Dear Shockpersons
I have a field coil speaker that came to me with a jukebox amp. It has been previously reconed by persons unknown and works, but doesn't have much high-end reproduction. It is currently running off the amp's B+ at ~260VDC as per the schematic, but is not required as a choke in that circuit so I am able to compare it to another 12" speaker - a Weber 12F150 in the same 2x12 cab, and a Weber 12A150 in a single 12" cab. Even as guitar-specific speakers, they are much more full range.
Questions - can the frequency response of the field coil speaker be manipulated by adjusting the applied voltage - ie if I lower the supply, the speaker will reproduce more top end?
Can the electrodynamic magnet set-up degrade over time? Or does a partial short in the coil possibly cause this, could this be rewound?
Is it possible that it has been reconed in a way that cuts off the top end?
It's not a subtle thing - I used the amp and speaker as a shop mono music player for a while and its night and day with the change in speakers. The jukebox would have wanted a full range response to reproduce records, and the amp has controls to attenuate treble and bass, so I'm thinking it can't always have been like that.
Thanks in advance for sharing any experience with these
I have a field coil speaker that came to me with a jukebox amp. It has been previously reconed by persons unknown and works, but doesn't have much high-end reproduction. It is currently running off the amp's B+ at ~260VDC as per the schematic, but is not required as a choke in that circuit so I am able to compare it to another 12" speaker - a Weber 12F150 in the same 2x12 cab, and a Weber 12A150 in a single 12" cab. Even as guitar-specific speakers, they are much more full range.
Questions - can the frequency response of the field coil speaker be manipulated by adjusting the applied voltage - ie if I lower the supply, the speaker will reproduce more top end?
Can the electrodynamic magnet set-up degrade over time? Or does a partial short in the coil possibly cause this, could this be rewound?
Is it possible that it has been reconed in a way that cuts off the top end?
It's not a subtle thing - I used the amp and speaker as a shop mono music player for a while and its night and day with the change in speakers. The jukebox would have wanted a full range response to reproduce records, and the amp has controls to attenuate treble and bass, so I'm thinking it can't always have been like that.
Thanks in advance for sharing any experience with these
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