Hello good folks,
I just got a Philips CD618 for 10bucks. Seems like a good deal so i bought it.
I don't know anything about this machine so therfore I need your help.
Is this a good transport? It is working, but the laser is really dirty, it will need a good clean and a "lube-up".
Does anyone have any experience with this machine, some modifications maybe or is it the usal: Better caps, better diodes and so on...
And also, does anyone have the servicemanual? I'm really curious abut
the laser in this machine.
Best regards,
Magnus Kofoed
I just got a Philips CD618 for 10bucks. Seems like a good deal so i bought it.
I don't know anything about this machine so therfore I need your help.
Is this a good transport? It is working, but the laser is really dirty, it will need a good clean and a "lube-up".
Does anyone have any experience with this machine, some modifications maybe or is it the usal: Better caps, better diodes and so on...
And also, does anyone have the servicemanual? I'm really curious abut
the laser in this machine.
Best regards,
Magnus Kofoed
Hi,
Just a little update of what I have done on my own, in case anyone else has the same player. I haven't found anything on this cdp on the forum.
First, it turned out it had a little problem. It was simply just acting wierd. The fault was ripple on the supply line to the microprocessor. Second the laser needed a good clean. It was smokecoloured from nicotine. Nicotine is a really sticky thing. I only did what was nessecery to get it function right 'cause I want to hear it "stock" before I get busy.
It was first tested against a denon cdp with standard modifications and from there it goes to a external DAC based on TDA1541A in NOS mode. The orignal analog output on the denon is not working anymore.
Here was the results:
Denon with external dac:
It sounded very soft, maybe a little to unfocusd, I preferd it over the
Philips.
The CD618 with analog output:
Very straight forward and a litte harsh and "digital".
The CD618 with the digital out to the DAC with TDA1541.
This suprised me a bit. It was soft, pleasnt, but much more focused.
It was a step-up from the denon.
So either my denon cdp is crap or the CD618 has great potensial.
If anyone has the servicemanual i would really have apriciate it.
Any input?
Best regards,
Magnus
Just a little update of what I have done on my own, in case anyone else has the same player. I haven't found anything on this cdp on the forum.
First, it turned out it had a little problem. It was simply just acting wierd. The fault was ripple on the supply line to the microprocessor. Second the laser needed a good clean. It was smokecoloured from nicotine. Nicotine is a really sticky thing. I only did what was nessecery to get it function right 'cause I want to hear it "stock" before I get busy.
It was first tested against a denon cdp with standard modifications and from there it goes to a external DAC based on TDA1541A in NOS mode. The orignal analog output on the denon is not working anymore.
Here was the results:
Denon with external dac:
It sounded very soft, maybe a little to unfocusd, I preferd it over the
Philips.
The CD618 with analog output:
Very straight forward and a litte harsh and "digital".
The CD618 with the digital out to the DAC with TDA1541.
This suprised me a bit. It was soft, pleasnt, but much more focused.
It was a step-up from the denon.
So either my denon cdp is crap or the CD618 has great potensial.
If anyone has the servicemanual i would really have apriciate it.
Any input?
Best regards,
Magnus
Hi Magnus
You won't find a lot of info on the CD618.....but fortunately for you...it is almost identical to the CD624. They share the same case etc....but fewer features on the CD618 - I think. The mechanism is the trusty CDM4/19, the decoder is SAA7310 and the DAC/filter is SAA7321/3. Do some searching on the CD624 and SAA7321/3 and you will find some relevant info.
Other machines that used this dac are the Rotel RCD865/965, QED Digit, Mission DAD5, Micromega Leader (a rebadged CD624) and some others.......
You have lots of options with this machine:
1. Keep the Bitstream DAC and improve the analogue stage.
2. Access the I2S after the filter and install an oversampled TDA1541/1543 dac.
3. Access the I2S before the filter (from the SAA7310 decoder) and install a non-oversampled TDA1541/1543 dac.
4. Improve it as a transport and use an external dac.
Send me a PM an I'll send you the manual for the CD624 and the datasheets for SAA7321 and SAA7310.
