Article: Computer Audiophile Pocket Server C.A.P.S. v3 Zuma

[JJJ]

Chris. Nice looking audio device. I was looking at using the same case. However, don't you think it's overpowered for what it needs to do and hence your costs are too high? The Bryston BDP-1, and I admit this won't drive a USB DAC but rather feeds S/PDIF or AES/EBU, can be had for circa $1,600 from the right dealer. The BDP-2 for $2,150. (These are not MSRP.) And with these you get Bryston engineering for the LPSU (amongst other things).

[JJJ]

You will have much higher jitter from optical media

[JJJ]

I won't be using it to play any files.

 

ok

[JJJ]

I have a question for Chris relating to power supply. Do you have any concerns with the components (motherboard, USB, SATA, sound card) all sharing the same power supply (or taking their power from the motherboard)? I guess a super-pure approach would prefer separate power supply (or separate feeds from a linear power supply?). I'm looking to deploy a linear power supply in mine.

[JJJ]

Chris,

 

In the section on the SSD selected there's a picture of the SoTM SATA power noise filter and it's mentioned in the component list but though there was a lot of information on why you think the SoTM USB filter is valuable I couldn't see anything in the verbiage about why you think the SATA noise filter adds something (or takes something away). Could you say something on this? What is it that you believe it does that is not accomplished by a) the USB power clean up and b) which the DAC itself cannot achieve by virtue of whatever strategy it employs to isolate itself from upstream failings?

 

 

Something worth looking at here:

 

17-sotm-soul-of-the-music.html

[JJJ]

You may have already seen this, but Simple Design has a battery unit that can be used to separately power the USB card. It is quite a bit less expensive than the Red Wine product, although not as flexible.

 

Thanks Stumps but battery power doesn't do it for me. I will be using a top quality linear power supply for mine.

 

PS: anyone know why when I am logged in I don't see the latest posts in this thread but when I am logged out I do? It's driving me nuts.

[JJJ]

In the post above I was trying to link directly to the image on this page which shows the drop in noise from using the filter

 

SOtM SATA Noise Filter

[JJJ]

Chris, thanks for the reply. I've been working on a similar build although with a little less power. Same enclosure. A mini-ITX motherboard which can take on-board flash memory to store the OS (Intel DH61AG) and the Intel i3 3220T processor. The smaller form factor also provides a little more room in the enclosure which I need because I will fit a fully linear power supply module and toroidal transformer. As I have a Casablanca, I'm going to use the Juli@ XTE sound card (discarding the analogue section of the card). Any thoughts on this motherboard in this case?

 

(BTW I still find it weird that when I log in I don't see the latest posts on this thread. Happens with both Firefox and Safari.)

[JJJ]

One question re cases. I have the Streacom case in black and as Chris notes it is very easily marked (not permanently but a brush of a finger will leave a smudge on the surface). I would like to find a brushed aluminium case of similar build. Is the silver version of this case again an anodized finish or brushed? Other ideas?

[JJJ]

Brilliant! Thanks Chris.

 

Question: Any reason you are only doing a USB to DAC connection as opposed to a PCIe Lynx or RME type card with AES/EBU cabling to the DAC?

 

Cheers!

 

I am using a Juli@ XTe card on mine as my DAC accepts either SPDIF cox or AES/EBU. The Juli@ card outputs SPDIF over coax via its breakout cable. Bryston use the same card but have installed a proprietary PCB to take the Juli@'s DIN off-ramp directly to SPDIF and do the conversion to AES/EBU. One great advantage of this card is that you can disconnect the entire analogue section and not install it thereby not risking any pollution from the analogue circuitry. It is also possible to modify the card to upgrade the on-board regulator and power it independently of the motherboard.

[JJJ]

I have the silver case. It is same type of surface finish but durable and no issues withholding the abuse of my two children. The really nice finished anodized cases are 3x the cost. I would consider it, in hindsight.

 

Ok thanks. I would be interested to hear from people who have found a brushed aluminium case with thick (say, 10mm) faceplate. I think the Streacom case is "ok" but it would be nice to get something of higher quality.

[JJJ]

I read in this thread someone asking about how the hard drive was mounted. I think the answer is either it wasn't or possibly double back tape was used. I found that the SATA noise filter is manufactured upside down from the mounting holes on the drive. That bugs me, so I am going to try using some intermediate cables between the filter and the drive. That won't be as neat, but I can then attach the drive to the case with screws.

 

Is this really the case? I was about to purchase the filter but this seems absolutely bonkers. I don't like the idea of fitting parts with velcro and don't even like the idea of not having the filter bolted to the enclosure. Can someone please confirm the orientation of the filter versus an SSD drive?

 

Also, in my build I need to affix the digital portion of the Juli@ XTe card to the enclosure (it will attach to the mobo via flexible riser and will be wired to a female RCA plug for S/PDIF output). I was planning to do this with a couple of M3 threaded spacers bolted to the enclosure, providing a platform for affixing the card. My question is whether I should use nylon spacers or is tapped brass ok? (I will be using existing fixture holes in the card.

[JJJ]

If it is upside down I guess one could readily drill and tap the lid of the SSD so that the threaded mounting holes go all the way through and then you could screw mount the drive inverted.

[JJJ]

Could you not screw some stand-offs onto the bottom of the SSD to raise it up, then screw through the bottom of the case as (it appears) is recommended for securing a drive normally?

 

Eloise

 

I guess one could try to find a threaded spacer, male on one end, female on the other, elevate the SSD and fit the SOtM filter upside down. Seems like a lot of work. If the mounting holes on the SSD drive went all the way through (the lid of the SSD) it would be a lot less hassle. It baffles me as to why SOtM decided to design their filter in this manner.