Buffalo II

[BrianDonegan]

Originally Posted by glt

Russ/Brian,

Q1: How is the analog reg daughter board attached? with headers and pins?

Yes

Q2: Don't you need some bypass caps at the inputs of the analog reg daughter board?

Yes. Done.

[glt]

Thanks. BTW, I did a cost comparison between Buff II and Buff I (24bit) and Buff II is actually a better bang-for-buck deal.

[BrianDonegan]

Originally Posted by glt

Thanks. BTW, I did a cost comparison between Buff II and Buff I (24bit) and Buff II is actually a better bang-for-buck deal.

That was one of our goals. I assume your analysis does not include the two-dozen components on the bottom of the board .

[Russ White]

Yes not all the components are shown in the pictures.

glt, if you are referring to the filter caps that were at the differential input of the old IVY, those are not required (or in any way desirable) in the new design.

The IVY-III has a lot of differences from the first generation IVY.

The power supply rails are both well decoupled and well bypassed.

Cheers!
Russ

[glt]

Originally Posted by Russ White

Yes not all the components are shown in the pictures.

glt, if you are referring to the filter caps that were at the differential input of the old IVY, those are not required (or in any way desirable) in the new design.

The IVY-III has a lot of differences from the first generation IVY.

The power supply rails are both well decoupled and well bypassed.

Cheers!
Russ

Yeah, not including the components on the back of the board.
I was referring to bypass caps (100uf) at the Vin for the analog regulator daughter board. [You can see the cost comparison in the blog]

I have not looked at the new IVY in any detail (not much to look at yet :-))

Q: Are there plans of making a single version of the analog regulator daughter board so one can just plug it into the 3 pins of the clock supply :-)?

[Russ White]

Ahh yes that AVCC is well bypassed too. No worries there. Remember too that it is pre-regulated and presents a constant current load..

Yes there are plans for a single version of that reg. I actually almost have it done.

But, if you ever take apart one of those clocks(it is a pcb with a circuit of its own), you will see why the regulator we use is actually quite well suited.

Cheers!
Russ

[BrianDonegan]

Nice comparison.

I want to point out that the XO on the production Buffalos are actually custom built 20ppm units (when you order a lot of them... )

We are also now sold out of this batch, despite having a lot of them made.

We will begin mustering to get another batch going soon. It's amazing how low part inventories are right now.

[orpheus]

I posted on the digital board and didn't get a response, so I thought I'd post here.

I've ordered a Buffalo II and am planning the digital input scheme. I am thinking of connecting the SPDIF in and ground to a BNC, and then the 3 I2S/DSD inputs and the same ground to either a 4 pin XLR, RJ45, Lemo, or 2 more BNC's.

Would any particular connector work better? I have read that DSD should use CAT5, and some manufacturers are using CAT5 for I2S, so are RJ45's the best connectors?

Would it be a problem to connect the digital input ground to a BNC for the SPDIF and also to another connector for I2S/DSD? Should this ground also go to chassis ground at the connector?

Also, are there any problems with running I2S or DSD on a short CAT5 cable? I was thinking of modding one of my SACD players to output DSD, and I'm still thinking about the transport for an I2S connection.

Thank you for taking the time to read my post. I searched, but couldn't find a good answer, so if anyone happens to know what is ideal for these digital connections, I would appreciate the help.

Best,
Aaron.

[Bunpei]

Originally Posted by orpheus

I am thinking of connecting the SPDIF in and ground to a BNC, and then the 3 I2S/DSD inputs and the same ground to either a 4 pin XLR, RJ45, Lemo, or 2 more BNC's.

Would any particular connector work better? I have read that DSD should use CAT5, and some manufacturers are using CAT5 for I2S, so are RJ45's the best connectors?

Chiaki and I have connected I2S signals of up to 352.8 kHz / 24 bit or 192 kHz / 32 bit from our DIY transport to ESS ES9018 2 CH Evaluation Board.
In our case, we use a flat cable that is usually used in digital circuits and its length is less than 5 inches. We have not experienced co-existence of S/PDIF and I2S. When we try I2S, we remove a S/PDIF line and vice versa.
As you may know, usual I2S is not a differential but a single-ended digital signal. Therefore, I do not believe a combination of CAT5 cable and RJ45 plug/jack is suitable. They are for a differential transmission.
Anyway, I think we should select appropriate one by observing waveform with an oscilloscope and listening actual sounds. Sometimes, we may need a trimmed termination resister for a line.
My friend uses a 6P DIN connector for I2S signals(including MCLK).

Bunpei

[glt]

Originally Posted by orpheus

I posted on the digital board and didn't get a response, so I thought I'd post here.


Would any particular connector work better? I have read that DSD should use CAT5, and some manufacturers are using CAT5 for I2S, so are RJ45's the best connectors?

Also, are there any problems with running I2S or DSD on a short CAT5 cable? I was thinking of modding one of my SACD players to output DSD, and I'm still thinking about the transport for an I2S connection.


Best,
Aaron.

I'll say that for short runs, any cable will work. Cat 5 is actually very good copper and they come in twisted pairs that provides shielding (if you want more shielding, you can get cat-6). You can connect all the "white" wires to gnd.

If you look at the RJ45 connectors, it is basically two wires touching each other, except that if you use the Ethernet-ready sockets, they have a little pcb with some funny looking trace patterns which I think is for high speed issues (reflection and so forth) which I'm not sure matters or not in audio.