Jack 210

[gilmour]

Hi All,

So summers, upon us, meaning that my workshop (the front garden) is now useable again. It seems like an annual thing that I build some Bill FitzMaurice cabs each year - so I've decided to build a pair of Jack 210's for use with my covers band.

They will be built with Beta 10's and straight melded piezo arrays, a large part of my build has been dictated by the components I already have. :cool: I am cheap, the ideal would be Deltalite's and Crossfiring piezo arrays, but we all have to accept compromise.

I thought I'd keep a build diary as the Jack is a newer cab and not as well covered as some of the others.

At first glance of the plans the Jack seems a slightly more complex build to the Omni's I've built so far ([url="http://finnbass.com/showthread.php?t=3878"]O10.5[/url] & [url="http://basschat.co.uk/index.php?showtopic=11971"]O15TB[/url] [url="http://finnbass.com/showthread.php?t=4058"]comparison[/url]) but I don't feel to daunted, baby steps and all that.

Ohh and the other thing - I'm hoping to have them finished for Saturday after next :eek: as we have a show that's not paying very well so I don't really want to have to hire in a PA, and the O10.5s probably won't be quite enough. Fat chance. :cool:

Got back from the local B&Q with a suitably bowed pile of wood, full of voids and not quite cut to the sizes specified, perfect....


Pepper, was very interested in what was going on, he even woke up for a minute or two...


The more astute of you who have looked closely at the pic above will be asking "but surely for two cabs you only need four tops/bottoms and sides, why six Rob, why?"

Didn't spot it? me either, but go one look again...


The answer to the question you are now all asking is.... I have no f***ing idea, I spent about two hours trying to work out an efficent cut sheet, somehow failing to notice that I had made it so I can build three cabs ?!? :confused: Genius. I have a pair of Basslite S02010's lying around so could shove them in a cab, or pop them in my O10'5's and take my Beta 10's out. So I could viably make a third cab.

The way I see it I now have a few choices:
[b]1 [/b]- Forget it, just make 2
[b]2 [/b]- make three, but what am I gonna do with three 2x10's? you can't have two on one side and one on the other
[b]3 [/b]- split the spare and make two 110 then I can have three aside, leave the 110's tweeterless and have them on the bottom of the stack for a little more bottom end.
[b]4 [/b]- make the third box and leave it empty until such a time as I might need it.

I'm veering towards option 1 as I can't see me needing the other options.
Unlike any of the other BFM builds I've made the Jack has a Phase Baffle, meaning you need a little circle in front of the speakers on the baffle.

I like to work on a flat pack basis, I know it's not what Bill recommends but I just haven't got the space/facilities to cut, clamp, each piece, given that I have to do everything in the front garden. Any way here's the tops and Baffles, cut, predrilled and counter sunk. Annoyingly I found out half way through this process that the measurements on my meter rule were wrong so I had to start from scratch, grrr....

Flat Packed...


The Jack's call for a Phase plug in the baffle - meaning cutting a circle. I lost my compass, so had to improvise - I was so pleased with my solution I took a photo


I then proceeded to cut out the phase baffles. Slowly with the jigsaw, don't wanna cock this up. I'd hoped to have both finished by the end of the day, but the first one took a lot longer than I expected, and although it's light I don't want to piss off my neighbours with the noise. So I need to do the other tomorrow.

Finished Phase Baffle


I've also dug out my latex gloves so I can get busy with the PU, and full body cavity searches - gonna try double gloving this time.

Edited July 5, 2010 by gilmour

[Alien]

[quote name='gilmour' post='886727' date='Jul 5 2010, 10:00 PM']The way I see it I now have a few choices:
[b]1 [/b]- Forget it, just make 2
[b]2 [/b]- make three, but what am I gonna do with three 2x10's? you can't have two on one side and one on the other
[b]3 [/b]- split the spare and make two 110 then I can have three aside, leave the 110's tweeterless and have them on the bottom of the stack for a little more bottom end.
[b]4 [/b]- make the third box and leave it empty until such a time as I might need it.[/quote]

You missed out
[b]5[/b] - make three, put the 3rd one on your guitard's side of the stage, so he'll have no f**cking excuse for missing the changes

A

[gilmour]

[quote name='Alien' post='886868' date='Jul 5 2010, 11:38 PM']You missed out
[b]5[/b] - make three, put the 3rd one on your guitard's side of the stage, so he'll have no f**cking excuse for missing the changes

A[/quote]



I'm quite lucky in that our guitar player is happy to just be a wah monkey al night, as long as he gets one solo.

