After playing for several days just lying on the table I finally found some time to mount everything on a board. I needed to deal with the issues my headphone amp was having with the new Micromega DAC1, first.
Everything is still the way it came out of the 'E51. I used some scrap chipboard I had lying around (I know, not the best choice). First thing I noticed was how noisy this Sanyo mechanism is now that it is solidly fixed to the board (my hearing is quite sensitive to the hissing noise this thing makes). I always thought that the Sony transport (KSS-150) was noisy (the Philips CDM12.4 in my Primare D20 is hardly audible), but this is even worse.
I can't say that I noticed any difference between lying loose on the table or sitting on "the plank" (yet).
Next step: build a PSU with a 7808 and throw out the main/audio board.
Everything is still the way it came out of the 'E51. I used some scrap chipboard I had lying around (I know, not the best choice). First thing I noticed was how noisy this Sanyo mechanism is now that it is solidly fixed to the board (my hearing is quite sensitive to the hissing noise this thing makes). I always thought that the Sony transport (KSS-150) was noisy (the Philips CDM12.4 in my Primare D20 is hardly audible), but this is even worse.
I can't say that I noticed any difference between lying loose on the table or sitting on "the plank" (yet).
Next step: build a PSU with a 7808 and throw out the main/audio board.
Re: Integrating external DAC with CD Player?
Hi westers151.
You can take feed from rectifier then add new regulator and output capacitor. Be aware that it will afects first capacitor after the rectifier, so, increasing one may be necessary.
Better option is to add yet another rectifier feeding from trafo, and then build new regulation-filter unit based on 7805.
It is essential that trafo able to deliver enough current for both.
However, I am wondering what benefits one may get by mounting this DAC inside the the box together with JVC drive, since original PCB has one.
I can see number of facts against doing that. Can't see any benefit.
Just one to mention: that DAC kit is nice base for standalone DAC. Spending it you are loosing it, and probably you are going to make this CD clone sounding worse.
westers151 said:
Hi westers151.
You can take feed from rectifier then add new regulator and output capacitor. Be aware that it will afects first capacitor after the rectifier, so, increasing one may be necessary.
Better option is to add yet another rectifier feeding from trafo, and then build new regulation-filter unit based on 7805.
It is essential that trafo able to deliver enough current for both.
However, I am wondering what benefits one may get by mounting this DAC inside the the box together with JVC drive, since original PCB has one.
I can see number of facts against doing that. Can't see any benefit.
Just one to mention: that DAC kit is nice base for standalone DAC. Spending it you are loosing it, and probably you are going to make this CD clone sounding worse.
Dzuvela
Thanks for the reply and I was starting to come to the same conclusion about a seperate rectifier/regulator for the DAC.
Several reasons why I wanted to put this seperate DAC into the case of the Shigaclone:
Thanks for the reply and I was starting to come to the same conclusion about a seperate rectifier/regulator for the DAC.
Several reasons why I wanted to put this seperate DAC into the case of the Shigaclone:
- Space saving - no need for yet another case to be made and put onto a shelf
- Reduce power supplies and number of leads coming from the mains
- Add a little extra weight to the shigaclone case
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As you can see the reasons are purely cosmetic/convenience rather than technical.
However I am confused about your comment
I have been lead to believe that the onboard DAC is very poor, hence the reason for the digital signal mod to take a signal to an external DAC. My idea is to take the digital signal from the CD board and feed that into the DAC board I will be getting. So, in effect I will be feeding the signal to an external DAC, but that DAC will be housed in the same case as the cd transport.
Why would the above be bad?
I do not understand what you mean with this comment:
Can you explain please.
In all of this my idea is to first build both the DAC and the CD transport in stock form - no alterations (apart from power supplies). I will then be able to get a base reference for the sound.
Then I would progress to make the documented alterations to the DAC board (higher frequency sampling, etc) and see how this improves the stock CD player. If the sound is good I may leave the CD player as standard. If I feel it still needs improvement I will then make alterations to the CD player, one by one, as documented here.
westers151 said:
Ok.
Here is go.
1. Lampucera project is dedicated project for stand alone DAC with superb sound. (I have one not tweaked yet) It is handy to have one standalone DAC for different purpouses. If you integrate it with other unit, you are loosing option of having standalone DAC for any purpose you may need tomorrow.
2. Adding it in same box with drive, where another instance of electronic already doing the job, actually you are adding more noise sources (electronic noise).
Interconnection between existing board and new board should be done at the TTL or SPDIF level. You will need for that at least few centimeters of some kabel, lead. This can be quite a problem due to the high frequency nature of signal and impendance match all of that in quite noisy environment.
I am almost sure that result will be bad. There are still problems with PSU and space.
3. If you would make "lampucera" separatly, you will be able to compare sound of CD drive with own DAC, or using external one by coax or TOSLINK without noisy interaction of two boards.
