Jack 210

[thinman]

[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]

Thanks for the suggestions.

My Omni 10 only has 4 piezos - I doubt that would be enough for PA? I would have thought I'd at least have to add another 4 in a flat array or even go crossfire melded?

I'm not certain I'd want to lug a pair of Omni 10s about for PA use - I already have a pair of T39 subs so I think Omni10s as tops may be a bit overkill (and I'd need a bloomin' trailer!)

Maybe I'll just make a pair of Jack 110s and use the Deltalites from the Omni 10.

[thinman]

Actually, speaking of piezos and how pricey they are now, Leland Crooks who posts on Bill's site runs [url="http://www.speakerhardware.com"]Speaker Hardware[/url].

He's not allowed to ship Eminence to the UK as Adam Hall has the distribution rights but he tells me he can do anything else.

His 1016 piezos are only $2 (about £1.30!). Obviously there's shipping and VAT but when buying a good quantity I think it might pay in. Leland suggested UPS's flat-rate boxes that go from $10 to $50.

[gilmour]

[quote name='thinman' post='898296' date='Jul 18 2010, 07:14 PM']Thanks for the suggestions.

My Omni 10 only has 4 piezos - I doubt that would be enough for PA? I would have thought I'd at least have to add another 4 in a flat array or even go crossfire melded?

I'm not certain I'd want to lug a pair of Omni 10s about for PA use - I already have a pair of T39 subs so I think Omni10s as tops may be a bit overkill (and I'd need a bloomin' trailer!)

Maybe I'll just make a pair of Jack 110s and use the Deltalites from the Omni 10.[/quote]

My O10.5s have a 4 piezo flat array and they're great for PA. When you consider most commercially available cabs only have 1 !

As far as I'm aware most people have suggested that it's not worth changing an Omni for a Jack as the performance diff is very subtle. Size wise They're pretty much the same.

Also how do the T39s go with the Omnis?

[quote name='thinman' post='898332' date='Jul 18 2010, 07:50 PM']Actually, speaking of piezos and how pricey they are now, Leland Crooks who posts on Bill's site runs [url="http://www.speakerhardware.com"]Speaker Hardware[/url].

He's not allowed to ship Eminence to the UK as Adam Hall has the distribution rights but he tells me he can do anything else.

His 1016 piezos are only $2 (about £1.30!). Obviously there's shipping and VAT but when buying a good quantity I think it might pay in. Leland suggested UPS's flat-rate boxes that go from $10 to $50.[/quote]

That's really good to know, thanks.

[gilmour]

[quote name='thinman' post='898296' date='Jul 18 2010, 07:14 PM']Thanks for the suggestions.

My Omni 10 only has 4 piezos - I doubt that would be enough for PA? I would have thought I'd at least have to add another 4 in a flat array or even go crossfire melded?

I'm not certain I'd want to lug a pair of Omni 10s about for PA use - I already have a pair of T39 subs so I think Omni10s as tops may be a bit overkill (and I'd need a bloomin' trailer!)

Maybe I'll just make a pair of Jack 110s and use the Deltalites from the Omni 10.[/quote]

My O10.5s have a 4 piezo flat array and they're great for PA. When you consider most commercially available cabs only have 1 !

As far as I'm aware most people have suggested that it's not worth changing an Omni for a Jack as the performance diff is very subtle. Size wise They're pretty much the same.

Also how do the T39s go with the Omnis?

[quote name='thinman' post='898332' date='Jul 18 2010, 07:50 PM']Actually, speaking of piezos and how pricey they are now, Leland Crooks who posts on Bill's site runs [url="http://www.speakerhardware.com"]Speaker Hardware[/url].

He's not allowed to ship Eminence to the UK as Adam Hall has the distribution rights but he tells me he can do anything else.

His 1016 piezos are only $2 (about £1.30!). Obviously there's shipping and VAT but when buying a good quantity I think it might pay in. Leland suggested UPS's flat-rate boxes that go from $10 to $50.[/quote]

That's really good to know, thanks.

[SteveO]

[quote name='thinman' post='898332' date='Jul 18 2010, 08:50 PM']He's not allowed to ship Eminence to the UK as Adam Hall has the distribution rights but he tells me he can do anything else.[/quote]

Hows that work then? I'm in the process of ordering 6 Eminence drivers from Thomann to a UK address (which i'm flying over to collect as its about 80 quid cheaper than mailing to Norway what with the taxes and stuff ) they've accepted the order and there doesn't seem to be a problem, although they haven't been paid for, or arrived yet. Maybe its a Europe thing?

