What is Speaker Impedance? | Impedance ohms rating explained

[@GabrielLeitePinto]

Very clarifying information, explained brilliantly, in my opinion. Every bit of information in its place. I finally understand the basic concept of impedance with this guy.

[@AxiomHomeTheaters]

Thank you for your kind words!

[@HughCStevenson1]

Good video, Andrew! I am a power electronics design engineer and I have a couple of points to add. An amplifier optimized for 8 Ohm is not worse than an amplifier optimized for 4 Ohms - it is just another design parameter. Similarly for speakers - the speaker designer can choose how many turns of what gauge of wire are used for the drivers and that ultimately determines the speaker nominal impedance. There is no better or worse. The power supply voltage for the amplifier is a key determining factor in optimizing the design for a particular speaker impedance. If it has to be capable of high power at 8 Ohm as well as driving 4 Ohm up to clipping then a penalty is paid in efficiency - more heat will be produced and bigger heatsinks and power devices will be required. It is a compromise... 4 Ohm speakers used to represent a benefit for Auto amps where only +/-12 V (in bridge) was available but with DC-DC converters now that benefit has gone. I don't know why speaker manufacturers still make 4 Ohm drivers - they just need fatter speaker wire for long runs! As you say - go with the manufacturer's guidance to avoid letting the magic smoke escaping! (Electronics runs on magic smoke - when it escapes it stops working!)

[@LC-ur8gv]

In 3 years of university they couldn't explain it so clear. KZbin should start handing out BAs. Thanks!

[@AxiomHomeTheaters]

Cheers, thank you for such a great comment, glad the video helped!

[@gamewarmaster]

Basically, when you half the impedance, you double the power by doubling the current draw from the amp. Some amps can take the higher current draw, others can’t or will overheat over time. Great video!

[@kevinedwards7206]

not only over heats.. but the power transisters can clip ( distort)..sooner?

[@matthewpeterson3329]

I got a very nice set of 4 ohm speakers from. Friend, and my Marantz receiver wouldnt drive them, or actually, they just sounded bad. This sent me down the impedance rabbit hole. This video was what i needed to finally understand the details. It will better help me match equipment, rather than just taking peoples word for it. Those salesmen dont always know whats best... they just want to sell stuff. Thanks for a great video!

[@agit-prop8193]

FANTASTIC. This guy would make a great science teacher.

[@searayser]

So Good... I am grateful to finally admit (As a 30 yr Sound Editor Pro) that I did not understand the "Speaker Impedance" story... now clearly explained, and appreciated - Thank You !

[@keithryan6368]

Thanks you for that brilliant explanation. Your simple, basic approach has enabled me to understand impedance and speakers for the first time in my 74 years - and it only took you 20 minutes! I wish I had heard this when I was younger and really into my musical equipment. Well done.

[@AxiomHomeTheaters]

You’re most welcome! I’m glad that I was able to help…it is such a difficult to grasp concept.

[@michael-4k4000]

E = MC2

[@democracybacksliding]

me also..!

[@michael-4k4000]

@@democracybacksliding LMAO all day long

[@MrFryfish]

He, in 20 minutes of explanation missed to say the most important idea. He, forgot completely where the coil of wire sits! The coil of wire is in a PERMANENT MAGNETIC FIELD. And that effects everything he said! It affects because a wire (coil of it) in a magnetic field BEHAVE completely different than a coil of wire in a free air! Did he consider BACK EMF. EMF stands for electro-magnetic-force. Which is happening in a speaker as the coil starts moving in that magnetic field... Well the things ARE more complicated than from a perspective of an audiophile... with an YT channel..

[@ruimartinho5943]

Finally, after been reading and watching videos from so many different sources, this one was the only that I needed for fully understanding the concept of Speaker Impendence! Thank you so much Andrew!

[@vettemaniac2237]

Clearly conveyed and great information to have ... It's a sorry day when you don't learn something new.

[@rs8197-dms]

Your explanation is good. All the important aspects covered well. I used to design power amplifiers for a living. As an amplifier designer, you are (almost) only really concerned with the impedance of the speaker at low frequency, as that is typically the region where the majority of the power of the signal lies. The lower the impedance of the speaker at low frequency (say 20Hz to 80Hz) the more heat will be generated in the output devices. Too much heat, amplifier fails. Reason - lower impedance results in more current, and heat generated is proportional to the square of the current. I used to specialize in designing amplifiers capable of driving a 2 ohm load at high amplitude without failing.

[@jm-vq4cm]

Hi, what specllialty do these 2 ohm amplifiers have that the 8 ohms amplifiers don't?