These are mostly going to be used for PA - although I'll definitely try them on bass, I couldn't resist it before...



It was waaaay tooooooo much.

[Subthumper]

[quote name='gilmour' post='886876' date='Jul 5 2010, 11:43 PM']

I'm quite lucky in that our guitar player is happy to just be a wah monkey al night, as long as he gets one solo.

These are mostly going to be used for PA - although I'll definitely try them on bass, I couldn't resist it before...



It was waaaay tooooooo much.[/quote]

Looks mighty fine. Slight change of subject but while we're on the subject of BFM cabs what happened to the omni 10's? The design is'nt on the BFM website anymore. Anyone got any idea's?
Good luck with the project, I still wanna do my own omni 15.....when I get time.
Cheers Just

[gilmour]

[quote name='Subthumper' post='886916' date='Jul 6 2010, 12:30 AM']Looks mighty fine. Slight change of subject but while we're on the subject of BFM cabs what happened to the omni 10's? The design is'nt on the BFM website anymore. Anyone got any idea's?
Good luck with the project, I still wanna do my own omni 15.....when I get time.
Cheers Just[/quote]

Not off topic at all.

The Jack 10's (which I'm building) replaced the Omni 10's

They are a very similar size and weight, but have improved bottom end.

From what I've read if you have omni 10's it probably not worth replacing them as they are still a mighty fine cab. I just went for these asI was building something new, and for PA it's useful that they can stand alone.

[gilmour]

Right managed to squeeze in a couple of hours this afternoon.

Firstly finished cutting out the second phase baffle - time consuming but enjoyable.

Next up I got on with cutting out my throat flat pack. There were a few moments with the circular saw (that thing terrifies me) but all in all went fairly smoothly. So I had my throat assembly flat pack.



The observational amongst you will notice random little clamps holding bits together. This is curtesy of the top quality warp and void free B&Q ply....


I'm quite pissed off about this. In the past I've noticed you guys criticise the B&Q ply, and I've never had problem with it. Ho hum I've come to far with this, I may as well nail it all together and hope that the vent duct's pull the throat sides together.

The Jack is very different to the Omni in this way. It has a 'Throat Assembly' where on the omni it fires straight into the short horn. Also this assembly has some clever vent duct running through it. God knows what they do. In this way it is a much more complex build, but most of the complex part of the build is the throat assembly.

Assembling the throat assembly (to many assemblies in that sentence)


Had almost the desired effect and straightened out the ply a bit but not entirely still it's a lot better than it was, and I think will be workable with the rest of the design now.



Two over sized spice racks


As far as the build goes I'm pretty much where I hoped to be. I'm really enjoying this build, I've been setting myself small targets each day and have planned it out (I'm a sad man) up until the point where I have to start soldering etc - in fact I haven't even looked at the crossovers etc, I'm hoping that the Crossover is optional.

Anyway my next step is by the end of Thursday I would like to have the throat assembly attached to the throat reflectors and phase baffle, sanded and painted black, then that's the back of the wood work broken. Then Friday I want to get the horn braces attached, then off to Newcastle for a gig.

Anyway next Update is likely to be on Thursday.

Rob

[discreet]

This is great. Can't wait for the next instalment. Getting stoked up to build a couple of BFM Jack 12s soon...
... you don't happen to have plans for Jack 12s, do you? No? Just a thought.

[lee4]

I work for a timber merchant,and our cut size ply/MDF supplier is in Reading.They are Arnold Laver,and thier ply is great quality.
Great work BTW!

[thinman]

I'll be very interested to hear what you think of these.

I've got a Deltalite-loaded wide-bodied Omni 10. I'm about to embark cutting it in half to make two 10.5s for easier transport although a few people on the BFM forum didn't recommend that I did! But then I'm a fool like that.

On the BFM site there were reports that the Omnis "chuff" on loud low signals but I've never noticed that with mine.

The plan is to then build a pair of Jack 110s for bas and convert the Omnis for PA use by fitting a crossfire piezo array. Much wood butchery to be done!

[thinman]

[quote name='lee4' post='888855' date='Jul 7 2010, 07:45 PM']I work for a timber merchant,and our cut size ply/MDF supplier is in Reading.They are Arnold Laver,and thier ply is great quality.
Great work BTW![/quote]

What's a reasonable price for an 8 x 4 sheet of 12mm birch ply these days? Everything at my local timber yard went up by 20% earlier this year.

