Understanding 4-8 Ohm Speakers: Impedance, Amplifier Compatibility, and Selection Guide

Question

Hello, as in the subject. What's with the speaker impedance from 4 to 8 ohms. I have an amplifier for which I would need 4 ohm speakers to get more out of it and I don't know if I buy such speakers, whether they will work at 4 or 8 ohms. Please help.

http://www.jednostki.adgraf.net/ Please don't cut your tongue. [P.]

Pablo1964 · Answer

The impedance of the columns is not a constant value, but changes as a function of frequency.

Kur-Czak · Answer

The nominal impedance of the loudspeakers is given for f = 1 kHz and, as my colleague wrote, it changes with the frequency.

Luke15 · Answer

Simply put, each speaker has a specific impedance that depends on many other factors (but that's not important at the moment). Now, looking at the parameters of the amplifiers, you can see that the power output is the greater the lower the impedance for which the measurement was made. For example, an amplifier that is able to deliver 200W when loaded with a speaker with an impedance of 4R, for an 8R speaker will give approximately half of this power, i.e. about 100W, because the impedance is 2x higher - simple, right? ;) However, each amplifier also has the highest possible load capacity for the channel, at which it works stably, and should not be exceeded because you may damage the amplifier in this way. If you want to get as much out of the amplifier as possible, load it as much as possible (i.e. with the minimum allowed impedance) because it will give the greatest power. It's just like that. greetings

AnTech · Answer

When it comes to the loudspeaker's nominal impedance, my colleague is not true. I refer to literature. When designing the amplifier, the designer assumes its operation with typical loudspeakers with specific nominal impedances. In this case, 4 ? or 8 ?. 4? is the minimum nominal impedance of the connected loudspeakers. The amplifier can work with 8? speakers without any harm. Of course, it can also work with loudspeakers of even higher impedance, but such speakers are rarely found in the trade. The description on the amplifier indicates which speakers you can use with this amplifier. If you wanted to use a set of loudspeakers with a resultant nominal impedance, e.g. 2? for one channel, you could damage the amplifier. If you want to get more power from this amplifier, connect the 4? speakers, if you want to provide the amplifier with more comfortable working conditions (lower heat generation), connect the 8? speakers. The difference in volume will be very small as long as both types of speakers have the same efficiency.

ferdek3033 · Answer

the fact that at 4? it will have more power, I know. but what I mean is whether the column on which he writes that it has an impedance from 4? to 8? will work on my 4? or 8? amplifier because my taste will easily attract both these and those.

What is a "hint"? With what letter do we start the sentence? A colleague is on a professional forum.
3.1.13. It is forbidden to publish entries that violate the spelling rules of the Polish language, careless and incomprehensible.
[P.]

AnTech · Answer

And what column do you have such a description on? Paste the photo. Is there a switch there?
A typical column has one specific impedance rating. Maybe in your loudspeakers the manufacturer gave not so much the nominal impedance, but the range of the loudspeaker's input impedance in the bandwidth. Hence the conclusion that depending on the range of tones - low, medium, high - the amplifier will be loaded with an impedance of 4 to 8 ohms. It does not matter for the correct operation of the amplifier.
So there is no need to think about, just plug in and play.

Zygmunt_mt · Answer

Will be. And you certainly won't overload the amplifier. Although I do not know what this column is. Perhaps with some switchable speakers. To explain very simply to you, imagine something like this. You have three things: a jumper, a 4-turn coil, and an 8-turn coil. With the jumper, you will short-circuit the output and overload the amplifier, and as a consequence, the protection will activate. The 4-turn coil will not cause this short circuit due to its greater resistance. The 8-turn coil, having the highest resistance, will burden the amplifier the least. When designing the amplifier, the designer assumed the use of (as if) coils with the number of turns in the range of 4-8. So not less than 4th turns. Is it clear now?

ferdek3033 · Answer

Zygmunt_mt I understand less. Just for your information, the amp is DIY made by a buddy.

AnTech, I am talking about the loudspeakers that are on the Allegro because I plan to buy some stronger ones, because the old ones are a bit weak for this AMPLIFIER and I want them to be in 4 ?, I will squeeze more from the amplifier

Luke15 · Answer

The column cannot have two impedances

.

Unless he has some kind of switch to change it.

Each loudspeaker has a given impedance which is equal to the resultant of impedance resulting from the speaker configuration - usually dependent on the woofers. The column cannot have 4 and 8R at the same time.

The impedance only changes as a function of frequency, but this does not matter in the amplifier.

AnTech · Answer

There are over 7,000 offers on the Allegro website. At the same time, dilettante bidders often write such foolishness that a person laughs.
Maybe the ones you write about come in two versions, i.e. 4? Or 8? Ask the seller a specific question. Besides, you can provide a description of these columns without providing a link to the auction. Otherwise, the topic will still be treated generally rather than in detail.

ferdek3033 · Answer

on the plate it just says 4 to 8 ?
and this is a fragment of the description of one of the auctions

"Audiophile loudspeakers T + A SK 80, music power 80 Watts. Rated power 60 Watts. Impedance from 4 to 8 Ohm. Range from 30 to 22000Hz. Bass diameter 20cm, Dome tweeter diameter 54 cm, tweeter diameter 3 cm. Bass Reflex enclosure Dimensions: H 43, W 25, D 20.
I highly recommend the best value for money.
Branded speakers sound beautiful, not Chinese made of rice. "

AnTech · Answer

The description and appearance (photo from the old auction) show that they have nothing to do with real audiophile speakers.
Out of curiosity, I put the name on google and found nothing interesting about these columns. The mystery of "4-8?" remains unsolved

Pablo1964 · Answer

I met with such a marking on the columns. As a rule, cheap home theater speakers are marked in this way. For the sake of safety, assume that they have 4 ?, although I would not be sure of that either. Most sensible advice - stay away. I have not seen GOOD columns with such an inscription yet.

