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Everything posted by Clockmeister

  1. For all of you state side guys try Chris @ Vh Audio https://www.vhaudio.com/search.html?ss360Query=fuses
  2. Hello pkane2001 Apologies I did not see your reply. I am sorry but this is just basic R & D that should have been performed before it got anywhere near asr (or public domain access media). I appreciate they have rectified the situation now, however it should have never have got to that point in the proceedings in the first place, which projects sloppy business practices. Yes the fact they have put things right and make sure acceptable QA in place is good move, but then it was business suicide to let your product loose with an agenda filled third
  3. Fas42 Pretty basic requirements there, if this is want you wish for then DSP is your friend I believe its been on the market for one form or another for many years in many products, whether it accurately does this is another matter 🤔
  4. tapatrick As someone who spends his life with measurements of some form or another for various EE work they are important to greater or less degree according to the project involved or the end product being designed. With regard to audio, the accepted holy grail is a ruler flat 20Hz-20Khz frequency plot, ultra low distortion/IMD and high signal to noise ratio. All of the traits are desirable yes, do they tell you the whole story no, are the helpful yes without question. I own all three BM dac's which one do I prefer the MK2 for myself it produces a more pleasing s
  5. Good Grief Are you chaps still discussing the finer nuances of which measurement is quintessentially required for choosing a dac and which analogue signal generator is preferable for viewing said IMD? and does a dac produce big staging or deeper soundscape? 😂 For all intense and purposes it looks like a early 1980's freshman debating society (entry level pyrotechnical collage) attempting to ascertain whether a large celestial body moving at near right angles to a star system causes a cup of tea to brew slightly better than using the uncertainty principle 🤔 I rememb
  6. Well the BM dac's may measure well but sonically they are very dry and matter of fact. The BM dac2 is more preferable for many listeners although not as technically competent specifications wise as the MK3.
  7. Give the level of pedantry on this thread I just felt in the interests of equality, with readers on both sides of the pond it seemed appropriate. One of the posters made a most pertinent observation regarding both camps on this subject, trying to persuade one side or the other with the benefits or system 'x' methodology compared to process 'y' methodology with their mindset buried firmly on one camp or the other is akin to convincing BMW owners that indicators are standard fitment on their vehicles or conversely Budwiser is anything other that goats piss in a can? Stub
  8. Indeed in similar fashion you could argue you same for southern states hick's 'When we having possum Ma?' or UK West Country bumpkins with 'My luvver' similar situation I suspect.
  9. Wow, a lot of activity on this subject in the last few hours! I will clarify my previous post for you gentleman also I did not realize the 'edit' facility of the forum is for a very limited time only so the ability to go back and put things into context is very narrow. My point concerning third party clarification of a device would need to be of the use an independent certified body who testing standards and abilities were to an ISO level and inspected regularly so that these standard were in keeping with that standard. Also there testing environment is neutral and rea
  10. This unfortunately tells me a great deal about that company, any quality audio equipment producing company worth its salt would have a AP555x or similar in the design section for basic audio THD/SINAD/BW and FFT base line markers. Why do you need to send it to non recognised third party with a public agenda for affirmation? Which are way beyond all forms of electrical and mechanical testing that any of the online or printed media periodicals can obtain You would have consistency, accuracy and total repeatability, I have had the privilege 😂 of seeing PM's lab up close, its a s
  11. Paul In essence it is bring many products on to a level playing field for conducted, radiated immunity RF, common mode noise, line harmonics that could cause interference to other nearby products whether audio or not by distribution through said product. These are CE directives you have your own standard in the US called CL. However concerning audio I have many files and hours of data relating to insertion loss filter modelling and trails specifically for very sensitive equipment from instrumentation to audio. The better the filter design at the incoming ac point, the l
  12. As I have pointed out out in previous post line filtration ideally common and differential mode dual line filters would be desirable to keep the upper frequency rubbish out of the sensitive areas of the equipment. Plus its a requirement for CE
  13. Apologies Opus101 I did not realise he had publicly stated this, nothing wrong being on a mission provided you are open and transparent with your basic fundamental principles and not swayed by various outside influences
  14. I firmly believe Amir has an agenda, the premise of the asr site is good, however in reality its inhabited by biases (for both camps plus the usual over riding personalities stamping their correctness to the subject involved) maybe AP gave a preference on his purchase price? or a long term loan maybe? he purchased it outright with his own funds?. Not to bothered, however like with all equipment and the internet, information is the key, how you use and apply it is down to the individual. So if said individual has an issue or score to settle then objectivity goes out of the window.
  15. Oh this is very interesting and exactly part of my remit on a daily basis specifically power supplies of all forms. Part of of the CE validation is noise immunity of devices under test, be it dac's, streamers or power supplies. Where an AM modulation is introduced into the DUT (Immunity testing) to determine any adverse effects effects while being viewed ideally under a real time spectrum analyzer and respectable scope with bode plot ability. Other items required would be a line injector (both current and voltage) LISN (line impedance stabilization networks) both line AC voltages a
  16. I have one or two items i could name seems only fair as the good people have asked you nicely, and to keep things even you can leave out the one you have hardwired to bypass the fuses
  17. Indeed my point was at the point where the DUT actually uses the power after all the psu transmission lines and circuit board entry, so what you are seeing is a real world noise figure at the point of use. The DUT has already been characterised thoroughly so you can de-embed all of the transmission lines, fixtures and interconnects before arriving at the REAL WORLD figures. A combination of power analysers, Lecroy 12 bits scopes also time domain reflectometry with de embedding capability will help no end find the audiophoolery from the real mcoy. Clocks ultimately a phase noise me
  18. I can see this topic is quite a hot one at the moment. Measurements will help you when designing products in certain areas, other measurements are essential for CE and UL certification. Together with relevant experience, empirical evidence and and understanding of what you are attempting to achieve all go towards the attaining the end result. I feel to much emphasis in audio is paced on thd / sinad, yes these are important pointers, however recently a clutch of so called super dac's that are currently being touted as the best measuring ever, do leave a bit to be desire
  19. AnAndGate Mutec's MC3 is a word clock generator with outputs that mirror the incoming audio data sample rate it automatically changes rates according to the file sample rates This uses the pcm reclocking feature to generate the outgoing word clock rate. I believe Martin T uses his Aliexpress sourced 10Mhz clock to slave both the Ether regen and Mutec MC3 with a master 10 Mhz signal directly from that clock. The Mutec can be used as clocking distribution hub however the sample rates are derived from the incoming pcm data via one of its five different fo
  20. Good Morning AnAndGate Thinking about at the above posts I should have constructed a finial post to condense this information into bullet points. Ideal conditions:- Zero compromise:- Transmission 50 Ohm output <> 50 Ohm Cable <> 50 Ohm receive end terminal Transmission 75 Ohm output <> 75 Ohm Cable <> 75 Ohm receive end terminal Not so good:- Transmission 50 Ohm output <> 75 Ohm Cable <> 50 Ohm receive end terminal Transmission 75 Ohm output <> 50 Ohm Cab
  21. LMH For the incoming data stream not to trigger either the wave form would have to be very badly distorted on the leading edge or the overshoot would need to be in the high double figures. another possible option could be the clock recovery circuit being of mediocre design with fairly high corner stone frequency and very average PLL ability this would lead to issues and a large increase in distorted sounds if not drop outs so pretty rare for this situation to happen Yes the alignment of the audio data to word bit data would not be ideal at all, simply as the main timin
  22. Last up 75ohm cable, 75 ohm feed i to a 50 Ohm receiver, the lastly adapter added in to the chain for comparison. As you can see the degradation of the wave form is pretty obvious, and especially with word clocks the wave form actually looks like a square wave form with very little deviations is the more ideal the situtaion
  23. Now a genuine 75 ohm audio clock cable using the 50 feed into a 50 ohm receiver plus the top edge definition again
  24. Next set of images show a 50 ohm cable being fed a true 75 ohm signal to a 50 ohm receiver note the reduced PK<>PK voltage and difference in the top edge wave form
  25. As promised some results from using impedance mis matched cables and adapters. I used the lab's Mutec Ref10 SE-120 master clock as the signal generator, scope has been calibrated, all test cables 18Ghz reference ultra low loss 50 ohm, audio cables were 75 ohms matched. 50 Ohm adapter is an R&S reference 8Ghz model. First images are a base line set, 50 ohm output, 50 ohm feed 50 ohm receiver, also I enhanced the waveform to highlight the very slight overshoot to give you an idea of of a close up of the wave form top edge definition.
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