I followed your advice and checked all the power cables going from the PS PCB onto the Analog one. They checked OKAY; closely matched the readings on the PCB.
I also took a very carefully reading of the tubes right now [see my ugly drawing of the tubes]. When examing the PS PCB, I realised that some of the OS-CON were not well soldered. I re-solder them before I took the tubes readings.
Are the readings normal? If they are normal, I don't need to go through all the trouble ... ha..ha... :
Tossing the CD out of the window? It should be okay if you do it in TEXAS, ha..ha... In Hong Kong, if I do that, I will be quite certain that someone will got killed down the road ..... That is why in Hong Kong we use a different term --- dump it into the sea.
That is strange. We have FOUR CD 33 here that give off similiar readings. We don't have Voltage readings for Tube 1 Pin 2 and 8 whereas yours have. You have more readings for the second tube (closer to the DAC) as well.
I am just an idiot in this field. Does this suggest that there is actually something wrong with the CD 33 design? As you by-passed the Op-amp part, will this affect the tubes' readings?
I will be going back to China next week. I really hope to acquire the schematic for the CD33. Let's see if my friend up there can help. With the schematic, I think experts like you may give us more insight into this issue.
I re-solder several points in the PS PCB and re-run the unit for a couple of hours. I realised that the "distortion" in High Pitch maybe caused by me using the Telefunken EL84 tubes. They tend to exaggerate the sound too much in my ASL amp. When I change the tubes back to GE 6L6G, the problem seems to be gone.
Will continue to investigate when I have more time this week.
I hope you have a good night sleep. I couldn't sleep well last night and ended up with an headache this whole day up to now.
I took the measurement WITHOUT the tubes. At first, I tried to do it with the tubes on. I place the pin / probe at the soldering point. Then I realised it is kind of dangerous. Therefore, I took all those readings with the tubes pulled out.
I just finished my FINAL (hopefully it is) readings. This time, I put the tubes back on. Not only that, I also tried out the different tubes I have.
You can see from the KEY I put down on the paper. There are TWO CD 33 for comparisons. First, mine using the Bendix 2C51 tubes. Then comes my friend's CD 33 with the same Bendix type 2C51 and finally the Chinese 6N3 tubes. They produced interesting and very different results.
t. or WINDWSS, can you spot any possible problems here with these readings?
Your wordings are really comforting. Glad to hear that finally my CD is at least okay.
As mentioned in the previous post, I re-soldered several points on the PS PCB before I get back the "normal" sound I have. I think the problem arise mainly because I switched to another soldering iron and I am not used to that tip.
Will double check on the Heatsink there. Thanks for your help! :wink:
No wonder you were so "quiet" these days. Ha..ha... you were busy modifying your Cayin 15a. No wonder.
Been VERY busy these two weeks. My CD 33 is okay now after I changed the White / Grey Flat Cable. The Chinese Sales gave me two of those free of charge.
I bought a LITE DAC-AH today in China. I was hoping to use the board in the CD33 but need to figure out HOW it should be done first. "t" is telling / helping me in the other thread.
To my surprise, the LITE DAC-AH standalone makes a lot of difference. I plug it in to the Matisse and my wife says "Wow ... what happened?" The Depth, Openess and Clarity all improved. As the Matisse got more than ONE input, I can switch between using and not using the DAC by the turn of the knob. Even my daughter feels a lot of difference there. Just hope I can inplant the PCB into the CD 33 later.
Will try to understand more of your Cayin modification after I finished marking all the exam / tests.
Ha..ha.. I am also NEW; just join this forum in April or so.
I am not an "Electronics" man but I can share with you some of my experience.
The CD33 to ME is an experiment only. It produces acceptable sound, especially female vocal at a very reasonable price. But if you like other types of music as well, e.g. classical ... it performs pretty poor. If you want a full range CD player, I would say you have to find something else rather then the CD33.
The LITE DAC-AH brings in some improvement. I have it as external now as I don't have the time to put it inside the CD 33. I got the LITE at $ 650 and it shows some improvements only (for certain CD but not all).
Follow the other links here and you can see what Koifarm, t, KIKO and the others had done / suggested to improve the CD33. These guys are more knowledgable than I am for SURE ....
If you need further information, just drop me a note.
I got a pair of Bendix, which is pretty good. I am now switching to WE396a as I got it some time ago. To me, the two pairs sound very much alike.
CD 33 remote? I can check with the Chinese Sales I deal with. Don't expect an answer until one week from now as he checks mail not very often. We will probably go again in December, if the price is right, I can get it for you.
You can still mail me the remote if you want me to test it out for you. OR you can find someone who has a CD 33/66/88 and test it out. They use the same remote.
If you want to mail it to me, make sure you put INSURANCE on it. I lost two packages with the Royal Mail in the past.
We should be going up next week or the week after ....
I will send you my address in my next email to you.
If your remote can't arrive on time, I can get you a new one and once your problematic one gets here, I should be able to get it fixed for you as well.
My WHITE cat is a Angora. My Black cat is a Persian.
It looks like many Hi Fi Fans are CAT and Aquatic Plant Lovers.... ha..ha...
MHZS changed their PCB once or twice. The OLD ones are direct soldering. They use better quality capacitors on the other hand and better cables for connection.
The CD33 I have got a Dip 8 socket for the OPA2604. However, the capacitors are of a poorer grade, and so is the cables.
Well, I can't tell whether it is genuine BB. I changed it to a pair of OPA627AM anyway. The improvement is very significant.
Finally, I followed Koifarm's advice, completely by-passed the OPAMP section with the DAC-AH installed inside the CD player. VERY impressive performance.
I don't think they will go back to the previous version PCB. Mine is 2006 Aug or so ... there is already a socket for the OPAMP already.
I used BB OPA 2107 at first. Pretty good improvement over the original 2604 (so called). However, if you haven't modified other components, the 2107 gives off too high pitch (even distortion) at certain times (female vocals).
Finally I used a pair of 627AM. But now, my CD 33 is dead and I am selling it off as scrap / spare parts.
I used to have two dogs too. When cats were brought up together with dogs, it is always the cats which bully the dogs. BEST example =Garfield & Odie
This is very nice of you to share your experience with the MHZS players here.
Have you figured out what actually caused the "can't read" problem with these MHZS players?
Recall my last one, I put in the disc the the disc even turn ANTI-Clockwise instead of the usual clockwise .... never got any experience like this with other CD players.
I really like my CEC player. It gives wonderful music. I have heard that this Belt Drive player is VERY expensive in Europe.
The Shanling T-100se is a nice CD player as well. One of my friends got one and I listened to it as well. Very pleasing sound.
My CEC is a belt drive player. It is good for music and vocals. But I think it may not be too good for classical.
I think you bypass the OPAMPS in your 100se as well, right? I tried to look back at the photos you put up last year but they are too small in size for me to recommend my friend to modify his 100se.
Can you show us some larger size photos of your modifications with the 100se please?
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