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Topic: Choosing a speaker: 8 ohms or 4 ohms? |
Alex Cattaneo
From: Quebec, Canada
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Posted 7 May 2014 5:02 am
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So amps have more output when you present them with a 4 ohms speaker. Unless it's a tube amp and you want the correct resistance, why would you ever want to use an 8 ohms speaker? If a 4 ohms speaker is louder, than it's a pretty obvious choice, no?
I'm obviously woefully ignorant when it comes to technical stuff so I'm hoping you guys can help me out. I'm putting together a 12" cab to use with either a Genz Benz Shuttle 3.0 head, a Nashville 400 head, or any other amp head I might be tempted to acquire later.
The Genz Benz is rated 175W/8 ohms; 300W/4 ohms
The Nashville 400 is rated 130W/8 ohms; 220W/4 ohms
So, using an 8ohms speaker almost divide by two the power I can get from my amps, hence I better go 4 ohms. Am I right?
Thanks! |
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Donny Hinson
From: Glen Burnie, Md. U.S.A.
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Posted 7 May 2014 7:43 am
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Most steelers using 200-300 watt amps never exceed 50-75 watts when they play. "Maximum power" is with everything full-on, and most players don't play like that very often. |
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Jim Cohen
From: Philadelphia, PA
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Bill Duncan
From: Lenoir, North Carolina, USA
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Posted 7 May 2014 8:17 am
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I would say maybe half a hill or less. _________________ You can observe a lot just by looking |
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Dave Grafe
From: Hudson River Valley NY
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Posted 7 May 2014 8:31 am
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As the power from a solid state amp when driving alower impedance the damping factor - which is the amp's ability to control cone over-excursion - goes down. Essentially, buy using a lower impedance speaker we increase the power at the expense of tight low end response. |
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Alex Cattaneo
From: Quebec, Canada
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Posted 7 May 2014 8:58 am
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Interesting. So Dave (and anyone else), which would you choose and why? |
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Bill Duncan
From: Lenoir, North Carolina, USA
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Posted 7 May 2014 9:23 am
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If I was buying new, or reconing, I would get what my amp was rated at. I've run 8's and 16's in a Vegas 400, and I could tell a little difference in volume, not too much in tone though. I think the type and brand, such as Altec, JBL, EV, BW, etc. makes more of a tone difference than ohms. _________________ You can observe a lot just by looking |
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David Higginbotham
From: Lake Charles, Louisiana, USA
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Posted 7 May 2014 9:47 am
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Echoing what Donny said, but adding that an 8 ohm speaker gives you more flexibility if you want to add an extension speaker and if you run a power amp bridged. Most require an 8 ohm load with the exception of Stewart power amps.
Dave |
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Scot Buffington
From: North Carolina, USA
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Posted 7 May 2014 11:31 am
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In about 1998, we switched from installing 4 ohm to 8 ohm speakers in Evans Combo amps and speaker cabinets. Since then, some people have changed the 8 for a 4 ohm speaker and vice versa. Having the right speaker for your application and sonic preferences can make a big difference in your amplified sound. You may want to consider how a 4 or 8 ohm speaker can effect your tone.
All things being equal, the 4 ohm has to handle about twice the current of the 8 ohm speaker. This requires a thicker cone and larger voice coil wires. The extra power handling ability produces a good low end and midrange punch. However these gains are offset by less upper end clarity and warmth.
Another consideration is the difference in volume. You can get a idea how loud a speaker is by noting the SPL rating. For example: an 8 ohm, 98 dB SPL speaker produces about the same volume as a 4 ohm, 92 dB SPL speaker.
Also, remember that the 4 and 8 ohm ratings are nominal and measured at one frequency. A speaker rated at 8 ohms can have an actual impedance of 4 to 8 ohms. A 4 ohm speaker can have an actual impedance
of 2 to 4 ohms. Given that there is little difference difference between 2 ohms and a dead short on an amp's output, the 8 ohm speaker may better prevent premature amp failure from thermal runaway.
In conclusion, most of the time a 4 ohm speaker will provide better Bass response and dynamics. It also follows that an 8 ohm speaker will consequently sound warmer and provide better upper end clarity and amp reliability.
At this time, new Eminence Beta speakers are my personal favorite.
This is just my opinion based on two decades of amp building experience. I don't mean to suggest that other people should adopt it. |
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Donny Hinson
From: Glen Burnie, Md. U.S.A.
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Posted 7 May 2014 4:28 pm
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Jim Cohen wrote: |
So, Donny, is your point that it doesn't make a hill of beans difference? |
Well, it's sorta like that, Jimbeaux. As my Pappy used to say..."More is what you want, but enough is all you need". |
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Lane Gray
From: Topeka, KS
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Posted 7 May 2014 4:42 pm
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The thing I've gleaned from this thread, and someone correct me if I got it wrong, the 4 is like the humbucker and the 8 akin to the single coil: sure the former has more output, but the latter has a more pleasing output.