[gilmour]

[quote name='thinman' post='888859' date='Jul 7 2010, 07:56 PM']I've got a Deltalite-loaded wide-bodied Omni 10. I'm about to embark cutting it in half to make two 10.5s for easier transport although a few people on the BFM forum didn't recommend that I did! But then I'm a fool like that.[/quote]

I think that an Omni10.5 is slightly larger than half an Omni10 so reducing the size may not work. TBH That sounds like quite a lot of work - I'd be tempted just to build new boxes and salvage the parts.

Only chuffing I've noticed is when I have a single Omni10.5 and have it cranked right up - but TBH I'd expect that from any single 10" driver tryign to gig on it's own. Never experienced it with two cabs.

[peted]

I love my Omni 10 to bits but would be intrigued to hear your thoughts on the completed Jack 10. Great build thread!

[lee4]

[quote name='thinman' post='888862' date='Jul 7 2010, 07:57 PM']What's a reasonable price for an 8 x 4 sheet of 12mm birch ply these days? Everything at my local timber yard went up by 20% earlier this year.[/quote]
Without checking at work,about £30-£40 + vat.Do you want Latvian or Finnish Birch ply?The Finnish is the best,but be prepared to pay top dollar for it.
All timber has risen in price recently.Factors such as a poor harvest,the Finnish stevedores strike(softwoods only) and good old greed are all to blame.

Edited July 8, 2010 by lee4

[gilmour]

Just spent a load of time searching for this, but has been moved to a differnt forum, my [url="http://basschat.co.uk/index.php?showtopic=11971"]last thread[/url] and it's 9,500 hits seemed ok there? It's not a problem but would've been good to get a PM to save me searching for this.

Anyway, a week of inclement weather, plus having to finish of a project in a primary school, and a weekend jaunt to Newcastle (f*** that's a long way) has left me behind on these. I'm thinking it's highly unlikely I'll have them finished for tomorrow! So no surprises there.

I only have a couple of hours of woodwork left, but after that there's a fair list still to be ticked off:
- Filling
- Sanding
- Finishing (carpet or paint?)
- Installing the drivers
- Make the piezo array, (just finding my piezos is a challenge)
- Make the crossover (still need t order the components)
- install crossover
- dampening
- Screw the back on
- Make noise

All in all I think 2 - 3 days more work to get it done properly.

So this is where we're at.

After finishing the throat assembly I went back and painted the phase baffle black. I decided to do at this point as it's going to be tricky to do this later on. I also wanted to install a wire mesh to protect the speakers, but something suitable from B&Q would have cost me over £30! So instead I opted to buy an 8'x4' sheet of expanded metal lathing from Selco (£12).

This stuff:


It's intended use is for plastering, it's the thing you plaster over. I thought I'd picked up a bargain, but truth be told I was being a skin flint. My arms are covered in cuts form cutting it, it's much wider than the normal wire mesh, so I have paranoia about air leaks, it's to bendy and it looks sh*t. I would not recommend this cost cutting exercise!

Anyway once that was done and attached I attached the baffle and throat together, cut my throat reflectors and cutting the venting duck holes.

The throat reflectors are quite small pieces that also require two tricky angles on them, these were a PITA - to small for the circular saw, so I had to use the jigsaw, leading to not perfectly flat cuts, so had to plane them flat.

Hey presto... finished throat assemblies....


Up close


It' not my neatest work, and the black paint and excess PU make it look really messy, but it is definitely the most complex build, and given my corner cutting on premium materials I'm pleased with it. Although it will need a little filling and good rub down.

Because of my cheap wire mesh I've been paranoid about air leaks and may have used a little too much PU adhesive (the stuff expands you know)


Much more and it'll start to compromise the interior volume of the cab.

I'm pleased with my vent ducts


But have ballsed up on one of them - I some how misplaced it by an inch...



Can you see the bit of ply through the top hole? That's the Throat Reflector, the vent should go underneath this, it's not a good thing that I can see it as like that it will bugger up the cabs porting. I now need to figure out a way to fill the hole and recut the duct - what a ballache. You may also notice the brown smear - that's 100% pure Gilmour blood, again curtesy of that bloody wire mesh.

That's the bulk of the wood work done, and certainly all of the small fiddly bits.

[gilmour]

Just as I was about to post this I decided to dry fit it all together to see how it looks. Were it not for the warpped ply it would look great.



