I spent a lot of time hand wringing over making "the lightest cab" possible, sourcing a supply of spruce ply over birch (partly because I found no reasonably priced birch ply within a 30 mile radius, too).
Out of interest, I asked over on another board where there is BFM "action" for a weight of a measured piece of birch ply. I then measured and weighed a bit of my spruce ply.
Here's the results:
Using a rough calc based on that and my weighing of a spruce offcut, I make the birch ply to be 0.78 g/cm2, spruce 0.66g/cm2.
So to get a rough weight multiply the area in square cm by 0.78 (birch) or 0.66 (spruce) to get the weight in grams.
So an 8x4' sheet of birch will weigh 22.4kg, and the same in spruce will weigh 19kg.
If you want to work in inches and lbs, then the birch is 0.178 Oz/inch2, spruce 0.15 oz/inch2. So multiply your area in square inches by 0.178 (birch) and 0.15 (spruce) to get the weight in ounces.
Obviously this is all very rough, but it suggests that there is just over 2kg difference between a spruce and a birch OT12 - not a huge difference!
I guess if you're doing a bigger cabinet then the difference in weight would add up a little more, but it's certainly not as significant as I had led myself to believe.
Had I known that I don't think I would have worried so much about sourcing the lightest ply - and I've not found a local source of birch (albeit expensive).
Worried about the weight of birch vs softwood ply? Don't!
Here are some real world examples. Both comparisons use the same finish, hardware, and drivers.
Wedgehorn, Baltic Birch, 25lbs.
Wedgehorn, 5-ply A/C, 20.5 lbs.
That's 4.5 lbs for the smallest cabinet on the site.
Tuba 24 16", Baltic Birch, 56lbs.
Tuba 24" 18", 5-ply A/C, 45lbs.
That's 11lbs. lighter and a wider cabinet.
Baltic Birch is heavy. Is it better? I have noted absolutely no difference in performance. The Baltic will hold up to rough handling better, it's much harder and will take bumps with fewer nicks and scrapes.
So, what's your pleasure? If you have a bunch of apes handling your gear or do rentals, go with Baltic. If you handle them yourself or there's a specific group of people (your own band) then you can regulate the handling. I prefer light, but I'm old.
Wedgehorn, Baltic Birch, 25lbs.
Wedgehorn, 5-ply A/C, 20.5 lbs.
That's 4.5 lbs for the smallest cabinet on the site.
Tuba 24 16", Baltic Birch, 56lbs.
Tuba 24" 18", 5-ply A/C, 45lbs.
That's 11lbs. lighter and a wider cabinet.
Baltic Birch is heavy. Is it better? I have noted absolutely no difference in performance. The Baltic will hold up to rough handling better, it's much harder and will take bumps with fewer nicks and scrapes.
So, what's your pleasure? If you have a bunch of apes handling your gear or do rentals, go with Baltic. If you handle them yourself or there's a specific group of people (your own band) then you can regulate the handling. I prefer light, but I'm old.
I'm with Tim on the light end. The whole reason I am replacing my old worn out horn system is because of the weight. We have a Midliner Diesel to haul just about anything in and loading in 8 200+ Lb. Keales along with Community M80 Mids and Martin (JBL Loaded) tops is no joy.
While the sound of the old system is typical horn loaded sound it's still pretty good but Bills designs are a cut above in clarity and usable output along with a large reduction in weight and frontal area along with pack space.
Pack space really isn't an issue as we still haul the old gear just in case.
Weight is a real big factor once you start getting older and especially if you're trying to keep the costs down by not using stage hands for load-ins. It also allows us to be more competitive when it comes to pricing. Less labor means more dollars for me and lowers the insurance worries when it comes to other people moving our stuff around.
Back in the 80's we used to spec a fork truck on site when loading in the old RCA Ubangis and Community Leviathans. These puppies are well over 400Lbs per box and we used 6 of them. The Keales were a God send in terms of weight compared to the double 15" Ubangis and Levis.
While the sound of the old system is typical horn loaded sound it's still pretty good but Bills designs are a cut above in clarity and usable output along with a large reduction in weight and frontal area along with pack space.
Pack space really isn't an issue as we still haul the old gear just in case.
Weight is a real big factor once you start getting older and especially if you're trying to keep the costs down by not using stage hands for load-ins. It also allows us to be more competitive when it comes to pricing. Less labor means more dollars for me and lowers the insurance worries when it comes to other people moving our stuff around.
Back in the 80's we used to spec a fork truck on site when loading in the old RCA Ubangis and Community Leviathans. These puppies are well over 400Lbs per box and we used 6 of them. The Keales were a God send in terms of weight compared to the double 15" Ubangis and Levis.
Ever since I replaced sex with food I cant even get into my own pants!
I'm all for light weight, so much so I internet ordered a whole bunch of Poplar Ply in 2' x 4' panels, for my next build. I took some measurements a while ago and found 1/2" BB works out to 50 lbs per 4' x 8' sheet, and the poplar 40 lbs per 4' x 8' sheet.
Tomorrow I'm going to stop procrastinating - WB
It was baltic birch.
From the comments in this thread, and the example weights, I'm actually changing my position back towards there being a noticeable difference in "real world" weight of cabs built in spruce vs birch. I guess it depends on the cab and the amount of timber going in to it, of course.
With the spruce wedgehorn I made, I tried applying a coat of the wood hardener you get to treat wet rot. While this didn't seem to make the timber much more resistant to dings (I did a trial on a test piece with a hammer
), it does seem to have helped me get a good finish with the TuffCoat paint.
From the comments in this thread, and the example weights, I'm actually changing my position back towards there being a noticeable difference in "real world" weight of cabs built in spruce vs birch. I guess it depends on the cab and the amount of timber going in to it, of course.
With the spruce wedgehorn I made, I tried applying a coat of the wood hardener you get to treat wet rot. While this didn't seem to make the timber much more resistant to dings (I did a trial on a test piece with a hammer
), it does seem to have helped me get a good finish with the TuffCoat paint.