Help me select an Audio PC

[sgr]

Hi,

I could sure need some help buying or building an Audio PC. Thanks in advance.

 

Choice 1. Small Green Computer's Micro Zuma

 

C.A.P.S. v3 micro Zuma

The C.A.P.S v3 (Computer Audiophile Pocket Server) was designed by Computer Audiophile author and computer audio expert Chris Connaker to be the ultimate small, noiseless, Windows-based music server.

 

Chris talks about the C.A.P.S v3 design in his blog:

 

Computer Audiophile - Computer Audiophile Pocket Server C.A.P.S. v3 Zuma

 

The latest in the CAPS line, the micro ZUMA fits all of the functionality of the ZUMA in 1/3 of the size.

 

Our C.A.P.S v3 micro Zuma build includes:

 

Fanless design

Noiseless, no extra sound in your listening room

SOtM tX-USBexp precision oscillator USB card

Windows 8.1 Pro 64-bit

8 or 16 GB memory (select memory configuration below)

Intel i7 processor (Haswell) for high CPU usage playback such as up-sampling or room correction

SAMSUNG mSATA card for fast silent disk access

Auto-switching power 110v/220v supply. Works in any country.

Small size (3" H x 11.25" W x 9.25" D)

Firewire Option - If you have a Firewire DAC this option adds 2x 1394B firewire ports + 1x 1394A firewire port to the back of the CAPS. The card we use has a TI chipset which is considered the best for audio application. With both Firewire port types you can connect any Firewire DAC with this option. The Firewire card replaces the SOtM card.

 

Linear Power Supply - If you order this supply with the CAPS I will add an Aerospace GX16 connector to the CAPS case. This will provide a twist lock connection for the power supply cable on both ends.

 

NOTE: If you choose not to purchase the SOtM card I will include a 12v internal power connector so you can power another type of card.

 

 

 

Choice 2 from EndPc Noises

Absolutely Noiseless System

I7 4790

16gb RAM

Specs are at this site.

 

Streacom FC10 Fanless PC | Streacom Heatpipe Computer

 

Choice 3 use a recipe from this site based on Streacom FCB 10 case, linear PSU,

Don't know which motherboard.

[firedog]

Well, in audio terms, it's 3 PC choices that are essentially the same. The original Zuma is already an "old" design, so it has only a 3rd generation Intel setup today you want at least a 4th generation one. Although I doubt that would make much difference in the sound itself. In non audio aspects, depends a little bit on exactly which features you want your audio PC to have. Different MBs and cases give you slightly different choices. And of course your choice of the SOtM card or FW card. And whether you want the linear power supply or some other PS. Also price and looks may come into play.

 

If these are your 3 choices, I don't think the actual PC itself will make much difference in the SQ, once you've made those choices.

 

Of course, if you aren't in a hurry you might want to wait on Chris' upcoming CAPS 4. Intel is starting to sell new I5 and I7 motherboards and CPU's that are very low in power demands and don't need fans at all to stay cool. So there will be lots of off the shelf fanless quiet PCs and laptops available soon. I'm guessing that at least some of the new CAPS will be of this type of motherboard and CPU.

[sgr]

Good idea. Thanks. I think for now I'll just pursue an ATX linear PSU for my current pc.

Then see what Chrs's new specs will be.

[Jabs1542]

Not sure about the CAPSv4 but Chris did a good job with the first 3 being different systems with different purposes. I went the Micro Zuma route with SOtM card and have been pleased. As for Small Green Computer, their price for the computer was about what I could get all the parts for - which means I would then have to build / relearn PC hardware - no thank you.

 

My CAPSv3 runs at about 100 degrees F in a room that is usually around 72 degrees. I run CoreTemp to monitor the CPU temperature. The machine basically idles while playing JRMC, the only time it gets really warm is when I run ISO2DSD on several disks at once. I chose this machine due to its additional horsepower (I7, 16 GB, etc) to perform quasi DAW functions (ripping vinyl, SACD conversion, etc.). Now I am running HQPlayer on the Zuma and once again, it has the muscle to up convert Redbook to DSD using some fairly complex filters - CoreTemp is 130 degrees.

 

In the vane of "what type of music do you like to listen to" response you give when someone asks you about an audio recommendation. You should consider "what processing functions do I want this computer to make?" before you finalize your decision. BTW - if you want a simple machine to do nothing but serve music (i.e. JRMC) I would recommend a lower priced version (< $1,000) and get a good interface card and power supply.

[EuroDriver]

Intel is starting to sell new I5 and I7 motherboards and CPU's that are very low in power demands and don't need fans at all to stay cool. So there will be lots of off the shelf fanless quiet PCs and laptops available soon. I'm guessing that at least some of the new CAPS will be of this type of motherboard and CPU.

 

Sadly, Intel is getting out of the motherboard business and not even providing BIOS updates for 87 chipset boards to handle Haswell refresh processors. The latest Intel MoBo chipset Z97 is built in a large number of 3rd party MOBO's but no Intel board is offered.

 

Check on the Intel website that the MoBo you are planning to use is actually compatible with the processor you are planning to use. I have seen two non Intel sites making incorrect statements about Intel MoBo compatibility

 

check this thread for more details

http://www.computeraudiophile.com/f10-music-servers/completely-stumped-21911/

[Hifidelit]

Good advice from EuroDriver - checking compatibility and availabilty of CPUs is almost becoming a full time job.

 

The Intel decision not to update the bios for the Haswell refresh I was hoping for is poor support, but the 4770T is a good choice and is what I had been supplying but I've had to change from that now too (to the 4770S) as it's getting to be a pain to get hold of it from decent suppliers in the UK.

