Different OPAMP in my case.
Thanks very much!
I've found in my 963SA, besides AD8032 and AD8022, there are still AD825 OP Amp, should be for center, sub-woofer and surround channel, instead of LM833/ 5532. It use mainly Rubycon normal caps. My 963SA should be the first batch with batch number 691.
Anyway, I've changed some Op Amp to AD8620 and the sound is pleasing to me!
Thanks very much!
I've found in my 963SA, besides AD8032 and AD8022, there are still AD825 OP Amp, should be for center, sub-woofer and surround channel, instead of LM833/ 5532. It use mainly Rubycon normal caps. My 963SA should be the first batch with batch number 691.
Anyway, I've changed some Op Amp to AD8620 and the sound is pleasing to me!
Downgrades
I have found several areas where bypassing actually makes things worse.
During the video mods, I found that bypassing the SMPS output filter capacitors #2235, 2285 produced occasional white squares across the image.
During the audio mods, I found that bypassing capacitors #2633, 2635, 2637 added a glassy sound to the midrange.
In each case I had to remove the bypass capacitors. Instead I did nothing or substituted a BG capacitor.
I think that these problems are caused by the long unshielded ribbon cables which carry both power and the digital datastream. Bypass capacitors will cause HF currents to flow on these cables either radiating noise or contaminating the digital datastream.
It may be desirable to shield these cables.
In a similar vein, if the progressive video section is not being used, it could be removed along with its ribbon cable, and a partition could be installed between the main board and the audio board.
I have found several areas where bypassing actually makes things worse.
During the video mods, I found that bypassing the SMPS output filter capacitors #2235, 2285 produced occasional white squares across the image.
During the audio mods, I found that bypassing capacitors #2633, 2635, 2637 added a glassy sound to the midrange.
In each case I had to remove the bypass capacitors. Instead I did nothing or substituted a BG capacitor.
I think that these problems are caused by the long unshielded ribbon cables which carry both power and the digital datastream. Bypass capacitors will cause HF currents to flow on these cables either radiating noise or contaminating the digital datastream.
It may be desirable to shield these cables.
In a similar vein, if the progressive video section is not being used, it could be removed along with its ribbon cable, and a partition could be installed between the main board and the audio board.
Hi Eganz,
I have been following your posts here with great interest and very appreciate you sharing your mods.
I can understand upgrading capacitors in "most" cases can result in improvements but bypassing and it seems you found out can cause more probelms. Below is a link to discussion in AA
http://db.audioasylum.com/cgi/m.pl?...highlight=bypass+capacitor+signal&r=&session=
were you just bypassing every capacitor on the board or did you have a plan based on the circuit diagarm?
The capacitor you chose "metalized polyester" is not the best out there, is there other metalized like polyproplyn that can fit the space?
I am looking forward to your comments.
Regards
Amir
I have been following your posts here with great interest and very appreciate you sharing your mods.
I can understand upgrading capacitors in "most" cases can result in improvements but bypassing and it seems you found out can cause more probelms. Below is a link to discussion in AA
http://db.audioasylum.com/cgi/m.pl?...highlight=bypass+capacitor+signal&r=&session=
were you just bypassing every capacitor on the board or did you have a plan based on the circuit diagarm?
The capacitor you chose "metalized polyester" is not the best out there, is there other metalized like polyproplyn that can fit the space?
I am looking forward to your comments.
Regards
Amir
After the last set of mods (stage three) there was an improvement in resolution, but also a decrease in musicality.
So I removed the bypasses from #2317, 2319, and 2314.
I also replaced the 10 uF caps #2612 and 2620 with 100uF BG to improve filtering of SMPS power supply spikes.
This has recovered the musicality.
So I removed the bypasses from #2317, 2319, and 2314.
I also replaced the 10 uF caps #2612 and 2620 with 100uF BG to improve filtering of SMPS power supply spikes.
This has recovered the musicality.
Amir,
Yes, these modifications are based on studying the circuit diagram, previous experience with consumer electronics modifications, and also the results and suggestions of others who have worked on this player (e.g. this thread). This is a work in progress, and there is a certain amount of trial and error involved. If you really want to get serious, you should also use a high-speed oscilloscope.
I started with the goal of fixing and improving the video sections.
This involved bypassing of the digital video circuitry, and upgrades to the power supply.
Certain design errors were corrected. The bypassing was done with physically small capacitors that fit easily on the boards (5mm pitch).
The power supply upgrades mostly involved replacement with same value black gate capacitors.
Now I have moved on to modifications in the audio sections.
The initial work involved bypassing of the digital chips, where physically small capacitors are again desirable.
The only true signal path change was to replace the output coupling capacitors with high-quality nonpolar black gate type N capacitors.
For the 470 uF capacitors directly at the +/- 8V power inputs for the I/V and output op amps, black gate STD caps were used.
Certainly, metallized polypropylene capacitors (e.g. MKP) are very high-quality and are excellent for use in audio circuitry. I ordered some for this project, but by mistake I ended up with ones that were physically too large, and so I need to order some new ones.
Yes, these modifications are based on studying the circuit diagram, previous experience with consumer electronics modifications, and also the results and suggestions of others who have worked on this player (e.g. this thread). This is a work in progress, and there is a certain amount of trial and error involved. If you really want to get serious, you should also use a high-speed oscilloscope.
I started with the goal of fixing and improving the video sections.
This involved bypassing of the digital video circuitry, and upgrades to the power supply.
Certain design errors were corrected. The bypassing was done with physically small capacitors that fit easily on the boards (5mm pitch).
The power supply upgrades mostly involved replacement with same value black gate capacitors.
Now I have moved on to modifications in the audio sections.
The initial work involved bypassing of the digital chips, where physically small capacitors are again desirable.
The only true signal path change was to replace the output coupling capacitors with high-quality nonpolar black gate type N capacitors.
For the 470 uF capacitors directly at the +/- 8V power inputs for the I/V and output op amps, black gate STD caps were used.
Certainly, metallized polypropylene capacitors (e.g. MKP) are very high-quality and are excellent for use in audio circuitry. I ordered some for this project, but by mistake I ended up with ones that were physically too large, and so I need to order some new ones.
On their Website, Acoustic Reality has some news concerning their upgrade of the DVD 963:
http://www.acoustic-reality.com/news/news.htm
Quote:
"DVD963SA is a CD/SACD/DVD player with 192kHz/24bit CD upsampling
With permission and in agreement with Philips-Denmark, Acoustic Reality is now able to offer a super modified version of the Philips DVD963SA, which is the newest generation (WAY FAR BETTER than for example the old SACD1000) multi-channel SACD/DVD player with 192kHz/24bit CD upsampling and DSD (Data Stream Direct) Super Audio CD. Even when it is sounding okay without modifications, the player is sounding so much better when it is modified that you will not believe it is possible to obtain that analog sound from any CD player and certainly not to this ridicules low price! The DVD963SA contain the new state-of-the-art AD1955 Digital-to-Analog Converter from Analog Device, which supports 24-Bits, up to 192 kHz Sample Rate PCM Audio Data and SACD bit-stream. The AD1955 is designed for use in high-end SACD players.
You may be able to purchase the player cheaper on the Internet than we can buy the player from Philips-Denmark. Therefore we also offer the modications without you have to purchase the player from us. It is important to note that players purchased outside Europe are not equal to players that are purchased in Europe, but the main board (with the sound circuit) is equal. That may explain some of the price differences!
Here in Scandinavia the suggested retail price of the player is DKK 4995.
We sell it for DKK 3995 without modifications.
We offer three type of modifications. Level one mod is priced to DKK 1439 / EURO 199, level two mod is priced to DKK 3699 / EURO 499 and level three mod is priced to DKK 5999 / EURO 799.
Level one mod contain a netfilter and a new DC-coupled analog stereo output stage, which has a distortion of just 0.00009%. We believe it is the lowest distortion of any CD output stage in the World. The level one mod will give you SO MUCH sound for the money that no one would believe it.
Level two mod is fully super modified for stereo. It also contain a new power supply to the analog output, which has the dead silence of batteries. The new power supply has been developed at Acoustic Reality. The level two mod is for hardcore audiophiles.
Level three mod is equal to level two, but all 6 surround channels have been fully modified.
Forget to upgrade the clock of this player, while it may work in other players without upsampling. The reason why you don't have to think about a clock upgrade is because this player has 192kHz/24bit upsampling, which is way far better than any 44kHz/16bit player with a clock upgrade ever will be able to perform. The already made super clock from Philips is absolutely okay and it will give no sound improvement to upgrade other than it will cost money.
On the front the player also carry Acoustic Reality's logo (made in aluminium) to show the player contain QUALITY modifications performed by a skilled and professional company (it also shows it is not kitchen-table or DIY modifications). "
http://www.acoustic-reality.com/news/news.htm
Quote:
"DVD963SA is a CD/SACD/DVD player with 192kHz/24bit CD upsampling
With permission and in agreement with Philips-Denmark, Acoustic Reality is now able to offer a super modified version of the Philips DVD963SA, which is the newest generation (WAY FAR BETTER than for example the old SACD1000) multi-channel SACD/DVD player with 192kHz/24bit CD upsampling and DSD (Data Stream Direct) Super Audio CD. Even when it is sounding okay without modifications, the player is sounding so much better when it is modified that you will not believe it is possible to obtain that analog sound from any CD player and certainly not to this ridicules low price! The DVD963SA contain the new state-of-the-art AD1955 Digital-to-Analog Converter from Analog Device, which supports 24-Bits, up to 192 kHz Sample Rate PCM Audio Data and SACD bit-stream. The AD1955 is designed for use in high-end SACD players.
You may be able to purchase the player cheaper on the Internet than we can buy the player from Philips-Denmark. Therefore we also offer the modications without you have to purchase the player from us. It is important to note that players purchased outside Europe are not equal to players that are purchased in Europe, but the main board (with the sound circuit) is equal. That may explain some of the price differences!
Here in Scandinavia the suggested retail price of the player is DKK 4995.
We sell it for DKK 3995 without modifications.
We offer three type of modifications. Level one mod is priced to DKK 1439 / EURO 199, level two mod is priced to DKK 3699 / EURO 499 and level three mod is priced to DKK 5999 / EURO 799.
Level one mod contain a netfilter and a new DC-coupled analog stereo output stage, which has a distortion of just 0.00009%. We believe it is the lowest distortion of any CD output stage in the World. The level one mod will give you SO MUCH sound for the money that no one would believe it.
Level two mod is fully super modified for stereo. It also contain a new power supply to the analog output, which has the dead silence of batteries. The new power supply has been developed at Acoustic Reality. The level two mod is for hardcore audiophiles.
Level three mod is equal to level two, but all 6 surround channels have been fully modified.
Forget to upgrade the clock of this player, while it may work in other players without upsampling. The reason why you don't have to think about a clock upgrade is because this player has 192kHz/24bit upsampling, which is way far better than any 44kHz/16bit player with a clock upgrade ever will be able to perform. The already made super clock from Philips is absolutely okay and it will give no sound improvement to upgrade other than it will cost money.
On the front the player also carry Acoustic Reality's logo (made in aluminium) to show the player contain QUALITY modifications performed by a skilled and professional company (it also shows it is not kitchen-table or DIY modifications). "
Audio mods stage four
I finally installed a separate power supply for the op amps.
The result is a dramatic improvement - the player is taken to the new level.
Music is more relaxed, but layered and with more detail. The improvement is across-the-board and is very worthwhile.
SACD's are glorious.
I should have done it earlier, but I got distracted trying to see how far I could go with the capacitor bypassing and replacement program.
Actually, I first removed the progressive scan board and cable.
The main board has some empty spaces for surface mount capacitors, so I added 47 uF BG and 1uF ceramic at #2910 (+5V), and 100 uF BG at #2912 (+12V) on the top of the board. I removed the unused 833 op amp #7401.
I then added a +/- 9VAC, 1.1 A toroidal transformer (digikey #TE62041-ND), diode bridge, and 0.25A fuse wired to 2x 1000uF BG caps, NJM7808FA and NJM7908FA +8V and -8V regulators, and then 2x 470uF BG caps.
This was wired in by removing the original +8V regulator #7601, removing caps #2912, 2913, and removing jumper #4604 to isolate the +8V OP AMP and -8VA lines. This provides a much quieter supply to the op amps and DAC.
(Amir, digikey sells a small .12UF MKP film cap #BC2056-ND)
I finally installed a separate power supply for the op amps.
The result is a dramatic improvement - the player is taken to the new level.
Music is more relaxed, but layered and with more detail. The improvement is across-the-board and is very worthwhile.
SACD's are glorious.
I should have done it earlier, but I got distracted trying to see how far I could go with the capacitor bypassing and replacement program.
Actually, I first removed the progressive scan board and cable.
The main board has some empty spaces for surface mount capacitors, so I added 47 uF BG and 1uF ceramic at #2910 (+5V), and 100 uF BG at #2912 (+12V) on the top of the board. I removed the unused 833 op amp #7401.
I then added a +/- 9VAC, 1.1 A toroidal transformer (digikey #TE62041-ND), diode bridge, and 0.25A fuse wired to 2x 1000uF BG caps, NJM7808FA and NJM7908FA +8V and -8V regulators, and then 2x 470uF BG caps.
This was wired in by removing the original +8V regulator #7601, removing caps #2912, 2913, and removing jumper #4604 to isolate the +8V OP AMP and -8VA lines. This provides a much quieter supply to the op amps and DAC.
(Amir, digikey sells a small .12UF MKP film cap #BC2056-ND)
Thanks Eric for the great info.
