Build a Playstation 1 CD Player

I’m a sucker for geeking around with hifi equipment. The time I have spent working as a sound engineer has left me over-analysing sound, and my home hifi grants me an opportunity to get involved with that obsession. You can imagine therefore how pleased I was when I started to read about the fuss being made of the old Playstation 1’s DAC chip.

A DAC is a system which takes digital audio (110010011001010) which is stored on mediums like CD’s and mp3’s and the like, and converts it into an analogue electrical signal. To try to explain the importance of the DAC, let me refer briefly extensively to a zoetrope. The zoetrope is one of those spinning drums with several pictures stuck to the inside separated by narrow slits. When the viewer looks through one of the slits, they can see the image stuck to the opposite side of the drum and when the drum is spun around and around, the still images meld into a moving image, a film. So with digital audio, the audio signal is cut up into still images, around 44,100 every second on a CD, up to 48,000 in an mp3 and up to 192,000 in other better quality digital files. In order to turn these still images back into a sound, which our ears can hear, a DAC will work in a similar way to a zoetrope. It is the slits in the drum, the motor that spins it and the lighting. Give it the speed at which the drum must spin, the size of the image and the size of the drum and it will spin up the motor, arrange the slits to be in the correct place and the correct size and before you know it you’re listening to the closest representation of what was stored in those digital snapshots as possible, coming right out your speakers and into your ears.

The DAC’s we all have in our computers, iPod’s, cheap CD players etc. are like zoetropes that were made in a hurry, on the cheap. They do the trick, A few slits rammed into an old oil drum and BANG, there’s a moving image. A high quality DAC is like a custom-designed, freshly-machined piece of carefully chose metal with no flex and nanometer perfect slit-slicing. They provide absolute detail, perfect lighting and clarity. The cost difference is similar to this analogy. And so, the hit of the whole article here is, that there is a fuss being made of the first generation of Playstation 1’s because the DAC chip used in these gaming consoles is a workhorse of high-quality design, and one worth more than the £5-£10 cost of the old console. There are some drawbacks of course. Firstly, not even all the original Playstation’s are suitable, it must be one of the first generations, without going into detail, identifiable by three RCA connections, red, yellow and white, built into the rear of the console, and secondly, there are some components soldered the the logic board which need to go.

This guide is really a layman’s summary of parts of the work documented on Mike Feuerbacher’s log of his extensive geeking out on the subject here.  I don’t want to repeat instructions which have already been asserted brilliantly, so this is a full guide to getting going, including reference to other sources. Here’s what I did…

You will need…
– One or two (in case you mess up the first one) Playstation 1’s with RCA connections on the back.
– Soldering equipment, including a meter to test your work at each step.
– 2x audio grade 3.3uF capacitors (I got mine from Maplin).
– 2x 22k resistors.
– Some jumper cable.
– Some precision cutting tools (I have a Dremel with some cutting wheels).

Step 1 – Make sure the Playstation works.
This is obvious. Don’t forget it though.

Step 2 – Tear it down. 
You will need to strip the Playstation down and remove the logic board, that’s the big green circuit board. You don’t need to remove the power supply. It would undoubtedly help audio quality if you were able to re-house the supply in a separate case, but I question whether the improvement would be significant enough to take the time out.

Use this guide on iFixit. iFixit is great. The Playstation in the pictures is subtly different to your Playstation, do not be discouraged, it’s one of those crappy second or third generation ones. DO NOT BREAK ANYTHING, take your time, some of those cables are delicate.

Step 3 – Disable the ‘door open’ switch.
Locate the switch which indicates to the Playstation system that the door of the CD drive is open. When you close the lid, a little piece of plastic pushes another piece of plastic which closes this switch. We want to be able to open the playstation lid without turning it off, so turn the logic board over, locate where the switch pins come through to the underside of the board, and solder a little jumper across them. The switch is now redundant.

Step 5 – Remove the horrible muting transistors.
Mick Feuerbacher’s guide is really good for this part. I’m not going to mess about repeating it with less quality and detail, thereby clogging the internet up with repeated crap. He is clearly a better geek than I. Essentially, you are disconnecting the collector of these transistors and removing them from the circuit. They are horrible. We don’t like them.