You won't find a lot of info on the CD618.....but fortunately for you...it is almost identical to the CD624. They share the same case etc....but fewer features on the CD618 - I think. The mechanism is the trusty CDM4/19, the decoder is SAA7310 and the DAC/filter is SAA7321/3. Do some searching on the CD624 and SAA7321/3 and you will find some relevant info.
Other machines that used this dac are the Rotel RCD865/965, QED Digit, Mission DAD5, Micromega Leader (a rebadged CD624) and some others.......
You have lots of options with this machine:
1. Keep the Bitstream DAC and improve the analogue stage.
2. Access the I2S after the filter and install an oversampled TDA1541/1543 dac.
3. Access the I2S before the filter (from the SAA7310 decoder) and install a non-oversampled TDA1541/1543 dac.
4. Improve it as a transport and use an external dac.
Send me a PM an I'll send you the manual for the CD624 and the datasheets for SAA7321 and SAA7310.
Hi,
Thanks for answering my thread.
You are right about the chipset in the cd618. I got some info, enough to figure out s/pdif interface and the I2S lines to the dac. More info is much apriciated.
There are many posebilites. At first I was going to use it as a plain transport, but there is room in it for a whole new dac! I can only see posetive things with tapping the I2S signal in the player insted of sending it, first, to a s/pdif transmitter, then recivier. See where I'm going? Also, some transistors are laying on my I2S line, hopefully I can figure that one out with the cd624 manual.
This player is pretty nice to work on, I know where I have everything for a change!
Fin: I understand from a old thread that you own a CD624. What do you think about it?
CDM4 is a great laser I think, I love the way it travels across the cd. No motors, just magnetism.
Best regards,
Magnus Kofoed
Ps, Sorry for this moring particulary bad english. It's way to early for me right now, we are talking pre-coffe time!
Thanks for answering my thread.
You are right about the chipset in the cd618. I got some info, enough to figure out s/pdif interface and the I2S lines to the dac. More info is much apriciated.
There are many posebilites. At first I was going to use it as a plain transport, but there is room in it for a whole new dac! I can only see posetive things with tapping the I2S signal in the player insted of sending it, first, to a s/pdif transmitter, then recivier. See where I'm going? Also, some transistors are laying on my I2S line, hopefully I can figure that one out with the cd624 manual.
This player is pretty nice to work on, I know where I have everything for a change!
Fin: I understand from a old thread that you own a CD624. What do you think about it?
CDM4 is a great laser I think, I love the way it travels across the cd. No motors, just magnetism.
Best regards,
Magnus Kofoed
Ps, Sorry for this moring particulary bad english. It's way to early for me right now, we are talking pre-coffe time!
Hi Magnus
I think that this is a player that you need to think carefully about. On the surface and after reading many comments about it (realating to Bitstream) the first idea is to disconnect the dac and install a non-oversampling tda1541/1543 dac. This is easy to do and would give a good result. However, I have taken a different approach and went looking for a similar TDA1541 machine. Eventually I found a Marantz CD60. Everything is similar except for the DAC - so now I have both options and can compare.
If you listen to Thorsten Loesch and CarlosFM, you will immediately ignore the existing dac and install a TDA dac - however, if you listen to Jean-Paul (who actually has a few CD624/634 machines) you will keep the existing dac and make some mods to it. He thinks it compares favourably with some TDA1541 machines.
I personally think that the TDA1541 machines sound better in stock form - but I know of two people who have improved the analogue output stage of a CD624 and found that it sounded very musical afterwards. I haven't modded mine yet - but I also have a Rotel RCD865 (same dac - better output stage) and it sounds excellent.
The CD624 was my fisrt real CD player and I bought it new in 1991....so I have a bit of emotional attachement to it and will always keep it. Eventually I will try to improve it and see what it is capable of. The analogue stage is definitely the wekest point.
