Speaker impendence matching question

[jazzedout]

I have a Laney LC15R with an internal speaker rated at 8 Ohm. It also has an external speaker jack and it states that you could use either 8 or 16 Ohm speakers. Does this mean that I can also replace the internal speaker with a 16 Ohm one, or is there a different cirquit involved with the external speaker jack?
Thanks!

[EvoGiant]

if they put in an 8 ohm, you should replace it with an 8 ohm. a 16 ohm isnt going to give you anythin over an 8 ohm. a 16ohm may actually lower your output power because its twice the resistance on the amp. as far as the speaker out jack, grab the book and read up. you probably will get different power ratings out of it at different impedances.

[jazzedout]

The only reason to put a 16 ohm speaker, is that I have one spare that I'd like to test. The manual states that you can put either 8 or 16 ohm speakers on the speaker out jack, but doesn't state anything about its effect on power, or if you can hook a 16 ohm one internaly or not. Thant's why I am asking.

[martyfriedman86]

I beleive the LC15r is a 2x6bq5 tube amp

the output transformer should have separate taps on the secondary usually wired to a rotary switch that let's you select the the correct tap for the desired impedance load you will be using.

if you have no such switch, and only a speaker out meant to be used with both 8 or 16 ohms speakers, you could get a digital multimeter/resistance meter, and check if the speaker out is connected to the same wires as the speaker in the amp, if it is, you're safe to try a 16 ohms speaker in the amp. at least according to your manual.

I beleive the amp might be designed for 8 ohms, and it will be ok to put a 16 ohms/speaker cab on it, without making any damage to the amp, BUT you'll get less volume because of impedance mismatch, and it can also sound kinda dull, less rich.

I hope this helps.
Sorry for my english, i'm not a native speaker.