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Are there many HiFi speakers with nominal 4 ohm impedance?

roog

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Just curious I suppose. I have been looking for amplifiers that will deliver around 100W into an 8 ohm load and yet most amps power are quoted in to 4 ohms.

I get it, from a marketing perspective it makes the amplifier sound like its 'better' i.e. more powerful, but it got me wondering whether there are really that many speakers which present as nominal 4 ohms?
 
it got me wondering whether there are really that many speakers which present as nominal 4 ohms?
Yes, there are.

A majority, even:
Screenshot_20241203-182628_Chrome.png
 
For a speaker to qualify as nominal N ohms, its minimum impedance must not dip below 0.8*N ohms. As it turns out, "8 ohm" speakers with 3.2-ish ohm minima aren't exactly rare. Such creative specsmanship has thankfully become less common in more recent times as measuring an impedance response doesn't take too much these days, but it was a regular occurrence well into the 2000s at least. I guess it was one way to (a) make your speakers look more sensitive and (b) not scare amplifier / receiver owners.
 
Just curious I suppose. I have been looking for amplifiers that will deliver around 100W into an 8 ohm load and yet most amps power are quoted in to 4 ohms.

I get it, from a marketing perspective it makes the amplifier sound like its 'better' i.e. more powerful, but it got me wondering whether there are really that many speakers which present as nominal 4 ohms?
There are many 4 Ohm -speakers out there. The German DIN -Norm 45500 allows a speaker with nominal 8 Ohms to go as low as 6.4 Ohms and a 4 Ohm speaker may get as low as 3.2 Ohms somewhere within the range from 20 Hz- 20.000 Hz.
Speaker builders have to sell a speaker which reaches 3.1 Ohm as a Minimum in Germany as a 2 Ohm speaker. Otherwise they are not allowed to sell it.
It is not wrong to buy a speaker which feels "happy" with 4 or even 2 Ohms. Stability is not at all a bad thing ;) .
 
4 ohm speakers appear to be common for PA (or at least they were, since most new ones are active) and the ones I have in my gym setup are 4 ohm but sometimes dip below even that. I'd say they're more common than 8 ohms because it allows (or allowed with older designs) for more amp power.
 
There are many 4 Ohm -speakers out there. The German DIN -Norm 45500 allows a speaker with nominal 8 Ohms to go as low as 6.4 Ohms and a 4 Ohm speaker may get as low as 3.2 Ohms somewhere within the range from 20 Hz- 20.000 Hz.
Speaker builders have to sell a speaker which reaches 3.1 Ohm as a Minimum in Germany as a 2 Ohm speaker. Otherwise they are not allowed to sell it.
It is not wrong to buy a speaker which feels "happy" with 4 or even 2 Ohms. Stability is not at all a bad thing ;) .
DIN 45500 was replaced by EN 61305 in 1996.

And where do you have this "can't be sold in Germany otherwise" from? The infamous Infinity Kappa 9 for example dipped down to 0.8 Ohm, and was therefore a nominal 1 Ohm speaker - but still sold as 4 Ohm nominal in Germany.
 
DIN 45500 was replaced by EN 61305 in 1996.

And where do you have this "can't be sold in Germany otherwise" from? The infamous Infinity Kappa 9 for example dipped down to 0.8 Ohm, and was therefore a nominal 1 Ohm speaker - but still sold as 4 Ohm nominal in Germany.
new????
 
Yes, there are.

A majority, even:
View attachment 411229

Wow, I really didn’t know, all of the speakers I have owned have been 8 ohm declared.

I remember my local hifi dealer steered me away from one particular brand citing their 4 ohm nominal impedance, I spent 5 mins browsing my local dealers web site and very few showed up as 4 ohm. Hence the question, I shall be checking in future just for fun.
 
4 ohm speakers are common as are amplifiers that will power them just fine. No reason not to use a 4 ohm speaker if it fits your needs. It is essentially a non-issue.
 
It's complicated, 4 or 8 ohms on it's own doesn't mean that much. You have to look at the entire curve. It's the lowest dips and the phase angle at those dips that determines just how difficult a load your speaker will be on your amp. Here check this out:


Rob :)
 
Utter nonsense, IMO.

