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squinancy · 6th May 2019, 9:22 am

Hello Everyone,

I don't know how to put it in words, maybe I should upload an MP3 recording. My Lady Margaret has been working well for years. It underwent an o/p transformer replacement. All iffy caps changed, LT & HT batteries supplying the right current and voltage.

But, at slightly higher volumes (not yet full) and certain sound frequencies - perhaps the frequency range of an average female voice - the speaker begins to resonate and produce a sound that is best described as screws loudly rattling at the bottom of a tin bucket. As if something was loose, torn or broken in or around the speaker.
Only affects mid-range sounds, bass and high treble OK.

There is nothing wrong with the speaker by the look of it, the paper cone is intact, healthy, solid to touch. I wonder what this could be. Any suggestions, please? Changing the speaker is quite a hassle in a CN429.

6th May 2019, 9:22 am	#1
squinancy Retired Dormant Member Join Date: Aug 2007 Location: New Malden, London, UK. Posts: 70	Vidor CN429 Lady Margaret rattling sound Hello Everyone, I don't know how to put it in words, maybe I should upload an MP3 recording. My Lady Margaret has been working well for years. It underwent an o/p transformer replacement. All iffy caps changed, LT & HT batteries supplying the right current and voltage. But, at slightly higher volumes (not yet full) and certain sound frequencies - perhaps the frequency range of an average female voice - the speaker begins to resonate and produce a sound that is best described as screws loudly rattling at the bottom of a tin bucket. As if something was loose, torn or broken in or around the speaker. Only affects mid-range sounds, bass and high treble OK. There is nothing wrong with the speaker by the look of it, the paper cone is intact, healthy, solid to touch. I wonder what this could be. Any suggestions, please? Changing the speaker is quite a hassle in a CN429.