The Fairchild Ghost. Subwoofer project.

OK so there is another tiny update.

I have been looking into grills using magnets. I will need a few, as the frame will be quite heavy. Any way, I decided on 15mm magnets.

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The problem was how to put them into the wood. My plan is to fit them, use epoxy as a filler around any edges (so they are flush mounted) and then basically paint and vinyl over the top to make them (hopefully) invisible. Took me a while to find this. I was beginning to think I would have to try and use a mill bit like I did when installing the feet on the last sub but it seems such a bit does exist.

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So that was cool. It's amazing how these small purchases all add up tbh. That said, I have never ever complained about buying any tool no matter how little I may use it.
 
Definitely a Forstner but and not as unusual a size as I first thought.... being my set starts at 15mm.
You might have been able to get away with a spade bit (the flat ones) if cheap was the primary concern and you either weren't going that deep, didn't mind the point breaking all the way through or could grind the point back a bit. An endmills would (or at least SHOULD) have been more expensive and also has no means of keeping it still to start if you're hand drilling. Drill press or mill, not a problem.

You joke about the router but he could put it in the CNC and interpolate (basically mill round in a circle) some holes larger than the endmill. Just depends if the panel will even vaguely fit on the bed!
 
Spade bits have a point that would go all the way through the sheet. More filling and sanding work.

I've bought a mono block. Came up on Ebay from Peter Tyson. Cost me £335 which was epic cheap tbh. I'll post pics later.

As for routers? Nah. If you saw the last project and how a bearing fell off and destroyed the whole cabinet you'll see why lol.

I am going to try and use a roundover bit on the braces though.

OK just taking a breather after putting one of the 7.1 side sockets in the wall. Got a bit warm (it's like an oven in here at the best of times).

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That's what I got. I saw one on a site I have bought from before used for 599 quid. Peter Tyson had it (they are all refurb btw not sure they make them now) for 399. Then they had one of those coupons so yeah, 335 delivered. Which is cheap enough for me to actually want to do it now.

You'll probably have noticed that I am a huge supporter of just doing things properly. I just didn't think I would get it so cheap that I could do it now. And yeah, 335 quid is a lot of money but the RRP on it was 1200. Hence why they go for around half that. It's absolutely pristine too.
 
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Is that just a forstner bit? If not, would a forstner bit not have worked?

Can always go full overkill and use a router!

Heh, everything is easy when you know what it's called !! :D

I don't have a plunge router btw. I got this the last time I built a sub box..

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And tbh it was actually really good. It was the roundover bit that failed. The bearing came off, I did not notice until it was far too late and I had eaten a lot of wood lmao. But yeah, destroyed the cabinet I got free with a woofer and I then had to build an entire new box. Which was bad. So I am kinda apprehensive about using it again.

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OK, so one monoblock. It is UK made by Cyrus (Mission). It will do 150w RMS into 8 ohm, and 240 into 4. Not sure I need more than 150 tbh but if I do I will look into dummy loads.



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Funny thing is I always thought the shells on these were plastic. Mostly because of the shape etc. Turns out they are moulded alloy, and thus it weighs an absolute ton.



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Amazingly it is actually very difficult finding single monoblocks for sale. They are usually always in pairs if they are used. Which is annoying, given I want to power a sub. So yeah, just another reason to grab it tbh.



I've also made up the cables from wall to DSP and DSP to amp.



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Which was just mainly using up all of the random spares I have collected over the years.

Edit. It has annoying connectors on the back (the amp). So I got these.

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Going back to the amp.

I watch a guy on the tube and he has an amp dyno. Well yesterday he uploaded a video of a 15 inch cinema sub. He took the amp out and its identical to the one I was going to use. It said it was 150w (same) and although the two boards on it were oriented differently it was identical.

It made 46w at 8 ohms.

So I feel completely redeemed tbh. I'd have been so disappointed with the sub thinking it was bad.
 
Maybe that 150W PMP (that Peak Marketing Pretense) !

Even up to clipping it was still absolutely pathetic. Even at 2 ohms (it would blow up pretty fast) it didn't manage much.


Aside from the fact it was probably even cheaper than mine to make (it does not have a power socket, just a wire going in) it is still absolutely pathetic. I am surprised at Dayton Audio tbh. They usually don't lie much at all.

Edit. At 8 ohms it was actually 44 watts.

Like I said, I would have sworn the sub itself was bad.
 
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OK so maybe the last update until I get going on Weds. I think I have found the solution for the Forstner bit. This has taken hours of research, as most of them are built like rubbish and are just not up to the job or built well enough to do the said job, but...

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It's not the financial side of things preventing me from buying an actual drill press. It's the logistics. I have nowhere permanent to set one up and thus I would be forever moving it. And, if you know about drill presses you would know they ain't light. As such I wanted one of those ^ but as I said most of them are poorly reviewed due to being wobbly, flimsy and not very accurate. As it happens it's 35 quid. Which is more than acceptable, given I bought a workhorse drill after blowing my old one up (I didn't want to trash my Bosch Pro cordless).

