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 HDMA. It sounds absolutely marvelous. Here’s the before and after graphs
This is the second part on how to improve the quality of an old CD player. 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. This particular clocks comes from Kingwa, that has a series of clocks 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 good.
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 player sound much better. And the reason is lower jitter.
But what is jitter? There is plenty of really good places to go read up on it. Here’s some.
http://www.audiocraftersguild.com/AandE/cd-jitter.pdf (PDF warning)
http://www.stereophile.com/reference/590jitter/
Ok, lets look at the schematic. Here you can see the clock and two capacitors, C404 and C403 and the clock is X401. The clock is feeding into the DAC (PD2029A) (you can find the complete schematic in part one)
We need to remove the crystal X401, and the two capacitors, C403 and C404. The old load capacitors are no longer needed. The next step is to connect the Kingwa clock to the DAC. As seen on the schematic, the clock is 16.9344Mhz, so we need to use the correct outlet from the Kingwa clock. There is three different divisions of the clock. You need to solder two connections. One for the ground, labeled GND, and the one just next to it, labeled 1/4F0.
Now we need to feed the signal generated from the new clock to the DAC. Connect one of them to the hole in C403 furthest away from the DAC. I put the GND line here. The other one should go where the old clock used to go. Use the one closest to the large capacitor for the DAC (see picture).
The Kingwa clock is going to need power. Any voltage between 10-30 V DC will do. I will have an upcoming article about the power supply I built for it. You will find the connectors for the power on the over side of the Kingwa clock.
Next step, testing. Put in a cd. If you have the cover removed when doing this REMEMBER DANGER HIGH VOLTAGE! No touchy touchy while doing this. Not on the part we soldered but on the power supply. Anyway, If you didn’t know this you really should not be doing this in the first place.
When you press power it should read the TOC from the CD. Press play. If the display shows the seconds ticking, you can turn the player off, unplugg and put the cover back on.
Lenn-Art Subwoofer
Last time I ordered some speaker elements from Germany I ordered some extra Tang Band W8-740C subwoofer elements for a later build. I’ve been oogling this design to go with my home-built?ProAc 2.5 clones. Micke, a friend will make the boxes for me, provided I sent him the drawings. What an exellent excuse to try to learn Solidworks. Amazing program. I have designed my own version of the venerable GainClone amplifier with a beefed up power supply and will use two subwoofers in stereo. Nice to not have to build the boxes. Last time when I built the clones the apartment was filled with MDF dust for months.
I’m going to do the last installations tomorrow. And finally start measuring my listening-room so I can create a DRC setup. I’ve done some experiments, and the sound improvement is amazing! So there’s going to be a lot of sweep sounds in my apartment tomorrow.
Part two of this series is now up. Read on how to install a better clock.
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 judgement 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.
The steps I planned is the following:
Ok, lets look at some stuff we need to do. First we have to remove the mute transistors. Less stuff in the audio path equals better sound. The transistors is just there to make the measurements look better for reviews. So they have to go.
Click for larger image
So transistors Q403, Q404, Q453 and Q454 is removed. Desolder och just clip the pins (carefully) with a wire cutter.
Next step, time to desolder the opamp which is a rather old opamp (NE5532). Desolder the opamp IC405 and solder in a socket for easy testing with different opamps. I settled on LM4562 at first.
Remove the heaphone opamp if you don’t going to use it. It’s better to buy an external headphone amplifier like V-CAN Tube Headphone Amplifier or better.
That’s about it for today. Next installment, upgrade the clock to improve jitter numbers…
On to part two on how to add a better clock to your PIONEER PD S-505
Well, let’s face it. The iPod have changed my interest in music during the last few years. With my 5 gig first generation iPod I had most of my music coded in 128kbit MP3 due to the constraints of the number of songs. The first year I put up with the included earphones and really didn’t think of upgrading.
But finally I got a Koss Porta Pro by recommendation from a friend. These headphones are not audiophile, but good enough to make me realize how much better MP3 files coded in 160 or higher sounded. But to accomondate that kind of upgrade in sound, forced me to buy a 15gb third generation iPod to fit more songs. So I recoded all my music to AAC in 160kbit and faced out older songs when I could get my hands on a higher quality version. The third generation iPod worked excellent for me for over three years. Then I upgraded my headphones to some in-ear headphones which took the sound quality up a notch again. A month ago I bought a iPod Classic 160gb and now have all music in lossless full quality.
But guess what, I bought a vinyl record player a while ago. Some would say that it’s a step backwards, but have to disagree. There is something about listening to vinyl. It’s like smoking a pipe, It’s a bit more involved. An other good aspect of this is that I’m forced to actually listen trough a whole song. But one thing is for sure, you need to invest in rather expensive equipment to get good performance from vinyl. But one can still find interesting records dirt cheap. It really is the black gold. 
I just bought a new Mac Mini Core Duo2 as a media player in my bedroom. I connected it an old 23″ Cinema display that I don’t use. First I was a bit annoyed that I needed to use the keyboard and mouse, but then I found Remote Buddy. What a relief! I can now do almost anything with Apples lovely simple remote. I’m going to use it for playing back my CD collection that’s been ripped to a large hardisk. Watching DiVX, DVD, MPG films on it. And watch TV with my EyeTV kit.
So the next step was getting the audio out of the mini. Well, let’s face it, the output quality from line-out isn’t something you can call great. So I’m about to order an Zhaolu DAC 2.5 and mod the crap out of it! I’m thinking of installing a ZapFilter, better clocking etc. I’m then going to use mini-spdif connector to get the digital data out from the mac to the DAC.
Now I just need to get my home built amp finished.
I want to have a couple of speakers in the beadroom, so I started to search the net. I found a very intresting DYI speaker project here (Swedish). So I ordered the speakers and can’t wait to get them. My skills in working with wood is very limited, but I may get some help from one of my friends, who is an expert wood carpenter.
The build is based on a German project called Lancetta (PDF warning) but with some modifications. Very cool using a small 3″ driver. I’ll try to post more info when I get started.