[strohmie]

...stupid double post. I refresh the DIY forum and my previous reply didn't appear, and now I post a similar one and miraculously the original has been posted.

 

[was ist los?]

I will be ordering my drive in June after funds come in. I look forward to your experience. I really wish BrianGT would finish his boards soon.
Another alternative is have jefemeister design us the control modules and boards.

BTW, i'm curious why you chose the TDA1541 over the TDA1543.

 

[Kenny12]

are there any good sacd transports?

 

[jefemeister]

Quote:

Originally Posted by strohmie The reason behind using I2S is the much reduced jitter in its output as compared to spdif, if I hadn't mentioned that previously.

I was not completely accurate earlier when I desribed I2S and 1704 interfaces. It turns out that I2S interface closely matches the 1704 interface it's just not called I2S. I haven't loked into the timing too deeply, but I believe they can be made compatible if the I2S from the transport is the proper justification and endianess. Here's the bus spec from Philips.

Quote:

Originally Posted by was ist los? Another alternative is have jefemeister design us the control modules and boards.

How well do you pay?

I'm more than willing to help out but obviously can't go that far.

 

[strohmie]

Another quick update -- I finally heard back from Nico Theveissen of the daisy-laser.nl website who sells the CD-Pro2M packages. Apparently my e-mail got eaten by a spam blocker. Anywho, now I have to decide whether I want to cancel my Enco order (if it hasn't already been processed) and buy the more complete package to avoid the control module crap.

So if anyone orders from Nico, beware that it might take a while for him to get back to you.

 

[taoster]

this is diyish REDGUM RGCD2

REDGUM DAC/CD Player, the world’s first user-serviceable CD Player versatile as a CD player or DAC is designed and made in Australia using Burr Brown components. REDGUM Audio has produced the world’s first Digital-Analogue Convertor that has the versatility of enhancing an existing system or being upgraded to a CD Player. This is a unique product in Hi-Fi. When the most usual repair problem arises (laser assembly malfunction), customers can immediately remedy it themselves without needing any expertise or paying labour costs. To meet every customers needs, the REDGUM unit can be purchased as a stand-alone DAC, or with an optional CD Rom Drive. Customers pay only for what they want to use now, with the benefit of all future options. The most frequent point of failure in a hi-fi system these days is the CD player. The most frequent point of failure in the CD is the laser assembly. Who is not familar now with the solution that “it is cheaper to get a new one”? If the customer is satisfied with the sound quality of a cheap replacement CD player when the laser “dies”, then honour is satisfied. However, Hi-Fi enthusiasts demand more of their hand-picked product, usually chosen at great expense. They rightly expect a longer life for such a price. REDGUM has a solution to short-lived CD players- discard only what needs to be discarded, keep what is of value. In a REDGUM DAC/CD the electronics are valuable. The Rolls Royce of DA chips - Burr-Brown Integrated Circuits - are used. Combined with this is the high standard of the DAC design by Jon De Sensi of Music Labs fame. As to what should be discarded, Ian Robinson’s logic was simple. If the customer could simply replace the faulty part when necessary, the sound quality of the system could be maintained using a CD Rom Drive in the place of a conventional CD laser assembly. By undoing only a few screws, the customer could immediately “repair” a faulty laser, or upgrade to a preferred drive. No labour costs - just the the continued enjoyment of high quality sonics.

The digital bit stream (zeros and ones) is fed straight off the laser (the only use of the electronics in the CD-ROM unit) into a Cyrus Logic CS8412 "8 X over-sampling Digital Jitter correction chip which is fed from its own crystal timing clock. This in turn, is fed into another Cyrus Logic digital splitter for left-right channel separation and jitter correction, and the signal then goes to the highly credentialled Burr-Brown PCM1710U Dual 20-bit DAC. Jon De-Sensi of MusicLabs, Melbourne, designed the Digital Analogue Converter circuitry. The final output stage, designed by Redgum Audio, is driven by an AD712J Dual Precision, high speed, BiFET OP Amp.

 

[was ist los?]

strohmie, any report on progress? Where did you end up getting your drive? Have you heard from BrianGT?

 

[strohmie]

Quote:

Originally Posted by was ist los? strohmie, any report on progress? Where did you end up getting your drive? Have you heard from BrianGT?

Momentarily I'm waiting to hear back from Nico Thevissen -- I bought a drive from Enco, but decided to return it so that I could get the control board Nico sells rather than trying to get in touch with BrianGT. Unfortunately Nico is out of town until the 2nd, so I won't hear back from him for a few days.

Meanwhile, I'm going to start researching DACs first while I wait for the transport parts. There's one designer at diyaudio who has a TDA1541 board he's creating that accepts I2S as its input, so I'm ordering a board from him when they come available. Given that I'll have that board for a non-oversampling DAC, I'm going to look into PCM1704 or possibly PCM1794 designs for the oversampling approach. I'll post more this week when I have the chance to do more research (relaxing and pigging out on Mem. Day vacation currently).

 

[was ist los?]

Well i too have decided on the TDA1541. I want a tube output stage. I have an AD1865 on hand, but don't know whether or not to use it. Decisions decisions.
I think i'll try to contact BrianGT about his boards.

 

[was ist los?]

Well i contacted BrianGT and got a response a few days ago about the boards. He says he's busy and when he gets the boards done, he'll post at diyaudio.com

 

[strohmie]

Finally an update.

After much trouble I was finally able to order a standard package from Nico which included the control module and CD-Pro2M. I was able to have the package sent by registered mail instead of international UPS only because I am a student, so hopefully I saved myself about $50 in shipping and possibly up to $100 in customs fees. All the same it cost about $445 plus a $32 wire transfer fee.

Nico's a great guy, and I don't want to take away business from him, but I have to recommend that anyone who tries one of these projects in the future to go with a module from Enco Systems and wait until BrianGT makes his control module available (or perhaps a CDM12 from Steinmusic which includes a control package, I think). I'll report back when the package actually gets to me (one-two weeks since it's being sent by registered mail).

Time to start thinking about the DAC and power supplies again. A good fellow named Pedja at diyaudio is building a pretty comprehensive TDA1541 DAC board with I2S input, and is supposed to have those ready to go within the next few weeks. For now I'm going to hold off on designing a PCM1704 or perhaps PCM1794 DAC and instead am going to start thinking about the power supply for the Pro2M module. I'm pretty sure it requires multiple voltage levels but I'll have to check the exact values. So much money to waste.

 

[was ist los?]

I will be going the CDM-12.1 route since i'm on a limited budget. The CDM-12s are the same as the CD-Pros except the CDMs are plastic and have a tray mechanism. I will be ordering my CDM soon. Another plus is it's half the price with shipping included and has a built in PSU, however, i will upgrade mine in the future.

 

[strohmie]

Above is the whole set. We've got the CDPro2M module on left, the control module in the center (I'm not opening it until I have everything ready because it is very sensitive to shock), the remote at the top, and various accessories to the right (display stuff, interconnects, etc.).

Time to get cracking on the power supplies and DACs. Will probably post a few things later tonight.

 

[Gman]

Quote:

Originally Posted by strohmie Ah good, another victim. Where aer you buying the CDM12 from? I just sent an e-mail out to try to purchase the CD-Pro2M but I might also buy a CDM12 for comparison's sake.

MCM electronics has a Philips 12.1 for sale in their summer savings catalog for $26.00.

G

 

[strohmie]

Quote:

Originally Posted by Gman MCM electronics has a Philips 12.1 for sale in their summer savings catalog for $26.00.

Interesting...might have to snatch that up. Is that listed online anywhere? If not I get to hunt down the print version.