You can try with damping materials.
Vibration Damping Materials
Again, if You have enough time, add extra trafo and PS for audio stage. It wont cost You much. Use two pairs of LM317T/337T (one pair per channel) you will get better separation. Trafo should be 15-0-15. 20VA will be enough for audio stage.
Now I just did sep. reg for the 7310 and 7220. I couldn't listen much, since I have finished it at 8pm. But it sounded quiet good. More air, much more clearer and very detailed. vocals sounded very silky and smooth.
I will listen tomorrow all day,let the new parts burn in.
this reg just temporary, because I waiting to get some better tantalums and LM317T. Later I will do the dac and the opamps.
If I find some cheap trafo I will do the whole thing separated.
I know its a must do.
Attachments
Now I just did sep. reg for the 7310 and 7220. I couldn't listen much, since I have finished it at 8pm. But it sounded quiet good. More air, much more clearer and very detailed. vocals sounded very silky and smooth.
I will listen tomorrow all day,let the new parts burn in.
this reg just temporary, because I waiting to get some better tantalums and LM317T. Later I will do the dac and the opamps.
If I find some cheap trafo I will do the whole thing separated.
I know its a must do.
Im glad you achieved an improvements. I would install LM317 close to chips to avoid wires. I did it in my CD40. Trafo You can buy for 20EURO, any kind will work. It will be better if its bigger. From the same trafo You can feed TDA1541 also.I think You need +5v, -5v and -16V. Ill check and ill tel You tomorrow. What tantalum You are using?
I modified Telefunken HS975, separate PS for audio stage, MUSE on the output (Ill try with polipropilens also). I changed almost all caps. Still sound digital, not even close to cd40. In general sound is very clear,but there is no space arround instruments. I tried to put another DAC in parallel (Telefunken use TD6720N Toshiba) it doesnt work, it must be im missing something. Also, its very hard to find some nice datasheet for TD6720N. Next will be PS for DAC. I hope that will gave me more natural sound.
Also i would like to try to use separate DAC's for each channel, just i need to do some research how to do that.
Mutting transistor are still on their place, I forgot to remove them
For audio stage in CD40 im using low ESR Vishay capacitors 220uf/63V. Im still waiting for silmic's.
Best regards
Goran
Im glad you achieved an improvements. I would install LM317 close to chips to avoid wires. I did it in my CD40. Trafo You can buy for 20EURO, any kind will work. It will be better if its bigger. From the same trafo You can feed TDA1541 also.I think You need +5v, -5v and -16V. Ill check and ill tel You tomorrow. What tantalum You are using?
I modified Telefunken HS975, separate PS for audio stage, MUSE on the output (Ill try with polipropilens also). I changed almost all caps. Still sound digital, not even close to cd40. In general sound is very clear,but there is no space arround instruments. I tried to put another DAC in parallel (Telefunken use TD6720N Toshiba) it doesnt work, it must be im missing something. Also, its very hard to find some nice datasheet for TD6720N. Next will be PS for DAC. I hope that will gave me more natural sound.
Also i would like to try to use separate DAC's for each channel, just i need to do some research how to do that.
Mutting transistor are still on their place, I forgot to remove them
For audio stage in CD40 im using low ESR Vishay capacitors 220uf/63V. Im still waiting for silmic's.
Best regards
Goran
I'm not familiar with the toshiba dac, but the sep PS must be good.
About the regs I just drop them in and it was the easiest way to do.
My friends coming over tomorrow so I needed to do something for a fast and easy improvement.
I dont wanted to take out the board again. And only had time after dinner.
The green tantalum?? I dont know the brand,could be Vishay.
I ordered some from that french store from ebay I linked. (yellow Kemet and AVX)
Best regards
Bardos
Hello Goran,
Its been a while. I have build some series reg. for the 1541 with a 3 stepped regulator taken from ECdesign.
Unfortunately I didn't got it to work properly. There was no sound only very quiet cracking noise.
After I started disconnecting -15V and -5V. Finally I got sound.
I assume it can be some ground problem. If I do connect the -15V ground to the jumper wire on the panel right at the dac, then the -15V became -12V.
Anyway I have to take the whole thing out, because the -5V miraculously not working. I tested everything 3 times before I put them in.
But the sound changed a lot with the 5V series reg connected.
