atomicbob's SMPS Noise Nuke for HP amps with external SMPS

Discussion in 'Headphone Amplifier Measurements' started by atomicbob, Sep 26, 2017.

  1. Luckbad

    Luckbad Basshead - Friend

    Friend
    Joined:
    Sep 27, 2015
    Likes Received:
    1,655
    Trophy Points:
    113
    Location:
    Laguna Hills, CA
    Home Page:
    Is it sad that this thing has me more geeked than any other piece of audio gear right now?

    Would love a couple more internal shots to show where the wires are going.

    Thanks for putting this thing together. Really awesome piece of kit! Sell it to people at CA for $399 a pop.
     
    Elnrik likes this.

  2. atomicbob

    atomicbob Friend

    Friend
    Joined:
    Sep 27, 2015
    Likes Received:
    3,149
    Trophy Points:
    93
    Location:
    On planet
    And Dino wins the Rock of Gibraltar.:D
     
    Elnrik and Dino like this.
  3. Chris45set

    Chris45set Rando

    Joined:
    Jul 25, 2017
    Likes Received:
    4
    Trophy Points:
    3
    Location:
    Omaha
    Thanks for this, it does look extremely interesting and (maybe) simple to implement.
    Could this be adapted for the 48V supply used by Horizon?
    And if so, what changes would need to be made?
    Chris
     
  4. Cspirou

    Cspirou Friend

    Friend
    Joined:
    Sep 27, 2015
    Likes Received:
    1,131
    Trophy Points:
    113
    Location:
    Irvine,CA
    The caps are rated to 63V and he’s using a heavy duty inductor. You can use it without any changes.
     
  5. atomicbob

    atomicbob Friend

    Friend
    Joined:
    Sep 27, 2015
    Likes Received:
    3,149
    Trophy Points:
    93
    Location:
    On planet
    Look near the top of the first post for the words:
    It will work with any external SMPS or LPS between 1 and 48 VDC with current less than 2A.
     
    Thad E Ginathom likes this.
  6. Thad E Ginathom

    Thad E Ginathom Friend

    Friend
    Joined:
    Sep 27, 2015
    Likes Received:
    2,215
    Trophy Points:
    113
    Location:
    India
    Way not-sad! An audiophile gadget that is cheap and measurably useful? This is revolutionary!
     
    Cryptowolf likes this.
  7. crazychile

    crazychile Friend

    Friend
    Joined:
    Jan 19, 2016
    Likes Received:
    292
    Trophy Points:
    63
    Location:
    Eastern Iowa
    I coulda sworn that was from Zappa’s “Thing Fish”......
     
  8. Armaegis

    Armaegis Friend

    Friend Contributor
    Joined:
    Sep 27, 2015
    Likes Received:
    2,447
    Trophy Points:
    113
    Location:
    Winnipeg
    So if it's so easy to make a noise nuke, why don't the manufacturer's do it?
    purely a cost/size/weight thing? are there downsides?
     
  9. k4rstar

    k4rstar Friend

    Friend
    Joined:
    Jun 11, 2016
    Likes Received:
    2,014
    Trophy Points:
    93
    Location:
    Canada
    Because going overboard to filter noise like this provides nice looking measurements but has detrimental subjective effects. You may experience a loss in dynamics, immediacy, and low-level information, even if you notice improvements in macro-detail retrieval and transient cleanliness. There is a sweet spot when it comes to filtering, and usually less is more.
     
  10. Luckbad

    Luckbad Basshead - Friend

    Friend
    Joined:
    Sep 27, 2015
    Likes Received:
    1,655
    Trophy Points:
    113
    Location:
    Laguna Hills, CA
    Home Page:
    It's also not particularly inexpensive.
     
  11. Cspirou

    Cspirou Friend

    Friend
    Joined:
    Sep 27, 2015
    Likes Received:
    1,131
    Trophy Points:
    113
    Location:
    Irvine,CA
    This is basically for the regular off the shelf SMPS for charging laptops. The purpose built SMPS made for audio has all sorts of extra filtering.

    Plus you see the size of the inductor AtomicBob uses? It’s pretty big.
     
  12. 93EXCivic

    93EXCivic Rando

    Joined:
    Oct 10, 2017
    Likes Received:
    16
    Trophy Points:
    8
    Location:
    Alabama
    Very cool. I am definitely building one of these for my modified Bravo V2 hybrid.
     
  13. winders

    winders Friend

    Friend
    Joined:
    Feb 13, 2017
    Likes Received:
    527
    Trophy Points:
    93
    Location:
    San Martin, CA
    @atomicbob

    Have you tried grounding the negative line output of an SMPS to see what effect that might have? I ask because there has been some discussion about this on a another forum. John Swenson, who by all appearances seems to be pretty smart, has suggested doing this as a way to reduce SMPS noise injection. I don't have the equipment to test something like this so I am unsure as to the value of the suggestion.
     
  14. atomicbob

    atomicbob Friend

    Friend
    Joined:
    Sep 27, 2015
    Likes Received:
    3,149
    Trophy Points:
    93
    Location:
    On planet
    When making measurements, I am careful to have a single ground reference for the device under test and the measurement system. Ground loops often introduce additional noise. Each setup undergoes several different points of connection to define that single ground reference and the one that yields the best results is used for obtaining data. In this case, the negative side of the PS-III amplifier is connected internally to the shield of all RCA connectors, both input and output on the amp. A ground was established between the negative side of the PS-III and ground lug on the dScope to yield best performance.
     
    Dino and Luckbad like this.

Share This Page