Hi there
I have owned one of these fine TUbe output CD players for about 4 years now, all was well up until this morning and i would be very appreciative of any insights you may have. I bought a CD, that i played this morning and i could only hear the right channel.
Now stupidly I took the cover off thinking it was the tubes, that one had gone. So i got an old pair of Philips tubes that come with the CD player, and tried them, still no luck!.
on the control board and im no expert at these things, but there are 2 Burr brown opamps, set parralel to one another, i thought one of those might be the problem. There was also another small chip of the same size i think is the DAC chip. I took them out reseated them, changed them round , (only the opamps).
Maybe stupidly the wrong way round, the opamps have 8 pins 1- 4 5 - 8 I turned them round only because I forgot which way they went round. I usually do a little diagram before undertaking such work, but alas i didnt, fool!. Well the thing is it was the bloody Cd that was at fault. Overjoyed when I played my Meddle Album, In perfect stereo, was really happy. But to my horror... now at low levels i get a distortion sound and a slight ghosting of a high pitch sine wave around the 6th octave of a piano.
It cuts out after certain low passages break into higher volume. but ambient music is awash with this distorted tone. I know the tubes all work, I know the fuse is good, Im just wondering if i have damaged the opamps, or the circuit board.
heaven help me if i have , i have to send it back to holland to be fixed if its not a straight replacement
so guys any insight would be much appreciated
Andrew
I have owned one of these fine TUbe output CD players for about 4 years now, all was well up until this morning and i would be very appreciative of any insights you may have. I bought a CD, that i played this morning and i could only hear the right channel.
Now stupidly I took the cover off thinking it was the tubes, that one had gone. So i got an old pair of Philips tubes that come with the CD player, and tried them, still no luck!.
on the control board and im no expert at these things, but there are 2 Burr brown opamps, set parralel to one another, i thought one of those might be the problem. There was also another small chip of the same size i think is the DAC chip. I took them out reseated them, changed them round , (only the opamps).
Maybe stupidly the wrong way round, the opamps have 8 pins 1- 4 5 - 8 I turned them round only because I forgot which way they went round. I usually do a little diagram before undertaking such work, but alas i didnt, fool!. Well the thing is it was the bloody Cd that was at fault. Overjoyed when I played my Meddle Album, In perfect stereo, was really happy. But to my horror... now at low levels i get a distortion sound and a slight ghosting of a high pitch sine wave around the 6th octave of a piano.
It cuts out after certain low passages break into higher volume. but ambient music is awash with this distorted tone. I know the tubes all work, I know the fuse is good, Im just wondering if i have damaged the opamps, or the circuit board.
heaven help me if i have , i have to send it back to holland to be fixed if its not a straight replacement
so guys any insight would be much appreciated
Andrew
I don't own one but I could give you some pointers.
If you haven't already put your tubes that were working fine back in, do that.
If the opamp was in backwards you wouldn't get any sound, but if it's not seated in all the way or the legs are bent that may cause a problem.
The opamps that come with that player are the burr brown opa604 I believe. You can replace them with opa627-bp or opa227.
If you haven't already put your tubes that were working fine back in, do that.
If the opamp was in backwards you wouldn't get any sound, but if it's not seated in all the way or the legs are bent that may cause a problem.
The opamps that come with that player are the burr brown opa604 I believe. You can replace them with opa627-bp or opa227.
Thanks for your help Sbelyo,
yes spot on i now have a spare pair of opa604 as well, it seems that the opamps, are working as putting in the newer ones doesnt make no difference to the sound.
I actually have replaced the Opamps with some from Im thinking of the top of my head analogue solutions??. and it sounds better. (only for the sakes of soundstage Purposes, still have the same problem) I also have sourced a supplier of the DAC chips, as Its either the board thats not working properly, or i have damaged the DAC chip.
the tubes all work, light up!..2 sets
So i will find out hopefully soon, when the DAC chip comes from Thailand, If it works.
It does still work at mid to high volume, but as ever theres the sibilance and distortion of ambient peices, which Might be The DAC? If that gets put the wrong way round, which i did.
As i say im not a Amplifier DIY hobbyist, but im learning quickly a lot of do nots, any more insight about what could cause it??
Much appreciation
Andrew
yes spot on i now have a spare pair of opa604 as well, it seems that the opamps, are working as putting in the newer ones doesnt make no difference to the sound.