Or, for the Top Gear analogy: 4 ohms=Clarkson, 8 ohms=May _________________ 2 pedal steels, a lapStrat, and an 8-string Dobro (and 3 ukes)
More amps than guitars, and not many effects |
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Dave Potter
From: Texas
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Posted 7 May 2014 5:36 pm Re: Choosing a speaker: 8 ohms or 4 ohms?
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Alex Cattaneo wrote: |
So amps have more output when you present them with a 4 ohms speaker. Unless it's a tube amp and you want the correct resistance, why would you ever want to use an 8 ohms speaker? If a 4 ohms speaker is louder, than it's a pretty obvious choice, no?...using an 8ohms speaker almost divide by two the power I can get from my amps, hence I better go 4 ohms. Am I right? |
Well, I'm surely no electronics wizard, and those who are will spank me righteously if I'm wrong, but I know a little about this, just enough to be dangerous.
First thing I'd recommend would be to understand the difference between resistance and impedance. Speaker ohms are rated as impedance, which is not the same thing as "resistance".
Unless you get into special cases like "bridging", final amplifier stages are designed for specific impedance loads, and using something different can lead to issues, is how I understand things. |
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Joe Naylor
From: Avondale, Arizona, USA
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Posted 7 May 2014 7:02 pm what I have found
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Well since I have been building Seat-Amps my opinion is the Hill of Beans statement is correct.
I had someone play on at the Dallas show that was a 4 ohm speaker and he went on and on about how great that that speaker was and that the 8 ohm and blah blah blah blah - I just listened and knew he did not know what was actually going on.
I do know most have an opinion but many times it is one of those bigger numbers are better no matter what the sound. Even comparing amps.
I told a guy that I was going to advertize 16 or 32 ohms just to say "my dog is bigger than your dog" but of course I will not miss represent but it was a funny thought.
Joe Naylor
www.steelseat.com _________________ Joe Naylor, Avondale, AZ (Phoenix) Announcer/Emcee owner www.steelseat.com *** OFFERING SEATS AND Effects cases with or without legs and other stuff ****** -Desert Rose Guitar S-10, Life Member of the Arizona Carport Pickers Assoc., Southwest Steel Guitar Assoc., Texas Steel Guitar Assoc., GA Steel Guitar Assoc., KS Steel Guitar Assoc. (Asleep at the Steel) tag line willed to me by a close late friend RIP
Last edited by Joe Naylor on 7 May 2014 7:05 pm; edited 1 time in total |
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Jim Cohen
From: Philadelphia, PA
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Posted 7 May 2014 7:05 pm Re: what I have found
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Joe Naylor wrote: |
...many times it is one of those bigger numbers are better no matter what the sound. Even comparing amps. |
Well, I know my amp is better, because it goes up to "11"! _________________ www.JimCohen.com
www.RonstadtRevue.com
www.BeatsWalkin.com |
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Joe Naylor
From: Avondale, Arizona, USA
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Posted 7 May 2014 7:08 pm more
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Well Jim I will make one that goes to 25
But it is about that funny. If your speedometer in your "Smart Car" goes to 200 mph I am not sure you will ever go here.
Jim I think we have discussed this before .......... Common Since is not so Common all the time
Joe Naylor
www.steelseat.com _________________ Joe Naylor, Avondale, AZ (Phoenix) Announcer/Emcee owner www.steelseat.com *** OFFERING SEATS AND Effects cases with or without legs and other stuff ****** -Desert Rose Guitar S-10, Life Member of the Arizona Carport Pickers Assoc., Southwest Steel Guitar Assoc., Texas Steel Guitar Assoc., GA Steel Guitar Assoc., KS Steel Guitar Assoc. (Asleep at the Steel) tag line willed to me by a close late friend RIP |
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Jimbo Watkins
From: Allen, Texas, USA
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Posted 8 May 2014 4:46 pm
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Scot,
There are three models of the Eminence Beta 12". The 12A2', the CX and the LTA. Which one is it that you are using? Thanks . . . . _________________ It's only a flesh wound! |
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Scot Buffington
From: North Carolina, USA
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Posted 9 May 2014 4:22 am
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Thanks for your question. I use the Beta 12 A2 with Evans 200 Watt amps and speaker cabinets. I believe that they are rated at 300 W. For 500 W combo amps and speaker cabinets, I install a Delta 12 A.
The other Beta and Delta speakers that we stock are 10 A and 15 A.
The Beta speakers are sweeter sounding at low to medium high volumes and the Delta speakers sound better at very high volumes and bass levels. I recommend that you try the Beta speakers, unless you mostly play at really loud volumes. Thanks again. |
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