+ Reply to Thread
Page 2 of 6 FirstFirst 1234 ... LastLast
Results 11 to 20 of 51

Thread: New set up annoying buzz / hum I can't get to the bottom of......

  1. #11
    Join Date: Mar 2008

    Location: Galashiels

    Posts: 13,669
    I'm inthescottishmafia.

    Default

    Yes worth doing, means you can isolate it to a source or the amp, we can then proceed from there.
    “Music has always been a matter of energy to me, a question of fuel. Sentimental people call it inspiration, but what they really mean is fuel. I have always needed fuel. I am a serious consumer. On some nights I still believe that a car with the gas needle on empty can run about fifty more miles if you have the right music very loud on the radio”

    Hunter S Thompson

  2. #12
    Join Date: Jan 2019

    Location: Cambridgeshire, United Kingdom

    Posts: 904
    I'm Russell.

    Default

    I've now uploaded some video of the hum & cones flapping on both my La Scala's & Naim Speakers (easier to see on the Naim's):

    https://www.youtube.com/watch?v=9JBn8A8WFzU

    https://www.youtube.com/watch?v=j9DtfjsJziM

  3. #13
    Join Date: Feb 2013

    Location: W Lothian

    Posts: 99,005
    I'm Grant.

    Default

    could be dc from amp. can you try another amp?
    Regards,
    Grant .... ؠ ......Don't be such a big girl's blouse

    I've said it before and I'll say it again: democracy simply-doesn't-work
    .... ..... ...... ...... ................... ..... ..... ..... ..... .....
    FIIO K7 BT, M11 PLUS, BTR7, KA5 - OPPO BDP-103D - PANASONIC UB450 - PANASONIC 4K ULTRA HD TV - PIXEL 6 - AVANTREE LR BLUETOOTH - 2* X600 SOUNDCORE - HEADPHONES INCLUDE, FIIO, NURAPHONES', FOCAL, OPPO, BOSE, CAMBRIDGE, BOWER & WILKINS, DEVIALET, MARSHALL, SONY, MITCHELL & JOHNSTON - 2*ZBOOK'S- MERCURY BD ROM, ROON, QOBUZ, TIDAL, PLEX, CYBERLINK, JRIVER - MULTI HDD'S -

    Oh my god! There's nothing wrong with the bidet is there?

    “Nothing discloses real character like the use of power. It is easy for the weak to be gentle. Most people can bear adversity. But if you wish to know what a man really is, give him power. This is the supreme test. It is the glory of Lincoln that, having almost absolute power, he never abused it, except on the side of mercy".

    “You see these dictators on their pedestals, surrounded by the bayonets of their soldiers and the truncheons of their police ... yet in their hearts there is unspoken fear. They are afraid of words and thoughts: words spoken abroad, thoughts stirring at home -- all the more powerful because forbidden -- terrify them. A little mouse of thought appears in the room, and even the mightiest potentates are thrown into panic.”

    "You don't have free will. You have the appearance of free will.”

    “There's a war out there, old friend. A world war. And it's not about who's got the most bullets. It's about who controls the information. What we see and hear, how we work, what we think... it's all about the information!”


    ***SMILE, BE HAPPY***

  4. #14
    Join Date: Mar 2008

    Location: Galashiels

    Posts: 13,669
    I'm inthescottishmafia.

    Default

    Also try moving the amp around, see if the hum changes/goes. Could be picking up RF from another component.
    “Music has always been a matter of energy to me, a question of fuel. Sentimental people call it inspiration, but what they really mean is fuel. I have always needed fuel. I am a serious consumer. On some nights I still believe that a car with the gas needle on empty can run about fifty more miles if you have the right music very loud on the radio”

    Hunter S Thompson

  5. #15
    Join Date: Apr 2009

    Location: Near Saffron Walden, Essex

    Posts: 7,087
    I'm Dave.

    Default

    Quote Originally Posted by Weeman1973 View Post
    Thanks Dave - kit is Gate Valve Pre Amp, Croft 5C Valve Amp, WML La Scala Speakers.

    I've disconnected everything except PowerAmp to La Scala Speakers - hum is still there but very feint.

    If I connect any leads at all to the Input on the Power Amp, the hum gets louder (even if not connected to Pre amp at the other end).

    If I then connect the Pre & Power Amps together, hum gets louder - even if Pre is not switched on.

    Louder still once Pre is switched on & then louder again when using the MM Phono input on the Gate pre.

    Seems to me like an issue with the Power amp?
    Seems to me more like the pre. The power-amp will usually produce a very slight hum through sensitive speakers, audible close up to the speakers, with nothing connected.

    If the hum gets louder with pre connected and louder still with the pre switched on, it is likely to be the pre. Also, that thing with the volume control is worrying.

  6. #16
    Join Date: Jan 2019

    Location: Cambridgeshire, United Kingdom

    Posts: 904
    I'm Russell.

    Default

    After lots of fettling, I think I can narrow it down to the Power Amp...

    I set my Croft Integrated (active pre & power sections) to the speakers & powered up with nothing connected - very low hum but only if i put my ears very close to speakers - this hum doesn't go up & down with volume.

    Connected my X40 Streamer and powered up, all is good no extra hum there.

    I then connected a SS Power Amp (Cympol CPA3) to my speakers with no source connected to that - absolute silence. Same when I use my X40 as the pre so all is good there.

    I then connected the Gate Pre Amp to the Cymbol PA & used the X40 as a source then. With nothing playing there is silence except when I tun the volume on the Gate up & down - no hum but a sort of white noise sound but again very low. When playing a source this way there's no hum either.

    So I think it must be the PA - trouble is how do I solve it?

