Philips CD-104 servicing tips on my own modified NOS unit.

[@giovanniiovino168]

Bellissimo video, io sono un felice possessore di un 104 comprato usato per pochi euro, cambiato alcuni condensatori e le ampolle del relè, suona una meraviglia, senza modifiche..... figuriamoci se faccio upgrade.... comunque complimenti salverò questo video!!!

[@waheex]

Great video. My Cd104 I have to gently knock it on the top cover to get it to read a disk. The griplets have been resoldered so suspect the many flying cables

[@delatronics3257]

Thanks! Yes the cables often break at the connector but it is possible to rewire with new suitable cable. Do double check that all the griplets have been sorted on both the servo and Decoder/DAC boards.

[@LilaKuhJunge]

The idea of oversampling is to do some of the anti-alias filtering in the digital domain and make the analog reconstruction filter simpler to increase overall sound quality. The problem CD has is that the maximum recorded frequency is around 20kHz and the alias artefacts will appear above 22KHz (44.1kHz being the sampling frequency and Nyquist around the corner). So your analog filter must drop 96dB in 1/10 octave which is almost impossible. 4x oversampling as in the 14bit TDA1540 moves the sampling frequency to 196kHz and computes the "missing values" via a digital reconstruction filter, so now the analog filter has 3 octaves to drop 84dB (5th order or less) - and a lot of reconstruction filtering was done in the digital domain already. This filtering is really important to get a valid reconstruction of the signal. If you don't filter, you get the inverted musical spectrum mirrored into your original audio spectrum via aliasing. This may have more "treble", but that will be mirror frequencies.

[@delatronics3257]

I know what you're saying but I can't hear frequencies above 15KHz never mind 22KHz, you should try NOS (it can be easily reversed), the results will astound you! I have been in professional audio electronics for over 35 years now; and in my opinion and many others, the TDA1540 DAC put into NOS sounds spectacular!

[@nicedaymovie941]

Grear video. I own one like this but original. Could you make a compaire Video between the 104 original and the Marantz CD-54 CD / Cd-73 ? I like the Look of the marantz a lot. Cheerleader Hans

[@delatronics3257]

Unfortunately now living in Brazil they are not available to buy here. The CD54 sounds the best unmodified as standard, the CD104 the best modified.

[@davidlowe1088]

@@delatronics3257Thanks for the video and your coaxial cable from the CDM - just what I needed. Why is the Marantz CD-54 best unmodified - no NOS?

[@delatronics3257]

@@davidlowe1088 I have been in audio electronics professionally since 1988 and have a musical ear; I am trained to hear harmonic distortion and noise and am a musician. I have serviced and owned many 1st and 2nd generation Philips players and most sound muffled unmodified; the CD54 does not and also the CD204 is not bad. The Marantz CD74 and 84 sound a bit thin and not so warm and rich IMHO.

[@davidlowe1088]

@@delatronics3257 Thanks. I have a 74 and the Magnavox FD3040, which is a variation of the CD84, and it is my favorite with NOS but sounds muffled without. I did replace the analog output wires, and that made a big difference. I just wondered what made the CD54 so good. I’ll keep an eye out for one.

[@marcse7en]

The pickup mechanism is called a "Swing Arm Pickup."

[@FrancescoPuglisiCorallo]

Piaciuto moltissimo Guanto si guasto lo portato per farlo riparare, ma non ce l'anno fatto difetto che non partiva.

[@marie-lisechiron9942]

Hello Delatronics. Thank you for your precious video. My CD 104 has a recent problem : no sound on the right channel (looks like a short circuit on the multimeter) . Any idea / priority of where to start?

[@delatronics3257]

@@marie-lisechiron9942 try swapping over the two output relays (one of them is no longer used)

[@marie-lisechiron9942]

That's so nice of you to answer that quickly... But I'm a bit confused not to fully understand what to do 😢

[@jeandeff65]

@@delatronics3257 Hello, where do you locate these output relays please Sir Delatro ?

[@delatronics3257]

@@jeandeff65On the Decoder board (white body, black bobbin they both look identical).