I actually have replaced the Opamps with some from Im thinking of the top of my head analogue solutions??. and it sounds better. (only for the sakes of soundstage Purposes, still have the same problem) I also have sourced a supplier of the DAC chips, as Its either the board thats not working properly, or i have damaged the DAC chip.
the tubes all work, light up!..2 sets
So i will find out hopefully soon, when the DAC chip comes from Thailand, If it works.
It does still work at mid to high volume, but as ever theres the sibilance and distortion of ambient peices, which Might be The DAC? If that gets put the wrong way round, which i did.
As i say im not a Amplifier DIY hobbyist, but im learning quickly a lot of do nots, any more insight about what could cause it??
Much appreciation
Andrew
I see.. I didn't think that you removed the dac. I suppose that would cause a problem. Those types of chips (opamps too) have a half circle molded into on end of the chip. The socket will have the same half circle showing you how to orient the chip.
I always seem to like the Burr Brown chips rather than the Analog Device chips. The BB's are warmer to my ears. The AD's are more analytical or truer to the ear. I've replaced the opamp in my SACD player with an AD and I have mixed emotions about it.
I always seem to like the Burr Brown chips rather than the Analog Device chips. The BB's are warmer to my ears. The AD's are more analytical or truer to the ear. I've replaced the opamp in my SACD player with an AD and I have mixed emotions about it.
Yes Im just hoping that it is the DAC. Thing is i usually do a diagram on paper how everything is orientated.
and contrary to my first post i, ahem did change the DAc round. I dont think i could sabotage it more if i tried
I usually can make modifications under instruction, and have fixed a few synths i own. But i buggered this up, hopefully not too badly.
Yes i know what you mean about burr brown, but this opamp sounded really punchy and detailed, its a DP27EP. I just thought i would buy a few that were compatible and this was the best, for my ears anyway.
and contrary to my first post i, ahem did change the DAc round. I dont think i could sabotage it more if i tried
I usually can make modifications under instruction, and have fixed a few synths i own. But i buggered this up, hopefully not too badly.
Yes i know what you mean about burr brown, but this opamp sounded really punchy and detailed, its a DP27EP. I just thought i would buy a few that were compatible and this was the best, for my ears anyway.
i just hope so, been a week now since i contacted the manufacturers in holland, seems they take a 2 week exodus, and shut the factory down. So looking forward to the DAC from Thailand, i think it is.I just looked inside my Rotel pre amp, it has about 4 opamps in their, you know what im thinking, "Without any prior clue what im doing", I could upgrade those opamps couldnt i??
What would make it sound better you reckon ?
well theres a mixture.
on the left near the headphone inputs is a JRC 4556D
what seems off the tone controls is a Signetics NE5532AN
and then in the centre just off the volume switch is another one exactly the same
Now near what im sure is the phono preamplifier stage is 2 Signetic NE5534AN, and two TL071CP.
I have from trying different opamps in the Cd player, have these Opamps, spare
BB OPA604AP times 2
BB OPA2134PA " "
BB OPA2604AP " "
AD OP27EP IC " "
Would any of these be of good improvement over the stock ones?
A bit irritating but it wont let me upload the photo of the insides of the Amp , even though the file is 400KB??
on the left near the headphone inputs is a JRC 4556D
what seems off the tone controls is a Signetics NE5532AN
and then in the centre just off the volume switch is another one exactly the same
Now near what im sure is the phono preamplifier stage is 2 Signetic NE5534AN, and two TL071CP.
I have from trying different opamps in the Cd player, have these Opamps, spare
BB OPA604AP times 2
BB OPA2134PA " "
BB OPA2604AP " "
AD OP27EP IC " "
Would any of these be of good improvement over the stock ones?
A bit irritating but it wont let me upload the photo of the insides of the Amp
, even though the file is 400KB??My AH 4000, Cd Player, Stopped working on 1 Channel , I got a Friend to open it up, and He Said That The Small Little Digital to Analog Board is Very Loose, and Might need Replacing I dont understand why it Does not work on one Channel on The Analog side and it works on DIGITAL output. Please Help me.
Kind Regards
Francis Jansz
Kind Regards
Francis Jansz
AH TJoeb Cd 4000 No OUTPUT ON 1 ANALOG CHANNEL
Dear Friend,
My DIGITAL OUTPUTS works on both Channels Perfectly,
But I have a Problem on 1 ANALOG Channel , How can I get it to work ,
I am not a technician and got no idea to get it going, Please help me, I tried contacting Holland, and did not get any replies from them , I even tried to phone them and They dont speak ENGLISH.
Looks like that I may have wasted my Money And Bought The Seamens Tubes From Them for over $250 USD + Postage cost,
I need some help
Kind Regard,s
Francis Jansz
Dear Friend,
My DIGITAL OUTPUTS works on both Channels Perfectly,
But I have a Problem on 1 ANALOG Channel , How can I get it to work ,
I am not a technician and got no idea to get it going, Please help me, I tried contacting Holland, and did not get any replies from them , I even tried to phone them and They dont speak ENGLISH.
Looks like that I may have wasted my Money And Bought The Seamens Tubes From Them for over $250 USD + Postage cost,
I need some help
Kind Regard,s
Francis Jansz
Most (but not all) the problems on the Ah Tjoeb 4000 are due to leaky electrolytic caps on the small D/A board corroding and breaking pcb tracks running below the caps. It is not visible without removing the caps.
I would start with this:
1. Carefully remove the D/A board from the CD player. (unplug the two connectors and lift the card)
2. Unsolder and remove the (5) elcaps around the voltage regulator.
3. Check the pc tracks under the caps for corrosion and breaking (use a magnifier). Clean and repair broken tracks if necessary. This is the most difficult part of the process as the pc tracks are very thin. You'll need a very small soldering tip and thin wire. Be very careful and don't break or short adjacent tracks.
4. Replace all the electrolytic caps with new ones.
5. Re-install the board in the CD player.
This will cure about 85% of the faults in the D/A converter board. If not, you have a more serious problem and probably will need the assistance from an experienced tech for diagnosis and repair.
I would start with this:
1. Carefully remove the D/A board from the CD player. (unplug the two connectors and lift the card)
2. Unsolder and remove the (5) elcaps around the voltage regulator.
3. Check the pc tracks under the caps for corrosion and breaking (use a magnifier). Clean and repair broken tracks if necessary. This is the most difficult part of the process as the pc tracks are very thin. You'll need a very small soldering tip and thin wire. Be very careful and don't break or short adjacent tracks.
4. Replace all the electrolytic caps with new ones.
5. Re-install the board in the CD player.
This will cure about 85% of the faults in the D/A converter board. If not, you have a more serious problem and probably will need the assistance from an experienced tech for diagnosis and repair.
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I know this is a very old thread, but did you ever figure out the problem? I thought I was onto something after reading Tubologic's post but I don't have the upsampler board so I don't think it applies to my unit. I have a similar problem where one channel is distorted. The distorted channel actually sounds louder compared to the other channel.
Dear Andrew.Hi there
I have owned one of these fine TUbe output CD players for about 4 years now, all was well up until this morning and i would be very appreciative of any insights you may have. I bought a CD, that i played this morning and i could only hear the right channel.
Now stupidly I took the cover off thinking it was the tubes, that one had gone. So i got an old pair of Philips tubes that come with the CD player, and tried them, still no luck!.
on the control board and im no expert at these things, but there are 2 Burr brown opamps, set parralel to one another, i thought one of those might be the problem. There was also another small chip of the same size i think is the DAC chip. I took them out reseated them, changed them round , (only the opamps).
Maybe stupidly the wrong way round, the opamps have 8 pins 1- 4 5 - 8 I turned them round only because I forgot which way they went round. I usually do a little diagram before undertaking such work, but alas i didnt, fool!. Well the thing is it was the bloody Cd that was at fault. Overjoyed when I played my Meddle Album, In perfect stereo, was really happy. But to my horror... now at low levels i get a distortion sound and a slight ghosting of a high pitch sine wave around the 6th octave of a piano.
It cuts out after certain low passages break into higher volume. but ambient music is awash with this distorted tone. I know the tubes all work, I know the fuse is good, Im just wondering if i have damaged the opamps, or the circuit board.
heaven help me if i have , i have to send it back to holland to be fixed if its not a straight replacement
so guys any insight would be much appreciated
Andrew
On my Tjorb 400. I don't get any Sound on 1 Channel . O think that my Fav Chip is not working. Could you send me the Name and the web site of They Taiwan Supplier that you bought the DAC Chip from so that I too can order one.
Your help will be Appreciated.
Kind Regards
Francis Jansz
Australia