[@rs8197-dms]

@@jm-vq4cm The answer to your question would take several pages of technical explanation. In short, if you try to drive a 2 ohm speaker with amplifier designed for an 8 ohm load, the amplifier will fail quite quickly unless you keep the amplitude very low.

[@konglyyi2681]

I didn’t understand the word impedance properly for a long long time until I watched his video thank you sir

[@tbluge]

took me 7 videos to finally find this. I'm suprised there's not more views or likes. Thanks!

[@MrFryfish]

Yeah, because he missed other considerations...

[@martindekker8203]

So glad I purchased an amp that has a rating of 4 ohms to 16 ohms and will have no problems with any speaker impedance.

[@YusufGinnah]

As an ex-electronics professional, it *HAS* to be said that this guy, in this video, explained this in a far simpler way to comprehend than I could muster, to a regular Joe. Cheers for the upload. 😎🇿🇦🤲🏼🍉👍🏼

[@TheHififink]

Good reminder on the AC -vs- DC measurements. As you stated higher current draw at lower impedance can be a problem on lower end amps. The real issue is when folks at add a second set of 4 ohm speakers in Parallel without a speaker impedance box presenting a 2 ohm load to the amp.

[@9hundred67]

Excellent information. I have a 6 ohm amp from Marantz that should be better than my 8 ohm Cambridge Audio amp for driving 8 and 6 ohm speakers in a 5 speaker setup. I want more bass and depth from my speakers, without a sub.

[@samgamgee42]

.... love it when the light bulb lights up over my head..... great video

[@BitwiseMobile]

Speakers have reactive components, therefore you have reactance. The speaker itself looks like a coil to the the circuit, and in coils current follows voltage and that phase difference causes a resistance since I=V/R. That's reactive resistance. Impedance is just the sum of pure resistance and reactive resistance. For capacitance it's the opposite - voltage follows current - but the same phase difference occurs and you still get reactive resistance. Reactive resistance is emergent from the fact that you have a phase difference due to the reactance of the circuit.

[@lawrencejohnston5135]

Very well explained. This is a somewhat confusing topic. The counter-intuitive thought is that less ohms should make a speaker louder. This begs the question: why do speaker manufacturers not standardize the nominal resistance to eight ohms?

[@MrFryfish]

WHY SHOULD THEY!? A coil of wire of a certain thickess (different impedance) in a magnetic field behaves differently, technically and sonically that a thicker wire... And as sonically the mebrane REACTS differently in terms of air moved and conter-react to it, different NOTION we get. You see, things that are happening behind the scene, in electronics are connected and CAN a will influience the experience.. BUT npt in the way the massive clueless (unfortunately, because you need seriois study at Uni to understand..) audiophiles "experts"... their tags and glory vanishes in the front.of reality.. Do not hate me, because you might hate the truth and reality..

[@garyrowe58]

Glad I got over your initial comment about impedance breaking a 'receiver', and listened on.

[@blownouttransmission5832]

Thanks for the video , good to watch a clear explination. There are amps which are a great current source , others are great voltage source , tube amps for instance tend to be great voltage source amps but also have specific output taps on the matching transformers so suit benign impedance speakers rather that highly reactive ones , good current source amps like old quad 405/ii are quite happy with lower impedance and highly reactive loads . Where possible , try and find the impedance curve for your speaker or potential purchases , many 8 ohm speakers can have a rather whippy curve that reaches down to 2 ohms and above 10 ohms . My old Art stiletto 6 are rather benign staying above 6 and below 10 , they can sit at max volume with 100w amp all day and the sound is clean because the amp doesn't clip , (clip = distortion and damage) . Take your time and learn these basics , it will lead to better enjoyment of this lovely hobby . 😘

[@johnh3476]

You should be an educator. Thank you for taking the time to do these videos, I'm learning a lot and making my way through all of them.

[@AxiomHomeTheaters]

Thank you, I appreciate it!

[@MrBlacksight]

@john H, he is an educator already. And he get a far bigger crowd here on KZbin then he ever could In a classroom.

[@williamsmith9194]

I'm pleased that you addressed the issue of speaker impedance. I've heard this about half my life but never understood it. I know this is explained in books on the subject, but which one. Thanks for covering the issue.

