Playstation as CD-player

[jives11]

You can see his email at the bottom of the home page at

http://www.methe-family.de/index.html

The valve amps look quite something !

[pozo1992]

Hi gents,

This is my first post on this forum. Since quite a time I have been dealing with the use of playstations as CD player. So far my findings are following:
There are substantial differences between the various versions of the PSX, i.e. SCPH1002, SCPH5502, SCPH7502. There are more (SCPH7002, 9002,…) but I did not examine and test them.
Types 1002 and 5502 are using DACs of type AK4309 from Asahi-Kasei (discontinued delta-sigma DAC), whereas 1002 has got an OPAMP following the DAC the 5502 don`t. 7502 is built completely different, the audio signal just comes out of one of these big chips (I assume a DSP) and is fed to an I/V converter.
So what PSX is sounding best? This question can not easily be answered because hooking up the PSX to a preamp is not that straightforward. The older version (SCPH1002) has got RCA jacks, the others do not. So you must find a way to connect your “good” cables to the PSX in order to allow comparable conditions for listening tests. Still my evaluation goes on but so far I would say that to my ears the 1002 version sounds best. It would be interesting to hear about the experiences of other members. For the future I am planning to improve the AF stage. I would like to replace the Opamp that is following the DAC (NJM2100) by an OPA2134. Has anyone done this before, any results?

Pozo1992

[leadbelly]

Originally posted by pozo1992
So what PSX is sounding best? This question can not easily be answered because hooking up the PSX to a preamp is not that straightforward. The older version (SCPH1002) has got RCA jacks, the others do not. So you must find a way to connect your “good” cables to the PSX in order to allow comparable conditions for listening tests.

I don't understand why this is a big issue, since every model other than the 1002 uses the same A/V connector and cable, so as long as you cobble together something, it at least can be used for all the other models.

[pozo1992]

The problem with the AV connector appears to me like following:

When looking at this conector it seems to me not very reliable in terms of quality of connection compared to the Cinch/RCA connection.
As you may have experienced too, a bad connection, like a relay contact or a screw or a spring on a loudspeaker terminal can spoil the sound completely. If I am not wrong even Mr. Pass mentioned that issue in one of his papers about loudspeaker interconnections.
So for that resason I would like to have a solid conection to the audio cables for sound comparisons.
Of course I have tried some kind of "adaptor" to get the whole thing going but my concerns remain....
So I would prefer to have a solution with cables soldered directly to the corresponding point on the pcb and then a pair of solid RCA connnectors at the cabinet of the PSX. A lot more work but maybe worth it.

[pozo1992]

To add more fuel to the discussion about the playstation`s sound I have investigated the clock generation on the mainboard:

The older types, i.e. SCPH 1002 and SCPH5502 have got a separate oscillator of 67.7376MHz in order to clock the RISC CPU CXD 8806 whereas this clock frequency will be halved before it is send to the CPU itself. This divider seem to be inside the chip.

The 53.20MHz clock for the graphic processor CXD 8561 is generated separately too.
To me it seems, that the clock for the CD is generated by dividing the 67Mhz by four in order to get 16.9344 MHz. Doing this is very favourable in terms of signal quality, i.e. accuracy and jitter.

Now what`s different in models SCPH7502…..
The main difference is that all the required clocks are generated from a single quartz frequency (17.7343MHz) by means of a clock synthesizer IC named CY 2081 from Cypress.
This chip supplies the clocks for the RICS CPU, the graphic CPU and the 4.43MHz for PAL operation.
Here the quartz frequency must be multiplied first before it is divided down to the required 16.9334 MHz which implies more jitter and other inaccuracies.

So far my recent findings. Please comment and tell me your experiences.

Pozo1992

[el`Ol]

I just bought an scph-1002 for a friend. The imaging is very stable and indicates a manufacturing quality that is more common in the 2000 Euro class. But compared to my NAD 514 the latter has still a lot more soul and I prefer it much over the playstation.

[el`Ol]

I found out that the playstation had a strange power supply, so I changed it and it is much better now. Almost on the level of the NAD.

[DJNUBZ]

How does the sound of a ps1 compare to the sound from an xbox?

[Nanook]

This thread has grabbed my attention. I have what I think is a PS1 '1001 available to me (not much of a gamer and kids are too old to have even been interested). So what to do first? A rebox would be good, as would a modded or upgraded power supply. What next? Shielding? dampeniing? What about new RCAs ? and I assume the blue tack on crystal tweak will work.

who'd a thunk it? Trying to put together an excellent small scale system .. on the cheap of course!

[Nanook]

well I did manage to get the old playstation for $16 USD..
it's a 1001, the first generation North American market console. Picked up a hip gear remote for $3 USD new (at Blockbuster).

Apparently this is the "one", in Europe it's called the 1002 and in Asia it's the 1000. (different voltages, etc.)

Separate on-board power supply, RCA outputs (+digital out). It sounds surprisingly good, much better than it should. I will be re-boxing it into an old car audio amp case and installing an IEE connector on the back of it. Have some copper shielding, and will install a blue LED, as well as a "slider" door for it. I can bust the plastic "RCA" board mounted sockets and solder directly to the pigtails that will be exposed

Apparently nothing else need be done, except perhaps an 5" LCD screen (found one for $20USD) so I can see what I'm doing. The only other thing to do would be to build a near unity gain buffer to increase current and voltage out (although through my McCormack micro line drive in passive mode, there seems to be plenty of gain available). The fellow located here:

http://www.methe-family.de/index.html

emailed me and has encouraged me . I'll post my findings back here when I get to it and get it completed.