Thanks dzuvela, I see where you are coming from.
Out of all of those issues I think the electrical interference will be the biggest one. I could build a big enough case to alllow for Spdif sockets for the DAC and connect that to the spdif out socket for the CD. This would be an external connection (i.e, run a cable from the CD socket on the outside of the case to the SPDIF input socket (on the outside of the case) for the DAC. That would possibly do away with the interconnection issue, and also allow me to use the DAC for other uses.
However it doesn't do away with the electronic noise issues - I had assumed that the DAC and CD circuits would co-habit without noise issues, but I should have known better than to assume
Seperate case it is, and it also makes my decision for an external PSU much easier for my Gainclone, Shigaclone and DAC. I'll put all 3 transformers in a seperate enclosure and run seperate DC feeds to all 3 devices.
Thanks for the advice.
Out of all of those issues I think the electrical interference will be the biggest one. I could build a big enough case to alllow for Spdif sockets for the DAC and connect that to the spdif out socket for the CD. This would be an external connection (i.e, run a cable from the CD socket on the outside of the case to the SPDIF input socket (on the outside of the case) for the DAC. That would possibly do away with the interconnection issue, and also allow me to use the DAC for other uses.
However it doesn't do away with the electronic noise issues - I had assumed that the DAC and CD circuits would co-habit without noise issues, but I should have known better than to assume
Seperate case it is, and it also makes my decision for an external PSU much easier for my Gainclone, Shigaclone and DAC. I'll put all 3 transformers in a seperate enclosure and run seperate DC feeds to all 3 devices.
Thanks for the advice.
westers151 said:
westers151,
Yes , with separate boxes you can have all combinations. I am testing right now this CD and lampucera kit mounted on separate wooden plate and yes amplification goes through gainclone
But I am pretty angry now because of SPDIF lack. Maybe I will talk about later. It is not related to this particular CD player, then more like general perception.
The main thing is that I am focusing myself to pure analog signal from CD player, and possible improving perfomance adding some kind of buffer at analog output.
Transformer verification
I've just picked up a couple of transformers for an absolute bargain price - too good to turn down even if they don't turn out to be suitable for this project.
Am I correct in assuming that a 120VA 2 x12V toroidal transformer will be fine with this project?
I know Peter used a 96VA, 2 x12VA transformer, but I figure that the extra VA capacity isn't going to do any harm, the main thing being that the secondaries are both 12V output.
Anyway, at £1.60, yes £1.60!!! (just under $3) for the transformer then it was worth the gamble.
If anyone is interested then I got it from CPC Farnell in the UK. Click on the Special Offers tab at the top, and then click Bargain Corner. Loads of stuff to be had, including components and many more transformers.
I've just picked up a couple of transformers for an absolute bargain price - too good to turn down even if they don't turn out to be suitable for this project.
Am I correct in assuming that a 120VA 2 x12V toroidal transformer will be fine with this project?
I know Peter used a 96VA, 2 x12VA transformer, but I figure that the extra VA capacity isn't going to do any harm, the main thing being that the secondaries are both 12V output.
Anyway, at £1.60, yes £1.60!!! (just under $3) for the transformer then it was worth the gamble.
If anyone is interested then I got it from CPC Farnell in the UK. Click on the Special Offers tab at the top, and then click Bargain Corner. Loads of stuff to be had, including components and many more transformers.
Re: Transformer verification
Think MGB V8 with tuned engine on nitrous oxide
(in a straight line, mind you). Overengineering OK, but this... I couldn't say if a transformer of more then 10 times the needed capacity will be beneficial (or the opposite) for the sound. For you to find out...
Peter seems to favour EI transformers for digital circuits because they suppress the pollution on the mains better than toroids.
Now that I think about it, both my high-end CD-player and DAC do not have toroids...
That's certainly a bargain! Even if you don't like them, you can still use them to add weight to the 'clone...
About the 2x 12 Vrms, that should be fine; since you're using a stabilised PSU, doesn't matter that the toroid will probably put out more than 2x 12Vrms because of the very light load (although the bigger the transfo, the smaller the difference between loaded and unloaded voltage).
westers151 said:
Think MGB V8 with tuned engine on nitrous oxide
(in a straight line, mind you). Overengineering OK, but this... I couldn't say if a transformer of more then 10 times the needed capacity will be beneficial (or the opposite) for the sound. For you to find out...Peter seems to favour EI transformers for digital circuits because they suppress the pollution on the mains better than toroids.
Now that I think about it, both my high-end CD-player and DAC do not have toroids...
That's certainly a bargain! Even if you don't like them, you can still use them to add weight to the 'clone...
About the 2x 12 Vrms, that should be fine; since you're using a stabilised PSU, doesn't matter that the toroid will probably put out more than 2x 12Vrms because of the very light load (although the bigger the transfo, the smaller the difference between loaded and unloaded voltage).
