MicroSD Memory Card Transport Project

Would be nice to have detail for the external clock multiplier and comparator circuit and which are the modification at the transport in order to accept the external clock?

I will ask Mr. Ishida whether he can disclose his circuit or not.
Regarding his modification, I heard that he removed a resister at an output of TCXO and extended wires to his sub board.

Bunpei
 
Mini Review by SR

SR, One of our users in Europe, gave me his mini review report with his permission to post it here by his private e-mail.
Bunpei

Mini Review by SR, February 2010
Conclusion
----------
The SDTrans192 player won me over for its superb sonics and extraordinary high rez capabilities. It is so darn good that the $450 price tag is fully justified.
Build quality and functionality are outstanding, operation is flawles, and service is very good.

Compared to the $115 memory card player QA550 from QLS Hifi Audio,
the SDTrans192 beats it hands down. And that is using SPDIF from the SDTrans192 and I2S output from the QA-550.
 
Mini Review by SR (Detailed Test Description)

SR, One of our users in Europe, gave me his mini review report with his permission to post it here by his private e-mail.

Mini Review by SR, February 2010
Detailed Test Description
------------------------

The Japanese guys Bunpei and Chiaki have been working on their memory card player since April 2009. Going from prototype version 1.0 to the now available version 2.1 which is a totally other beast than the more simple version 1.0.

Sidebar: do have a look at Chiakis immaculate wiring on his prototype board here http://www.diyaudio.com/forums/digi...ory-card-transport-project-3.html#post1883508

Version 2.1, which I have tested the last week, can play WAV files up to 24/352.8 kHz. Not many players - not even commercial ones - can boast with being able to play these DXD files. An amazing achievement! I had no isses playing and listening to files up to 24/192 - I cannot listen to DXD files.

The player can be used with SD cards in sizes 2 - 32 GB (FAT and FAT32)
and I had no issues what so ever with my mix of different SD and SD/HC cards in
sizes 2, 4, 8, 16, and 32 GB from a variety of manufacturers. They all worked fine.

The player can interface to DACs via transformer-coupled SPDIF or via I2S.
There is also the possibility to
hook up an I2C interface, but I did not test I2C, nor did I use the I2S interface. I plan to test the I2S interface later on, and compare sonics against the external HiFace USB->SPDIF converter which can convert up to 24/192.

They call it a kit but what it actually takes to get it playing is
a 5V power supply. Then you are ready for music.

The 16-char X 2-lines display deserves some extra words. It is gorgeous! So bright and so sharp. A medium blue background with white letters. A small pot lets you can change the brightness level. The display shows what song nr is being played, what bit depth and sampling frequency the WAV file has, and a blinking arrow shows that the player is playing music.

Five green LEDs let you know that all the different power supplies on the board are fully operational. Two other LEDs show if the SD card is accessed and if the I2S output buffer is empty.

Four soft buttons control the player. I really like the feel of these buttons.
There are the standard play, rew, and fwd
buttons, and a fourth mode button lets you change music files folder.

For this review, I used a linear 5V power supply and my own SPDIF 75 Ohm cable with Furutech rhodiumised BNC and RCA connectors. The DAC that I used was the PCM1792A evaluation board. This board has been totally modifed on the analog side with TX2352 resistors and polyprop film caps for decoupling and filtering. IV conversion on the eval board is made with
LT1468 OPamps. The eval board is powered from four linear regulated power supplies.

I used the HD650 headphones throughout the test. My own discrete dual mono headphone amplifiers fed the head phones.

The 4 GB SD card that comes with the SDTrans192 is packed with high rez music
- all the up to DXD resolutions - from 2L. A neat feature of the kit. For my sonical evaluation, however, I used my own music with whom I am familiarised.

Listening to my well-known, EAC-ripped music, this player can really "sing"!
Bass is firm and detailed down to the lowest octave, mids are natural, and the treble is silky smooth. Resolution is top notch. Soundstage is very wide.

Comparing the SDTrans192 (via SPDIF) to a car battery-powered QA-550 (via I2S) and having each player use a 2 GB sound card with the exact same WAV files, I can, on for ex "Tiden bara gaar" (OPUS3 Records), hear that the triangle really sounds like a triangle, and the congo drums are more sculptured out than on the QA-550, and the bass line is easier to follow on the SDTrans192.

