aluminum or copper voice coil?

[Haunz]

Yes, there would be a difference in mass if the coils were even somewhat similar (if they were of equal mass they wouldn't even be close)... example :

4-layer copper / 63.5mm former / 45mm WW / 7.01 ohm = 0.48mm diameter wire / ~113 grams / 67.74 mm OD
4-layer CCAW / 63.5mm former / 45mm WW / 7.06 ohm = 0.54mm diameter wire / ~40 grams / 68.19 mm OD

If we try to make them of equal mass the CCAW coil would need to be about 97mm long given a DCR close to the above (7.17 in this case).

We obviously can't make two coils using different materials the same.. so this time try to forget about DCR... The aspect I bring to the table is based on performance considering identical mass and wattage (and not DCR per say)... so lets try an aluminum coil with a corresponding larger dia. wire and overall O.D. for the same mass and wind height and see which handles more power and has the better sensitivity...


I must admit that aluminum has some advantages for SPL burping being light weight, and with it's gram for gram heat capacity.. but copper is clearly the better conductor, and is much more suited to playing music / overall abuse....

[SPLaudio]

nobody is going to disagree copper is far better the conducter.

now i hear what ur saying so it would be like a 4 layer copper against a 12layer alum to get the same weight.

the alum will win! esp cause by the time you have a 12 layer alum coil to get the mass up the gap is gonna be pretty big on that motor and the copper will be too skinny of a coil and bl will fall.
when building a sub you normally keep inmind of what coil your gonna use and build the gap for it.

i am a spl guy so i like the tight gaped subs but gapping is a whole other topic..


for a daily beater sub i choose copper for a 3sec burp sub i want alum...

[sundownz]

We obviously can't make two coils using different materials the same.. so this time try to forget about DCR... The aspect I bring to the table is based on performance considering identical mass and wattage (and not DCR per say)... so lets try an aluminum coil with a corresponding larger dia. wire and overall O.D. for the same mass and wind height and see which handles more power and has the better sensitivity...

I must admit that aluminum has some advantages for SPL burping being light weight, and with it's gram for gram heat capacity.. but copper is clearly the better conductor, and is much more suited to playing music / overall abuse....

Even for your alternate example... lets examine:

4-layer copper / 63.5mm former / 45mm WW / 7.01 ohm = 0.48mm diameter wire / ~113 grams / 67.74 mm OD

Now using the largest typically available CCAW wire :

4-layer CCAW / 63.5mm former / 45mm WW / 1.46 ohm = 0.90mm diameter wire / 66.8 grams / 70.88 mm OD

The coil is vastly different so not even comparable at all... to get somewhat comparable in mass at a given WW you would have to get into 8-layer or more flat aluminum coils (like 12-layers).

I like a good copper coil as well -- I use them in my SA series and Z v.2 series. It really is going to come down to the overall design -- one material isn't simply superior flat out, IMO. I use both materials in design based on my goals.

[Haunz]

4-layer copper / 63.5mm former / 45mm WW / 7.01 ohm = 0.48mm diameter wire / ~113 grams / 67.74 mm OD

4-layer CCAW / 63.5mm former / 45mm WW / 1.46 ohm = 0.90mm diameter wire / 66.8 grams / 70.88 mm OD

The coil is vastly different so not even comparable at all... to get somewhat comparable in mass at a given WW you would have to get into 8-layer or more flat aluminum coils (like 12-layers).

one material isn't simply superior flat out, IMO. I use both materials in design based on my goals.

Thinner dia. then .48mm copper wire is certainly available, so for a direct comparison with mass in mind, you still elude my point... I wholeheartedly agree that one material is not flat out superior to the other.. as with anything there are trades offs.. but I will always hold the view that copper is the better metal to use for a voice coil... (and I'd use silver if I could)

nobody is going to disagree copper is far better the conducter.

now i hear what ur saying so it would be like a 4 layer copper against a 12layer alum to get the same weight.

the alum will win! esp cause by the time you have a 12 layer alum coil to get the mass up the gap is gonna be pretty big on that motor and the copper will be too skinny of a coil and bl will fall.
when building a sub you normally keep inmind of what coil your gonna use and build the gap for it.

i am a spl guy so i like the tight gaped subs but gapping is a whole other topic..


for a daily beater sub i choose copper for a 3sec burp sub i want alum...

I might agree for the 3sec burp...
Just keep in mind the 4layer copper would also require a much, much, smaller gap then a 12layer aluminum...

[SPLaudio]

spl subs are ment for the loud 3 secs...

[papermaker]

It's hard to say as each woofer will have different results in nearly every app..
I know this for a fact though mass in spl isn't a huge deal because you can use huge gaps and we have retarded strong Motors as well as super stiff spiders..

The biggest factor is power compression and believe it or not the proper dampening for a given input cabin and box...
The woofer has t complement the installation..

[Kyle_Keating]

Glue a 1kg weight onto your cone and re-burp your driver. You're going lose dB in the double digits. A smaller increase in mass may be less significate, but clearly there is a linear trend to increasing mass and losing dB. One of the best ways to fight power compression is to decrease the mass. Of course at some point you decrease it so much that the driver can become suspect to damage because its weaker due to lighter/thinner parts.

[iLL Ridge]

Good reading