Do you think the 1 volt difference between the transformer out and the regulated supply (8v) is enough?
Are you not using the video section (you removed the progressive scan board) of the player? Is it possible to leave the board in with your modifications?
Thanks
Regards
Amir
Do you think the 1 volt difference between the transformer out and the regulated supply (8v) is enough?
Are you not using the video section (you removed the progressive scan board) of the player? Is it possible to leave the board in with your modifications?
Thanks
Regards
Amir
Eric,
either I am missing something or the markings are different on the boards. I can not find capacitors 2912 and 2913 on the audio board. If you are refering to the capacitors next to(to the right of) the 7601 regulator, on my board they are marked 2613. I also could not find the jumper 4604.
What is the original -8V regualtor? does that need to be removed/replaced.
Thanks
Amir
either I am missing something or the markings are different on the boards. I can not find capacitors 2912 and 2913 on the audio board. If you are refering to the capacitors next to(to the right of) the 7601 regulator, on my board they are marked 2613. I also could not find the jumper 4604.
What is the original -8V regualtor? does that need to be removed/replaced.
Thanks
Amir
Amir,
Actually, the player is taken to a new level.
9 VAC -> 13 VDC.
I am using this particular machine only for audio. You can leave in the progressive scan board.
#2910 and #2912 are located on the main board, which also benefits from bypassing / increased capacitance.
You are correct that I actually removed #2612, 2613 on the AV board.
Jumper #4604 is tiny and is next to the negative side of cap #2619 on the top of the AV board. When you remove this, you isolate the -8VA line for the op amps. The original -8V regulator is still used for various digital pulldowns.
The new +8V and GND were wired onto the surface mount pads from the +8V reg, and the new -8V was wired to cap #2445.
EG
Actually, the player is taken to a new level.
9 VAC -> 13 VDC.
I am using this particular machine only for audio. You can leave in the progressive scan board.
#2910 and #2912 are located on the main board, which also benefits from bypassing / increased capacitance.
You are correct that I actually removed #2612, 2613 on the AV board.
Jumper #4604 is tiny and is next to the negative side of cap #2619 on the top of the AV board. When you remove this, you isolate the -8VA line for the op amps. The original -8V regulator is still used for various digital pulldowns.
The new +8V and GND were wired onto the surface mount pads from the +8V reg, and the new -8V was wired to cap #2445.
EG
Corrected Audio Mod stage four:
Actually, I first removed the progressive scan board and cable.
The main board has some empty spaces for surface mount capacitors, so I added 47 uF BG and 1uF ceramic at #2910 (+5V), and 100 uF BG at #2912 (+12V) on the top of the board. I removed the unused 833 op amp #7401.
I then added a +/- 9 VAC, 1.1 A toroidal transformer (digikey #TE62041-ND), diode bridge, and 0.25 A fuse wired to 2x 1000uF BG caps, NJM7808FA and NJM7908FA +8V and -8V regulators, and then 2x 470uF BG caps.
This was wired in by removing the original +8V regulator #7601, removing caps #2612, 2613, and removing jumper #4604 to isolate the +8V OP AMP and -8VA lines. This provides a much quieter supply to the op amps and DAC.
Actually, I first removed the progressive scan board and cable.
The main board has some empty spaces for surface mount capacitors, so I added 47 uF BG and 1uF ceramic at #2910 (+5V), and 100 uF BG at #2912 (+12V) on the top of the board. I removed the unused 833 op amp #7401.
I then added a +/- 9 VAC, 1.1 A toroidal transformer (digikey #TE62041-ND), diode bridge, and 0.25 A fuse wired to 2x 1000uF BG caps, NJM7808FA and NJM7908FA +8V and -8V regulators, and then 2x 470uF BG caps.
This was wired in by removing the original +8V regulator #7601, removing caps #2612, 2613, and removing jumper #4604 to isolate the +8V OP AMP and -8VA lines. This provides a much quieter supply to the op amps and DAC.
Transport noise
The player is now very musical, and I have been enjoying lots of CDs and SACDs.
Unfortunately, there is sometimes significant transport noise on some disks.
The periodic soft ticking sound on CDs has already been discussed.
More annoying is a strong vibration on the initial tracks of certain DVDs or SACDs.
Any suggestions for how to eliminate these vibrations?
The player is now very musical, and I have been enjoying lots of CDs and SACDs.
Unfortunately, there is sometimes significant transport noise on some disks.
The periodic soft ticking sound on CDs has already been discussed.
More annoying is a strong vibration on the initial tracks of certain DVDs or SACDs.
Any suggestions for how to eliminate these vibrations?