Pop
Member
Registered: 8th May 03
Location: Reading
User status: Offline
|
alright everyone ... i was looking at gettin this kit :
amp - MRDM500 Alpine D class amplifier 1 x 900w - http://www.mcs-direct.co.uk/acatalog/MCS_DIRECT_Amplifiers_49.html
sub (2x) - RFP4215 12" Punch HE2 DVC (4 ohms x 2) Subwoofer with polyypropylene cone, BART foam surround, LXursion basket, consealer gasket, Rubber magnet boot, 250 watts RMS/500 watts peak. - http://www.mcs-direct.co.uk/acatalog/MCS_DIRECT_Subwoofers_58.html
all i want to know is if it is possible to run these 2 subs off the one amp? and because they are dual coil what will the wiring look like?
thanks
tim
|
AdiSRI
Member
Registered: 1st May 02
Location: Berkshire
User status: Offline
|
no u cant.
2x 4ohm coils mean eac sub can be wired to eiter 2 or 8 ohms.
2 of those subs can then be wired to either 1 ohm, 4 ohm or 16ohm, none of which are any good.
So NO!
|
DC
Member
Registered: 24th Apr 02
Location: Grimsby, N.E.Lincs
User status: Offline
|
You need a 1 ohm stable amp for that set up mate.
Whats ya budget and some1 might just recommend ya something
|
Richie
Member
Registered: 3rd Dec 02
Location: Newport, Wales
User status: Offline
|
The closest you could get with that setup is 1.6 ohms, but lets not go there 
|
DC
Member
Registered: 24th Apr 02
Location: Grimsby, N.E.Lincs
User status: Offline
|
Agreed.
Altho if u ever good bored at some point Richie it would be good if u cud make a post explaining wiring options other than just the standard series n parallel.
Am interest even if no1 else is, lol.
|
Pop
Member
Registered: 8th May 03
Location: Reading
User status: Offline
|
yeah i'm very interested ... i've installed 2 basicish installs but this whole wiring thing and ohms is confusing the shit out of me 
|
AdiSRI
Member
Registered: 1st May 02
Location: Berkshire
User status: Offline
|
Series = Add the Resistance's together.
2 x 2 Ohm coils in series is --- 2 + 2 = 4 Ohm Load
Parallel = 1/(1/Resistance A + 1/Resistance B)
So 2 x 2 Ohm = 1 / (1/2 + 1/2) = 1 Ohm
Get it???
|
DC
Member
Registered: 24th Apr 02
Location: Grimsby, N.E.Lincs
User status: Offline
|
I obviously get all that simple stuff Adi its the wiring to dual 4's at 1.6 ohms i dont get, lol
|
Richie
Member
Registered: 3rd Dec 02
Location: Newport, Wales
User status: Offline
|
Wire one dual 4 ohm sub in series to make 8 ohm, wire the other in parallel to make 2 ohm, wire them both in parallel to the amp to make 1.6 ohms.
To work it out use this:
(Total load of speaker 1 X Total Load of speaker 2) divided by (Total load of speaker 1 + Total load of speaker 2)
|
AdiSRI
Member
Registered: 1st May 02
Location: Berkshire
User status: Offline
|
that wasnt for u DC, but for people that dont know the basics....
|
DC
Member
Registered: 24th Apr 02
Location: Grimsby, N.E.Lincs
User status: Offline
|
Thats ok Adi was just defending myself, lol.
Thanx for that Richie, makes sense and put very simply.
|
DC
Member
Registered: 24th Apr 02
Location: Grimsby, N.E.Lincs
User status: Offline
|
What about when 3 or 4 subs r involved.
Only if u hav the time tho, lol
|
Richie
Member
Registered: 3rd Dec 02
Location: Newport, Wales
User status: Offline
|
That equation is for two subs. For four 4 ohm subs you would need to use something like this:
(4 x 4) divided by (4 + 4) = 2 ohms
Then you would use the 2 ohms as one speaker in the next equation:
(4 x 2) divided by (4 + 2) = 1.3 ohms.
Then to get the total of four 4 ohm subs, you would use the 1.3 ohms as one speaker again in the next equation:
(4 x 1.3) divided by (4 + 1.3) = 0.98 ohms (1 ohm)
So the total load of four 4 ohm subs wired in parallel to the amplifier is 1 ohm.
This is the method i use anyway, any1 got summut better, test it in here 
|
