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  1. Alex hi, You may have misconception about how complex / expensive these server PSU measurements are to perform. Server LPSs are not ultra low noise units and the measurements we are discussing are simple, so they are straight forward to make and do not need sophisticated or expensive equipment. An oscilloscope and an electronic load for say £1-2k in total sourced from good manufacturers will do this. Its worth remembering as well that the same pieces of equipment are the tools required to develop, test and produce supplies, so they should already be on hand.
  2. The first 2 sets (copied below again) are my personally thoughts on what I would look for. The first case 1) for me would get the job of powering a DC-ATX or a single music server rail done, whilst the second case 2) would be for a more expensive class of device. Transient response, ripple and sag under load are quite basic parameters but I think they do have some correlation with SQ, and so are useful. The last set of figures 3) below are actual measurements taken from the 12v, 10 amp LPS module of the system I have built. 1) - to get the job done. "Start at < 20
  3. Defiantly agree, but has been addressed. For the project I am working on reliability and flexibility are two of the key requirements, so this challenge has had to be addressed. I think the result (described below) is possibly one of the most flexible server power system I have come across for high end audio servers. The system is certainly not a set of discrete power supplies, hot wiring ATX control wiring and crossing fingers for the "Kerr-thunk" as power is applied is too exciting / potentially expensive . All very important points that have
  4. Hi One and a half, Having said it would probably be helpful for people trying to choose a PSU for their systems if measured performances were given more, you are right, I really I ought to say where power measurements are at here 🙂. I have 5 LPS modules in the server I am working on that provide 5 linear ATX rails plus a few auxiliary rails for other stuff. Each module has 3 pcbs in the design which have been developed over a three+ year period. The modules are all specifically designed and optimized for their respective rail voltages (ie circuit differences - not a trim pot o
  5. I think it would be good to see measured performance specifications provided as well. As a general observation there are some large ticket LPSs out there for audio systems but few vendors provide measured specs for products. At the price levels we are operating at, it's not unreasonable to be looking for similar measured performance to lab class LPSs from companies like R&S Tektronics and Agilent. So ball park or better than: Sub 50 uSec 60% load transient recovery times. Sub 2mv rms ripple and noise. Sub 2mv rail sag from 10 to 100% of rated load.
  6. They look very well presented but there is an absence of measured performance figures, which seems to be the standard for audiophile supplies. The hifi wires, caps cryo parts etc etc, may be good tick boxes for some potential customers but measurements should be the starting point. Steady state noise figures at rated load would be nice as a start, but transient load response performance is proberbly the better paper indicator. Start at < 200usec for 5 amp transient rail voltage recovery with a critically damped response and <20mv over / undershoot. This is is typical for low to medium co
  7. The production slot has moved back a week because of a small delay in a prior jobs, machining starts a week on Monday, I will be dropping by the factory then to decide the finish and look over some other work. So all good thanks. I will post some updates as things progress.
  8. That's very nice close in performance for a ~50Mhz carrier. Is this with a sinusoidal or HCMOS output ?
  9. I spotted this too, but was charitable and assumed a typo, 100HZ should have been 100KHZ perhaps ? But even then is "strong" performance getting to -172dBc at 100kHz. Regardless of the clock details I think this is worth a look.
  10. @StreamFidelity great post this is an interesting route to look at. I had actually considered spinning up a PCB for a to UTP to fiber converter for isolation but hadn't realized how many are available and how cheap they are to buy . Personally I have been focused on improving timing and SI of network transmission by working inside the devices that are transmitting and receiving the stream (music server / audio server). Putting additional devices in to the network path such as switches and hubs introduces a multitude of additional variables that then need work. I guess y
  11. Indeed, Its 3000 odd pages long but there are a few gems in there. It was bedtime reading for me for some time when I was working out what platform to move to after developing the X99 server. Sign of an obsessed audiophiles I think 😀
  12. Hi, My first post in this epic thread so hello to all ! @StreamFidelity hi, perhaps I would not go as far as saying this is "solved". It is an excellent starting point, the C620 architecture is the best I have come across so far and in large part I think because of its clock subsystem design. This comment applies to Intel systems, I haven't used or looked deeply at AMD. The C620 is still a starting point for me however. A few posts further down in the "Building a DIY Music Server with custom made parts" thread I also say. "I used to use e
  13. Its not nice at all when a board dies without an obvious reason. I am not sure if clock replacement is a regular modification so apologies in advance if the following are things you know / have tried. CPR for the buffalo, just make sure you have a mask on they can be gooey around the mouth First voltages. Were you able to check the peak to peak or RMS voltage from the output of the Xtal that was originally on the board ? These days 0.8 - 1.2v peak to peak clock voltages are not uncommon as VCore voltages get lower with internal processor frequency getting higher. If the
  14. Black would work better for heat emission from the CPU cooling block, but the extra heat emitted would be inside the case rather than being transferred out of the case via the heat pipes / case's external heat sinks. I don't think the difference between black v's silver finish should be too great so aesthetics will probably be the decider . Black would look cool though.....
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