The Fairchild Ghost. Subwoofer project.

OK so another idea I had. If you look back at the original mobile Stroker 12....

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It had a rather nice big plate on the back. With stickers on. So, using modern techniques I want to make something similar. Annoyingly they did not have 5mm in the same gold, so I got an A3 sheet of that.

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I mean in gold. Obviously sold out. I also got a A3 sized sheet in black.

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Again in 3mm. Which will total 6mm or over (due to sheets never being exactly 3mm). This will be cut with a centre hole the size of the magnet plug OD, and then be the size of the magnet OD. Which I don't have access to as I am at home now. I will do that and machine them when I return.
 
Lost interest in your speaker....want to see more of Gary's lathe! ;) :D
Old-school operator of old-school lathe? Only assume as he's converted everything to imperial. I'll be impressed if he can hold the 5 tenths he's written. Not impossible but challenging.... usually unnecessarily so too.
You want to be careful where you're calling out threads in diagrams like that. If you call out M10x2mm it would mean a 2mm pitch to the thread rather than a threaded hole 2mm deep. Different enough in this case as to be obvious (although if Gary's attempting an M10x20, I want video!) but just so it doesn't bite you on another occasion.
 
Yes and yes. He retired 2 years ago now but his garage is like a dream man cave. Im not sure what lathe he has but he was the one who said your one was a toy. I do know it was made in 1974. He also has a mill (two iirc). His garage has a pit for working on cars where he built his own Lotus 7.

I did need to explain a few things as obs Im not an engineer.
 
ALXAndy said:
he has but he was the one who said your one was a toy.
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I'd like to say how offended I am....but...he's not wrong :) Old iron is (or at least can be) really good. Can also be had quite cheap...you just need the room. To be honest, the most impressive thing about the Chinese lathes and mills is how good they are....given that the deeper you dive, the more 'wrong' they are. The fact they've taken so many shortcuts and still come out with something acceptable is quite astonishing.
 
I do know that it was literally his job for his entire working life. Funny thing is that he said that his company was struggling to find young people willing to learn the art. Like they'd just quit after a week. Lazy little sods.
 
OK so last post for a while. Well, until I return to it. I decided to not use banana sockets. Speakon is tidier and IMO better as it locks in.

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One plug.

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M5 Ti plated bolts to hold the woofer in.

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This is needed to assemble the pole structure.

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And then to go from the amp to the speaker. I will lop one end off and fit the Speakon connector to it.

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I have also decided to give grill making a go. So I ordered this from Ali also (with the gold bolts).

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I will use magnets to hold it on.
 
Just make sure you really mean it when you apply that threadlocker. The only way that's coming off non-destructively is to heat it past 150°C....and I'm not sure your cone or one-of-a-kind spider is going to survive that! Would it not work with some medium strength that can still be removed (with some difficulty) with hand tools? Don't get me wrong, I'm all for over-kill (obviously!) but less so if it's going to bite me in the SpeakOn socket!

The SpeakOn's were always good for the touring stuff I was involved with. That or locking XLRs. Gotta love a good balanced line for now chirping every time someone got a text message! Although it's quite amusing when you can hear the football scores coming across louder than the local am-dram players.
 
RE the thread locker? Absolutely. RE the spider? That gets glued to the woofer. Meaning that the whole pole and bottom of the top clamp are then captive. IE if you didn't use your brain and undone the two m6 screws you're screwed, pun intended. So yeah even getting to anything under that spider is a cut out and recone. Given it will never be driven in anger it's fine. And besides, the original Stroker's pole was also held in with the same because if it comes loose it would be very dangerous. Some guy on Ebay found this out when reconing as he tried to remove it and it sheered off just above the thread. IE ruining it forever.

I just like the neatness of the Speakon tbh. But yeah the twist lock fit is also very safe. Plus it's bang tidy which I'm also trying for.
 
BTW just to note. I will be using blue locker in the top plate and grub screw. As those may need to come off one day...
 
OK so a little size crunching on a sheet. It seems I had plenty of material so I added in two internal braces (I think I can only fit one) and even a panel to make the front grill from. This will all save me cutting manually.



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And thus I designed my braces. Now obs they are not tank like because the cabinet is small and stout any way, and I don't want to have to do tons of belt sander work to aero the edges. I am hoping the mini router I bought may actually serve a purpose this time and not throw a bearing and destroy the whole cabinet lmao.



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Have added a 30mm hole saw to my wish list. No point ordering anything else now because I can't go over for another 9 days harumph.
 
This changes everything.

OK so I have an amp for the sub. Complete and should all be working. However, at the beginning I did mention that at some point I wanted to get a proper monoblock. Like, a proper hifi one. The problem, as I explained it, was that the amp I do have out of the old Earthquake sub has all of the bass controls and so on. All of the things you need to crossover the sub. Obviously a hifi monoblock just puts out a flat signal..

So I went back to my roots and started looking for active crossovers. I could not find any. Well, I could, but only from the 90s. For some reason they are no longer being used. What I did not know is that these days people all use DSPs. Problem is most of them are horrifically expensive. Especially if you just want to control one sub.

Then I stumbled across this.

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Its only downside is that it does not have bluetooth and an app. However, at 62 pounds delivered it was an absolute bargain. I doubt I will use it for a good while, but it will be there when I do find the amp I really want (and can afford, which will be october time after my holiday). I may even get a 100 amp power supply and use a Taramps monoblock.
 
That is some serious dedication to audio! Can't wait to see the finished product. How much difference does the choice of material affect the sound in this build?
 
cavemanoc said:
That is some serious dedication to audio! Can't wait to see the finished product. How much difference does the choice of material affect the sound in this build?
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I will be using expensive MDF. There is absolutely no reason to do so. I only want it because it finishes better. The main point of it is that what I will be using is hydrophobic. So water proof. But it does finish better. The biggest part is bracing and making your cabinet stiff (fnarr).

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The green inner core is, well, green. It's like that because it has been treated. The biggest thing for me is that on this type of MDF the outer shell is harder. Thus sands better and you get a better finish. This is important because I am using a gloss wrap that will show everything if it is not perfect.

I mean here, as an example.

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It paints and finishes pretty much flawlessly.
 
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Ahhh, the Medite MR that I should have used for my MFP top instead of the cheaper stuff :D
I have a feeling that Taramps box is the kind of device that will play a trill through the speaker when it's powered up. Can you make the it the THX drop? ....or was the plan to NOT get the neighbours to have you evicted?! ;) :D
 
Cenedd said:
Ahhh, the Medite MR that I should have used for my MFP top instead of the cheaper stuff :D
I have a feeling that Taramps box is the kind of device that will play a trill through the speaker when it's powered up. Can you make the it the THX drop? ....or was the plan to NOT get the neighbours to have you evicted?! ;) :D
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Wot you didn't get the fire proof stuff for 400 quid a sheet? cheap boy !
 
Nah, I really wanted the black Valchromat stuff....but it's £380 plus delivery. Even the cheaper brands (eg Fibralux or unbranded) are £280 plus delivery for a 1200x2440x19mm sheet. Looks pretty though - it's black (or whatever colour) all the way through so if you cut into it or engrave it, it's still black.
 
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It is way cheaper than last time. I guess prices are settling. Just asked for the invoice and will get that paid.
 
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