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Is The Running In Of Electronics A Myth?

Discussion in 'audio' started by maxflinn, Sep 8, 2013.

  1. maxflinn

    maxflinn Tulsi Gabbard 2020.

    I should really ask - can the running in of electronics cause an audible change, or is that a myth?

    I say no, the running in of electronics will not cause any audible change.

    What do you think?



    Cheers.
     
  2. Jodet

    Jodet pfm Member

    You are mistaken. Capacitors and other components do break in.

    Most manufacturers admit this, many mention it in their owners manuals.

    Move on.
     
  3. dtd

    dtd pfm Member

    Agree with Jodet - even speakers have a break in period which has been measured before and after. I'm sure there's evidence for capacitors and such too.
     
  4. Joe Hutch

    Joe Hutch Mate of the bloke

    I'm an English graduate, so I have no opinion on what's feasible or not with electronics. The fact that black boxes can produce music at all seems miraculous to me.
     
  5. Cereal Killer

    Cereal Killer fourhundredandthirtytwo

    Put the question across a little differently; is the break-in/running-in of electronics audible? even is we can clearly understand the theory as well as tried, tested and measured results exist?
     
  6. maxflinn

    maxflinn Tulsi Gabbard 2020.

    Yeah that's what I'm asking really so I've edited my OP, cheers.
     
  7. PaulMB

    PaulMB pfm Member

    I bet a £25 donation to pfm that this thread tops 100. Any takers?
     
  8. bec143

    bec143 pfm Member

    I wouldn't buy you didn't like from the get go with the expectation that it will some how improve with time. Exception is speakers- recently had a great example of this with a Celestion in a guitar amp. Major change with breakin.
     
  9. Joe Hutch

    Joe Hutch Mate of the bloke

    It's not something I've ever experienced (as in 'this product sounds shite at switch-on, but 3 hours later it really sings' or 'when I first heard these speakers they made me claw the walls, but now, six months later, you would have to prise them from my cold, dead hands'). But then I'm pushing 60 and probably not 'discerning' enough to notice such things.
     
  10. dave

    dave Plywood King

    It's quite audible here though it doesn't make or break a component IMO.

    Additionally, I've found the difference between fully "cold" and fully "warm" all but disappears after the first year of use if allowed to run 24/7 and a few power cycles are performed during this time.
     
  11. Cereal Killer

    Cereal Killer fourhundredandthirtytwo

    a shite product will always be that, but a good product can get better after its warmed up - for me, break-in time is about 20-30 mins :)
     
  12. dave

    dave Plywood King

    I've actually owned one component which sounded "worse" if left on longer than a few hours or overnight. This was a Hafler DH-101 preamp I owned back in the 70s. It did save me a few pennies in electricity I suppose while I owned it.
     
  13. martin clark

    martin clark pinko bodger

    Yes, certain components especially large or electrolytic caps have a run-in period in which they 'form' properly from first use and (for example) the leakage currents drop.

    The knock-on effect from new leaky caps can be fairly-easily measured in terms of noise currents and even bias conditions and yes, from experience I think it does have audible effects. Noise from new electrolytic coupling-caps being leaky can have a subjectively quite unpleasant effect even if the objective magnitude of the 'problem' is very small (few tens of uA)

    I'd suggest this accounts for most such 'run-in observations' - its the most-obvious issue by an order of magnitude or more. In certain manufacturer's approaches, it will be audible. But from first use, or disuse after several months unpowered storage, such capacitor settling is all over in 24hrs or so of constant power (unless the caps actually need replacing). The idea that anything needs oh, 100s and 100s of hours of 'burn-in' is almost entirely bollocks.

    I've also met a similar effect in crystal oscillators in the first few hours of use, which should not be a surprise - they are very definitely electro-mechanical devices.
     
  14. sq225917

    sq225917 situation engineer

    To follow on from Martins post.

    I recently built a few versions of the Paradise phonostage from over on diyaudio.com. It has in it a series of electrolytic caps that see remarkably little voltage or current and these are part of the output stage offset compensation circuit. it took close to 100 hours for the output offset to drop to a steady level. The first time I measured it after turn on it was swinging wildly, jumping 10mv in either direction instantaneously and going from -100mv to +100mv over the course of a couple of hours, (ie it had a lot of short term noise on top of a larger long term trend). After half a day these values had both dropped to half this amount and proceeded to continue to follow that trend for the next 3 days by the end of which I was able to trim out the offset bias with the trim pot and it has remained at 0.0v ever since despite repeated period of disconnection.

    The psu for this phonostage has two class A shunts in it, these take about 15 minutes to settle from cold and during that time there's some lack of solidity to the sound.

    So for me the answer is clear, I not only believe in warm up, but I also have proof of 'burn in', though i think the term is somewhat misused. Those parts that do show signs of burn in also tend to be those are 'wearing out' from their first use onwards, IMLE.
     
  15. martin clark

    martin clark pinko bodger

    That's a very good example Simon - when the voltage across it is deliberately-made very small then any electrolytic cap is going to take a long time to hold form well enough to minimise leakage.

    (For the wider discussion - yes, there are reasons to electrolytic caps like this, such as when the design requires a capacitance [low impedance] that just cannot be achieved in film caps or other better forms)
     
  16. TheDecameron

    TheDecameron Unicorns fart glitter.

    Modern components don't need running in at all. The older stuff with point to point wiring, valve holders and even the PCB based designs before computer placed SMD boards was never as accurately built so it was sensible not to go past about 7 on the volume for the first 60 days or so. These days the boards are far more precisely made to ultra fine tolerances so you can go as loud as you like from day one with no need for running in.
     
  17. 1950redwing

    1950redwing Active Member

    Thank you, I needed that...a good laugh

    Red
     
  18. Arkless Electronics

    Arkless Electronics Trade: Amp design and repairs.

    I totally agree with Si and Martin on this one.... It's been especially brought home to me in my R+D on my new phono stage (not for the first time but never to such a measurable extent) it's very real and can be measured... in fact some variants of the circuitry I'm experimenting with have been virtually unusable until left to run in overnight!
    I have a batch of electrolytics here that even has a warning on the box about it and even mentions which way up they should be for so many hours before being run in! (yes really!)
     
  19. dave

    dave Plywood King

    Nice to see progress discussing a topic that's been taboo @ PFM for the last three years gentleman.
     
  20. timeout

    timeout ignorance is bliss

    myth. yes.

    if it sounds nice, it will sound nice to you right from the beginning

    to say, burning in and a few months later it sounds nice is all BS.
     

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