[thinman]

[quote name='gilmour' post='898431' date='Jul 18 2010, 10:23 PM']My O10.5s have a 4 piezo flat array and they're great for PA. When you consider most commercially available cabs only have 1 !

As far as I'm aware most people have suggested that it's not worth changing an Omni for a Jack as the performance diff is very subtle. Size wise They're pretty much the same.

Also how do the T39s go with the Omnis?



That's really good to know, thanks.[/quote]

I use the Omni10 for my bass and the T39s for the PA.

I've got a bit of a strange PA but it works quite well - I've a pair of db Technologies Opera 405s which are bi-amped 250w+50w active and they do fairly well full range for smaller places for vocals and little bit of kick drum. For the larger places I have a crossover and send everything 120Hz upwards to the Operas and everything below via a StudioMaster 700D into the pair of T39s. Seems to work very well - sounded great in a marquee last week. Just looking for a big scrap of ply to make a "V" plate for them now. And last week a lady also found the mouth of a T39 a very handy place to keep her handbag whist dancing.

[stevie]

[quote name='SteveO' post='898468' date='Jul 18 2010, 10:57 PM']Maybe its a Europe thing?[/quote]

In theory, the EU is a free market and companies cannot restrict trade in their products within the EU. What companies do outside the EU is their business.

[gilmour]

As a reward too myslef for finishing a project yesterday I thought I'd have the afternoon off today and work on my cabs. As I was a little bored of woodwork by this point I thought I'd have a go at the Piezo Arrays.

So 12 Piezos per cab - straight array.

I didn't want to make a song and dance about this, just a dance, so I built a jig! Badoom tish. This will ensure all the cuts are the same - a few off cuts of wood, some screws, 20 mins later .... hey presto ....



In action



Getting there



At this point I realised I should be a little more systematic, so I removed all the piezo elements



Just as I was about to start work on the second array I thought it might be good to see a size comparison before and after...



The piece of wood they are on is actually the side of the cab, so 12 uncut would be too big, but cut they'll fit with ease - I could even squeeze in an unlucky 13th

I assume the reason for making them as an array is to fit more piezos in the same space, you'd have to check with Bill, but I imagine it will also help flatten response, or improve dispersion or something technical like that.

Both arrays cut:

[peted]

Holy Cow that's a lot of piezos!

[gilmour]

[quote name='peted' post='901063' date='Jul 21 2010, 04:47 PM']Holy Cow that's a lot of piezos![/quote]

hehe yes you should see some of the builds on Bills forum, where they're using 24 per cab! I'm going to be using them for PA duty, so the extra top will be appreciated, although I did a gig last Sat with 4 a side and that was plenty!

I'm sure this would be overkill for bass, so if anyone is thinking about a Jack for bass then I'd just go for 4 or maybe 8 straight piezos, and that will still give you a pretty hifi sound.

Obviously I will try it with bass (who could resist) but as I have 2 O10.5s and an O15 I think it unlikely I'll find a use for the Jack for Bass backline, as the O15 will produce more bottom end, and the O10.5's are more portable. However If I do I'll likely install a switch to turn off some of the piezos, but I'll cross that bridge if and when I come to it.

[gilmour]

Found time to glue the arrays today.

FIrst quick trip to hobbycraft for some 'airfix' glue.

I want to make sure the arrays are flat and straight so this calls for another Jig. my first attempt was not successful because the ply I've got is so warped. I was searching for a flat surface - and then I spied the living room coffee table Role of tin foil, some old shelves, clamps and my spirit level later ....



When dried I picked up the arrays and they felt very weak and liable to snap in the middle. I'd kept aside all my off cuts thinkg they'd be seful for model making, but decided to put them to another use:



Essentially I used the off cuts to strengthen the array form the rear. I was sure to stagger each side to try and reduce weak points.

Finished for the day (had a gig at 6pm)



I'm pleased they look pretty smart. They still feel a little brittle but hopefully once the glues had a coupe of days to go off this will change, otherwise I'm not sure what to do. Anyone got any suggestions?

Before these are finished they need a light sanding and spray painting, possibly I'll do something funky with the colour - I have some chrome paint burning a hole in my projects cupboard. I'd also like to find time to fill the holes - but that's non essential.

I'm playing at Womad this weekend, so am off there first thing in the morning, so it's likely to be a while before the next update.

Peace'n'hair grease

R

[Phil Starr]

[quote name='gilmour' post='902509' date='Jul 22 2010, 11:08 PM']Found time to glue the arrays today.




I'm pleased they look pretty smart. They still feel a little brittle but hopefully once the glues had a coupe of days to go off this will change, otherwise I'm not sure what to do. Anyone got any suggestions?



Peace'n'hair grease

R[/quote]
You've left the flanges on the sides so run a batten along the back and fix the horns to the battens which will stiffen them up

[gilmour]

[quote name='Phil Starr' post='903377' date='Jul 23 2010, 04:51 PM']You've left the flanges on the sides so run a batten along the back and fix the horns to the battens which will stiffen them up[/quote]

Yeah there will be a batten along there when I attach them to the cab, was jsut wondering if there was a way to stiffen them before adding them to the batten. I've been toying with using some epoxy or similar. It'll probably be fine They're pretty sturdy - jst beeing over paranoid as last time I made some I dropped them and cracked them

[Alien]

[quote name='gilmour' post='902509' date='Jul 22 2010, 11:08 PM']When dried I picked up the arrays and they felt very weak and liable to snap in the middle. I'd kept aside all my off cuts thinkg they'd be seful for model making, but decided to put them to another use:



Essentially I used the off cuts to strengthen the array form the rear. I was sure to stagger each side to try and reduce weak points.[/quote]

Now that's a bloody good idea. I reckon you should post this pic on Bills forum - I've never seen that done before over there.

A

[Finbar]

Probably would have used the offcuts the other way up, so they have more area in contact with the assembly? I'm watching this with interest though Might need to build myself some BFM stuff soon D:

[gilmour]

[quote name='Finbar' post='904341' date='Jul 24 2010, 09:41 PM']Probably would have used the offcuts the other way up, so they have more area in contact with the assembly? I'm watching this with interest though Might need to build myself some BFM stuff soon D:[/quote]

I had initially done that, but then changed my mind. I felt that that flat part of the bracing will add more strength that way around (effectively creating box tube) as opposed to the other way around. The 'airfix' glue melts the plastic a little and then when is sets forms a pretty tough bond so that should be ok. But time will tell, part of me still feels they should have been the other way.

[Finbar]

If it was the flat side down, it would still create a box tube effect, just a smaller one. As a general rule, the better a mechanical joint you can make the better, so I'd definitely try it the other way round if you do another, just to see which is best! Sounds like you're using polystyrene cement. It's as good a glue as any for that job I should think. Didn't know they were plastic though - assumed they were metal! But it makes sense, given the cost of them

[gilmour]

After a week stressing about work, and chasing around bits of paper I decided to give myself the weekend off and do something I enjoy - get pissed off with bent ply and glue crap to my hands

First of all, remember this....



My misaligned vent duct hole. I needed to fix this, first thing I tried was a circular hole cutter, do popped one out of ply



It was a little large, but I thought I could sand it down - but it was too big and that pissed me off too much, so I sought out another solution.

Whilst looking for inspiration in the shed I found an old curtain pole, it was a perfect fit I cut 12mm off of the end, and popped a screw in the middle to hold it by.



Then PU'd it in place, and redrilled the hole in the correct place.



Not perfect but at least it will work.

then on to the real work. First job was all the baffle braces, 12 of the bloody things, they were quite fiddly. I was quite engrossed in the work and forgot to take pics. Then I aligned everything and glued the bottom on.



Then I popped them on top of each other:


Felt quite proud until I noticed I'd somehow used only 2 braces on one side of one of the cabs! Aaarrggghh. I've decided to leave it in the hope that it will be solid enough, If not I guess I'll go back and add two additional braces *sigh*

One of the best things about the baffle braces is that they make a very hand work station


Note that the cuppa takes first place.

Glues up the horn sides next. These had been pre cut.



These were a right PITA, largely because of that sh*tty ply I've been using so nothing quite lines up. Note the spirt level/straight edge in the pic - In an effort to make the ply straighter a method I've adopted is to Clamp my straight edge to it whilst gluing In the hope that when the glue goes off it will hold the pieces straight - It's worked to a point, but not perfectly. I doubt very much these cabs will be 'as advertised' given the warped ply and my cock fingered attempts at cutting and gluing, in fact it'll be a miracle if they don't wobble all over the place! Oddly though (given the performance of my O10.5s at the last gig) I'm still confident that they'll be better than anything else I could have afforded.

Then the driver spacer went on, and the phase plug extension, I imagine it works in much the same way as throat filler in the O12s (and DRs ?). FWIW it would have been easier to do this much earlier in the build when I was making the phase baffle.



Then stripped excess pu, filled any holes where screws had come out and a light sand (full sand at the end of the build) and I have something that's closely resembling a pair of Jack 210s



Tops to go on next, then the sides and it's onto installing the electrics. I also will probably get a top hat to install before doing this.

Putting the top on will be interesting as it will reveal how out of line eveything is curtesy of my ply, bad technique, impatience, general woodworking ignorance... I can't wait

I have a deadline to have these finished by Monday 9 August, as we have a gig on 13 August with no budget for PA, and I'd like to give them a run at practice first.

That is all.

Edited August 1, 2010 by gilmour

[discreet]

Great work Rob, nice one. Looking forward to the next instalment.

[Mr. Foxen]

[quote name='gilmour' post='912228' date='Aug 1 2010, 08:31 PM']In an effort to make the ply straighter a method I've adopted is to Clamp my straight edge to it whilst gluing In the hope that when the glue goes off it will hold the pieces straight - It's worked to a point, but not perfectly.[/quote]

I think if you call this 'pre-tensioning' it is cunning engineering, makes the panels less likely to resonate.

[Scot Bass]

Hi Gilmour,

Looking good. I had the same problem with sh*"e plywood but my 2 J110s sound really good.
The one thing that I forgot to do was breaking in the drivers.
They loosened up with use and you might want to break them in so you can run the cabs at full pelt from the word go.

Cheers,
SB

[gilmour]

[quote name='Scot Bass' post='912524' date='Aug 2 2010, 09:38 AM']Hi Gilmour,

Looking good. I had the same problem with sh*"e plywood but my 2 J110s sound really good.
The one thing that I forgot to do was breaking in the drivers.
They loosened up with use and you might want to break them in so you can run the cabs at full pelt from the word go.

Cheers,
SB[/quote]

Cheers dude - glad to know I'm not the only one who's ply provides a problem.

This is my 3rd BFM build so I know about breaking in drivers, two of the four I've got are second hand so should be broken in already. Just need to get around to doing the others - I've only had them in the cupboard for 18 months!

[bumnote]

great thread

i just bought the plans for the jack 10 and 12.

Im going to build a 12 although im not sure if its going to be 2 single 12s or a 2x12.

thats a great build thread and seing your project has persuaded me to have a go so thanks.

[discreet]

[quote name='bumnote' post='912561' date='Aug 2 2010, 10:16 AM']thats a great build thread and seeing your project has persuaded me to have a go so thanks.[/quote]

Plus the one! As bedtime reading I've been scrutinising the Jack 12 plans for several weeks and am about to 'make with the sawdust'.
I've also been in communication with an authorised BFM builder, who had this to say, FWIW:

'What I'd also suggest is building a pair of Jack12's rather than a single 212 - it'll make them stupidly easier to manage in terms of lifting, and you'll also get fractionally more bass as well.'

Though my research leads me to believe I'll only ever need one Jack 12, I'm going to build two eventually - just in case.

Whatever you decide to build, good luck with it - don't forget to post your build diary...

Er... sorry Rob, I've gone OT a little... :blush:

[bumnote]

[quote name='discreet' post='912588' date='Aug 2 2010, 10:38 AM']'What I'd also suggest is building a pair of Jack12's rather than a single 212 - it'll make them stupidly easier to manage in terms of lifting, and you'll also get fractionally more bass as well.'[/quote]

I have read the same comment and I am in two minds. The advantage of a 2 x12 which I would use with tilt back wheels is you can drag like a trolley, which is how I move my 2x15 and find it pretty easy. The two 1x12 you would have to make two carry trips, or possibly join them together as there are pictures on Bills site.

Gilmour are you going to paint them or cover them?