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Simonon

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About Simonon

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  • Birthday 05/10/1966

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  1. Simonon

    Let's talk jitter.

    It would be great to list and discuss the types of DA converter chips in use on DACs and common circuit designs which vary considerably. You could start with 14BIT TDA1540 and work up to DA converter chips in common use today PCM 5122 for example. I suspect clock jitter has little influence here but the DA chipset and topography does make audible differences between DACS. One also needs to consider the output stage with the types of opamps used including the use of tube buffers in some, lampizator for example. The clock is only a small part of the puzzle.
  2. Simonon

    Let's talk jitter.

    This again sounds like marketing to the audiophile that has been told that 2nd harmonic distortion sounds nicer......this is essentially a myth. The reality is that distortion levels on modern amplifiers is so low in the order of .001% for example at deafening listening levels. Frequency response is ruler flat across the audio spectrum and beyond. 2nd or third order distortion is no longer relevant in my opinion. It is great marketing to imply an amplifier is tuned for 2nd order distortion to audiophiles as it a common myth to say valve amplifiers sound better than solid state due to the presence of second harmonic distortion. The reality is that distortion is close to zero on a modern amp at normal listening levels.
  3. Simonon

    Let's talk jitter.

    I beg to differ with the following points. The claim and jitter figure is based on a sighted listening test by a designer with a vested interest in marketing of products. No doubt he is a clever guy but the fact remains this claim may be based on maeketing of PS audio product and the figure should not be taken as reference for this reason. Isnt this example part of the problem with this industry and is always a touchy subject. Again my opinion
  4. Simonon

    Let's talk jitter.

    Interesting as PS audio marketing techniques and Paul Mcgowans blog were discussed in depth by some in my audio myths and misconceptions thread. Nothing against PS audio products but some of the claims made by them I find questionable and purely for marketing to the non technical audiophile. Therefore I would take this claim with a grain of salt. Imo claims like this tarnish the name of a good product but this is my personal opinion and I accept others may differ.
  5. Simonon

    Let's talk jitter.

    I wonder if he is also into power cords and bybees. I take these claims with a grain of salt. Maybe he also writes equipment reviews.
  6. Simonon

    Let's talk jitter.

    So here is a question that somebody may be able to answer Why is their a revival of interest in the perceived analogue sound of TDA 1540 equipped early generation 14 bit CD players and later 16 bit TDA1541 dac chips. I note one popular methodology is to use a number of dac chips in parrallel to average the slight variation in timing of these chips again for a perceived more rounded analogue sound or so the marketing says. Would the ability to vary clock jitter have a similar affect to suit personal tastes? Would a jitter free clock sound harsh and sibilant when compared to the same dac chip with a relatively high amount of clock jitter. I am trying to gain an understanding of how jitter will audibly affect sound when compared to the use of dither in digital mastering for example.
  7. Simonon

    Let's talk jitter.

    The first part doesn't sufficiently characterise jitter, the latter needs unpacking - what does 'not even worth a mention' mean? My bad with the terminology in regards to phase noise. One of the measurements I performed regulary was phase noise and jitter measurements of the local oscillator on digital broadcast transmitters using some very nice high end test gear. Phase noise actually became problematic when a precision 7v power supply became noisey in the local oscillator synthesiser module of a particular high power digital television transmitter causing a phenomenom called centre carrier breakthrough which ultimately affected the MER or modulation error ratio at the output of the transmitter. We had a separate program on the spectrum analyser to measure the phase noise of the local oscillator. I started using this equipment to measure DA converter clock jitter and phase noise of a bunch of dacs and cd players I have out of interest and fun. I found phase noise of the DA converter clock to be so low it was negligable being so far down in the spectrum analyzers noise floor it was hard to gain a meaningful measurement and in my opinion to not be a factor that would audibly affect sound. Likewise even on a basic clock in an entry level cd player measured jitter was in the order of pico seconds. I agree that I may be missing something here or their were flaws in my methodology as my background is in digital broadcast and Rf which is why I find this thread interesting. I always like to be proven wrong but not without a robust argument[emoji3] I would like to experiment more with digital music servers, DA converter chips and clocks but find the cost hard to justify for an experiment when the performance of modern equipment is so good. Great thread.
  8. I have some Sinatra, Ella Fitzgerald and Nat King Cole mono lps from the 50s purchased at my local Flea market for around 2 dollars each. If I find a mono lp in good condition I always have to buy it. A quick visual inspection at the vendor stall showed they were very good plus condition. An ultrasonic clean and vaccuum when home and straight on the Thorens with a Dl301 mk2, flicked my pre to mono with a modest amount of expansion via the dbx 2bx expander. The result was silent vinyl with good depth and great dynamics. Any modern stylus is going to get deep into those grooves so a good clean is mandatory. Most of the cartridges of this era were ceramic with huge eliptical stylii and little thought given to tracking weight so many old lps wore out rapidly. I am becoming more keen to purchase an audio technica mono cart to compare sound although I am impressed with the quality of sound using my current denon cart. My speakers and tube amps are authentic from the era being built in 1963. Here is a blast from the past with my Hmv Monaco record player in great condition found at you guessed it....the flea market a ground breaking modern unit with germanium transistors. I have a soft spot for this era. Digital music is so boring when compared to this [emoji3]
  9. Simonon