[@whydotheathensrage]

Thanks, 👍ill have to re-watch after my hangover is healed... 🥴

[@timothyweers8054]

When I was younger, we had the opposite issue where an older stereo receiver was rated for a 4ohm speaker and all home stereo speakers were 8ohm. I was told that to make up for the difference was to connect 2 8ohm speaker sets together reducing the ohm from 8 to 4ohm per channel in order to avoid damage. Sometimes you could get away with using an 8ohm speaker on a 4ohm rated amp, eventually could blow out speaker if used independently. If this makes sense, it took me a little bit to grasp the concept. Realistically not sure how true the set up is or was in my case.

[@wphanoo]

I think it's totally safe to put 8ohm speakers to a 4 ohm amp, you can't do any damage. You will simply have a lower max output volume

[@ddognine]

Another way to think about it instead of nominal voltage is the nominal current draw which is the square root of the amplifier power wattage divided by nominal or rated impedance. And if you think about circuit breakers, they are rated by amperage, not watts or voltage, because wires and other components will melt at sufficiently high current given a sufficient amount of time. For example, if you have a 150W amp powering an 8 ohm speaker then it draws a nominal 4.3A of current. However, if you were to plug a 4 ohm speaker into the same amp, then the current draw jumps to just over 6A. The circuitry in your receiver/amp/speakers may not be rated for that much current causing it to overheat and shorting components especially if you like to really crank it up. That's why most subs are powered. That way the speaker and amplifier can be matched to avoid over-amperage since many subs are really low impedance, e.g. 2 ohms, and take a big amp to drive at sufficiently low currents.

[@abhijeetsingh-hb4ow]

That helps a lot. I got these old celestion creembacks 12 inch 8 ohms in parallel that I put together with a vox tube amp with a 4/8 ohm that I've been scared to test coz of mismatch. I'm a little surer now.

[@mikesteffes9999]

I haven’t watched the video - yet - but I’ve been a practicing EE for over a half-century. Perhaps what I’m about to say was covered in the video; if so, then I’m merely Capt Obvious; if not, consider this additional background info… The mathematical expression is: Z = R + jX where Z is the complex impedance; R is the DC resistance of the coil, i.e., a positive, REAL value. R is a function of the resistance-per-unit-length of the coil wire x the total length of the wire used to wind the coil. The term jX is the ac component, and can be positive or negative depending on the frequency being applied to the coil/magnet assembly. ‘j’ accounts for the phase of the ac component of Z, and can therefore be either positive or negative; X is the frequency-dependent magnitude of the ac component of Z. These characteristics are what give a speaker an impedance that is different at every frequency in the audio spectrum. And why 1kHz is the accepted frequency at which to specify Z.

[@paulmoadibe9321]

you made this video 2 years ago and I just saw it today..... WHY ??? that's very good info and well explained ! thanks so much 👍👍

[@paparoysworkshop]

Very good explanation on this topic. I've had people tell me that they have connected 4 ohm speakers to an 8 ohm amp many times and never had a problem. I've always replied that as long as you keep the volume low, there should be no problem but once you crank up the volume, you are taking a risk to break something. And of course, if this did happen, they will blame it on something else. Hey, it's your amp and your money... do what you want. Ever notice that when someone asks you for advice, but the advice is not what they wanted to hear, they get upset?

[@mrsaasmrsaas2742]

3 years of learning (normally) will take about 3 months, when you are the teacher! I mean, When you understand the basics of something, it is easier to learn more about it. Thanks my friend greetz Wouter from amsterdam keep it up!

[@AxiomHomeTheaters]

Thank you so much for such a positive comment! I do my best to explain techy things in easy-to-understand language.

[@philmorin4966]

Thank you, Professor Andrew, for the fundamental explanation about Impedance. I've always attempted to simplify the explanation with the word "MATCHING" to my non-electrical associates, although high Z and low Z require a more intermediate explanation.

[@ovalwingnut]

"The Speaker Whisperer".. I'm in geek heaven! Thanks so much.

[@victoryvisiontour]

Thanks for such a great explanation of resistance vs impedance.

[@hidewong]

Hi there , thx for ur knowledge of impedance sharing . From ur entire presentation , can we said the power amp which rated 8 ohm and 4 ohm is capable to drive 6 ohm of passive loudspeaker without any issue ? As the speaker impedance is higher than power amp ? Thx

[@duroxkilo]

excellent video. i believe the international standard refers to nominal speaker impedance as a somewhat minimal resistance value (80% of the stated impedance) presented to the amplifier. - a 8ohms speaker should not present a lower than 6.4ohms resistance to the amp (8 x 80%). - a lot of receivers have terms like 'dynamic power output' in the 'thick' manuals, specifications section. a receiver amp w/ 100W per channel at 8 ohms, will deliver up to 170W into 4ohms but for short duration and at higher than normal total harmonic distortion. yamaha, onkyo, denon, pioneer, etc, all have the capability to drive v low impedance load bursts (2-3 ohms).

