Jump to content
Why become a member? ×
  • advertisement_alt
  • advertisement_alt
  • advertisement_alt

1x12" Cab Design Diary


Phil Starr

Recommended Posts

[quote name='Phil Starr' timestamp='1448926234' post='2919360']
You aren't going mad, first of all the pipes internal diameter is 64mm the outside is 68mm. secondly it depends how you enter the parameters into winISD as sometimes the manufacturers don't always use the same techniques for measuring as are assumed by win ISD. Then the box isn't exactly 50l as I built it oversized to allow for the volume of bracing the ports and speaker and any modifications I would make as the design developed, I didn't use all the extra volume I allowed. We also found two sets of data for the SM212 out there and then took our own measurements of the basic parameters which differed slightly from those published. If you go back to post #291 you'll see we actually measured the tuning of the cabs and the port dimensions are measured from the cabs we tested.

Well spotted though, and I had to double check all this so you are keeping me on my toes :)

Ultimately that's why you try and build prototypes and test them.
[/quote]

Ah, that makes sense. If I change the diameter to 64mm and add a few extra litres to the cabinet volume in winISD the predicted lengths are within a reasonable margin of error of the final measurement, and I've heard elsewhere that winISD estimates somewhat on the long side.

Link to comment
Share on other sites

[quote name='Phil Starr' timestamp='1448927705' post='2919383']
However I'm now pretty happy with the basic design of a 18mm cab with four pipe ports tuned to 50Hz so the slot port won't be a problem as we won't be recommending it. The availability of cheap hole saws means cutting the holes for the ports will be easier than forming the slot which was the only reason I went that direction. I found the wooden slot was tricky to form if you don't have plenty of clamps to hand.
[/quote]

I know proper woodworkers would flame me for saying this, but FWIW when I built my slot port cab I used screws as well as glue as I didn't have many clamps - I simply drilled a pilot hole then a clearance hole+countersink in the outer panel, then ran a screw right though nipped up tight - few of those per joint and it ended up clamped tight, no gaps anywhere and good strong joints.

Admittedly I did also use some biscuits which helped alignment, but even without the glue/screw method works fine provided you take your time and potentially dry-fit it all before glue.

Also re the hole cutting - I bodged a hole cutting jig on my router with a bit of old hardboard - 3mm straight bit, couple of holes in the hardboard, then screw the board on the router, another screw into the baffle, and I cut the speaker aperture perfectly round without any wobbly jigsaw action. I guess the same technique might work for port holes if you could get the pivot screw close enough to the bit.

I know Phil and the other experts will know all this already, but thought it worth sharing for the other first-time builders like myself.

Link to comment
Share on other sites

Nothing wrong with screws and glue, whatever your standard of workmanship. If you go to 6V6's build you'll see he was a very organised and careful builder. My cabs are all screwed and glued but screwed from the inside which makes finishing easier, especially if you are using Toughcab paint which doesn't stick to some fillers very well. I did consider making a modification to the slot port which would have made the build simpler but if you can cut the holes for the pipes then the whole build is so easy it became a no brainer.

Link to comment
Share on other sites

Tuff Cab goes a long way, I've used just under a litre to cover two cabs with two coats each. You need most for the first coat, as with most paints on an absorbent surface. I reckon you should just about be able to get three coats out of a litre but there won't be a great deal left for touching up scratches. I'm impressed really, I've always used vinyl up to now. Tuff cab is a whole lot easier, seems to last pretty well and looks a whole lot better than the matt black I used to use for big PA cabs.

Edited by Phil Starr
Link to comment
Share on other sites

[quote name='Phil Starr' timestamp='1449158480' post='2921189']
As soon as I can I'm getting someone to do some CAD drawings. I'll then re-post with some instructions and a series of photo's of the build. I'll do this as a new thread and let everyone know on here when it is done.
[/quote]

I'm an engineer and i make projects for a living, if you need any help with the drawings let me know, i work with AutoCAD every day. ;)

Link to comment
Share on other sites

Thanks guys, I think to be fair I'm going to go back and see who offered to do what and then pm everyone. I don't remember who offered first and I don't want to upset anyone who has volunteered. I just have to do the sketches and put the dimensions on them. No gigs this weekend and only one Christmas song to run through so shouldn't be too busy. Jim Lea anyone https://www.youtube.com/watch?v=0A8KT365wlA

