Adding an Ext. Speaker to my Mesa Combo

[larry_emder]

Gday from Ozstraylya all.....a friend of mine is selling a 15 inch cab that i may be interested in to go with my mesa studio .22 combo. The cab is 4 Ohms apparently.

My amp has 3 speaker outputs - 1 X 8 ohm (which the internal stock 8 ohm speaker is plugged into), and 2 X 4 ohm outputs.

If i want to run both speakers at the same time, do i:

a) Leave my internal stock speaker plugged into the 8 ohm output, and plug the 4 ohm extension speaker into the 4 ohm output.

or

b) Plug both speakers into the two 4 ohm outputs.

The manual isnt entirely clear for my situation, i'll quote it for you're benefit:

Speaker jacks:

One 8 ohm and two 4 ohm speaker outputs are provided on the Studio .22 plus. Use the 8 ohm jack when using only the internal combo speaker. Also use the 8 ohm jack for connecting an external 8 ohm cabinet (such as the boogie 4 X 12 cabinet) without the internal speaker. If using and external 8 ohm cabinet and the internal speaker, plug them both into the 4 ohm jacks. If using an external 4 ohm cabinet (such as a boogie 2 X 12), connect it to the 4 ohm jack (and preferrably disconnect the internal speaker)......

I have highlighted my situation in bold....what does 'prefferably' mean...will i do damage if i connect up both speakers????

 

[Lewguitar]

Re: Adding an Ext. Speaker to my Mesa Combo

I'm not familiar with your amp...I didn't know it was possible to plug a speaker into the 8 ohm input and a differant speaker into the 4 ohm output.

If you combine your 8 ohm speaker in your amp with a 4 ohm external speaker and plug both into the 4 ohm output, the 4 ohm cabinet will get twice as much power as the 8 ohm speaker because it has half the resistance...sort of.

The combined resistance will be less than 4 ohms.
It'll be a mismatch.

Personally, I'd look for a differant cab: one that's 8 ohms...not 4 ohms.

A 4 ohm 15" is fairly rare...are you sure about that?

Lew

 

[larry_emder]

Re: Adding an Ext. Speaker to my Mesa Combo

A 4 ohm 15" is fairly rare...are you sure about that?

Lew

Nope, not sure. Its a speaker for bass though, if that makes any difference. I'll have a look at it today

So My best bet would be to plug both in the the two 4 ohm outputs??

He's giving me a good price on it, so i'd like to be able to make it work

 

[Lewguitar]

Re: Adding an Ext. Speaker to my Mesa Combo

Nope, not sure. Its a speaker for bass though, if that makes any difference. I'll have a look at it today

So My best bet would be to plug both in the the two 4 ohm outputs??

He's giving me a good price on it, so i'd like to be able to make it work

Try it and see I guess.

But I would not combine a 4 ohm and a 8 ohm speaker.

I'd wait for a nice 8 ohm speaker cab at a good price to turn up and then combine it with the 8 ohm speaker in your amp by powering them both from the 4 ohm output of your amp.

Lew

 

[Robert S.]

Re: Adding an Ext. Speaker to my Mesa Combo

Mesa suggests if you use a 4 ohm cab, plug into the 4 ohm jack and do not use an additional cab.

You can use another valued cab but there will be a variance on your speaker impedance. You won't be off enough to hurt the amp but it does put some stress on the transformer.

The 8 ohm jack is for only one 8 ohm load. The 2 - 4 ohm jacks are paralling the speaker load of 2 - 8 ohm cabs to 4 ohms.

 

[Boogie Bill]

Re: Adding an Ext. Speaker to my Mesa Combo

You can use the extension speaker alone. But, you CANNOT use a 4 ohm extension cab with your combo's internal speaker.

If you do, it will break, and it will be EXPENSIVE.

Try to find another 8 ohm speaker cabinet. Then you can plug this cab into one of the 4 ohm jacks, and your combo's speaker into the other 4 ohm jack.

I would HIGHLY recommend a Mesa 112 EVM or C90 Theile cab with that amp.

Good Luck!

Bill

 

[larry_emder]

Re: Adding an Ext. Speaker to my Mesa Combo

Well i tried it and it didnt break. And i bought both his 15' cabinets for a STEAL.

But They were both fairly quiet compared to my internal speaker (i assume this was due to the impedance mismatch? and the 15' 'ers are probably not the most efficient.
I will buy an 8 ohm 15' speaker for one of the cabinets so i can run it with the internal speaker without worrying too much

Now for 15' speaker suggestions...i want something that will compete in volume with the internal speaker...