Well, just like the infamous EL cap, resistors do make a big difference.
For instance I am using shinkoh for cart loading in my phonos and did not find any suitable replacement. Kiwames sound really good there but lack that "fantasmagoric" kind of large sounstage the tantals can provide... RY55 are also good... IMO similar to Takman. I also tryed other types of tantal resistors like the audio note and nothing compares to shinkoh. Big shinkohs sound worst than the small ones.... some said these are made with LSD.
Due to the NOS and high price of these, I am now looking to Vishay bulk film... One friend ho is an experinenced voycing expert recently told me these are even more neutral than the tantals.
Of course there are places in the circuit that benefit more from certain characteristics than the others so I believe there is no perfect overall solution.
In my über CD53 I am using holco and RY55 in some selected places (as per Brent´s indications) and find those excelent.
For instance I am using shinkoh for cart loading in my phonos and did not find any suitable replacement. Kiwames sound really good there but lack that "fantasmagoric" kind of large sounstage the tantals can provide... RY55 are also good... IMO similar to Takman. I also tryed other types of tantal resistors like the audio note and nothing compares to shinkoh. Big shinkohs sound worst than the small ones.... some said these are made with LSD.
Due to the NOS and high price of these, I am now looking to Vishay bulk film... One friend ho is an experinenced voycing expert recently told me these are even more neutral than the tantals.
Of course there are places in the circuit that benefit more from certain characteristics than the others so I believe there is no perfect overall solution.
In my über CD53 I am using holco and RY55 in some selected places (as per Brent´s indications) and find those excelent.
DOS with CFP
Hello,
Pictured here is the new DOS module that I recently built. This incorporates the CFP circuit, and some other new features. I’ve been using the CFP circuit in my DOS for several months, but only recently have I been able to make a proper board for this design. You can read my other post for information about the board, as I have some that are available.
Ray has a very good write up on the CFP on the DOS page on his website. The real advantage of this circuit is that it stabilizes the large 1.4v voltage swings through the LTP. The large voltage swings lead to signal compression. With the CFP the compression virtually disappears and the sound really expands into the room. I noticed this immediately in the very first seconds of my first implementation of the CFP several months ago.
The module pictured below has all my favorite components in it. Rel RTE filter caps, Texas Components TX2352 resistors in the filter, Takman resistors elsewhere, Dexa low noise regulators, plus the standard BG caps.
My board is designed to accommodate these components, but can also accommodate other filter and rail caps.
I think the CFP is a nice addition to the original DOS, and well worth the effort to incorporate this modification into the circuit. Ray will soon have one of these made up and going in his 8400 player. It will be interesting to read his comments, assuming he will have some, when that all happens.
Just thought I would share this with everyone.
Steve
Hello,
Pictured here is the new DOS module that I recently built. This incorporates the CFP circuit, and some other new features. I’ve been using the CFP circuit in my DOS for several months, but only recently have I been able to make a proper board for this design. You can read my other post for information about the board, as I have some that are available.
Ray has a very good write up on the CFP on the DOS page on his website. The real advantage of this circuit is that it stabilizes the large 1.4v voltage swings through the LTP. The large voltage swings lead to signal compression. With the CFP the compression virtually disappears and the sound really expands into the room. I noticed this immediately in the very first seconds of my first implementation of the CFP several months ago.
The module pictured below has all my favorite components in it. Rel RTE filter caps, Texas Components TX2352 resistors in the filter, Takman resistors elsewhere, Dexa low noise regulators, plus the standard BG caps.
My board is designed to accommodate these components, but can also accommodate other filter and rail caps.
I think the CFP is a nice addition to the original DOS, and well worth the effort to incorporate this modification into the circuit. Ray will soon have one of these made up and going in his 8400 player. It will be interesting to read his comments, assuming he will have some, when that all happens.
Just thought I would share this with everyone.
Steve
New Dos Board
Hello
I have made a new board for the DOS. This board, pictured below, incorporates the CFP circuit that I came upon several months ago. You can read about the CFP on Ray’s website.
Features of this board are as follows:
This is a 2 layer board. Top layer is a ground plane and all circuit tracks are on the bottom layer.
Passive low pass filter is same as in original DOS circuit. I have sized the filter caps for the Rel RTE polystyrenes, and have added additional pads to accommodate the LCR polystyrenes and other caps of similar spacing.