[One and a half]

For the last two years or so, the prime music server at home is the Mac Mini Windows 7 and Jriver. 1st iteration was the i5 with 16GB ram and spinning drive, music files were either on a portable Drive or NAS. The music was fine for redbook, but not 100% operability. On DSD the i5 would struggle and occasionally break up the stream especially when using jriver's DSD128 transcoding.

 

 

Fast Forward to the start of this year with an i7 Mac Mini hybrid SSD and 1.5TB internal drive. DSD playback doesn't struggle anymore, however every now and again, the same little jagged edges of transmission error or breakup, not all the time, but audible none the less. Portable FW drives were used leaving USB free for the DAC. This Mac Mini has USB3 ports. Had I not had a lot of drama with a Grace m903 using USB3, I would not have noticed this, but thought OK, maybe USB3 is causing problems, creating the jagged responses now and again. USB2 is no problem for the m903.

 

 

The other Mac Mini running Mavericks is used solely for file storage and management for about 12 months. This includes downloading music from vendors such as Qobuz, Acoustic Sounds, HiresAudio. From this computer, files are transferred to the music server & portable drives.

I'm not that familiar with OSX like others on this forum, but I did give it a fair amount of attention and it works fine. Problems occur with a mixed environment of OSX saving to NTFS and the other way round, and copying large (DSD) files about the place is really tedious on a network to portable drives.

 

 

I could consolidate all the portable FW drives into the one machine (3TB x 4) and if necessary the Mac Mini could be used as a music server. I have a NAS and it's mothballed. Enter a $1300 HP Z800 Workstation (2009) with twin Xeon 2GHz, 24GB RAM, Quadro 5800 refurbished, which was set up over the weekend with Win7 Pro. Curious as to how this computer would play audio as it has "just" USB2 ports and due to its nature should be noisy as all. Suits the experiment for the USB2 though.

 

 

The sound playing from the Workstation delivered with no jagged edges, drop outs, fluffs, gaffs, just the glorious music. Let it play most of the weekend, and it never missed a beat. Now this is a workstation that can crank bits and spit them out wholesale, for audio, it easily betters the Mac Mini, was really enjoyable to discover the music and hear what this machine would reveal.

 

 

I checked the AC voltage between the shield on the USB port and earth and measured 0.000Vac, fantastic, no shield voltage, where's the noise going to go?? The Mac Mini with the portable drives on the shield of the USB compared to earth measured 85.4Vac. The mini and the wall wart both float above gound. That's direct gunge where it's not needed.

 

 

OK, from these results is a "smaller" computer with lower power or processor to keep the noise down as a first preference the only way to go? This process needs a good rethink as to why this practice doesn't add up with the improvements occurring in my system with a much supposedly larger noise maker. Several reviewers discussing the Aurender servers share a common ground, that the Aurender sounds better than the Mac Mini. This concept is another aspect of confusion as the Aurender is a purpose built machine for audio, still a computer. They trumpet low noise due to specific processing, which has merit, so why is a Workstation capable to the same degree.

 

 

For the OP, if your DAC can handle rubbish from the computer, you're 80% there to determine that you need not agonise over the choice of components for your server.

[Jabs1542]

One and a Half: How are you checking the USB shield to earth ground? Is this a meter between USB pin 4 and the ground plug going into the wall? I'm interested to see how mine measures up, floating grounds have always been a problem in audio. I have a Granite Audio Ground One on my system trying to catch that elusive ghost and would be interested to learn how to meter and measure the floating grounds.

[One and a half]

The USB cable's shield is bonded to the frame of the connector, in most cases there's enough metal to touch a DMM probe. Pin 4 is 0V from the host and should normally be above earth.

[sandyk]

I checked the AC voltage between the shield on the USB port and earth and measured 0.000Vac, fantastic, no shield voltage, where's the noise going to go?? The Mac Mini with the portable drives on the shield of the USB compared to earth measured 85.4Vac. The mini and the wall wart both float above ground. That's direct gunge where it's not needed.

 

One and a half

Interesting results. Floating devices using SMPS are often a P.I.T.A.

It's good to see that a workstation is capable of such great results without a lot of expensive after market gear, special PSUs etc.

I look forward to reading results of your further investigations in this area.

 

Alex

[One and a half]

One and a half

Interesting results. Floating devices using SMPS are often a P.I.T.A.

It's good to see that a workstation is capable of such great results without a lot of expensive after market gear, special PSUs etc.

I look forward to reading results of your further investigations in this area.

 

Alex

 

Why I checked this on the workstation was derived from a typical setup of computer/ifiUSB/USB2.0 powered hub/AC grounded DAC. The elevated voltages above ground was a real mess, some of the SMPS wall warts measured typically 80-90V to earth, some a bit lower. If you connected them all together, it was a real soup mix.

I hope to make a drawing and present as a new thread, really something to be aware of, it makes the C in EMC a joke.

[sandyk]

Why I checked this on the workstation was derived from a typical setup of computer/ifiUSB/USB2.0 powered hub/AC grounded DAC. The elevated voltages above ground was a real mess, some of the SMPS wall warts measured typically 80-90V to earth, some a bit lower. If you connected them all together, it was a real soup mix.

I hope to make a drawing and present as a new thread, really something to be aware of, it makes the C in EMC a joke.

Unfortunately, with a 50HZ 240 VAC system the voltage reading can be as high as 120V.The same type of scenario applies to most modern DVD and BluRay players also, unless they use Linear power supplies.