1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.
  2. Where we are now: The site is back up and running! The character set encoding issue has been fixed so old posts should now look ok. I am currently working on themes/skins etc and I will be deleting the temporary green skin very soon as it has many issues. I will do a very quick variation on the stock blue skin first just to get a light-grey background and san-serif font, and I will set this as default. Later this week I will hopefully add a professional third-party skin in pfm colours (life is way too short to do this crap myself, and I've found one I really like than needs next to no tweaking). We are getting there slowly...
    Dismiss Notice
  3. May I please request people check and update their email address if it is out if date. I ask as I’m getting countless bounce errors as the server fails to send notifications through etc. I’ll eventually figure out how to send these to a black hole somewhere, but it makes sense to address it at source as quite a few folk are obviously not getting the thread and conversations notifications they have set in their preferences.
    Dismiss Notice
  4. Things you need to know about the new ‘Conversations’ PM system:

    a) DO NOT REPLY TO THE NOTIFICATION EMAIL! I get them, not the intended recipient. I get a lot of them and I do not want them! It is just a notification, log into the site and reply from there.

    b) To delete old conversations use the ‘Leave conversation’ option. This is just delete by another name.
    Dismiss Notice

The edge of audibility

Discussion in 'audio' started by Steven Toy, Jun 27, 2011.


After listening to the two files...

  1. I prefer m2467.wav

  2. I prefer m8742.wav

  3. I have no preference

Thread Status:
Not open for further replies.
  1. Steven Toy

    Steven Toy L3 Toy

    Simon left the building about an hour and a half ago.

    It was good to meet you properly Simon.

    We performed two tests:

    1) Swapping the plugs over in the mains filter between the one that feeds the DAC/output stage and the other that feeds the transport.

    2) Connecting everything via the mains block and directly into the wall.

    Apart from saying that Simon comes over a lot better in real life (like most of us), those monitor Sony in-ear phones of his are probably the best headphones I have heard. I would love to hear them via a valve headphone amp.

    As we largely agreed with each other over what was heard I will leave it to Simon to explain.
  2. sq225917

    sq225917 situation engineer

    Here's the detail.

    Popped round to Steven's, disappointingly he only has one head. Played a selection of music, some of his some of mine, some we both owned. Basically acclimatized to the sound of his set-up, and his room- then the swapping started.

    Steven's cd player has two power feeds, one from a Tom Evans box (Lithos I assume) and another coming from a standalone PSU he had made, both of these were being fed via a mains filter. The two PSU feeds go to either the DAC/Output stage or to the front panel/servo etc.

    We swapped them about a few times, so either DAC/output board or servo etc was the first item fed from the mains filter. Two sockets, similarly wired, one closer than the other to one side of the mains filter. Honestly I'd have to say that one side of the box does appear to be better than the other- it sounds different, different enough not to need cajoling into giving an opinion- slightly more slam in the bass one way round than the other.

    I'm not sure I could identify it blind either way, but the feeling it was a genuine difference was significant, certainly enough to say so here. I'd like to see inside to see what the differences are and maybe measure to see what the differences are if any in terms of impedance.

    Then we moved on to the AudioWorks mains block, either plugging into this and then into the wall or plugging all feeds for cd, pre and power amp directly into Steve's wall. His wall socket for his hifi appears to be a completely separate, ie two 32amp tails exit the meter before the main consumer board and wind there way to the hifi room where they go into a Memera CU and 4 MK socket.

    I couldn't spot any difference between into wall direct or into MusicWorks block and then into wall. Steven said he was surprised that was struggling to hear the usual difference, this was the first time since he got rid of his Bel Canto cd player that he had tried the switch and also the first time with the mains filter in place. So I set up the Sony recorder and recorder 4 excerpts of Ray Lamontagne, the same cut each time, twice via the wall, twice via the MusicWorks block and once each with a low frequency filter used and not used to compensate for the directionality of the microphones.

    I shall post the clips up later tonight, see if anyone can reliably spot any differences.

    And I can recommend the Freedom Brewery up the road, great beer.
  3. dave

    dave Plywood King

    Sounds like a good time was had by all and evidence that the "impossible" may just be possible.
  4. markt

    markt hello

    I'll have a listen, very interested.

