+ Reply to Thread
Page 1 of 4 123 ... LastLast
Results 1 to 10 of 34

Thread: DIY BMU build

  1. #1
    Bigman80 Guest

    Default DIY BMU build

    Here it is. All built but need to swap the 10a MCB for 6a MCBs

    It has removed the intermittent powerline adapter noise. Only problem is, I have a buzzing sound now.

    Any suggestions?

  2. #2
    Join Date: Jan 2009

    Location: Essex

    Posts: 31,853
    I'm openingabottleofwine.

    Default

    Looking good Oliver,

    But the MCBOs need to be ganged, so that if one trips out due to a fault condition, both live (115V) conductors are disconnected. Ideally you should use a 2-pole ganged RCBO.
    Barry

  3. #3
    Bigman80 Guest

    Default

    Quote Originally Posted by Barry View Post
    Looking good Oliver,

    But the MCBOs need to be ganged, so that if one trips out due to a fault condition, both live (115V) conductors are disconnected. Ideally you should use a 2-pole ganged RCBO.
    They are connected by a metal pin, Barry. Of one trips, they both trip. Tried and tested.

  4. #4
    Join Date: Jan 2009

    Location: Essex

    Posts: 31,853
    I'm openingabottleofwine.

    Default

    Quote Originally Posted by Bigman80 View Post
    They are connected by a metal pin, Barry. Of one trips, they both trip. Tried and tested.
    Ah - I couldn't see that from the photo. It would be better still if a two-pole residual current circuit breaker was used, to provide protection against asymmetrical current leakage.
    Barry

  5. #5
    Join Date: Oct 2008

    Location: Glasgowshire

    Posts: 9,656
    I'm Gary.

    Default

    The buzzing probably means you have DC on your mains.
    Get a DC blocker in there Oliver, either in the chassis if you have room or an external box between the mains feed on the wall and BMU.

    Fitted one to my Airlink unit recently, buzzing is gone.


    THe BMU, whats your perception of sound quality changes?
    AC POWER
    Hardwired 10kVA balanced mains powering entire system
    AMPS
    Meridian 557 power Amp (Modded) / PS Audio BHK Preamp (Modded)
    SPEAKERS
    Wharfedale Evo 4.4
    DAC
    PS Audio Directstream (Modded)
    TURNTABLE
    Pro-Ject X8 balanced output via XLR / Ortofon Quintet Blue cartridge
    PHONOSTAGE
    Pro-Ject DS3 B balanced Input (TT and Phonostage powered by Pro-Ject Power box RS2 linear psu)
    DIGITAL
    OPPO 203 (Modded: Linear PSU, i2s output to Dac) - Roon Endpoint, HDMI input used for all things Streaming/ PS5 /AppleTV ... also good for movies apparently?
    MUSIC PLAYBACK
    Tweaked AP-Linux based Roon Server into Oppo 203 as Roon endpoint
    Ipad Roon Remote.
    Apple Music/ YouTube via AppleTV, fed to Dac via Oppo HDMI input/i2s output to Dac.
    SPEAKER CABLES
    Biwired: Duelund DCA10GA (Bass) Duelund DCA16GA (mid & treble) Duelund 12DCA used as jumpers (On
    "Blackcat Cable" Chris Sommivigo's advice - yup, even with biwire it sounds better - and it does)
    INTERCONNECTS
    All Balanced: Ghost+ recording studio XLR cables

  6. #6
    Bigman80 Guest

    Default

    Quote Originally Posted by Gazjam View Post
    The buzzing probably means you have DC on your mains.
    Get a DC blocker in there Oliver, either in the chassis if you have room or an external box between the mains feed on the wall and BMU.

    Fitted one to my Airlink unit recently, buzzing is gone.


    THe BMU, whats your perception of sound quality changes?
    There is a DC blocker in there, it does reduce mechanical hum.

    Well, it seems the BMU is not having the desired effect. I am getting more hum now than previously. I have stripped everything out and put in place a multi plug which I built. Very simple, just wired with standard flex and switchless sockets and stared plugging things in one after the other.

    I have some hum on the Phonostage which I hadn't realised but the Rothwell SUT is adding to that. The IC cables I use aren't shielded so that needs addressing. But it's 90% quieter without the BMU. Looks like it'll be for sale.

    Barry,

    I agree but it was just put together with bits I had to see if it would be beneficial and it's not, in my house anyway.

    So the BMU is out, DIY multiplication is in.

  7. #7
    Join Date: Oct 2008

    Location: Glasgowshire

    Posts: 9,656
    I'm Gary.

    Default

    Mines is hardwired and my mains is shit...may be a factor.
    AC POWER
    Hardwired 10kVA balanced mains powering entire system
    AMPS
    Meridian 557 power Amp (Modded) / PS Audio BHK Preamp (Modded)
    SPEAKERS
    Wharfedale Evo 4.4
    DAC
    PS Audio Directstream (Modded)
    TURNTABLE
    Pro-Ject X8 balanced output via XLR / Ortofon Quintet Blue cartridge
    PHONOSTAGE
    Pro-Ject DS3 B balanced Input (TT and Phonostage powered by Pro-Ject Power box RS2 linear psu)
    DIGITAL
    OPPO 203 (Modded: Linear PSU, i2s output to Dac) - Roon Endpoint, HDMI input used for all things Streaming/ PS5 /AppleTV ... also good for movies apparently?
    MUSIC PLAYBACK
    Tweaked AP-Linux based Roon Server into Oppo 203 as Roon endpoint
    Ipad Roon Remote.
    Apple Music/ YouTube via AppleTV, fed to Dac via Oppo HDMI input/i2s output to Dac.
    SPEAKER CABLES
    Biwired: Duelund DCA10GA (Bass) Duelund DCA16GA (mid & treble) Duelund 12DCA used as jumpers (On
    "Blackcat Cable" Chris Sommivigo's advice - yup, even with biwire it sounds better - and it does)
    INTERCONNECTS
    All Balanced: Ghost+ recording studio XLR cables

  8. #8
    Bigman80 Guest

    Default

    Right, I take it back

    I've taken the SUT out and the phonostage and put the Vivant in with direct MC connection.

    Volume on full and the mains sounded horrific but NO hum. Dropped the BMU back in volume on full and voila, almost silent.

    So diagnosis is - Wizard phonostage needs a bit of help to dispel the hum and the SUT needs some position help.

    Sound with the BMU in is clean. Almost added a bit of depth and dimension.

  9. #9
    Join Date: Oct 2012

    Location: The Black Country

    Posts: 6,089
    I'm Alan.

    Default

    Way to go ....

    We'll try some fixes with the Wizard to see where it is lacking, could be that a resistive link to the chassis may be beneficial.

  10. #10
    Bigman80 Guest

    Default

    Right, Rothwell SUT back in with the Vivant and......... No hum, hiss or nasty sounds. SO.....it's the bloody Wizard phonostage.

+ Reply to Thread
Page 1 of 4 123 ... LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •