BillFitzmaurice.info

hahaha, I'm sure we've all had a scare from a louder than expected blast of noise...
Mine was with headphones, late at night, around 3am, trying to finish some work... had been listening to some music, forget the track/artist but there sneaky mixing artist had made the last few min of one track very quiet, forcing me to turn up the volume to full... then when the next song came in it was a vocal sample of a guy saying "y'all ready!" (only found this out after re-listening the next day... at the time it was just a blood curdling scream), only on the right speaker, and full blast with a bit of reverb to make it sound like it was behind you.... needless to say the kitchen was to the right of me and I was 100% sure there was a 7 foot tall 300lbs bandit ready to bash my head in with a baseball bat. I physically jumped out of my chair and clothes-lined myself on my headphones... and as Michael said, the adrenaline was instant and copious, my heart still hasn't recovered...

The really stupid thing is though... that it happened again! haha, I had the stupid album on loop! you would think I would have learned my lesson, but it was so realistically placed and REALLY sounded like it was in the room with me!

sorry for going off topic, just wanted to thank Michael for reminding me of that crazy night.

Thanks for sharing fellas.

Made the first set of crossovers tonight. I've used speaker wire as a kind of bus system and soldered to it where required. I've stuck stuff down with hot glue. The idea is that the IN from the jacks on the back panel will go to the LP board on the right side, and link out to the HP board on the left, with the link wire hot glued along the baffle under the speaker

After filling, sanding and vacuum cleaning the cab off I'm finally at the first coat of tuff cab. I wrote an exhaustive to do list about 2 or 3 weeks ago, I cannot remember and the progress has been really good since then. I know i said i would post the list if anyone was interested. No one was, but I will post it anyway tomorrow - it may speed someone elses build up like it has mine, near the end.

Charles Jenkinson wrote:After filling, sanding and vacuum cleaning the cab off I'm finally at the first coat of tuff cab. I wrote an exhaustive to do list about 2 or 3 weeks ago, I cannot remember and the progress has been really good since then. I know i said i would post the list if anyone was interested. No one was, but I will post it anyway tomorrow - it may speed someone elses build up like it has mine, near the end.

I'm interested In knowing although it will be a long time til I get to build tops.

OK. Here's the To Do list I made during some planning time to help me tick the jobs off.

To do list: (HSN = Hind Sight Note)
Mark off 'install position' of piezo array mounting rails (don't fix yet)
Mount backing blocks inside for rubber feet screws
Cut out back panel for jack plate (& drill jack plate for array switch) - cut hole and recess for flange
(jack plate to not be too low as to interfere with back panel fixing rail)
HSN: When drilling jack plate rest it on something soft and clean, so it doesn't mark the paint!
HSN: Use a follower plate fixed into bottom of router and make a slightly bigger jig plate for cutting flange recess

To buy:
Painting: Is a half-roller required to get behind pizzer rails? Not necessary!
Get small tie wraps, for fixing coils/cables (and to catch a service loop on back of array)
Get handle fasteners M5x30 csk + nylocs or, 10-24 UNC csk skt hd 12.9 + nylocs
- Use M4x25 for lites, (M4 fits strap handle end piece csk better)
wiring block connectors for HP-filter outs
buy more array wire for wiring internals from jacks to boards etc. (speaker wire 1.5mm^2) HSN: 1.5mmsq too heavy, use 18ga

DO x-over layout: Decide how big a board/s required & where x-over boards to fix & wires to run in cab (glue in).
- mount on vertical boards between the side braces. LP on RHS and HP on LHS (viewing on back).
Make x-overs, to point where they can be fixed and wired in.

Figure out internal wire runs
How many wires need running for array? (2 pairs)
Buy a molded capping suitable for array wire/s duct - B&Q
Drill through sheath (didn't do this) and install duct for array wires, on topside (install and seal wire pairs! Mark UPP & LOW (*))
- NB: both sets of array wires must initially be long enough to run to array switch! (for phase setting)
HSN: Ran wires down centre port duct and glued into a duct made out of 3mm thick strips and fixed with hot glue.

Phase check drivers with 9v battery
Trial Fit drivers – leak test on horn areas (incl. array wire duct with wire/s fitted - seal at horn end)
Listen for clattering internal phase plug - reshape if necessary (but 1/2" clear - shouldn't touch!)
Bed drivers in, in situ
Fix leaks

Do some painting: (in ducts &) behind where piezo mount rails will fit
paint & fix diffusers onto array
Wire up piezo's on their own
Cut & fix piezo mount rails

Drill strap handle fixing holes (3.5mm)
Drill feet fix pilot holes
Drill thru, open out and countersink cab back
Check all staple heads are recessed & fill and fine sand cab
Mask foam seal strip area & round top hat flanges.
Finish paint cab
Install feet
Glue front phase plug/dome in
Install window seal foam strip

Make up some speakon leads

Fit driver and array (solder UPP and LOW wires to UPP and LOW array parts)
Install x-overs boards
Preliminary wire both UPP & LOW array into block connectors on HP filter out
- don't wire thru array switch yet, till phase is determined.
Install jack plates, speakons and array switches to back panel, and wire thru to x-over boards
- don't wire thru array switch yet, till phase is determined.
- tie wrap wires to bottom braces and back panel braces for strain relief
Set the phase of array to driver at x-over freq, and wire appropriately to switch / HP board.
Install pillow fibre and acoustic foam
Fit back & leak check
Tidy service loop on array
Install handles & plastic corners

Oh man that list has made me realise just how much work I've got to do on my OT12s.

You mean you actually read it? God bless you!

It has really helped me.

That took me a full work day (including doing a cross over layout sketch & piezo physical wiring layout for my soldering tabs orientation). I have a job where the guy I'm working for is a perfectionist and has to do it all himself, because 'no one else can do it as good as him'. ...He cannot delegate. Hence my abundance of planning time.

I read most threads on here! I should probably use that time to get my own list done though really, I just don't think I want to realise how far away things are from being done.

Well, I'm more a can do master of the understatement, than a straight out encourager. But, hell, it's the other side of the same coin.

You know what you need to do.

Your list brought back "bad memories" of my 4 OTop build. It is absolutely astounding how much work goes into tops. The crossovers and piezo arrays alone were a solid 2 weeks of work (few hours a day) for me. Figuring out the crossover layout, drilling holes, wiring, soldering, heat shrinking, etc. So time consuming! But, build it once, build it correctly and it'll last a long time. Great job, Sir!

miked wrote:Your list brought back "bad memories" of my 4 OTop build. It is absolutely astounding how much work goes into tops. The crossovers and piezo arrays alone were a solid 2 weeks of work (few hours a day) for me. Figuring out the crossover layout, drilling holes, wiring, soldering, heat shrinking, etc. So time consuming! But, build it once, build it correctly and it'll last a long time. Great job, Sir!

Oh man you're harshing my mellow over here.

Sorry; didn't mean to pee in your Corn Flakes. I had four crossovers to build, four arrays and cabs to wire, etc. It just took me a long time. Of course, "time" is subjective. I work long days (job+commute) and have a family at home. What took me two weeks, might take someone else just a few days. Maybe you're "someone else?"! I'm trying, here.

Charles,
Great progress mate.
Yes I read it too (I also read everything), and the list seems to be getting you closer to the line.
Whatever works aas far as I'm concerned.

Keep at it...

This is the duratexing over with. 2 foam rolled layers and 1 textured roller. You can still see a bit of wood grain through the texture in places, though i did sand the cab first. I don't know what most people feel about duratex application but i was going over my marriage vows, particularly the 'for better or for worse' one. I don't have the patience for perfectionism, and that includes taking effective pictures of duratexing.

I hit my cabs with 2 layers with the textured roller (for the outside surfaces anyway), and left it at that...