# Ohms?

Discussion in 'Amps and Cabs [BG]' started by Obsolex, Apr 2, 2003.

1. ### ObsolexGuest

Nov 17, 2002
Ok i know the meaning of ohms, 4ohms, 8ohms, ect... But what are they, like, is a 400 watt amp at 8 ohms, louder than an 800 watt amp at 4ohms? thanks, _-soto-_

Apr 30, 2000
Melnibone
No.

3. ### ObsolexGuest

Nov 17, 2002
thanks, well that helps, lolz, _-soto-_

4. ### Lockout

Dec 24, 2002
Illinois
Yeah, Turock is right... a watt is a watt no matter what, basically.

5. ### ObsolexGuest

Nov 17, 2002
WHAT IS AN OHM! lolz, _-soto-_

6. ### As the sun setsGuest

Dec 10, 2002
N. Easton, MA
Yes, a watt is a watt.

The higher the Ohm number, the more impedence the cab has. Meaning.. If you have an 800-watt amp, it will be louder if you run it into a 4-ohm cab rather than an 8-ohm. The 4-ohm cab has a lower impedence, meaning it lets the amp run more power into it. The 8-ohm has a higher impedence (hence the higher number), so it lets less power into it, meaning it's not as loud. Having two 8-ohm cabs is ideal in most cases because the impedence equals out to 4 Ohms. Anything lower than 4 Ohms can be kind of dangerous. 2 Ohms can work, but it's risky in my opinion. Again, a watt is a watt. It all depends on the impedence.

7. ### ObsolexGuest

Nov 17, 2002
thanks man, _-soto-_

8. ### As the sun setsGuest

Dec 10, 2002
N. Easton, MA
No problem. Hope that cleared some things up for you. Basically, impedence = resistance. Higher impedence/resistance = less volume.

9. ### Petebass

Dec 22, 2002
QLD Australia
Not really. Less Watts for sure, but the actual volume drop is barely noticable.

Try this run a bass amp through a single 8 ohm cab. Then run it through the same cab but in a 4 ohm version. The volume benefit is barely noticable, you have however created more headroom in the amp.

In reality most people go from 8 ohms to 4 by adding a second cab. The volume increase here is largely due to having twice as many speakers pushing air.

The smallest volume jump the human ear can hear is 3db. To get an extra 3db, you have to double your watts. To Double your volume (10db), you need to multiply the watts by 10. Db is a logarithmic scale.