That has been the case for several decades, for sure, but in the 1950s, 1960s, and 1970s, Speakers were either 16R or 8R and 4 ohm was extremely rare, if sold at all. Amplifiers were designed to current limit a lot more than today and a 4R load on even some early 1980s amplifiers would trip either OC or current limiting.

Amplifiers were designed to swing big voltages- a hangover from the tube days.

The dealer was probably an old skool dealer who had experienced trouble in the past.
 
That has been the case for several decades, for sure, but in the 1950s, 1960s, and 1970s, Speakers were either 16R or 8R and 4 ohm was extremely rare, if sold at all. Amplifiers were designed to current limit a lot more than today and a 4R load on even some early 1980s amplifiers would trip either OC or current limiting.

Amplifiers were designed to swing big voltages- a hangover from the tube days.

The dealer was probably an old skool dealer who had experienced trouble in the past.

Could be, I recall Bang and Olufsen producing 4 ohm speakers.

Of course car stereo systems have been 4 ohm since I can remember due to the voltage limitations in early radios and car stereo.
 
Could be, I recall Bang and Olufsen producing 4 ohm speakers.
Which makes sense as these were very common here on the ol' mainland. Pretty much the entire West German loudspeaker industry was 4 ohm territory even in the '70s... Braun (a/d/s), Canton, Elac, Grundig, Heco... Likewise, domestically produced amplifiers and receivers generally were relatively modest affairs geared towards 4 ohm speakers.
 
I think that the loudspeaker industry* just likes being able to claim 3 dB more sensitivity without doing any actual work. :rolleyes: :cool: ;)

______________
* i.e., Big Loudspeaker ;)
 
Which makes sense as these were very common here on the ol' mainland. Pretty much the entire West German loudspeaker industry was 4 ohm territory even in the '70s... Braun (a/d/s), Canton, Elac, Grundig, Heco... Likewise, domestically produced amplifiers and receivers generally were relatively modest affairs geared towards 4 ohm speakers.
Indeed. And pretty much all of these companies were (and still are) kinda infamous for being "generous" with their specifications - no doubt for marketing purposes. A "4...8 Ohm" rating for speakers is very common for example, which basically means it's a nominal 4 Ohm speaker - and sometimes not even that, as they don't tend to adhere to the 20% convention. You could and can very well buy speakers with minimum impedances of 3 Ohm, and they'll still say "4...8".

Same with frequency responses. The -10dB figure seems to be very popular, which is why you can find a bunch of 8" bookshelf speakers rated 25-30000Hz for example. Of course their spec sheets never say whether that's -3, -6 or -10dB. :eek:

Verdict: read German specs with caution. They aren't direct lies usually, but intentionally misleading in order to look great. If in doubt, assume the least flattering figure. :D
 
looking for amplifiers that will deliver around 100W into an 8 ohm load and yet most amps power are quoted in to 4 ohms...are really that many speakers which present as nominal 4 ohms?
- This loudspeaker engineer who was drafted into Marketing whoredom says speaker specs are useless twaddle. Total crap.
- "8 ohm" speakers are pretty much all lying and really "4 ohms" if you look at actual tests at https://www.stereophile.com or here. 4Ω makes the speaker more efficient, but makers want to say 8Ω because receivers are not rated into 4Ω. And yes impedance is more complicated, but the principle still applies. --> The important power spec is the 4Ω or better yet 2Ω spec because this implies how much current the amp can deliver.
- Do amplifiers deliver more power into 4Ω? Eh, maybe. Per a conversation with the managing director of amplifier design for a $3B company I worked for, it's all about the current, not the power. OK, a lot of sake was involved, and he did not speak a lot of English but that's what the translation service called "cocktail napkin drawings and lots of gestures" is for. From amplifier testing I did my belief is that loading down amplifiers does NOT generate much more short-term peak power at all, while definitely generating more waste heat and drawing more current from the car battery or wall. This may seem contradictory to the previous point; I guess it is more directed at DIY subwoofers where folks want to load the amp to a low impedance to try and get more power.
 
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