The Fairchild Ghost. Subwoofer project.
- Thread starter ALXAndy
- Start date
OK so this was terrifying. One slip and it is game over. Also, one crumb down that coil gap and it is also game over. I cut out the dust cap with a scalpel and put a blu tak sausage around the coil gap to stop anything falling in.
And then used a plastic tyre lever with some gentle taps from a plastic hammer.
I have now designed the clamp in piece that will hold the centre pole. When I remove all of the measurements I will bung up a pic of that.
And then used a plastic tyre lever with some gentle taps from a plastic hammer.
I have now designed the clamp in piece that will hold the centre pole. When I remove all of the measurements I will bung up a pic of that.
OK so one thing I don't have and don't really want is the brass plate with the CV logo on.
So I designed my own and am machining it now.
This is one of three pieces I am going to machine. The other two double in machining time each time. So the next one? two hours. The last one? four hours lol.
So I designed my own and am machining it now.
This is one of three pieces I am going to machine. The other two double in machining time each time. So the next one? two hours. The last one? four hours lol.
I spent about an hour 3 weeks ago writing you an email. So either you missed it, didn't get it, or ignored it. Was kinda hoping it wasn't the latter. About 10 days after that I asked Gary in Dorset so he is doing it. I've just had no time for me at all. Ripped a cupboard down on the back kitchen wall, fixed wall, repaired loads of holes in it, sanded it then painted it and put shelves up. Last two days I have been cleaning up and putting the tools away I had out for a month so mum doesn't put them somewhere I will never find them.
My mum is the only woman I have ever met who has no respect for a man's tools. Probably because my dad died when I was 7 and she hasn't been with any one else. But yeah, even my aunt had to bring it up. Like don't F with a man's tools.
The last piece has now been drawn up (the stainless pole) and sent over. So I can go home and relax right? no chance. Got a PC with a dead pump in it FFS. Normally I would just leave that but I can't. I need to do a load of paper work and etc stuff for the council over council tax so yeah....
The last piece has now been drawn up (the stainless pole) and sent over. So I can go home and relax right? no chance. Got a PC with a dead pump in it FFS. Normally I would just leave that but I can't. I need to do a load of paper work and etc stuff for the council over council tax so yeah....
OK so the amp should now be fully functional.
I could not find 12v in there it is all mostly 20. So instead of buying resistors etc etc yada ya I just modded a 12v PSU and stuck it to the side to run the fan.
And test. Green = good lol.
I could not find 12v in there it is all mostly 20. So instead of buying resistors etc etc yada ya I just modded a 12v PSU and stuck it to the side to run the fan.
And test. Green = good lol.
20V DC? What you wanted was a buck convertor. 5-pack of 'em for just over a quid a piece at your favourite only delivery places. Just tell me you didn't do anything dodgy on the mains side - like wrap the wires round the plug terminals and stick 'em on with tape! 
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im liking this 
good effort
at some point i might have to post up some of my speaker shenanigans from my previous life/profession
also nice seeing someone else with a similar adjacent interest in speakers and finding them in another hobby forum altogether
dunno if youv ever seen the speakerplans.com forum ive spent most of my adult life on and off of their lol
good effortat some point i might have to post up some of my speaker shenanigans from my previous life/profession
also nice seeing someone else with a similar adjacent interest in speakers and finding them in another hobby forum altogether
dunno if youv ever seen the speakerplans.com forum ive spent most of my adult life on and off of their lol
20V DC? What you wanted was a buck convertor. 5-pack of 'em for just over a quid a piece at your favourite only delivery places. Just tell me you didn't do anything dodgy on the mains side - like wrap the wires round the plug terminals and stick 'em on with tape!
I would have had to order one and thus wait. I twisted off the 3 pin UK plug part and soldered from the pins sticking out onto wires, that feed from the 240v socket. So essentially it is the same thing really.
im liking this
at some point i might have to post up some of my speaker shenanigans from my previous life/profession
also nice seeing someone else with a similar adjacent interest in speakers and finding them in another hobby forum altogether
dunno if youv ever seen the speakerplans.com forum ive spent most of my adult life on and off of their lol
Sounds awesome dude. Oddly enough at that time I worked for Rogers UK. So when I was working it was all speakers, then at home it was more of the same lol.
