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Ohms and stuff

PostPosted: Sat Jan 21, 2012 4:17 pm
by jetcross
I have a 300w 4 ohm amp and 2 x 400w 8ohm cabs which is fine. Is it possible to use just one cab with the amp ? I would welcome any advice as I don't want to damage the amp or cabs. Thanks ~ Ian.

Re: Ohms and stuff

PostPosted: Sat Jan 21, 2012 5:11 pm
by rogera
Using just one of the 8 ohm cabs with the amp is perfectly safe (as long as the internal 4 ohm speaker of the amp is then disconnected).

The amp will be happy with that, but the output of the amp will be reduced.

Re: Ohms and stuff

PostPosted: Sat Jan 21, 2012 5:44 pm
by Jay Bass
jetcross wrote:I have a 300w 4 ohm amp and 2 x 400w 8ohm cabs which is fine. Is it possible to use just one cab with the amp ? I would welcome any advice as I don't want to damage the amp or cabs. Thanks ~ Ian.



The 4 ohm rating on the amp is the minimum rating ohms
( dont go below this ,2x 4 ohm cabs would run at 2 0hms and cause damage)
using 2 8 ohm cabs means you are running the amp at 4 ohms
and getting the full 300w power of the amp
if you run just 1 x 8 ohm cab you will get approx 210w of the 300w
should be fine i do a similar thing with rehearsals ,it saves humping around loads of gear.

Regards
Jay

Re: Ohms and stuff

PostPosted: Sun Jan 22, 2012 9:26 am
by RayL
In post #1 Ian doesn't actually say whether he has a valve or a solid-state amp. Replies #2 and #3 are correct for solid-state, but if it happened to be a valve amp (ie with an output transformer) it's not quite so clear-cut. However, 300w valve bass amps are fairly unusual (because of the weight) so solid-state is a good asumption.

Ray

Re: Ohms and stuff

PostPosted: Sun Jan 22, 2012 1:30 pm
by jetcross
Many thanks for your replies. The amp is a Trace-Elliot as are the cabs. Cheers ~ Ian.