Building the 4345/4344

[Ian Mackenzie]

Probably of more significance is just how to go about the job.

So here are some practical hints for the 4344/4345 builders.

Its not a weekend L100 project, more like 3-6 months..a labour of love. Take your time, plan out the steps for the job and how you are going to go about it. In my 4345 there were over 50 tasks to complete not counting the paint job.

This is a tricky project, the baffles are mirror image pairs and the enclosure must be assembled to a prescribed order.

In particular care must be taken with the baffle cut out. As they are mirror image pairs for left and right and you must be careful to draw up the layout of the baffle before cutting and check everthing at least twice.

I will redraw the overall baffle dimensions for the actual baffle size as per the 4344 construction approach.

You must have a Jasper circle Jig and a powerful Router with a new cutter, plenty of ventilation and a Jig to hold the baffle.

Ian

[Ian Mackenzie]

I would cut the baffle and then router the driver cut outs as the first steps, taking care to sketch up you plans life size on the baffles, check and re check before any cutting.

Then proceed for with the driver bolt holes and fit up the the horn, and slot. These fittings are precise so care must be taken as you only get one shot at it. Make a practise Jig for the horn and slot first to ensure a perfect fit up of the /horn drivers. This also applies to the 2122H, there is little tolerance for error here. A drill press/jig will help as the holes must be perfectly plumb.

If you are using a laminated baffle do the above step after the fabrication of the laminate as the holes will fill with glue!

When you are done there cut and trim the port holes for a snug fit. You can make the outer skin the front edge and insert the port into the rear layer, it looks great done that way. Alternatively if using 1 inch MDF, place the layer of 3/4 MDF behind the baffle and use as an insert.

If you plan to use laminated 3/4 MDF like I did, then laminating is the next step. So make a frame jig to hold the baffles when they are glued to stop them moving. Use plenty of PVA glue and pressure with Glad Wrap clear plastic film around the edges to stop the baffles adhering to the jig. You will also need to rebate out the rear layer for the flang of the 2307 and 2405. I did this pre the laminating but suit yourself.

When the baffle is complete the Dog Box panels can be cut. Assemble with glue/screw and then carefully postion on the rear of the baffle allowing clearance of the Pads (and ports in the case of the 4345). The Dog Box should then be glued and screwed into place.

A support brace for the compression driver like this one will need to be arranged. I used hard rubber as a support to avoid vibrations. You can also ues a strap around the driver if you like but the weight should be sufficient to stop it going and where. (unless you plan to ship the boxes).

You will also need to consider how to go about assembling the plate for the Foil Cal. I used 3mm aluminium plate and cut it to size, the carefully drilled the holes for the pad knobs and fitted it into a rebated area within the front baffle as seen in the picture below.

That about does the baffles, but its about a weeks work in that.

Ian

[Ian Mackenzie]

Here the baffle being fabricated/assembled.


Ian

[Ian Mackenzie]

Here the Dog Box being assmbled and mounted on the rear of the baffle. As you can see there is zero tolerance for errors, so take care.

Ian

[Ian Mackenzie]

I will post the other drawings later in the week.

Ian

[Ian Mackenzie]

With any luck your baffles wiill turn out like this example.

The details and exacting features are all visible.

Ian

[Ian Mackenzie]

Before I do any more posting here I would like to ask Don how these types of threads or edited aspects there of can be stored and indexed or catalogued on the forums or in the JBL/Lansing Library so that a member can see that its available.

(There seems little point to it if this can't be arranged.)

I would add a lot of very useful technical information and images are posted of equal or greater value than in this thread and then lost as all the new threads roll forward and i don't see the search function as a solution.

We seem to be treading over old ground a lot and as a Heritage Forum I think we could be doing this better.

Don, can you assist?

Ian

[Hofmannhp]

Originally posted by Ian Mackenzie
Before I do any more posting here I would like to ask Don how these types of threads or edited aspects there of can be stored and indexed or catalogued on the forums or in the JBL/Lansing Library so that a member can see that its available.
......Don, can you assist?

Ian

Ian....I agree completely ......

I think that we can add some more heritage systems in the future to this kind of data base.

Don, what do you think...?

HP

[Ian Mackenzie]

Apparently there is reference area, so at some stage when these drawings can be put into Autocad they could be saved there perhaps.

Go here for more practical information about building the 4345.

http://audioheritage.csdco.com/vbull...=&threadid=952

I will be opening my own home page as a reference of these designs shortly, in the interim if you need assistance send me a Pm.

Here are the remaining drawings, adapted from the 4344 drawings posted earlier.

Ian

[Ian Mackenzie]

More dawings.

[Ian Mackenzie]

This is the front elevation.

[Ian Mackenzie]

Here is the top elevation.

[Ian Mackenzie]

This drawing details the enclosure joints.

[Ian Mackenzie]

Here is detailed side elevation of the bracing.

[Ian Mackenzie]

Here the rear elevation with details of the bracing and boot opening.

Ian