[@AxiomHomeTheaters]

Thank you, and thank you for covering accurate information that I did not include in my discussion of impedance!

[@Macheako]

Literally just a guy standing in front of a camera explaining how a somewhat complex system works....and yet, you’ve helped me more than those videos sporting nice and shiny graphical design teams 😂✌️ Appreciate the break down!

[@AxiomHomeTheaters]

Hey Matthew, thanks for that!

[@Macheako]

@@AxiomHomeTheaters Thank YOU!

[@kevinfreestone9822]

Thank you very much. Most enlightening. I studied both physics and electronics when I was in, what you.might call, hight school, but that was 36 years ago. A great refresher. Thanks again.

[@thomasbolton8373]

excellent work , great clarification, you obviously have a great understanding of your topic, thanks

[@MrCobbleg]

Very concise information. Good job.

[@Pootycat8359]

Oops! "Reactance" (X) is produced by either inductance or capacitance (no resistance). "Impedance" (Z) is the combination of reactance & resistance. It can be purely resistive (R + j0), inductive (R + jX) or capacitive (R -- jX). .

[@stephenmead5488]

Thought I would scan the comments to see if this clarification/correction was addressed before I chimed in. You pretty much covered it. Now let’s sit back and wait to see how many audiophiles ruminate over the mysterious “j” you tossed in there.

[@Pootycat8359]

@@stephenmead5488 And if they don't know what i am saying, may a flock of blue-j's shit on their heads. And they should be aware that I am very fastidious about correct grammar and spelling.

[@Pootycat8359]

Oh, yes, they must also realize that we electronics technicians & engineers live in an imaginary World!

[@spm0]

@@stephenmead5488I am an Audiophile.I didn't Pay attentions to Complex numbers and Vector Algebra,Not even in Differentiation or Intigration when I was in 12th standard😛,the time I were being forcefully tought all those .I asked my match tutor what's the point of learning it,What is the use of it in Real world.Sadly,maybe because he had not been in an applied field so He couldnt answer me and make me interested in the subject.I wish he could.😔 Funny fact Wrong career choice made me an Automobile Engineering student😂.But as I started understanding the use of Each kind of Mathamatical Operations to analyse and design everything I use In daily life, I got interested and learned it Myself digging my old high school books😂.I had to study double time😝😂. And later my Audiophile nature forced me to Learn about Complex Numbers😂 for A.C. Filter Network Analysis & Designing. This Mister 'j' is the same Operator that 'i' used to hate in High school.😂

[@stephenmead5488]

@@Pootycat8359 I prefer to think of it as “complex”😬

[@carolchandler1753]

Well done. Thank you. I always wondered what the nominal impedance meant. Great job.

[@cowboybob7093]

Even though I do not question the bottom line and the equations, I'm still need to work on my preconceived notion about this topic, which I would rather not repeat since I know it's wrong. Thanks for the rule-of-thumb and how it's derived.

[@LeafyGooner]

This was very helpful. My worry is an 8 ohm speaker that has a drop to 3.9 on the published impedance curve. Hopefully this wouldn’t be enough to put my vintage receiver (the manual states 4 -16 ohm speakers ok) into protection.

[@renegadeflyer2]

I was told I could run 8ohm speaker with a 4ohm amp. I have done it. Because I was cheap and I had the amp. And yes the amp seemed to be happy. But the speaker was not performing to its full potential. I have since bought a 8ohm amp and the speaker sounds so much better. The speakers sound range improved so much especially the bass. Excellent video. 👍

[@arvidlystnur4827]

A good rule of thumb in musical amplifiers is one may add a higher ohm speaker to a lower ohm rated amp but not the reverse. For example I have a cheap 50 watt pa amp rated at 50 watts 8 ohms, but will except a 4 ohm load, which will increase the amp output to about 80 watts. This amp is mono. I took one 8 ohm pa speaker to a large room lecture and the amp struggled to put out a clean signal. I hooked up a second 8ohm speaker in parallel which dropped the load from 8 to 4 ohms for the amp which played much cleaner. If this amp couldn't handle a 4 ohm load and I needed to use both speakers in different places in the room, I could protect the amp by connecting the 8 ohm speakers in series rather than parallel, producing a 16 ohm load, which unfortunately drops the amp 50 to about thirty watts thus decreasing the amps output.

