# Whats louder?

Discussion in 'Amps and Cabs [BG]' started by Wxp4759cb, May 25, 2002.

1. ### Wxp4759cb

Nov 23, 2000
Kansas City, MO
750 watts @ 4ohms, is louder than 500watts @ 8 ohms right?

2. ### MunjibungaTotal Hyper-Elite MemberGold Supporting Member

May 6, 2000
San Diego (when not at Groom Lake)
Independent Contractor to Bass San Diego
You are correct, sir, all other things being equal.

3. ### chucko58

Jan 17, 2002
Silicon Valley, CA, USA
I paid for all my gear myself. Well, me and MasterCard.
Both those ratings could come from the same amp! So in fact one might not be louder than the other - with the same 8 ohm cab, anyway.

4. ### jokerjkny

Jan 19, 2002
NY / NJ / PHL
Aint the layman's formula, if there's less ohms to push, the more wattage you can pump out? so, thusly should be louder, no?

5. ### BillyB_from_LZSupporting Member

Sep 7, 2000
Chicago
The power difference between those two ratings is so small that you probably won't hear a volume difference assuming that the two cabinets are other wise equal.

I believe that the rule of thumb is that it takes twice the power to increase SPL by 3 dB which is the smallest volume change that humans can generally hear (yes, there are exceptions).

And, said amp would certainly run hotter at 4 ohms than at 8...which isn't a good thing.

6. ### Wxp4759cb

Nov 23, 2000
Kansas City, MO
Well I currently have an 8ohm goliath III. It still has 25 days to return it. My power amp puts out 500 watts at 8 ohms, or 750 at 4 ohms. Adding another cab latter will not give a 4 ohm load b/c the amp uses 2 seperate channels. Should I switch the cab for the 4 ohm (free), or keep the 8 ohm.

7. ### Sanctum

Jan 25, 2002
Conjunction Junction
You should buy 3 more 8ohm cabs

Greg

8. ### MunjibungaTotal Hyper-Elite MemberGold Supporting Member

May 6, 2000
San Diego (when not at Groom Lake)
Independent Contractor to Bass San Diego
If you daisy-chain two 8-ohm cabs, you'll have four ohms. In answer to your question, if you don't plan to add any more cabs, definitely (note correct spelling) swap for the 4-ohm.

9. ### BFunkModeratorStaff MemberSupporting Member

Adding another cab will increase the real and percieved volume much more than having a single 4 Ohm cab. The sound will not only be 3+ Db louder with the second cab, but it will sound fuller and spread more. (Remember sound is about moving air. More speakers mean more air gets moved.) The down side is that you have more cab to take to the gig.