The other real benefit of this machine is that the SPDIF output is handled by a separate chip - not the filter or decoder. This means that it can be improved as a transport quite effectively with that chip being reclocked by itself.
I think it would be interesting to take the existing dac to its limit.....then istall a TDA dac.....then decide. All of the work on the power supplies etc. would not be wasted as it would benefit both setups.
I think that this is a player that you need to think carefully about. On the surface and after reading many comments about it (realating to Bitstream) the first idea is to disconnect the dac and install a non-oversampling tda1541/1543 dac. This is easy to do and would give a good result. However, I have taken a different approach and went looking for a similar TDA1541 machine. Eventually I found a Marantz CD60. Everything is similar except for the DAC - so now I have both options and can compare.
If you listen to Thorsten Loesch and CarlosFM, you will immediately ignore the existing dac and install a TDA dac - however, if you listen to Jean-Paul (who actually has a few CD624/634 machines) you will keep the existing dac and make some mods to it. He thinks it compares favourably with some TDA1541 machines.
I personally think that the TDA1541 machines sound better in stock form - but I know of two people who have improved the analogue output stage of a CD624 and found that it sounded very musical afterwards. I haven't modded mine yet - but I also have a Rotel RCD865 (same dac - better output stage) and it sounds excellent.
The CD624 was my fisrt real CD player and I bought it new in 1991....so I have a bit of emotional attachement to it and will always keep it. Eventually I will try to improve it and see what it is capable of. The analogue stage is definitely the wekest point.
The other real benefit of this machine is that the SPDIF output is handled by a separate chip - not the filter or decoder. This means that it can be improved as a transport quite effectively with that chip being reclocked by itself.
I think it would be interesting to take the existing dac to its limit.....then istall a TDA dac.....then decide. All of the work on the power supplies etc. would not be wasted as it would benefit both setups.
Hi Fin,
Thanks for the datasheets and servicemanual, I got it all.
Yes, I hear what you are saying, and I will take a lot of time studing, looking over schematics and read others experience. I never rush things like these, on thing is that I'm low on money and lazy
, but most becouse I want to do it right the first time.
One nice thing also is that on my PCB the conector for the I2S lines from the SAA7310 is mounted on the PCB, I have a matching plug so one thing I can do is to try to use my existing TDA1541 DAC and bypass the S/PDIF interface. That would be more fair for the TDA1541 DAC. No soldering, only "jumpering".
I understand your emotional attachement to your CDP. If I had bought it new in '91, I think I would have kept it stock.
I agree it would be intersting to try both, I will try to do so. I will let you know of it works out.
Well, the first thing I will do is to change it's el-caps. If it is missing som bypass caps, I will also work that in.
Best regards,
Magnus
Thanks for the datasheets and servicemanual, I got it all.
Yes, I hear what you are saying, and I will take a lot of time studing, looking over schematics and read others experience. I never rush things like these, on thing is that I'm low on money and lazy
, but most becouse I want to do it right the first time.
One nice thing also is that on my PCB the conector for the I2S lines from the SAA7310 is mounted on the PCB, I have a matching plug so one thing I can do is to try to use my existing TDA1541 DAC and bypass the S/PDIF interface. That would be more fair for the TDA1541 DAC. No soldering, only "jumpering".
I understand your emotional attachement to your CDP. If I had bought it new in '91, I think I would have kept it stock.
I agree it would be intersting to try both, I will try to do so. I will let you know of it works out.
Well, the first thing I will do is to change it's el-caps. If it is missing som bypass caps, I will also work that in.
Best regards,
Magnus
Hi Magnus
Well, it seems like you will have the best of both worlds....especially with that emply space on the right side of the case. Maybe your TDA1541 dac can sit there permanently with with new RCA outputs.....one CDP with two dacs and two outputs.
Good luck with it and I will be watching for your results
Well, it seems like you will have the best of both worlds....especially with that emply space on the right side of the case. Maybe your TDA1541 dac can sit there permanently with with new RCA outputs.....one CDP with two dacs and two outputs.
Good luck with it and I will be watching for your results
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