[@mikesteffes9999]

@@arvidlystnur4827 you just described what a lot of harp (harmonica) players try to achieve deliberately: amp/speaker mismatch. Tube amps typically tolerate a 2::1 mismatch by design, in either direction. Yes, the output sonic characteristics are different whether it’s 2::1 or 1::2.

[@dannypiercesr]

Thanks for sharing, great information, well explained

[@TheXmannot]

Spectacular explanation! I don’t understand it all (I’m not an engineer lol), but that’s the best explanation I’ve ever heard!

[@AxiomHomeTheaters]

It's a tough subject, glad the video helped you understand it better, thanks for the comment.

[@kaindog100]

Great explanation. I have an 8 ohm output on my guitar amplifier but I have a 16 ohm speaker I use. Is it just simply the volume is lower than an 8 ohm speaker? From what I’ve read it is safe to use the 16 ohm. Glad I came across your channel.

[@arvidlystnur4827]

Yes, if you hook a matching 16 ohm cabinet in parallel your load will be 8 ohms, won't damage your amp but be louder.

[@stighenningjohansen]

Speaker impedance also include the fact that a speaker voice coil is a dynamo, that feed current back into the amp, wich is a short circuit, as long as it can keep the output close to the signal, complicated interactions going on

[@enigmaticloremaster1700]

Hi great informative video . Was wondering if you can you use 2 x 4ohm speakers hooked up in series? could that be run as an 8 ohm load safely? Or running 2 x 8 Ohm speakers in series creating a 16 ohm load to be run on a 8 ohm recommended output?

[@saloncaruso3701]

Explained very well, thank you very helpful

[@Mrsteve4761]

Absolutely superb explanation, thank you

[@DiGiTaLdAzEDM]

I have a Yamaha AX-930 integrated amplifier. It is rated down to 6 ohms. RMS power 130W per channel/Dynamic power 300W @ 4 ohms. I plan to hook up 2 Cerwin Vega RE30 4 ohm speakers (RMS 250W), as this is the equipment I have. Can I offset any issues the amp might have by running a couple of computer fans set in exhaust mode on top of the amp grill above the heat sink. This would remove much heat and thus avoid overheating. As long as the amp components stay cool, does this offset any problems caused by the amp having to provide additional current? Also, I am buying new cables (GearIt). Does wire gauge have any bearing on any of this? I have ordered 14 gauge pure copper wire-2 runs of 15 feet. Thanks for any help.

[@MatrixRoland]

Back in the 80’s, a fellow classmate in my electronics class wired some car speakers in parallel which basically cut the impedance in half. He literally blew a hole in one of his car receiver power transistors.

[@johncoscia5258]

Is a window box fan laying on top of my Denon AVR2000 a good idea ? Every time I check the amp it's cooler with a 12in sub and two 3 way 8 ohm 150 w fronts all in parallel ? DC resistance reads 8 ohms , is that a value that can be a guide for any speaker before oscillating things ? Using RCA connectors for pre amp function doesn't sound as good as just speaker wire in parallel , am i doing something wrong ? Thanks .

[@pcgold944]

I appreciate the comments that it was well stated should have added at the end if you reverse everything the reverse makes it basically doubling the ohms is not a problem if you take a 4 ohm load on an amplifier with 2 sets of 8 ohm speakers and the amp is rated 250 watts etc All should be well you know what I'm saying

[@mountainmaanush3909]

Very enlightening information indeed. Thanks.

[@soaringvulture]

Finally. I have studied some electrical engineering and know about inductive and capacitive reactance. So I was always confused by specs like "8 ohm impedance" for speakers. Because I knew impedance was a function of frequency so how can you just give a single number? But it's some massive kludge. The speaker's impedance varies over its operating range and they just pick an average. Ecch.

[@mikesteffes9999]

I think you’ll find the speaker manufacturers adopted a standard of 1 kilohertz as the measurement frequency for specifying loudspeaker impedance. Why a single number? Because it’s easier to specify at a single point in the audio spectrum; however if you want a frequency response CURVE over the entire audio spectrum, some companies will provide them.

[@steveareeno65]

This was really good. although I still don't fully understand it, I have a way better understanding than I did before. I'm in that predicament. I have acoustic research speakers that were given to me. I cannot find any documentation on them anywhere because they've been out of business for a while. I took the speakers out of The casing and they are marked 4 ohm. Each speaker has a woofer, mid range, and tweeter. Only the woofer and mid range are marked with ohms. Not sure about the tweeter. I'm trying to find a receiver to match the speakers.