  7. #17
    Join Date: Feb 2013

    Location: W Lothian

    Posts: 99,005
    I'm Grant.

    Default

    I would get it checked out by an engineer.. may be the start of dc getting onto the speakers, or it could be something else. You have said your not comfortable with electrics so getting it checked by someone that is is important in case it gets worse.
    Regards,
    Grant .... ؠ ......Don't be such a big girl's blouse

    I've said it before and I'll say it again: democracy simply-doesn't-work
    .... ..... ...... ...... ................... ..... ..... ..... ..... .....
    FIIO K7 BT, M11 PLUS, BTR7, KA5 - OPPO BDP-103D - PANASONIC UB450 - PANASONIC 4K ULTRA HD TV - PIXEL 6 - AVANTREE LR BLUETOOTH - 2* X600 SOUNDCORE - HEADPHONES INCLUDE, FIIO, NURAPHONES', FOCAL, OPPO, BOSE, CAMBRIDGE, BOWER & WILKINS, DEVIALET, MARSHALL, SONY, MITCHELL & JOHNSTON - 2*ZBOOK'S- MERCURY BD ROM, ROON, QOBUZ, TIDAL, PLEX, CYBERLINK, JRIVER - MULTI HDD'S -

    Oh my god! There's nothing wrong with the bidet is there?

    “Nothing discloses real character like the use of power. It is easy for the weak to be gentle. Most people can bear adversity. But if you wish to know what a man really is, give him power. This is the supreme test. It is the glory of Lincoln that, having almost absolute power, he never abused it, except on the side of mercy".

    “You see these dictators on their pedestals, surrounded by the bayonets of their soldiers and the truncheons of their police ... yet in their hearts there is unspoken fear. They are afraid of words and thoughts: words spoken abroad, thoughts stirring at home -- all the more powerful because forbidden -- terrify them. A little mouse of thought appears in the room, and even the mightiest potentates are thrown into panic.”

    "You don't have free will. You have the appearance of free will.”

    “There's a war out there, old friend. A world war. And it's not about who's got the most bullets. It's about who controls the information. What we see and hear, how we work, what we think... it's all about the information!”


    ***SMILE, BE HAPPY***

  8. #18
    Join Date: Jan 2019

    Location: Cambridgeshire, United Kingdom

    Posts: 904
    I'm Russell.

    Default

    Quote Originally Posted by struth View Post
    I would get it checked out by an engineer.. may be the start of dc getting onto the speakers, or it could be something else. You have said your not comfortable with electrics so getting it checked by someone that is is important in case it gets worse.
    Think I will thanks Grant.

    It was originally Alan's (Firebottle) & he said he noticed nothing untoward when he had it.

    Any recommendations of who I could see with it (I'm in Cambridgeshire). Thanks.

  9. #19
    Join Date: Feb 2013

    Location: W Lothian

    Posts: 99,005
    I'm Grant.

    Default

    the amp could still be ok, and it is something that is affecting that amp but not your others, but getting it checked and either fixed or cleared of having a fault is the first step. Until that is done its difficult to be sure about anything else.
    Alas everything is not always straightforward on these occasions
    Regards,
    Grant .... ؠ ......Don't be such a big girl's blouse

    I've said it before and I'll say it again: democracy simply-doesn't-work
    .... ..... ...... ...... ................... ..... ..... ..... ..... .....
    FIIO K7 BT, M11 PLUS, BTR7, KA5 - OPPO BDP-103D - PANASONIC UB450 - PANASONIC 4K ULTRA HD TV - PIXEL 6 - AVANTREE LR BLUETOOTH - 2* X600 SOUNDCORE - HEADPHONES INCLUDE, FIIO, NURAPHONES', FOCAL, OPPO, BOSE, CAMBRIDGE, BOWER & WILKINS, DEVIALET, MARSHALL, SONY, MITCHELL & JOHNSTON - 2*ZBOOK'S- MERCURY BD ROM, ROON, QOBUZ, TIDAL, PLEX, CYBERLINK, JRIVER - MULTI HDD'S -

    Oh my god! There's nothing wrong with the bidet is there?

    “Nothing discloses real character like the use of power. It is easy for the weak to be gentle. Most people can bear adversity. But if you wish to know what a man really is, give him power. This is the supreme test. It is the glory of Lincoln that, having almost absolute power, he never abused it, except on the side of mercy".

    “You see these dictators on their pedestals, surrounded by the bayonets of their soldiers and the truncheons of their police ... yet in their hearts there is unspoken fear. They are afraid of words and thoughts: words spoken abroad, thoughts stirring at home -- all the more powerful because forbidden -- terrify them. A little mouse of thought appears in the room, and even the mightiest potentates are thrown into panic.”

    "You don't have free will. You have the appearance of free will.”

    “There's a war out there, old friend. A world war. And it's not about who's got the most bullets. It's about who controls the information. What we see and hear, how we work, what we think... it's all about the information!”


    ***SMILE, BE HAPPY***

  10. #20
    Join Date: Sep 2013

    Location: North Island New Zealand

    Posts: 1,757
    I'm Chris.

    Default

    The usual cause of hum like this in a unbalanced audio system is a cable with a ground connection missing or broken - like a RCA cable looking OK externally but actually having a
    broken connection for its ground. Suggest disconnect input cables to power amp... does hum disappear ? If Yes then fault is a input cable.requiring repair or replacement.

    Opto coupling with a LDR attenuator enables total silence for audio attenuation- which is a amazing feature of LDR's that other preamps cannot match.

+ Reply to Thread
Page 2 of 6 FirstFirst 1234 ... 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
  •