Edited by Phil Starr
Link to comment
Share on other sites

[quote name='Chienmortbb' timestamp='1449826237' post='2927141']
Phil, are you still using the cab/cabs for gigging and what cabinet or cabinets have they replaced?
[/quote]

I rarely use both, too much for most venues, I often use one when we are in smaller venues just because they are physically small and light but I am currently working on a 15" Deltalite cab so that gets a bit of use at the moment. Two weeks ago I played at Exeter Chiefs after the Harlequins match and took the 15 with one of the 12's which sounded nice in a big venue.

Before that I used a 2x10 mainly with two PA cabs used as bass cabs for big or outdoor venues. These are the cabs I cannibalized for the Beymas so they were basically the 1x12's with a large horn doing the honours above 1600Hz..

The 2x10 is my go to cab but I'm usually experimenting with new designs so it's a bit random.

Link to comment
Share on other sites

Thanks for that Phil. It looks like you just love experimenting and so the 1x12 is really a labour of love and a gift to the BC community. You said a while back that you were working on a 2x10 design for after the 1x12. Has the 1x15 Delatite superseded that? Also sent a PM.

Link to comment
Share on other sites

[quote name='Chienmortbb' timestamp='1449831565' post='2927247']
Thanks for that Phil. It looks like you just love experimenting and so the 1x12 is really a labour of love and a gift to the BC community. You said a while back that you were working on a 2x10 design for after the 1x12. Has the 1x15 Delatite superseded that? Also sent a PM.
[/quote]

Well if you go right back the spec for the 1x12 was created on another thread here. As I said the 2x10 is my 'go to' cab so I wanted to make that available for everyone else. It's got an 'old school' voicing is a one handed carry and because it has some high excursion drivers can pretty much cover any gig without the bottom end farting out. Unfortunately Fane changed the drivers so I need to look into finding replacements. Developing a 2x10 is just about looking for some replacement drivers. I picked up the Deltalites from Blue Aran in a sale just before the Chinese pushed up the price of neodymium £66 ea so I couldn't resist. I decide they were too good to sit around doing nothing so I built a cab alongside the 1x12 with the other half of the ply sheet and used it for gigs whilst Stevie ran tests on the 12.

The original plan was to build a cab for the Kappalite 3015HO and publish that but GrahamT brought down his Kappalite (and went off with the cab :) ) The Deltalite compared reasonably well so that could become another published design. The current cab would take either driver with a flat response from the Kappa and a small mid-bass hump from the Delta.

My thoughts are to get the 2x10 and 15 out fairly quickly after the 1x12, which covers the basic cabs most people use. Stevie is working on some designs with tweeters and midrange drivers which might add to the stable of designs. So hopefully we can cover most basic options fairly quickly. It's all made the 12 a bit slow in gestation but should speed up the next designs.

Link to comment
Share on other sites

[quote name='Chienmortbb' timestamp='1449939824' post='2928228']
You mention that Fane changed (presumably discontinued) the drivers that are in your 2x10, What were those?
[/quote]They were sovereign 10-125's they still make something with the same name but with entirely different T/S parameters.

Link to comment
Share on other sites

  • 1 month later...

Hi John, and everyone else who hasn't lost patience.

I didn't want to answer this until I'd actually done something. Thanks to being stuck at home with a cold I have actually done some drawings and am going to get one of the people who have kindly volunteered to draw them up on their CAD stuff to do so. PM's coming tonight guys.

I've also got some pics I took of the various builds and some notes roughed out which I'll pull together and get put up.

I'll update as soon as I have something. The trick apparently is to keep off BassChat and actually do something in the real world :)

Link to comment
Share on other sites

[quote name='Phil Starr' timestamp='1455006028' post='2974851']
I love Basschat. There are four people freely giving up their time to produce plans and instructions for the build and just making it happen. Is it bass players?[/quote]

I've often looked into forums for guitarists and drummers but they never seem to work as well - I do think it is a bass player thing! We're used to playing a supporting role, often not getting much credit and being the keystone of a team. Go bassists! :)

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...