It's a sizeable cab for a 2 x10 (about the same size as two O10.5's) but given the performance of Bill's oher cab's that I've built thus far that doesn't bother me as it generally means moving around half as many cabs.

For scale here it is next to my (mostly redundant) TRB:



And here it is with some spare bits of ply popped in where the Horn Mouth panels need to go (these are the last thing for me to cut out so what's in there is some scrap I had about that's roughly the right size).





I'm well pleased, I may try and do some more today, but yesterday I spent more time getting everything in and out of the shed than I did actually building, one minute hail, one minute sunshine. So instead I may brave my projects cupboard and search for my piezos and get cracking on the array.

They're in there somewhere:eek:


That is all.

R.

[discreet]

Nice one Rob, can't wait to see the finished article.

[gilmour]

When looking back at that last post I was embarrassed by the state of the Horn assembly and even though most of it won't be visible and the rest will be painted I decided to hit them up with the sand paper, scrpaers, elbow grease and a little filler to neaten it up. Looks much better...

[Phil Starr]

Enjoying this thread, keep up the good work!

[gilmour]

Braved the projects cupboard, took me bloody hours, they weren't all in one box instead spread throughout the cupboard...


That's 33 piezos there - I can't understand why I'd have an odd number, so Im sure there's another on in there but I really can't be bothered to look for it now. I'd need 48 (24 piezos per cab) to do crossfiring arrays, so I'll stick with the straight array - 12 per cab. And that will leave me some for a future project (or my third cab wood)

Pepper enjoyed the packaging.


Then he decided that the piezo field is the natural hunting ground of the domestic cat.


Might find some time Sunday, if not it will be midweek.

R.

[quote name='Phil Starr' post='896923' date='Jul 16 2010, 10:08 PM']Enjoying this thread, keep up the good work![/quote]

Thanks dude, it's good to know people are enjoying this. Keeping a diary keeps me going as I know people are watching.

[bumnote]

how many piezos?
how much are they

[gilmour]

From CPC £3.63 each (i think 20p off if you buy more than 10!)

I didn't pay that much for them, they used to be dirt cheap, like £1.50 each which is what I paid, and I also bought a job lot of some one on Finnbass who had a build he never managed to complete.

Bill uses a lot of Piezos in his designs as when you meld them into an array they give a very good flat response, as good as a much more expensive Compression driver. However they rocketed in price massively in over the last year, and I've noticed Bill increasingly incorporating compression drivers into his newer designs as it's now close to the point where the price difference is only slight.

[bumnote]

im toying with trying a couple of 1x10s or 1 x12s like the one shown in bills web site but done in the retro style

[RichardH]

[quote name='thinman' post='888859' date='Jul 7 2010, 07:56 PM']I'll be very interested to hear what you think of these.

I've got a Deltalite-loaded wide-bodied Omni 10. I'm about to embark cutting it in half to make two 10.5s for easier transport although a few people on the BFM forum didn't recommend that I did! But then I'm a fool like that.

On the BFM site there were reports that the Omnis "chuff" on loud low signals but I've never noticed that with mine.

The plan is to then build a pair of Jack 110s for bas and convert the Omnis for PA use by fitting a crossfire piezo array. Much wood butchery to be done![/quote]

I would suggest making another Omni 10 and the use the pair for PA, rather than hacking the one you have about. Bigger boxes, but I think they would be a more capable rig. Then make the 2 Jack 110s for your bass rig. Then when you only need a mini PA, use a single Omni 10 for bass and the Jack 110s for the PA.

[gilmour]

[quote name='RichardH' post='897819' date='Jul 18 2010, 09:48 AM']I would suggest making another Omni 10 and the use the pair for PA, rather than hacking the one you have about. Bigger boxes, but I think they would be a more capable rig. Then make the 2 Jack 110s for your bass rig. Then when you only need a mini PA, use a single Omni 10 for bass and the Jack 110s for the PA.[/quote]

That's a clever, thought through, and eminently sensible suggestion. I think a pair of Omni 10's would make a very capable PA - I used their smaller brother at a reasonable sized gig last night [url="http://finnbass.com/showthread.php?p=110439#post110439"]Review Here[/url]

Edited July 18, 2010 by gilmour

[RichardH]

[quote name='gilmour' post='898000' date='Jul 18 2010, 12:55 PM']That's a clever, thought through, and eminently sensible suggestion.[/quote]

I have my moments