sound really good. But I also have done measurements before and after doing the mod (within reason) and so far it actually confirms that modding really works (if done right). Now, let’s face it, the best measured equipment isn’t necessarily the one that sounds the best, but still, it’s interesting to see what kind of effects different modifications have.My best sounding DAC does not measure as well as some other ones I have. And I have started to get quite the collection.
Will be back with a writeup and test diagrams when I’m finished…