[@robertchauval]

Whats the model no of your AR speakers? Im a big fan of AR loudspeakers, I have restored and modded my own M4, and M6 and I have friends AR48b and M5 to restore and repair atm

[@6643bear]

Hi great informative video, make things understandable. Regards mark

[@LifelongMusicJunkie]

I bought a set of 4-ohm speakers that are driven by an amplifier (Rega Brio) that has two settings, 50 Watts RMS into 8-ohm and 73 Watts into 4-ohm. Rega does say that extended high volume play will cause the unit to get a bit hot in the 4-ohm speaker setup. I have no problems so far. Thanks for the explanation. Have you discussed which gauge wire to use for 4-ohm speakers? I will take a look at your video collection. Thanks

[@AxiomHomeTheaters]

As long as the amp does not get too hot or shut down you’ll be fine. I answered your wire question in another comment. 😊

[@KetogenicGuitars]

if you have 2 pieces of 4 ohm speakers per amp you can connect them in series instead of parallel. That makes sure the power source and fuse will not blow unnecessarily. Fuses in power source are your best friends. It is possible to use underrated fuse like 2.5A in power source to make sure speaker driver - like an expensive low powered tweeter- will never get blown. The power source and amplifier can be treated as separate devices. Ebay and for example Soundimports have separate power sources and amplifiers available at very reasonable price.

[@gtr1952]

I was interested for my guitar amp/speaker application. I have outputs for 4, 8 and 16 ohm. I have cabs that have 1, 2 and 4 speakers. I try to keep everything at 8 ohm. So if I use 2 speakers, to keep the cab at 8 ohm, do I use 16 or 4 ohm speakers wired in series? Electronics are not my bag, sometimes I don't understand. 8( --gary

[@vincentmontambault217]

But apart from the concept and the risks with using different impedances on an amp, what is the advantages of using a 4 or a 8 ohm on an amp that's designed for it? Is there a different sound quality on one or the other? What we should aim for, lower impedance or higher impedance?

[@Graham_Wideman]

In many power-delivery scenarios, for a particular power it's more economical to use higher voltage and lower current, as the lower current produces lower heat loss attributable to the resistance of the wire, or you can get away with a smaller diameter wire for the same heat loss. This is why utility companies transport power over long distances at very high voltage. So you would think using an 8 ohm speaker would be better, using the amplifier with higher voltage and lower current output. However, many audio amplifiers are limited by their maximum voltage output, yet can supply enough current for loads of 8 ohms, 4 ohms or even 2 ohms. So in that case, changing from an 8 ohm to a 4 ohm speaker allows the same maximum voltage but twice the current, so twice the power delivered to the speaker, though also with twice the heat loss in the wires, unless you also increase the wire size. The video covers this are 12:00.

[@vincentmontambault217]

@@Graham_Wideman yes that I understand, but what is the sound quality difference between lower and higher impedance? Is there more distortion with one or the other?

[@stephenc2738]

Very well done. There is a host of high end amplifier and speaker systems with nebulous recommendations in matching to some speakers which have wildly fluctuating impedance loading. Some exotic tube amplifiers will behave very differently and sound awful. I owned a solid state amplifier rated 50 watts RMS @8 ohms, 100 @4 ohms and 180 watts @2ohm loads. It delivered superior sonic performance than another amplifier I owned which was rated at 100 watts @8 ohms.

[@AxiomHomeTheaters]

Exactly…power is not the only thing that matters, so it’s never a good idea to blindly follow specifications!

[@zee7333]

Thank you! Impedance finally makes sense.

[@AxiomHomeTheaters]

Glad the video helped, thank you for taking the time to comment!

[@geniferteal4178]

So is more or less impedance better? If you're putting together a system, is a 4 ohm speaker with an amp that can perform at 4 Ohms going to have any advantages over an 8 ohm speaker with an amp that only handles 8 ohms? We see the 4 ohm rating typically is twice the wattage. Is this just math? The short answer is yes but how does it relate to hearing louder sound or not?

[@christopherl.roberts539]

Quick question... Would all of what you taught within this video remain absolutely the same if one thing was different ? If your information was based off of nothing but home audio would it be the same say if I interchanged home audio and car audio ? Say that i'm not happy with the performance my subwoofer is giving me on a 2.1 computer setup and The little sub infact works well for what it is but you cannnot go past 1/4 on the dedicated bass knob because your trained ear can hear distortion etc. And with the bass knob at no more than 1/4 and your volume not being able to be turned up past the halfway point either leaves me without quite a bit left to be desired in a sub that can give real excursion and some of those lows without bottoming out all while being able to access the power and dedicated bass knob and give that upgraded woofer what I couldn't give it's runt of a brother . There's seems to be many versions to the system I have although pretty much all looking almost identical to all the ones that came before it . All I know is that I have a beefy 6.5 inch car sub getting here on Friday and I would love to just remove runt and replace with beefy boy . Where do I start? Do I try to look for the amp ohm load and if so where ?