Anonymous · Answer

It is possible - I have had the opportunity to see even weirder markings: Years ago, several dozen VIDEOTON loudspeakers passed through my hands. Several of them were labeled (original stickers!) 4 ?, a dozen 8 ? and a dozen or so 4-8 ? ... What's more interesting, some of them (regardless of the resistance written) were described as 60 W, and some as 90 W ... They played - without any particular revelation. Despite the 4-way design (!) And quite technologically advanced loudspeakers (Altus Times displayed in queues with social lists, etc.). Despite the fact that they cooperated with quite good amplifiers (PA 2801) and with relatively low power (background music in the bars), nothing great ... Of course, all the components that made up these loudspeakers were identical - speakers, crossovers, etc. So maybe the easiest way is to take a meter and measure the resistance of these unfortunate speakers? In the described case, I forged a theory that the reason for the description of 4-8 ? (and also the explanation of the total freedom in other markings) was the construction itself - 4 way ...

Zygmunt_mt · Answer

Ohoho ............. And the mid-tweeter is from this loudspeaker? Because it comes out to me that her (i.e. column) comes out sideways, from 11 to 29 centimeters, unless I need to go back to kindergarten? When it comes to the amplifier (as you write self-made), there is often nothing to be ashamed of. The electrode guys, or the triodes, make the brain stop. How much do you want to know what power it can achieve, give it some technical data, and we will quickly estimate how much it can have.

przemoleks · Answer

Is this connection of these speakers correct? notice that the speakers have 4-8 ohms and the amplifier has 6-16 ohms? can it play like that

Regulations p. 3.1.13. With what letter do we start the sentence? Please correct the messy spelling! [P.]

Luke15 · Answer

Columns must be either 4 or 8R - take the meter and measure.

If they have 8R you can play it safe, if 4R is already below the permissible impedance and such connection is not recommended. It may damage the amplifier.

Pablo1964 · Answer

The impedance of the loudspeakers is not a constant quantity - it depends on the frequency.

Luke15 · Answer

Nominal impedance also varies and depends on frequency? After all, it is known what we are talking about, so why this entry?

Anonymous · Answer

This method of marking has already been mentioned several times (4-8). Simply put: The loudspeaker has variable resistance - whether due to natural phenomena occurring in the loudspeaker (frequency), or due to a poorly developed crossover.
Once upon a time I had a whole series (about 60) of VIDEOTON's (Hungarian loudspeakers - all the same, all with the same speakers and all with the same crossovers) at my workshop. On some of them there was a nameplate of 4 ohms, on others 8 ohms, on parts 60 W, and on others 90 W ... - and this could be the second reason for such columns as yours - someone simply described "as inspired" .

przemoleks · Answer

Gentlemen, I am dark in these matters, just tell me at what frequencies to measure these ohms with a meter so that it shows the correct reading (it is 2000k, 200k, 20k, 2000 and 200)

Luke15 · Answer

200 ;) PS Not at frequencies, but at measuring ranges

przemoleks · Answer

thank you very much Greetings

przemoleks · Answer

thus they write:

and what a man should know when he buys such speakers and does not have a meter with him

Added after 41 [minutes]:

I checked these loudspeakers in the 200 range, it shows 4.3 ohms, so in a word, a failure, I will buy another amplifier, and in 2 weeks a party; /.
If you can, help me just choose a good amplifier for these loudspeakers. it must have written 4 ohms anyway?

Added after 7 [minutes]:

There are 8 ohm amplifiers everywhere; / I don't know what to do? can 8 ohms be?

Added after 6 [minutes]:

Give some examples of suitable amplifiers for this

Added after 8 [minutes]:

I don't want to be obtrusive, but if the speakers are 4-8ohm and 4ohm, they can't play on an 8ohm amplifier?

Added after 8 [minutes]:

or on which it says 4-16 ohm?

Zygmunt_mt · Answer

Seems to be getting a little hysterical. Concluding. Your loudspeakers have a minimum impedance of 4 ohms, and your amplifier is 6 ohms. If you absolutely want to apply them to this amplifier JUST, you will apply them and nothing so terrible should happen. Just don't set the volume to a maximum of, say, 60%. Check that it has the correct safeguards on the secondary side. So not protection from the network side. If it is an amplifier that is relatively well made and not trimmed, then first the protection in the power supply will instruct. And at one party, the controlled one shouldn't burn up like that right away. This is a bit of hysteria and data fetishism. It is supposedly a DIY. So it is also uncertain whether his data is correct. The 6 ohm impedance in the amplifier is a bit strange, rather rare.

Anonymous · Answer

The answers to the questions asked are already available - if not on this particular topic, then in at least a few others, already existing on the Forum.
In conjunction with :
3.1.16. Publish entries containing a question / problem report that has already been answered correctly. Before publishing an entry, the User is obliged to check, using the Forum search engine, whether the problem has already been discussed.
3.1.17. It is forbidden to publish entries lowering the general level of discussion, resulting from laziness or containing the demanding nature of statements.
I close the topic.

Understanding 4-8 Ohm Speakers: Impedance, Amplifier Compatibility, and Selection Guide

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