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So yeah, easy to take apart and smaller and lighter to stash. I am going to be buying a cheapo workbench for this, so I will bolt it to that in order to use it. Another thing I have in my list is this.

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Because as I mentioned somewhere (I need to find it) I do have this.

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And I would like to actually get some use out of it. I even have the correct cutting bits to use with it, and would actually like a nice round circle lol. Well, two, as the grill needs one too. The grill needs a "as close to perfect as humanly possible" hole given it is how the woofer will take the weight of said grill. Hard to explain but yeah. The magnets will not hold the weight, they will just hold it in place so the rim of the woofer takes the weight.
 
I get the nostalgia part of the stroker sub but as with everything technology has moved on. The subs made these days from the likes of sundown audio and re audio (the xxx) are in a whole different league to what cervin Vega produced. Who not use one of those?
I'm a car audio guy and can see how things have gotten better over the years, only reason I'd run older tech is if I have it lying around or get it cheap.
 
I get the nostalgia part of the stroker sub but as with everything technology has moved on. The subs made these days from the likes of sundown audio and re audio (the xxx) are in a whole different league to what cervin Vega produced. Who not use one of those?
I'm a car audio guy and can see how things have gotten better over the years, only reason I'd run older tech is if I have it lying around or get it cheap.

It depends what you mean by "better".

I already have a lolsub. Its on page one. Vibe Black Air 15. I don't like it. Does it make a lot of bass? Yes. Is it in that case better than subs of the past? Also yes. But define better. More bass? Yes. More accurate detailed tighter bass? No.

20 year old me would absolutely agree with you. But 52 year old me is now annoyed that in order to hear this lovely detailed controlled bass he has to risk cracking his ceiling.

You're forgetting that somewhere among all of this is audio quality. Are you really telling me that Sundown are an SQ company? Lmao come on man.

I suppose JL would come about the closest for me for SQ and bass. But Im not after one of their low end less XMAX speakers.

You also need to bear in mind that I listen to music. Not sit in a car blasting my internal organs in attempt to reorganise them.

That is why the Stroker was, and is still, so good. Its tight, controlled and accurate and could put out a lot of bass and take a lot of power.

Does it look like a plate of jelly being haplessly wobbled around? No, but I've already got that and Im not a fan.
 
Enclosure makes a big difference, crap sub in good enclosure can be made to sound better than a good sub in a crap enclosure.

There are sq subs out there these days, iv seen mention of gladen audio and b2 audio and few others.
Now square subs I'm not so sure of
 
Enclosure makes a big difference, crap sub in good enclosure can be made to sound better than a good sub in a crap enclosure.

There are sq subs out there these days, iv seen mention of gladen audio and b2 audio and few others.
Now square subs I'm not so sure of
Solobaric etc. I had a 12 and I hated it. Felt like I was being kicked in the back.

For me the best SQ subs back in the day were Image Dynamics. My cousin had a ID 12 with some Dynaudio mids and it sounded amazing.

That said as brutal as the Stroker could be it also sounds amazing. Its control is on another level.

But yeah dude the hint should have been when I said I want to go from a 30hz box to a 42hz.

Im one of those weird guys who is half audiophile and half bass head. The only reason I even need a sub is because I am so obsessed with SQ I bought studio measuring gear. Its also not a car either.
 
Solobaric etc. I had a 12 and I hated it. Felt like I was being kicked in the back.

For me the best SQ subs back in the day were Image Dynamics. My cousin had a ID 12 with some Dynaudio mids and it sounded amazing.

That said as brutal as the Stroker could be it also sounds amazing. Its control is on another level.

But yeah dude the hint should have been when I said I want to go from a 30hz box to a 42hz.

Im one of those weird guys who is half audiophile and half bass head. The only reason I even need a sub is because I am so obsessed with SQ I bought studio measuring gear. Its also not a car either.

30hz? :confused: my triple FR is down to about 10hz.
 
It'll be the frequency the cabinet is tuned to, the frequency for which it's most optimised/efficient rather than the lowest frequency it can produce at all. Am I right? What do I win?! ;-D
 
It'll be the frequency the cabinet is tuned to, the frequency for which it's most optimised/efficient rather than the lowest frequency it can produce at all. Am I right? What do I win?! ;-D

I dont think he understands what fs is and that it's not the same as cabinet/port tuning and so on.

Most if not all modern subwoofers will play down to 10hz. My existing sub included. FS is the free air resonance of the woofer without a box and box and port tuning are also different.

And you're correct, the box and port tuning are selected on your tuning preference and etc. You want the sub to come in where your other speakers stop.

I have never seen anyone silly enough to even try and build a 10hz enclosure. Mostly because you can't even really hear 10hz (you feel it) and that no music I've ever listened to goes down that deep. IIRC the frequency used in competition is 40hz. Or they may have different categories.

I think someone told him that what he has is like, super special and unobtanium and he bought it.

Righto that's probably the last time I'll have enough time to explain that for a while. Magnet clamp does not fit as it seems the hole in the centre is tapered ffs so that part will have to be sent back and trimmed a tad.
 
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