[@democracybacksliding]

Absolutely perfect teaching...Thank you...!

[@AxiomHomeTheaters]

You're welcome, and thank you for taking the time to comment and compliment!

[@pcgold944]

Very well put together but the one thing you should have added at the end is if you do the reverse where the reverse information is done then it is easily done where you take the numbers and work them backwards it does work where your bigger speaker your lower bigger power output into the smaller speaker doesn't have any problem with the amplifier something like that anyway trying to figure out what I'm typing this in you know what I'm trying to say anyway

[@arsenalmanc1011]

Thank you so much. I still don’t understand all the maths but i understand why does impedance matter now. Appreciate that.

[@AxiomHomeTheaters]

That’s great! Thanks for watching.

[@herrkiwi3110]

This was really helpful, thank you.

[@FOH3663]

What happened to using Nyquist complex impedance graphing? 20 to 10k, inductive, capacitive. It can be a powerful tool for explanations like this.

[@sohanpal8152]

well explained sir.

[@tomweis1194]

Thanks for taking the time to explain this topic! I’m not an electrician or engineer so this is helpful. I do wonder though, how speaker engineers make the decision to design a speaker with a given impedance. I mean, wouldn’t it just be easier if everything was 8 ohms? Why 4 ohms at all?

[@FOH3663]

Countless reasons really ... loudspeaker design is an exercise in comprimises. There is no ideal path to take, ... as every step is a compromise one way or another. You're juggling different drivers, each with differing characteristics. Besides, the loudspeaker impedance isn't just one value (something the presenter didn't fully cover). Impedance changes per frequency ... oftentimes those variations can be huge.

[@_Nordfors]

Super cool video. I’m sorry you feel the need to apologize about math. Thanks.

[@lastmanstanding9389]

To put it simply, just remember that manufacturers always go the cheapest route and with amplifiers they will put in the minimum size transformer or the minimum number of transistor/mosfets pairs in the output stage. So when you connect the 4 ohm speaker to an 8 ohm amp, then the transformer could overheat and burn out because it now has to supply double the amperage or the output trannies could blow. Subwoofers are the worst as the impedance could go lower than 4 ohms and is why they should have an infrasonic filter in the signal path.

[@vettemaniac2237]

I guess you're not familiar with McIntosh ... Cheapest route? I think not.

[@joeldobbs7396]

Thank you very much, the other videos I tried didn't give any of the science behind the numbers and left me with some do's and don'ts but no real understanding. Of course if I blow something up now I have no excuse, but all knowledge has a price...

[@AxiomHomeTheaters]

You’re most welcome! I’m glad that my explanation made it easier for you to understand.

[@osirismarbles5177]

Just seeing this. Probably the best most clear explanation of impedance I've ever come across. Brilliant.

[@dpdp006]

Wow Thanks for detailed explanation . One q my Pioneer C21 6ohm speaker 🔈 i really need to crank it up my Yamaha TSR7850 ( using zone2 + 5.1 both ) to hear good sound. Any idea why this is the case

[@AxiomHomeTheaters]

You’re welcome. I’m not sure why you would need to crank it…what level does the Yamaha display to get it to a satisfying level? Also check your speaker setup to make sure everything is correct.

[@gdm_audiophile]

Such a great explanation. Thanks so much for taking the time to explain this topic so clearly. Awesome!

[@rtozzz]

Hello I have an amplifier rated for 8 ohms impedance speakers, I have conected a 4 Ohms speakers in serial with a 4 Ohms power resistor in each channel, is it something wrong with it?

[@arnask7071]

Hello, what happens if I run 16ohm speakers on an 4-8ohm rated amplifier? Does it mean that the speakers will receive less power from the amp in comparison, or are there other acoustical issues? Thanks

[@danilolorenzetti712]

Thanks very much! Excellent explanation.

[@Patrick-ge2zn]

Learned a lot today , thanks a million . 👍

[@apexclaimadjusters5816]

curious how this plays into tube amps. rule was you can damage the amp if it's run without a speaker connected? Is this true and if so why?

[@robertchauval]

tube amps are almost always transformer output and to keep things simple, basically large inductors (transformer) open circuit without a load (a speaker) can create large over voltages that can short out the internal windings of the transformer.

