I have a Philips 2514 radio Which has finally been brought to life. I have a 1925 BTH horn Speaker which apart from its size sounds pretty bad. The radio on Hi Z phones is OK, well it's just acceptable I was wondering how I might make a Hi Z speaker. The Present O/P transformer is High in High out. I don't want to use a another transformer on the O/P with a 4/8 Ohm speaker. I was thinking more along the lines of a coil on a ferrite former. The moving part of the speaker would be a rigid disk. the centre of which would be located by tiny neodym magnets surrounded by other neodym magnets in concentric rings the two extreme rings would be the same polarity to locate the x/y axis centrally while another opposite polarity ring would keep the disk centred.
Max power is probably about 0.5W.
Any ideas suggestions welcom.
M
DIY High Z Speaker.
#2 Re: DIY High Z Speaker.
Just been looking at Audio exciters, If the coil no longer moves because it is attached to the sound surface and is the magnet assy that is moving then this opens up a whole load of possibilities.
#3 Re: DIY High Z Speaker.
I have a new old stock phillips 800ohm 8" driver I belive they are quite collectable I
The tube manual is quite like a telephone book. The number of it perfect. It is useful to make it possible to speak with a girl. But we can't see her beautiful face from the telephone number
#4 Re: DIY High Z Speaker.
Thanks Steve,
Here the Z is 2K plus, there is not a lot of power to play with. The DC resistance of the O/P transformer appears to step up towards the speaker. Running the phones 2K and touching the terminals you get quite a tingle. I will read up on Philips 800 ohm speakers and see what the resistance and other specs are. I think the recomended speaker was 2k and it was 16" in diameter made from bakelite, it was an inverted cone if I remember correctly, In good nick they fetch about £150, too much for me. Thanks again, catch up in a day or two.
cheers
M
Here the Z is 2K plus, there is not a lot of power to play with. The DC resistance of the O/P transformer appears to step up towards the speaker. Running the phones 2K and touching the terminals you get quite a tingle. I will read up on Philips 800 ohm speakers and see what the resistance and other specs are. I think the recomended speaker was 2k and it was 16" in diameter made from bakelite, it was an inverted cone if I remember correctly, In good nick they fetch about £150, too much for me. Thanks again, catch up in a day or two.
cheers
M
#5 Re: DIY High Z Speaker.
I ran a few tests with different loads yesterday and it is definitely better with speakers etc over 2k. The secondary resistance of the O/P transformer is just under 1K. Setting up the regen to howl the Audio output V peaks at around a 3.5K load so I reckon 2k is probably where the most power is transferred.
Thanks for your offer, Maybe I can find a busted / cracked Bakelite one cheap.
Cheers
M
Thanks for your offer, Maybe I can find a busted / cracked Bakelite one cheap.
Cheers
M