# Combining 8 and 16 ohm speakers - Possible?



## Johnny Canuck (Mar 15, 2008)

Hey folks, I'm looking for a little guidance re: speakers, impedances, matching and all of that funky stuff that I really don't understand as well as I should. Note: I've searched this site and not found the answer to my particular question, so here goes ...

I have a couple of 2x12 cabs and different speakers of 8 or 16 ohm impedance. I completely understand the basics re: a pair of 16 ohms wired for a total 8 ohm load or a pair of 8 ohms for a 4 ohm load. However, I'd like to try out the various combinations of speakers to find different tones as well as which combinations of mismatched speakers work best for me. 

So here's the question: If I paired a 16 ohm Weber Blue Dog and an 8 ohm Weber California, or a 16 ohm Eminence Wizard and an 8 ohm Eminence Governor in a cab, would there be any major problems in running what I'm guessing would be a 12 ohm load? I'm looking to experiment with mismatched speakers and don't want to have to spend the $$ to buy a pack of 16 ohm speakers just to find out which combinations might work well ... so I'm looking for a way to use what I have to give me an idea of what works best with the two 16 ohm speakers I have. Once I found what I liked I'd then purchase the correct 16 ohm speaker to match and create a proper 8 ohm load.

Has anyone tried this? Any helpful hints out there? Note: Amps used to power the cabs would be tube. 

Thanks very much.

Marti K.

PS. While I'm at it has anyone tried a Weber Blue Dog/Eminence Wizard combo for Brit tones? That's an obvious option as well since I have a 16 ohm version of each. 

PPS. Here is a list of the speakers I have at hand to play with - perhaps some of you have already tried combining some of the following (all 12").

Weber:
California Ceramic 8 ohm
Thames Ceramic 8 ohm
Blue Dog Ceramic 16 ohm (100 watter)

Eminence:
Wizard 16 ohm
Governor 8 ohm
Tonker 8 ohm
Swamp Thang 8 ohm
Red White and Blues 8 ohm

Hellatone:
Hellatone 60 - 8 ohm
Hellatone 30 - 16 ohm
Hellatone 60L - 16 ohm

Reverend:
All Tone (50 watt) 8 ohm

Jensen:
C12K (100 watt) 8 ohm


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## greco (Jul 15, 2007)

I get 5.3 ohms for 8 ohms & 16 ohms in parrallel

There was a thread about this not long ago.

Cheers

Dave


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## Crowquill (Jul 4, 2008)

I depends on the amp. Come amps can handle mismatches just fine (ie mesa) and some can't. 

An 8ohm speaker and a 16ohm speaker would not give you a 12ohm load. If they're wired in series, it would be 24ohms (8+16) or, if they're wired in parallel, it would be 5.33ohms ( 1/(1/8 + 1/16) ). 5.3333ohms isn't too far from 4 ohms, so if you wire them in parallel and connect it to the 4ohms speaker jack on the amp, you _should_ be fine with _most_ amps. I would still only do it for a short time while you decide what combinations you like, then buy the proper ones


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## Johnny Canuck (Mar 15, 2008)

Thanks guys, that's really hlpful.

Dave, you wouldn't happen to recall the title of the thread would you? I tried searching on speaker impedance but couldn't find anythng on this specific topic. 

Crowquill, with respect to the amp I'd be using a Traynor YBA1 and/or a Weber Marshall kit amp. The Traynor doesn''t offer switchable impedance, just main and extension speaker outputs. The Weber/Marshall does and can easily be switched to take a 4 ohm load. However, I thought that the general rule of thumb when using amp transformer taps is to ensure that the speaker load is never HIGHER than the transformer tap. So if I wired them in parallel and got a 5.333 ohm load should I not run off the 8 ohm tap and not the 4 ohm? Or do I have it backwards? 

I just want to be sure about the right way to do this before I damage an amp or speaker. Thanks.

Marti K


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## greco (Jul 15, 2007)

This is the thread I was referring to:

http://www.guitarscanada.com/Board/showthread.php?t=16510&highlight=matching

Cheers

Dave


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## Johnny Canuck (Mar 15, 2008)

Thanks Dave!


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## Crowquill (Jul 4, 2008)

Johnny Canuck said:


> Thanks guys, that's really hlpful.
> 
> Dave, you wouldn't happen to recall the title of the thread would you? I tried searching on speaker impedance but couldn't find anythng on this specific topic.
> 
> ...