Huge 3d soundstage, clearly separated instruments with very detailed sound. I have never heard cd-s playing these good.
Sound very much like a live music. I lived in San Francisco and 3-4 times a week I listened live music so I can compare what sounds good.
Last night I listened music until midnight and I can wait to listen some music today.
Goran do you have any idea what can be the problem? Should I just separate every ground even from the panel ground? Maybe I trigger somehow the muting transistor???
here is the power section and the series reg. from ECdesign.
Its been a while. I have build some series reg. for the 1541 with a 3 stepped regulator taken from ECdesign.
Unfortunately I didn't got it to work properly. There was no sound only very quiet cracking noise.
After I started disconnecting -15V and -5V. Finally I got sound.
I assume it can be some ground problem. If I do connect the -15V ground to the jumper wire on the panel right at the dac, then the -15V became -12V.
Anyway I have to take the whole thing out, because the -5V miraculously not working. I tested everything 3 times before I put them in.
But the sound changed a lot with the 5V series reg connected.
Huge 3d soundstage, clearly separated instruments with very detailed sound. I have never heard cd-s playing these good.
Sound very much like a live music. I lived in San Francisco and 3-4 times a week I listened live music so I can compare what sounds good.
Last night I listened music until midnight and I can wait to listen some music today.
Goran do you have any idea what can be the problem? Should I just separate every ground even from the panel ground? Maybe I trigger somehow the muting transistor???
here is the power section and the series reg. from ECdesign.
Attachments
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Hello Danico
Nice to hear from You again.
Sorry you have problems with DAC PS.
Looking at your circuits i have feeling that you should use different transistors, BC560 could not handle the current whats required from TDA 1541. Maybe thatway voltage drops from 15V to 12V.
Anyway, i'll tell You how i did it.
I use cheap 7915, 7905, 7805. Unsoldered the ressistors near DAC from original PS rails and there i connect the new PS. No problems in my case. In the near future ill make new PS with LM337 and LM317.
I dont know if you have separate trafo for PS for TDA1541, if not, solder wires to the secondar of the present trafo you have 17-0-17, use shotky's for rectifiing and some nice cap's for filtering (i use cheap ones 2x2200uF/35V). Then just implement the 7805, 7915, 7905, solder the outputs of regulators to resistors near dac (first you have to unsolder that end of resistors connected to the original PS) Use radiators for 7805, 7905, and 7915, in my case the are getting really hot.
If this will work (it should work) you can upgrade the PS with more expencive parts.
Here is data for TDA1541 in the case you dont have one
Best regards
Goran
Nice to hear from You again.
Sorry you have problems with DAC PS.
Looking at your circuits i have feeling that you should use different transistors, BC560 could not handle the current whats required from TDA 1541. Maybe thatway voltage drops from 15V to 12V.
Anyway, i'll tell You how i did it.
I use cheap 7915, 7905, 7805. Unsoldered the ressistors near DAC from original PS rails and there i connect the new PS. No problems in my case. In the near future ill make new PS with LM337 and LM317.
I dont know if you have separate trafo for PS for TDA1541, if not, solder wires to the secondar of the present trafo you have 17-0-17, use shotky's for rectifiing and some nice cap's for filtering (i use cheap ones 2x2200uF/35V). Then just implement the 7805, 7915, 7905, solder the outputs of regulators to resistors near dac (first you have to unsolder that end of resistors connected to the original PS) Use radiators for 7805, 7905, and 7915, in my case the are getting really hot.
If this will work (it should work) you can upgrade the PS with more expencive parts.
Here is data for TDA1541 in the case you dont have one
Best regards
Goran
I do have separate transformator. I did try the regs and they worked well. Except I needed to change the resistor after the bc550 from 1k to 680 to get the right voltage. So maybe that can cause less current to the dac.
In my case with separate transformator do I need to isolate the dac from the original ground?? I mean there is jumper that connects all ground on the top of the board.
I chose these kind of reg. cause its supposed to be very quiet.
I think I'll be fine with these setup I just need to recheck everything. I didt got 10 volts from the power supply BD680 so that the starting point.
Best regards
Bardos
In my case with separate transformator do I need to isolate the dac from the original ground?? I mean there is jumper that connects all ground on the top of the board.
I chose these kind of reg. cause its supposed to be very quiet.