[@dfddwm]

Can you show the belt/gear assembly to aid replacement for beginners! David

[@delatronics3257]

Sorry, I no longer service these and I am in Brazil now where such units don't exist. I have my own which I shipped over with me but am not able to access it at present. It is very easy to replace the tray mechanism belt; 1. Remove top cover 2. Remove front panel 3. Remove drive (4 torx screws in each corner) 5 Remove tray loading assembly with 3 torx screws. It would take me 10 minutes.

[@dfddwm]

Hi, do you have any videos of repairing or fixing a sticking tray problem on a 104? My unit is recapped and sounds great (don't know whether any work was done on the DAC board!) but the problem is tray often doesn't work . Whether this is a mechanical problem or a failing component in the electrical system I can't tell. The motor is quite strong when it decides to work! Cheers David PS did you work at CES in Purley Way for Philips service?

[@delatronics3257]

No more videos to come on this, I am now living in Brazil and I only have my one. The problem is mostly caused by a slack belt or broken teeth on the tray gear com. Both items should still be available on ebay. No I didn't work for Philips, I am an ex Roland senior engineer who loves 2nd Gen Philips.

[@misterbool7349]

I tried NOS on my Marantz CD73 and I have to say that I've found the sound less dynamic and flatter. It's a question of taste.

[@delatronics3257]

The CD73 was an exception, I had to change the output capacitance and OP amp as well (don't ask me what to because it was 3 years ago and I can't remember).

[@FrancescoPuglisiCorallo]

Guesto cd 104 pilips lo comprato parecchi anni fa. Per un guasto, Che non partiva il mio techinico me la fatto buttare. Perche il lettore era guasto. Attento una risposta. Grazzie.

[@delatronics3257]

Tornerò nel Regno Unito a luglio di quest'anno e potrò ripristinarlo per te. Con il coperchio superiore rimosso dovresti essere in grado di vedere il laser illuminarsi (un piccolo punto rosso) senza un CD nel vassoio, il gruppo laser dovrebbe muoversi su e giù cercando di mettere a fuoco il CD. Se non si dispone del laser, potrebbe trattarsi di un guasto all'alimentatore o di un diodo laser bruciato (è necessario sostituire l'intero gruppo CDM1).

[@nicedaymovie941]

I have one too. Unfortunately he has Problem since a few days. When I turn it on, the 2 lights on the display don't light up and the drawer or start buttom doesn't work. Only when I press the Stop/CM button, the two lights light up and everything works as it should. The CDs are playing without any problems etc. Do you have a tip for me how I can fix this small defect? I just tryed it again, after switching on, 8888888 apeart. Another time just one line and the next time no lights. When i press Stop/cm, then the 2 stroke lights come up. Everything then works normal. On problems when playing... Greetings Hans

[@delatronics3257]

Possibly a bad plate through on a board (gripplet) or bad connector wiring.

[@misterbool7349]

Do you get the same improvment in sound quality by converting a SAA7220 to NOS ? I'd like to convert to NOS my Philips CD 160 but I don't know if it's worth it ? If you have other tips for improving the sound quality of that model, I'd love to hear them :)

[@delatronics3257]

Yes, I have done NOS conversions to TDA1540 and TDA1541 based systems and its always a huge improvement, it is like lifting a blanket off from the speakers!

[@mrgoodsound]

I have a CD304 when I put a CD in it doesn't spin up at all. I checked the voltages on the 5 regulator ICs against the schematic and they were all reading correct. Any ideas?

[@delatronics3257]

See if the lazer lense is moving in an out; it may be that it can't focus enough to spin up. Adjust the turntable height if you have movement of the lazer. If the lazer has no movement, you have a dead supply rail.

[@mrgoodsound]

@@delatronics3257 Thank you

[@tombill2723]

what about the Lampizator version of NOS ? Have you used the same mods.Cheers

[@delatronics3257]

Any NOS mod will make a huge difference, as the oversampling used by the digital filter sounds like throwing a blanket over the speakers; once modified, the soundstage increases vastly. My mod eliminates the OS and also cleans up all the data going to the DACs giving a much crisper data waveform with clock pulses sharper and in better alignment.

[@tombill2723]

thank you for the reply,the mods apply for the cd 304 aswell or best used unmodified?

[@tombill2723]

did you have both cd 304 and 304 mk2? any differences