Medallion III+ Building Advice - Suggestions Welcomed

[ranger3]

I decided that my Lowther DX3s need a good home. They are currently collecting dust and I can't stand it.

I have asked my brother-in-law to build the Medallion III+ cabinets.

Having never built anything like this before, I'm asking for suggestions.

Pictures are welcome too.

When finished, I post the end product as well as listening impressions.

Thanks in advance.

[talaerts]

Not a real answer, but also check the "Big Fun" horn design if you have the space for it. It gets real bass out of your speakers.

[ranger3]

Originally Posted by talaerts

Not a real answer, but also check the "Big Fun" horn design if you have the space for it. It gets real bass out of your speakers.

I thought about it, but for now I don't have the room for such a beast.

I was hoping to get some bass out of the Medallion III+ cabinets, though.

[chrisb]

Not the simplest of builds even for a "seasoned veteran", but the plans are well detailed and fairly straightforward.

My only comments would be:

- take your time
- use the best quality high density plywood you can afford. (i.e. Apple-ply, Russian Birch, etc) - use MDF for test cuts / jigs but the Lowthers deserve far better for prime time
- if dadoing any of the internal panels via CNC or by hand made jigs, confirm thickness of materials from nominal values, and allow for variations of up to .5mm
- pre-veneer/finish as many of the visible internal panels as possible before or during assembly

The closest I've built to such a design were a couple of pairs of BLH for Coral Beta 8s and 10s. A little bit of a concern not having the rare drivers on hand to confirm tight fit in the loading chamber, but otherwise not particularly nerve-wracking, but certainly time consuming build - at least 100hrs all told for the 2 pairs. I used shop grade BB and nailed/screwed from the outside, veneering and finishing visible internal surfaces as I went, and post veneered and edge trimmed the exteriors once assembly complete.

[ranger3]

Originally Posted by chrisb

Not the simplest of builds even for a "seasoned veteran", but the plans are well detailed and fairly straightforward.

My only comments would be:

- take your time
- use the best quality high density plywood you can afford. (i.e. Apple-ply, Russian Birch, etc) - use MDF for test cuts / jigs but the Lowthers deserve far better for prime time
- if dadoing any of the internal panels via CNC or by hand made jigs, confirm thickness of materials from nominal values, and allow for variations of up to .5mm
- pre-veneer/finish as many of the visible internal panels as possible before or during assembly

The closest I've built to such a design were a couple of pairs of BLH for Coral Beta 8s and 10s. A little bit of a concern not having the rare drivers on hand to confirm tight fit in the loading chamber, but otherwise not particularly nerve-wracking, but certainly time consuming build - at least 100hrs all told for the 2 pairs. I used shop grade BB and nailed/screwed from the outside, veneering and finishing visible internal surfaces as I went, and post veneered and edge trimmed the exteriors once assembly complete.

Thank you for these suggestions and photos. Would 3/4" birch be the best choice or is their something better?

Allen...

[chrisb]

Originally Posted by ranger3

Thank you for these suggestions and photos. Would 3/4" birch be the best choice or is their something better?

Allen...

Personally, I'd stick with high ply count 3/4" birch veneer core ply ( Russian made Baltic Birch actually measures at 18mm) As I hinted at above, depending on plans for finishing of visible interior surfaces as well as the outside shell, it can be easier (if not sacrilegious to the purist cabinetmaker) to use a shop grade ply and nail / screw from the outside, then get fancy and fussy with the veneer / trim-out.

[vinylkid58]

Originally Posted by chrisb

The closest I've built to such a design were a couple of pairs of BLH for Coral Beta 8s and 10s. A little bit of a concern not having the rare drivers on hand to confirm tight fit in the loading chamber, but otherwise not particularly nerve-wracking, but certainly time consuming build - at least 100hrs all told for the 2 pairs.

Nice work! Getting to hear vintage Coral drivers in BLH's would have been very interesting.

jeff

[chrisb]

Originally Posted by vinylkid58

Nice work! Getting to hear vintage Coral drivers in BLH's would have been very interesting.

jeff

thanks - unfortunately that opportunity never availed itself

[ranger3]

What I am finding is the Medallion II plans are not exactly the same as the Medallion III+ with the addition of the tweeter.

Does anybody have a copy of the Medallion III+ plans?