Now, the QA-550 has been my main digital source the last year. For $115 it is bargain! Still, its treble representation is not on par with the one from the SDTrans192. That I can hear on for ex Dire Strait's "Love Over Gold" song where both the hi-hat and the reverberation of the snare drum are more silky smooth on the SDTrans192. On the QA-550 these sounds are almost harsh.

On Sly Stone's reggae-influenced song "Moanin'" (Telarc) the sound opens up with the SDTrans192. It becomes wider. The reverb tones from the SDTrans are a bit more easy to hear, and in general, sonics are "cleaner" with less harshness with the SDTrans192.

Female voices get a more present and full presentation on the SDTrans192 which I hear on "Black crow". The drums on "Drummer's reel" are faster with less ringing on the SDTRans192. Transients are not harder but less smeared out.

Like the QA-550, the SDTrans192 makes my feet tap to the music :)

The SDTrans192 player is now my main digital source.

What could one more wish for in the SDTrans192?
Well, I for one would like to be able to see on the
display what song is being played. I have forwared this request to the designers, and let's hope that they will implement it.
 
Yesterday, at elecon's site at Tokyo, I listened Mr. Ishida's SDTrans192 with Rubidium-based external clocking units.
The effect was especially and easily detectable on 352.8 kHz / 24 bit 2L DXD sources. I think its sound is the most perfect and accurate among digital sounds that I ever listened though my experiences are limited.
I felt every single tone was maintained as non-degradated. I was astonished that even a faint diminishing sound of strings and piano held its fine structures.

Mr. Ishida prepared his clocking systems after his vigorous efforts.
However, costs for materials are not so expensive at all.

He selected Rubidium Oscillator FE-5680A that was easily available at eBay.
1 Hz to 20 MHz|Programable Rubidium Frequency standard - eBay (item 290301888238 end time Feb-03-10 05:56:05 PST)
As SDTrans192 requires two master clocks, 22.5792 MHz & 24.576 MHz, he prepared two units.
125784346038816219293_2clock.jpg

(If you send appropriate commands to the unit by way of a serial control line, you can change its output frequency easily. This time, he prepares two units of pre-set.)
FE-5680A's frequency limit is 20 MHz and its output wave shape is sine-only. Mr. Ishida made a multiplier with sine->square shaping using Phase Link PLL502-02 and a comparator.
http://www.phaselink.com/pdffiles/PLL502-02.PDF
Therefore, two FE-5680A were set for 11.2896 MHz and 12.288 MHz, respectively.
The multiplier & comparator unit is shown on a sub-board appearing to the right side of SDTrans192. He also tweaked SDTrans192 clocking circuits in order to accept external clocks.
126432338988116201349_SDTrans192-3.jpg


I'd like to express my gratitude to Mr. Ishida and "elecon" who offered his excellent audio room and equipment for listening tests.

can i know how to make the clock into square wave, and the design of the circuit where the 11.2896mhz clock enters the clock multiplier IC?
i read after the ic specsheet, it says only accept 12mhz and above up to 50mhz?
 
Would be nice to have detail for the external clock multiplier and comparator circuit and which are the modification at the transport in order to accept the external clock?

can i know how to make the clock into square wave, and the design of the circuit where the 11.2896mhz clock enters the clock multiplier IC?
i read after the ic specsheet, it says only accept 12mhz and above up to 50mhz?

Mr. Ishida sent me his schematic and asked me posting here.
He hopes it is helpful.
 

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I have joined this thread recently. I would like to purchase the kit, can someone help with the necessary link.

Dear Luke,

I sent detailed information to you by my private message.
Please read it and give me a private usual e-mail reply if you are interested in this kit.
You can look at some pictures on Chiaki's web site also
SDƒJ�[ƒh�Eƒgƒ‰ƒ“ƒXƒ|�[ƒg‚ð�ì‚Á‚Ä‚Ý‚Ü‚µ‚½�@�|‚»‚Ì2�|�@SDTrans192
though the page is written in Japanese.

Best regards,
Bunpei