I also forgot to say. I added a fan (obs). In the original Earthquake enclosure it was ported. So that would feed it air. So just to add belts and braces I put a fan in the side blowing directly over the actual amp part and the transistors. That way if it gets hot in here it won't simultaneously combust lol. Simple 80mm Noctua jobby and now I have a nice shiny new 80mm hole saw
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Associate
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yeah the old cerwin earthquake and its derivatives are still used a fair bit for dance and electronic music type events as it goes
usually in a big enough stack to get the required mouth area in an open space blah blah
always wanted to install heatpipes and big finned heatsinks with some noctua industrials on the back of the cabs to get the coil temps down and thus lower power compression [and also stop me from burning out voice coils lol admittedly im usually fairly sensible on limiting etc lol]
anyway looking forward to seeing this progress
making me seriously consider getting a tapped horn/ transmission line or something similar to play down low low under a pair of some old mordaunt short bookshelf speakers ive got a pair of behind the sofa but i need to concentrate on the music production gear more than the annoying the missus/neighbours gear lol
ported horns are also another interesting one lol
usually in a big enough stack to get the required mouth area in an open space blah blah
always wanted to install heatpipes and big finned heatsinks with some noctua industrials on the back of the cabs to get the coil temps down and thus lower power compression [and also stop me from burning out voice coils lol admittedly im usually fairly sensible on limiting etc lol]
anyway looking forward to seeing this progress
making me seriously consider getting a tapped horn/ transmission line or something similar to play down low low under a pair of some old mordaunt short bookshelf speakers ive got a pair of behind the sofa but i need to concentrate on the music production gear more than the annoying the missus/neighbours gear lol
ported horns are also another interesting one lol
Gene was obsessed with horn loading and so on tbh. IE, throwing that sound as far as you could. You know dude it is actually reallllllly weird you mention the coil temps..... That was the achilles heel with the folded horn. The woofer occupies a tiny sealed space inside with no way to breathe. That is how I first met John lmfao. Because I blew mine three times in the end. That was also how I found out about the Fane thing, and therefore he only had to send me coils and spiders. The rest I could get locally in the UK, without getting interfered with by Customs. But yeah I spoke to the guy I sold it to about 2 years after the fact and they used it for a rave and after about 40 hours it blew.
Man today was a good day !. I'm not an engineer but I think I was in my previous life lol. My friend sent this over earlier. Looks like our "beef it up" method wasn't a terrible idea tbh.
Someone also sent me the original patent from the 80s. Which was super cool. I used to have a pile of stuff about 4 inches thick that John sent me over the years. Sadly it all got lost during my first divorce. My wife decided she wasn't in it any more about 2 weeks before our lease was due to expire and just left. Meaning I had no time, and lots of things that meant a lot to me got lost forever. Heart breaking really. Still, one thing he will never take from me is the memories.
It looks like they did not want any one stealing their idea by working around it, so they made it both ways up lol. Not sure how the upside down approach would have worked as I would guess that never happened outside of maybe internal prototypes !
Man today was a good day !. I'm not an engineer but I think I was in my previous life lol. My friend sent this over earlier. Looks like our "beef it up" method wasn't a terrible idea tbh.
Someone also sent me the original patent from the 80s. Which was super cool. I used to have a pile of stuff about 4 inches thick that John sent me over the years. Sadly it all got lost during my first divorce. My wife decided she wasn't in it any more about 2 weeks before our lease was due to expire and just left. Meaning I had no time, and lots of things that meant a lot to me got lost forever. Heart breaking really. Still, one thing he will never take from me is the memories.
It looks like they did not want any one stealing their idea by working around it, so they made it both ways up lol. Not sure how the upside down approach would have worked as I would guess that never happened outside of maybe internal prototypes !
Found it. This is a fun read (if you are nerdy AF lmao)
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my thing for horn loading is mostly about efficiency*
the impedance of sound through different mediums is well different lol
so from the paper [cone] to the air there is a missmatch of impedance if oyu can to some degree make that conversion more efficient then well more efficiency [badly explained] also with higher [relatively] frquencies you can start using directivity to get mroe sound where you do want it and less where oyu dont [so efficiency/sensitivity well in this case efficiency]
anyway lol yeah big stacks go woooo woooo brrrrr brrrr basically lol
back on earth though lol
again love this project
*edit because i realise this is at least partially a lie im just a complete geek lol
the martin audio y bin would make an amusing pc setup id imagine [not lol]
the impedance of sound through different mediums is well different lol
so from the paper [cone] to the air there is a missmatch of impedance if oyu can to some degree make that conversion more efficient then well more efficiency [badly explained] also with higher [relatively] frquencies you can start using directivity to get mroe sound where you do want it and less where oyu dont [so efficiency/sensitivity well in this case efficiency]
anyway lol yeah big stacks go woooo woooo brrrrr brrrr basically lol
back on earth though lol
again love this project
*edit because i realise this is at least partially a lie im just a complete geek lol
the martin audio y bin would make an amusing pc setup id imagine [not lol]
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