I think I'll be fine with these setup I just need to recheck everything. I didt got 10 volts from the power supply BD680 so that the starting point.
Best regards
Bardos
I dont think you have to isolate DAC ground, at least i didnt. Try to implement separated trafo for logic and display, also isolate the wires wich leads to control board, i did that with alu-folly and thick wires to ground. And the most important, tweak the transport mechanism. I get huge improvement doing that.
Best regards
Goran
Best regards
Goran
I always use discrete regs. It makes such a difference running them onto the TDA. I also use large smoothing caps (at least 10,000uF) on individual oversized transformers. This helps with huge dynamics and soundstage. Make no mistake, forget 78xx.79xx and LM317,337, fully discrete very low noise regulators that are capable of high current delivery are the difference between hifi and hi end!!
Probably you are right that a discrete PS will give better results, I have never try discrete one for DAC. In this moment im using 78XX and 79XX in series.
Can you post a schematic with discrete components? I'll be very gratefull.
Best regards
Goran
The led regulator what I use, but its only useful if you build the 3 stepped reg with the capacitance multiplier.
Or better to build with the floating power supply.
Unfortunately I managed to delete all the infos I had saved from the topic. Now I have to read all over the 384 pages.)
This regs in the 1541 MK5 and MK6 its about the end of the topic.
I highly recommend to read over very useful.
Look for the floating PS and He has a good MOSFET IV out design,too.
IV-out:
http://www.diyaudio.com/forums/digi...ding-ultimate-nos-dac-using-tda1541a-358.html
http://www.diyaudio.com/forums/digi...ding-ultimate-nos-dac-using-tda1541a-354.html
I will post the schematic after I find them again.
Best regards
Bardos
Or better to build with the floating power supply.
Unfortunately I managed to delete all the infos I had saved from the topic. Now I have to read all over the 384 pages.
)This regs in the 1541 MK5 and MK6 its about the end of the topic.
I highly recommend to read over very useful.
Look for the floating PS and He has a good MOSFET IV out design,too.
IV-out:
http://www.diyaudio.com/forums/digi...ding-ultimate-nos-dac-using-tda1541a-358.html
http://www.diyaudio.com/forums/digi...ding-ultimate-nos-dac-using-tda1541a-354.html
I will post the schematic after I find them again.
Best regards
Bardos
Inside the player I use commercial low noise regs either from Fidelity Audio ¦ The home of quality products or audiocom. It is very difficult to fit larger off board regs inside most players. My favourite reg of this type is the SPower FET output device from fidelity audio. These are also more than capable of driving high load currents and can be used on the 7220 provided they are on a small heatsink. This is what I use on the transport and servo in my CD960 (CDM1 mech). Laster year I opted to go I2S out from this 960 and put the whole DAC section off board. I used the boards from Oliver on this forum. The boards incorporate I2S attenuation and DEM reclocking from the Ultimate NOS DAC thread mentioned. They also use indepandant Salas shunt regs. The output stage uses SPower regulation. This DAC is something very special indeed.
It's all DIY but sometimes where regulation is concerned, the hard work has already been done. In my case, the commercial regs have been added 1 or 2 at a time as I could afford them over the past 3 years
I am now almost at the point where no 2 supplies share the same reg which really puts the sound in a place that I could not afford to be in an off the shelf unit. These regs cannot be recommended highly enough IMHO
It's all DIY but sometimes where regulation is concerned, the hard work has already been done. In my case, the commercial regs have been added 1 or 2 at a time as I could afford them over the past 3 years
I am now almost at the point where no 2 supplies share the same reg which really puts the sound in a place that I could not afford to be in an off the shelf unit. These regs cannot be recommended highly enough IMHO
Regarding to the regs. The 3 stepped rectifier can be used with 78xx,79xx, since there is no ripple or spike in the DC voltage.
So its easy to give it a try even for the simply reg.
From ECdesigns:
"For power supply I now always use 3-stage stepped rectifiers, these greatly reduce (limit) switching noise bandwidth as these offer "soft switching". This has nothing to do with diode type (Schottky) or diode switching noise. Its the effect of switching on / off large capacitive loads like a smoothing cap.
Next I use a capacitance multiplier to reduce ripple voltage to below approx. 1mVpp using a Darlington stage.