Step 6 – Remove the horrible DC blocking capcitors.
I feel terrible, but talk to Mick again here. What am I doing with my time off? What’s the point in this guide? Should I be doing something more constructive? It is important at all times during the process of modifying this Playstation that you do not pose any of these questions to anyone or anything.

Do not be forceful here. The connections on those capacitors are soldered to a metal pad fused to the circuit board underneath. I found if the solder is not properly melted and you apply force, lifting the capacitor, it will pull the pad away from the board. If you do that by accident, CHUCK THE WHOLE LOT IN THE BIN. You have been warned.

Just to keep you up to date, essentially what we’re doing here (in steps 5 and 6) is removing the components which are protecting audio noobs who play Playstation from having auditory problems with they’re equipment through a complex process of it being rubbish. In order to protect them, Sony has installed componentry which takes takes all the good work that DAC chip has done for the audio, and cuts it out so that it sounds a bit more average.

Step 7 – Replace the output section.
So don’t follow Mick directly here. He describes initially bypassing the capacitors we just removed with a couple of jumper cables. Move on, further down his webpage, this latter section is worth doing.

Now that we’ve cut out all those annoying protect-y components out in steps 5 and 6, we need to replace them with some awesome protect-y components for super-leet-CD-listeners like ourselves. The main problem with these components is that in order to be as leet and awesome as we are, apparently, they need to be massive. Note the location of the enormous capacitors in  Fig. x, we will be slicing pieces out of the case to fit these in seamlessly, without them bumping into the CD spinning nearby. They are arranged at the rear-right of the playstation, just out the way there. I’d recommend installing the resistors on the underside and jumper cables going through the circuit board, then fitting the logic board back into the bottom part of the case, so you can visualise accurately where the capacitors are going to sit.

Step 8 – Slice up the cowling and case to fit it all in.
Once you have got those capacitors in place and soldered, you can re-build the Playstation. BALLS! It doesn’t fit together anymore. I took my Dremel at this point carefully cut enough space in the aluminum cowling so that the caps poke through neatly. You must be careful to make sure you don’t completely destroy the stuctural integrity of the console (although it will probably not be as good as before) as well as ensuring that the earthing strap which was stuck onto that cowling, is still able to attach back to the cowling.

I also found that the recess in the upper part of the case which the CD lid closes into needed a little gentle slicing. And the hinge mount underneath as well. I adapted this with some trial and error here to make it all fit. There are some important structural fittings that need adapting, so be dead careful and don’t cut off more than you need to.

Step 9 – Test it.
The video in Fig. x shows me testing the Playstation without fully re-assembling it. Make sure everything you have done works. It also looks awesome without the case on and I may well leave mine like that, although you mustn’t really do that because the electrics will get all dusty and you may be at any moment blinded by the laser or electrocuted to death by something or other.

Step 10 – Re-assemble, relax.
That’s it, re-assemble the upper case, plug it into your stereo and sit down with a cup of something hot. You will need to plug in your controller, START is the play/pause button, SELECT is the stop button, L1/R1 are your track skipping buttons and L2/R2 are your search buttons. Without hooking it up to a screen you can find the controller becomes unresponsive because you’ve selected some other settings without meaning to, press the reset button on the Playstation in these situations.

Notes.
The internet agrees that the Playstation should never be turned off if required to sound at it’s best. You may use the reset button if you need to reset it. I don’t like this, energy consumption and fire hazards are a concern.

If you buy one of those little screens off eBay with a yellow RCA connection, you can play awesome PS1 games from charity shops. Geek out!

This thing sounding good relies as always on you having a sweet amp and a sweet set of speakers (sweet, not expensive necessarily). Your hifi is only as strong as it’s weakest link.

Here’s some pictures that might come in useful to you…

ps1_1
Fig.1 – The hole being cut in the cowling.
ps1_2
Fig.2 – Close-up of cabling on the top of the board.
ps1_3
Fig.3 – Close-up of the underside of the board with resistors.

 

And here’s a video that shows how awesome it is without a case on. Don’t look at the laser…

Playstation 1 CD Player from Si2 on Vimeo.