'Popping' Dansette Conquest !!

[Skyman69]

Hi all
I've just re-capped the amp in my Dansette Conquest (single valve type) and now it's virtually hum free 👍🏻
But I've now noticed that it's now developed a 'pop' from the speakers when you walk near it or tap the cabinet !!
Obviously something is lose but I don't know what...could it be a faulty power switch or a bad valve ??

[Skyman69]

Can I also add that I've noticed that the speaker +ve terminal comes from the output transformers 'ground' connection as opposed to the blue wire !!
Is this correct or has someone been messing with it ?

['LIVEWIRE?']

The popping noise could be caused by bad connections between the valve(s) and socket(s). Cleaning the valve pins and the valveholder sockets may cure this. If the valveholder(s) are the McMurdo brand with fork shaped sockets (remove one carefully to see what I mean) these can become weak, leading to intermittent contact with the valve pins. Other things, e.g. drysolder joints, could also cause this fault. As to the speaker +ve terminal being grounded it could have been that way from new. IMHO when only one speaker is used, it's polarity is unimportant, unlike in 2 or 3 way speaker systems, where loss of bass response can be caused by incorrect phasing.

[Skyman69]

Great, thanks for that...I'll check the valve base.

[Boater Sam]

Are the 'speaker chassis grounded? You can get static building up on the metal work which 'grounds' out to the speech coil causing a pop and damage.

[Edward Huggins]

Just to add that this player uses two 7" x 4" speakers wired in parallel.

[Skyman69]

Originally Posted by Boater Sam

Are the 'speaker chassis grounded? You can get static building up on the metal work which 'grounds' out to the speech coil causing a pop and damage.

The +ve terminals of both speakers come from the ground post of the output transformer (which I don't think is right) !!
There's obviously no Earth though

[Skyman69]

Originally Posted by Edward Huggins

Just to add that this player uses two 7" x 4" speakers wired in parallel.

Correct 👍🏻

['LIVEWIRE?']

I didn't realise the Conquest had two speakers, but if they are wired in parallel, then the two positive terminals should be joined together, as should both negative terminals. If one was wired the opposite way round to the other, lack of bass due to out of phase connections would occur. If two speakers are wired in series then indeed the +ve terminal of one should be wired to the -ve terminal of the other.

[Station X]

Originally Posted by Edward Huggins

Just to add that this player uses two 7" x 4" speakers wired in parallel.

Originally Posted by 'LIVEWIRE?'

I didn't realise the Conquest had two speakers

I think that's pretty obvious from the picture in post #1