    FWIW I think that hand-held recorders can give a good idea of how the room and equipment sounds so maybe starting a precedent will get something of value and get the ball rolling wrt 'getting it out there' It can't do any harm and it makes the same old converstions much more interesting, moves them up a notch in credibility terms too, well done for putting the effort in!

  5. darrylfunk

    darrylfunk Banned

    what that the mains block didn't seem to make an audible difference?
  6. Steven Toy

    Steven Toy L3 Toy

    Not the difference I am accustomed to, no. There was perhaps a little more focus to vocals with the block but only perhaps. Previously, and with a different CD player and no filter there was a bass bloom noticeable to the point of irritation. Swapping the leads over in the filter did make a difference though and one that Simon acknowledges above.

    I am puzzled regarding the mains block. A number of twitchy keyboard warriors will be primed with the word 'placebo.'

    I would not rule out other possibilities though.

    The two Tom Evans PSUs are actually daisy-chained and are fed by one plug. The other plug goes directly into the CD player itself to feed the display and motor. The other PSU you saw, the one made by Anthony powers the preamp.
  7. dave

    dave Plywood King

    That Simon found AC plug sequence can make a difference.
  8. darrylfunk

    darrylfunk Banned

    what's strange about that?

    have not seen much of a serious report, just a nice friendly listen....neither simon or steven have stated anything about improvements really....it was just a nice little session - what are you trying to prove by making statements neither you nor i were there so why does it matter so much to you....what are you arguing a point for?
    and why haven't you commented on the fact that block or wall didn't seem to make a difference?
  9. sq225917

    sq225917 situation engineer

    So to sum up my thoughts based on listening in Steven's room.

    Musicworks mains block vs zero cost plugging into wall option- no difference.
    Swapping order of cd player PSU plugs in mains filter block- audible difference.

    I'll do the file in a minute
  10. sq225917

    sq225917 situation engineer

    So I've trimmed both files, same length, there were recorded with the same settings, same mic direction, Steven and I sat in exactly the same positions, as identical as can be.

    Sat at Steven's I couldn't make out any differences between the two, i genuinely couldn't. But sat at home, with the tracks stacked up in Decibel in a random order and just flicking backwards and forwards between tracks at random with literally hundreds of random clicks of the mouse from the other side of the room, out of screen visibility.

    Well the results are contentious, to say the least.

    Here are the files. Have fun.


    edit, files are still uploading give them 10 minutes
  11. stevec67

    stevec67 pfm Member

    This is really interesting, especially as I know Simon (SQ) to be fairly sceptical about claims and to have an analytical approach in hunting down origins of any audible differences. I would say that he is fairly unlikely to apply any expectation bias, and he has no vested interest either wayt so if he hears a difference the chances are that it exists.
  12. sq225917

    sq225917 situation engineer

    I'll have YNWAN come round later this week and we'll do it together, proper blind. Please note I just said the results were contentious- not which way they fell... ;-)

    For now if anyone who listens to them could just say if they think they can hear a differences. I'd prefer to leave any statements of which we think might be which until everyone has had the chance to listen so as not to 'queer the pitch'.
  13. Still

    Still gyldengourd

    That is very interesting - thanks sq.
  14. darrylfunk

    darrylfunk Banned

    hi si,
    did you take line level outs from steven's cd and pre amp at a fixed level too?
    just curious....
  15. Steven Toy

    Steven Toy L3 Toy

    No. He didn't as it would have taken the loudspeakers out of the loop. No sound from them equals no vibration other than from passing traffic.
  16. darrylfunk

    darrylfunk Banned

    oh cool, i see you were wanting to experience the full effect of having the speakers in the loop ....gotcha ....

    i'm disappointed you only have the one head steven....:cool:

    how are your tannoy's settling in now?
  17. stevec67

    stevec67 pfm Member

    So the hypothesis is that if there is a difference then it's the result of physical vibrations in the room?
  18. Steven Toy

    Steven Toy L3 Toy

    Not necessarily but it would be pointless to obviate that possibility so early on.
  19. sq225917

    sq225917 situation engineer

    All it can tell you is that the record/replay chain is capable of sufficient differentiation to identify qualitative differences between mains power and 6 way block, or not.

    We can theorize what the reason for the difference might be afterwards
  20. Steven Toy

    Steven Toy L3 Toy

    The band of recovering audioholics seem pretty quiet....
Thread Status:
Not open for further replies.

Share This Page