    Let's talk jitter.

    All of the jitter measurements of oscillators that I have ever measured are in the order of 10 to 50 pico seconds with phase noise not even worth a mention. These measurements being with a calibrated 1ghz R&S cro and spectrum analyzer. I am currently mucking about with an iq audio dac plus costing $50 on a Raspberry pi model 3 running Volumio. I have to say it sounds stunning playing back a flac, even on headphones via the inbuilt head phone amp. All for $150 dollars including the Raspberry pi plus case and power supply. Modern electronics has come along way with a lot of hardware packed in a tiny chip. With a limited number of chip sets available I do not understand why some dacs cost upwards of 5 grand given the performance of this Raspberry Pi and IQ audio dac. The crazy plan basically for something to do and a challenge is to replace the completely stuffed reel to reel section of an akai tube M8 with a Raspberry pi and touch screen ( making it look like a steam punk reel to reel and cool). The IQ audio dac will run into the lovely 6w single ended tube amps. I rigged it up on the work bench into my high efficiency Wharfedales to check if this is worth the effort and it sounds very nice even without rebuilding the amps. Tidal Hifi streaming is impressive at this early stage. So given performance of this little IQ audio thingy is jitter even worth considering.
  10. I just use the mono button on my preamp when listening to mono lps. It does improve the sound by cancelling out any noise picked up by one channel of a stereo cart. I should try a mono cart on my Thorens Td320 as its simply plug in with a spare head shell. I prefer the mono album versions of early Rolling Stones, Bob Dylan and The Beatles. Many of these classic albums were intended to be in mono with stereo coming later. The depth, solidity and simplicity of a good mono lp is something to behold. Any one heard the 1956 mono version of Gene Krupa Drummer man.....awesome stuff.
  11. Simonon

    Let's talk jitter.

    Hifi was an exciting place in 1961 by this article in a magazine. I wonder when the words "synergy, black background, nano technology, air and many other marketing terms found their way into the audiophile marketing vocabulary. Modern reviews make for entertaining reading and are as believable as the diatribe on a shampoo bottle where nano technology and synergy also seem to appear. I say long live Hifi diy which with the likes of raspberry pi is having a revival. The best way to learn about digital audio and topics such as clock jitter.
  12. Simonon

    Let's talk jitter.

    Lets get back onto jitter. I have learned alot from this thread and its knowledgeable contributors. The reviewers in magazines will never change and there will always be audiofools that believe all they say....I find it entertaining, to be frank I would find audio boring if it were purely technical. I seem to remember starting a little thread that created the " great audio debate section" where myths and misconceptions were discussed in depth how it survived 2600+ contributions and 27k views without getting shut down was a miracle. Much was written about audio reviewers I recall. Suggest these rants stay out of this thread as it reminds me of the song " the wheels on the bus go round and round". Please nobody mention dou*** b***d t**** next. On a technical note this thread has made me start looking more closely into I2C Raspberry pi Dac boards with analogue rca out. It would appear that many variants have relatively noisy jittery clocks if the reviews hold true. Can somebody recommend one as I have a project in the planning stage. To my ears volumio on a Pi3 with a Hifiberry dac hat sounds good but I have nothing to compare it against.
  13. Simonon

    Vinyl disillusionment

    I would see how it sounds on the window sill as it is easy to do. The sound improvement may make you want to explore further. If you play with other options at least you have a reference. Anything other than the window sill will be a compromise for isolation as you will never eliminate it with your floorboards and cabinet it will also cost more. I can picture what you need to do but unfortunately I am in Adelaide. A nice cover will protect your turntable when not in use from the sun.
  14. Simonon

    Vinyl disillusionment

    You should come out
  15. Simonon

    Vinyl disillusionment

    Any local stereonet members adept at carpentry able to offer suggestions to utilise this windowsill and make it look nice? Remember it must be completely isolated from the floor.
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