Originally Posted by stevekale
I would do a lot of homework before buying that power supply or certainly before spending more than a couple of hundred £ for it. First, it's current capability is nuts. I'd be wary that it's even true, especially given the small size of the toroids. You won't need the -12V at all and I doubt you will need anywhere near that current in the 5V and 3V3. (Think more like 3-5A max.) You will want a lot of 12V capability to drive your graphics card. Make sure it includes management of the ATX power-on sequencing - without it your motherboard may not boot. I'd also ask a lot of questions regarding how that supply is regulated. One of the big advantages of linear power supplies is that they can be relatively simple and easy to build (a bridge rectifier, a couple of filter caps, an IC regulator and an output cap and you're done). It doesn't take much to build a high-current linear supply, but building one with superb noise rejection and low impedance is more difficult. Ask how they've done the rectification circuit, snubbed rectifier/transformer ringing etc. Just because it is linear doesn't mean it's good. (Switching power supplies can be designed with very good specs - one of their disadvantages is that they are rather more complex to design and build.)
From what I can see it all looks very "basic". I love the way they have the lone LT1085 regulator for the 5VSB clamped to the bottom of the enclosure like they forgot they needed it...
I too see a lot in that chassis I don't like. Once you get above 3-4 amps, linear power supply design does get complicated. Multuiple pass transistors are needed, MOSFETs, can help reduce that need, but still you need to design the error amplifier and drive amp. Slapping in a three terminal regulator driving a pass transistor is sloppy and wrought with problems. My first choice would be an ancient 723 chip but there are also much more modern parts from TI and Maxim. I can't tell exactly what Teradak is doing but there doesn't seem to be enough parts on those boards to properly
get the current levels they specify. There could be rear surface mount chips we can't see.
Another very important feature to have is OVER VOLTAGE PROTECTION. This is highly desirable in a high current regulated linear power supply. If one of the pass transisitor were to fail and short across (which power transistors always do), the higher raw unregulated power will come across to your mother board. This will surely irreparably damage it and will could destroy the processor and memory as well. Don't forget disks and PCI cards. Again I can't tell if the Teradak has OVP but there doesn't seem to be the parts count for it. I would check before even considering this unit.
The more glaring issue is that unless you are outputting analog from your HTPC, this linear power supply idea provides no benefit whatsoever and may quite possibly compromise system stability. The digital processing is not affected by EMI/RFI noise inside the chassis and while the AV clock generation PLLs would be, a competent HDMI or AES card will filter that locally, and if they don't, a quiet linear master power supply won't help. The raw power rails will have a lot of noise from the computer circuits. using a linear master supply won't fix that. If a circuit such as a clock PLL needs clean DC, you have to filter it locally at the circuit.
I recently moved to JRiver from VLC/CollectorZ and now have all my BluRays ripped which VLC didn't support (at least for me). I run two audio profiles. For my ripped DVHS library I output bitstream via SPDIF into a Lexicon MC8. For BluRay rips I use a Lynx AES16 which goes around the Lexicon.
My audio is very good. I can't see any room to improve it on the server side. I even think the AC3 sounds better versus the VLC player but I know that can't be as both were bit streamed though the exact same hardware. Placebo effect in my case.
P.S. Looks like somebody forgot to shoot those yellow sleeves on the connectors with the heat gun. I'm sorry but this box is yet another product in the long line of audiophile foo foo boxes. Not well thought out at all IMO. Just use a good name brand PC power supply - about $100. You will be much better off.