After that, I use LC filtering (Hybrid chokes) to filter out residual noise). This un-stabilized, clean, ripple-free DC voltage is then fed to a plain 78xx / 79xx regulator. because the input voltage is a clean DC voltage, the plain regulators (with limited bandwidth) now function without problems and offer tight load regulation.
RF / HF regulation cannot be provided by the regulator and relies on local decoupling using suitable decoupling caps and / or power supply filters.
I use large capacitor values on the regulator output (470 ... 1500uF) to filter out regulator noise.
This approach no longer requires discrete (large bandwidth) regulators.
For highly critical circuits like reference voltages, masterclock and reclocker, I use additional LC filters. These take care of the noise that managed to pass the power supply."
So its easy to give it a try even for the simply reg.
From ECdesigns:
"For power supply I now always use 3-stage stepped rectifiers, these greatly reduce (limit) switching noise bandwidth as these offer "soft switching". This has nothing to do with diode type (Schottky) or diode switching noise. Its the effect of switching on / off large capacitive loads like a smoothing cap.
Next I use a capacitance multiplier to reduce ripple voltage to below approx. 1mVpp using a Darlington stage.
After that, I use LC filtering (Hybrid chokes) to filter out residual noise). This un-stabilized, clean, ripple-free DC voltage is then fed to a plain 78xx / 79xx regulator. because the input voltage is a clean DC voltage, the plain regulators (with limited bandwidth) now function without problems and offer tight load regulation.
RF / HF regulation cannot be provided by the regulator and relies on local decoupling using suitable decoupling caps and / or power supply filters.
I use large capacitor values on the regulator output (470 ... 1500uF) to filter out regulator noise.
This approach no longer requires discrete (large bandwidth) regulators.
For highly critical circuits like reference voltages, masterclock and reclocker, I use additional LC filters. These take care of the noise that managed to pass the power supply."
Indeed but there is a drawback, EC is designing everything from the ground up. He can therefore allocate the appropriate amount of space to each supply. When modifying a CD player, you are very unlikely to have space for such a PSU especially if you are multiplying that by many rails. There are also many advantages for getting the regulation right on top of the pin you are supplying. Inside my transport, I run independant SPower regulators on the SAA7210 decoder, Ram, HF amp, System Clock, Servo clock, 3 Servo rails and 2 CDM1 rails. Thats 10 regulators assigned to the transport. If you then take into consideration the DAC, thats 1 reg on the 7220 filter, 3 regs on the TDA1541, 1 reg on the DEM logic, then another 2 on the I/V output stage and a single reg to compensate to 0vd offset, thats another 8 regs. Total 18 low noise regulators. Can you fit that many of EC's type regs inside the player. In any case, I'm not convinced that EC's regulation would sound better than a good FET based commercial reg???
I love these regs and stick them everywhere! Right onto the pin legs where possible.
I love these regs and stick them everywhere! Right onto the pin legs where possible.
Hi, just something I found out: at the input of the filter, the DC connection to ground of the opamp is lost. To me this is troublesome. I suggest connecting it to ground if not used.--> advice to bypass the filter
1 pic shows the original circuit adjusted
Just my 5 pence. albert
Not sure I follow the logic here? Pin 5 on the opamp shown which is the non inverting input is at gnd. The DEEM part of the filter is effectively switched off for pretty much all recordings and therefore can be removed if required. The final stage shown as removed provides some additional filtering and a buffer to enable some difficult loads to be driven. In my experience, I've never needed the buffer stage to drive the input of my amps over std cable lengths (<1m)
As I know. Goran building his project out of the cd player case. So he will have just enough room for the PSU and series reg. If he wanna hear what the 1541 is capable better try it.
Also I sad the 3-stepped rectifier eliminate the noise before the regs. So it will improve a lot with the old 78xx.
Its only 3 diodes and 2 resistor.
Despite of him I wanna keep it in the case.
I could manage to build the whole PSU with a separate transformator and steel have some spare room.
I just put up the picture awhile ago.
I'd better get some help to my original problem, but I rather go and take it apart and hopefully I will find it.
Its true Danico, im still building my project out of case, even many times i wanted to just give up and put all in original case. Any suggestion about discrete PS is very velcomed. Im using regulators because with that aproach i cant ruin TDA 1541. For +5V i have 7812 and 7805 in series. also vor -5V 7912 and 7905. For -15V i have just 7915.
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