Different type of ohmage question

[vander]

I searched impedance threads and google but could not find this info.
I have been researching for the purchase of one 4x12 cabinet for my hundred watt head. The head has a selector switch for 4,8 or 16 ohms so I could match any speaker impedance I ended up with.
My question is does the impedance make a volume difference or operational difference. IE...If I could choose between 8 or 16 ohms in the same cab is there a reason I should choose one over the other? Will the 8 ohm be louder because of less resistence or does the impedance selector offset that. Will less or more impedance be less stressfull on the tubes?
Thanks for any insight you might have,

[Dreamland_Rebel]

Re: Different type of ohmage question

is there a sound difference? yes, slightly, but the main reason for a selector is to match the output resistance with the load resistance.

the sound difference is very slight if any at all. the main idea is not to have the load resistance lower than the output resistance. so 16ohm cab into a 8ohm out won't hurt it too bad. but the safest bet is to match the impedence.

REMEMBER: when running two cabs on a mono head the impedence is cut in half. ---> two 16ohm cabs = one 8ohm load on the head.

[thetroy]

Re: Different type of ohmage question

As I understand it...Lower impedence will be louder and thus more stressful on the tubes

[vander]

Re: Different type of ohmage question

Thanks for your response...I guess I should clarify that when I say choose between 8 or 16 ohms in the same cab I don't mean switch a selector...I mean buy a cab wired for 8 ohms or buy a cab wired for 16.

[Dreamland_Rebel]

Re: Different type of ohmage question

you shouldn't even bother worrying about that. just buy a cab that sounds good to you and hook it up properly.

[horns666]

Re: Different type of ohmage question

[ QUOTE ]
you shouldn't even bother worrying about that. just buy a cab that sounds good to you and hook it up properly.

[/ QUOTE ]

Exactly!!!

I do notice a slight difference in sound when I run my Uber and my old 5150s at 4 Ohms..they sounded a tad better to my ears..but the amp and cab was set to 4 Ohms..but two 8 ohms cabs would = 4ohms..just like Dealand Rebel stated.

[Cleveland Metal]

Re: Different type of ohmage question

I'm the same way.

For some reason, (if you have the choice to match the cab and head impedance at different impedances) that setting my amps at the 4 ohms sounds better to my ears than the 8 or 16 ohms settings. Not sure why.

No volume difference that I know of "if" you are matching the impedances. The reason people may think that is that unswitchable impedance solid state PA power amps will often state power at 250 watts into 8ohms and 400 watts into 4 ohms etc. I don't think that applies to tube heads.

[horns666]

Re: Different type of ohmage question

Wow John, you know I don't think we ever actually discussed this..or did we.

see great ears think alike! [img]/images/graemlins/wink.gif[/img] [img]/images/graemlins/tongue.gif[/img]

John and I are sooo in tuned to similair tones..it's just sick...well we been together for hell..well over 20 years..and we love the same stuff...pretty damn much.

we were weened on the same stuff that's for sure!