[@davidjudd951]

When I went to rebuild a pair of older 3 way speakers, I was surprised to find that none of the old drivers had matching ohm ratings. One speaker the tweeter, was 8 ohms, another, the midrange, 6, and the third, the bass, was was 7 ohms. I replaced them all with 8 ohm drivers.

[@bradkaral1188]

Excellent video. Simple, clear explanation, in a step-by-step fashion. I will now use this as my go to video for explaining speaker impedance to others.

[@AxiomHomeTheaters]

That's one of the best compliments, sharing with others, cheers!

[@ptg01]

I've always wondered why 8 ohm is the most common nominal impedance rating and it ranges from 2 to 32 ohms nominal impedance.... Definitely understand impedance fluctuates depending on what is being played. Some speakers drop to less than one ohm !

[@kramm9322]

Well done sir, well done

[@roberteshaw4590]

Very impressed. Thank you very much. You brought a difficult (hard to understand for a lay person) topic out and explained it very well. I have an integrated amp by Peachtree that is nominally rated at 8 Ohms, however, will go as low as 2.5 ohms. That allowed me to add a pair of Focal Aria 948's that have the same ohm ratings, which required an amp to accommodate. Never fully understood until your video. Again, Thanks Robert TN

[@AxiomHomeTheaters]

You’re most welcome Robert! It’s amazing how these terms are thrown around and yet most people I speak to have no understanding of the concept. Hopefully this video was able to clear it up for others as well as yourself. Really appreciate you taking the time to comment, as well as for watching.

[@michael-4k4000]

The way my Uncle Ned explained it was a cow eat hay, then u milk 🥛 the cow and have milk, then you use the milk to make a cake 🎂, then u put icing 😉 on the cake 🎂 and then u eat the cake. Think of the candles 🕯 on the cake as Dolby Atmos

[@michael-4k4000]

@@AxiomHomeTheaters do u want to to have my Uncle Ned on the channel?

[@rulesflyer]

Many thanks for this "brillantissime"* explanation. *as we say in french :)

[@jko560]

Excellent primer!

[@US_Joe]

Well done - enjoyable episode - Thanx👍👍👍

[@moogoomoogoo5990]

Such a helpful explanation

[@robertchauval]

Understanding loudspeaker impedance is important without doubt but for me the most critical thing in the amplifier-speaker interface is the amplifiers current delivery spec regardless of whether the speaker is an easy 8 Ohm load or not..... From my experience high current delivery amplifiers (40A??) typically sound very good even with safe and easy 8 Ohm speakers. At the end of the day an audio amplifier is really a motor controller (the loudspeaker drivers ARE motors) and effective and stable motor control systems always have considerable unused headroom. Audio amplifiers are no different, current delivery headroom is a must for the amplifier to work well within its THD and IMD curves and too tame the speaker and remain in control of it. This is very different from the often quoted and misleading damping factor DF (low output impedance). Low output impedance of an amplifier is nothing, and absolutely useless without matching current delivery. They do not go hand in hand and you can hear absolutely the difference.. so always dig a bit deeper and try to find the amps output current capabilities its a good indicator that it can work well with most loudspeakers

[@oblio63]

I was hoping I would hear why there are 8ohm speakers for mainly home, and 4ohms mainly for vehicles. I always thought it was cause vehicle amps need to be smaller cause lack of room and the lower the ohms also the more distortion gets through. And since a vehicle environment is noisier than the home, 4ohms is the thing there, and 8ohms for the home has less distortion which works better for home. Am I on the right track?

[@adriangiles5086]

@oblio63: I think it's because traditionally the power supply (car battery) is 12V so Pmax=V²/R so 4Ω is preferred for max power. Power supplies for home systems don't have this issue and might be the mains voltage rectified with a toroidal transformer and caps down to 35V DC say and 8Ω speakers. That was the 30 yr old answer anyway, circuits have got a bit more sophisticated now.

[@DeVoNmotorsports]

typically a speaker with higher impedance or OHMs will have less bass and one with lower impedance, will have more lower bass response, the speaker driver doesn't care what amp its plugged into but the amp does the amp is the limiting factor if it can drive a 4 or 2 ohm or only 8 or 16 ohm if the receiver is not powerful enough you simply can not turn up the volume as much, amps put out a specific power depending on OHM of speaker,

[@realvanman1]

Just to nitpick a little: Reactance (be it Inductive or Capacitive) does not include resistance. Impedance is the sum (the vector sum to be precise) of the Resistance and Reactance of a device or circuit.