In the differential section there is the addition of transistors and resistors that make up the CFP addition to the LTP. All resistor footprints are large enough to accommodate most any size resistor with horizontal mounting.
In the buffer I have added a current sink, replacing the 1.8k resistor. This is an addition of another 2SK170BL and a couple of resistors.
I have also added a bypass cap to the rail cap in each power rail.
The board has 4 power rails. If you wish to use only 2 rails, you just use wire links under the board.
I have added additional pads to the rail cap footprints to accommodate smaller spaced, 2.5mm, caps.
The mounting holes are M3.
The board size is a little bit larger than Ray’s original DOS board, but should still easily fit in your player.
I have several boards available to interested persons wanting to make this new DOS circuit.
You can PM me here, if interested.
Steve
Hello
I have made a new board for the DOS. This board, pictured below, incorporates the CFP circuit that I came upon several months ago. You can read about the CFP on Ray’s website.
Features of this board are as follows:
This is a 2 layer board. Top layer is a ground plane and all circuit tracks are on the bottom layer.
Passive low pass filter is same as in original DOS circuit. I have sized the filter caps for the Rel RTE polystyrenes, and have added additional pads to accommodate the LCR polystyrenes and other caps of similar spacing.
In the differential section there is the addition of transistors and resistors that make up the CFP addition to the LTP. All resistor footprints are large enough to accommodate most any size resistor with horizontal mounting.
In the buffer I have added a current sink, replacing the 1.8k resistor. This is an addition of another 2SK170BL and a couple of resistors.
I have also added a bypass cap to the rail cap in each power rail.
The board has 4 power rails. If you wish to use only 2 rails, you just use wire links under the board.
I have added additional pads to the rail cap footprints to accommodate smaller spaced, 2.5mm, caps.
The mounting holes are M3.
The board size is a little bit larger than Ray’s original DOS board, but should still easily fit in your player.
I have several boards available to interested persons wanting to make this new DOS circuit.
You can PM me here, if interested.
Steve
Dumb question
is this in addition to the DOS board, or an aternative? Another step to heaven or a side-step? I have Ray's latest version of the DOS installed and of course I have the itch...following doggedly in other's footsteps, to go where no Marantz has gone before..Ray?
is this in addition to the DOS board, or an aternative? Another step to heaven or a side-step? I have Ray's latest version of the DOS installed and of course I have the itch...following doggedly in other's footsteps, to go where no Marantz has gone before..Ray?
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Hi Shep,
It's a bit of both actually. It's a further development of the DOS-circuit: the differential input stage is made more linear by adding two extra transistors. The results of this is less distortion and of course that leads to.... Better Sound! You can check out the circuit on my DOS-CPF page (still under construction).
So if you want to upgrade your current DOS you can add the extra components on the underside of the board, or do some other nifty mod of course. Or you could get one of those excellent new boards from Steve (i'm not a stock-holder of Steve Inc. by the way) and build it all new, and maybe even do some additional component-upgrades while you are there!
So i'd say it's another step closer to heaven
Regards,
Ray
It's a bit of both actually
. It's a further development of the DOS-circuit: the differential input stage is made more linear by adding two extra transistors. The results of this is less distortion and of course that leads to.... Better Sound! You can check out the circuit on my DOS-CPF page (still under construction).So if you want to upgrade your current DOS you can add the extra components on the underside of the board, or do some other nifty mod of course. Or you could get one of those excellent new boards from Steve (i'm not a stock-holder of Steve Inc. by the way
) and build it all new, and maybe even do some additional component-upgrades while you are there!So i'd say it's another step closer to heaven
Regards,
Ray
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Pcb looks very good. I'll get myself one of these and swap all the nice bits off my dos onto the pcb. Might do it at the same time as building an external psu for the dos. What cost are we looking at for these?
Brent
"In the buffer I have added a current sink, replacing the 1.8k resistor. This is an addition of another 2SK170BL and a couple of resistors."
I do not see this current sink in Ray´s schematic.... can you please elucidate ?
I do not believe this board can fit inside my CDP.... can I mod the existing DOS ?
I do not see this current sink in Ray´s schematic.... can you please elucidate ?
I do not believe this board can fit inside my CDP.... can I mod the existing DOS ?
Everything you need is on Ray's website. If you can't add a bigger board for space reasons you can add the CFP parts under the old DOS board. This is not as neat, but it will work. It's what I used for a few months. Forget the current sink, you need the new board for that. It's just a small extra that was suggested and added. The CFP is what makes the difference.