I've seen this turn into a *very * heated debate on several occasions, with people aguing both sides untill red in the face. Mesa says right in their manuals that a higher load is fine but a lower load is not BUT they're referring to Mesa amps so this logic may not be accurate for other amps with types of different output transformers...

Either way, you should always avoid a mismatch in either direction

That said if you're just doing it for a very short time just to test different speaker combos you should be fine IMO. I would use the 4 ohm out. 1.3ohms isn't a huge difference. I wouldn't run a 8ohm load from a 4ohm out but 5.3 for a short time shouldn't do any serious damage

Also, I'm fairly certain both the Traynor's outs are 8 ohms in parallel


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## Geek (Jun 5, 2007)

Crowquill said:


> I would use the 4 ohm out. 1.3ohms isn't a huge difference.


That's still nearly a 33% difference.

But it is better than putting it on the 8.

It depends on the tube and surrounding components (including the transformer) really. Higher loads causes higher voltages to appear across the the transformer primary. Some amps can take it, others can't.

Cheers!


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## Johnny Canuck (Mar 15, 2008)

Well I certainly don't want anyone to get into a heated debate over this little question. There are plenty more things to get worked up about - like politics, religion and how they get the caramel into a Caramilk bar (I know but I'm sworn to secrecy LOL!).

So the consensus seems to be to use the 4 ohm taps as long as its for a short time. I appreciate the advice and, as the saying goes, "Gentlemen, start your engines" - its off to the races.

Marti K.

PS. Now that there are woman driving on the racing circuit I guess that that phrase has had to be modified


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## Geek (Jun 5, 2007)

Johnny Canuck said:


> PS. Now that there are woman driving on the racing circuit I guess that that phrase has had to be modified


NOW here comes that heated debate..... :wink:


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## Wild Bill (May 3, 2006)

Johnny Canuck said:


> Well I certainly don't want anyone to get into a heated debate over this little question. There are plenty more things to get worked up about - like politics, religion and how they get the caramel into a Caramilk bar (I know but I'm sworn to secrecy LOL!).
> 
> So the consensus seems to be to use the 4 ohm taps as long as its for a short time. I appreciate the advice and, as the saying goes, "Gentlemen, start your engines" - its off to the races.
> 
> ...



Everybody is talking about the total speaker load and how it matches to the amp. Being a tube amp, it won't really care all that much! It will be somewhat out of its best power or distortion point on it's data sheet curves and there will be a little bit more strain on the output tubes but no big deal. Tubes are tough, after all!

However, that's NOT the important issue! What's important is how the power will end up shared between the speakers!

If you take a 16 ohm speaker and put an 8 ohm speaker in parallel with it the lower load being half of the larger means that the 8 ohm speaker will hog most of the power! The bulk of the current always flows through the lowest resistance path.

We can talk all day about the tonal combinations of adding that 8 ohm speaker but the real question is, when they are both wailing is anybody gonna hear the 16 ohm one?

Also, if both speakers are rated at 50 watts you realize what's gonna happen if you assume the pair can handle a 100 watt amp, don't you? The 8 ohm speaker will hog over 75 watts. It will likely burn out while the 16 ohm unit will never get broken in.

:food-smiley-004:


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## allthumbs56 (Jul 24, 2006)

Wild Bill said:


> Everybody is talking about the total speaker load and how it matches to the amp. Being a tube amp, it won't really care all that much! It will be somewhat out of its best power or distortion point on it's data sheet curves and there will be a little bit more strain on the output tubes but no big deal. Tubes are tough, after all!
> 
> However, that's NOT the important issue! What's important is how the power will end up shared between the speakers!
> 
> ...


S'truth. I thought I'd beef up my Princeton Reverb with my Marshall 1x12 ext cab one time and get some chunk happenin' ....... it didn't - couldn't hear the ext cab unless I put my ear right in front.

So although it's safe and each speaker will sound like itself you will have a hard time figuring out how they match together as 2/3 of the sound will come out of the 8 ohmer.


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## Johnny Canuck (Mar 15, 2008)

Drat. Thanks guys. 

Y'know I KNEW there had to be a fly in the ointment as I couldn't figure out why no one was doing it. But then I would also expect that speaker efficiency will play a role - at least with respect to the relative volume produce by each unit. Oh well, I guess I'll have to use "Noah's Law" and try them out in 2x2 matching pairs - at least as far as the impednace goes. 

I appreciate the input and advice. Thank you.

Marti K.


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