Understanding Speaker Impedance and Speaker Switches

This video explains how speaker impedance matters, especially when connecting multiple speakers to your HiFi amp. It also demonstrates how speaker selector switches protect your amp from low impedance.
For more details on this and more articles on connecting multiple speakers, please see my website: geoffthegreygeek.com/category/... Questions are generally answered from the webpage only.

[@Geoffthegreygeek]

I spend a great deal of time updating and answering questions from the webpage. If you have a specific question, please read the relevant article on the webpage and post your question there. Rarely do I get to answer questions posted here in KZbin, although others often help out. geoffthegreygeek.com/category/home-av/connecting-speakers/

[@Roadking26]

Geoff. Here is what I sent you in an email like you asked. Please let me. Know if you received it. Maybe someone else can chime in if they know. You would think as long as I have been playing I would have ran I to this, but this is a first. here it is. Hey Geoff. I have a Bugera Vintage V22 Infinium. It is a 22 watt combo amp. On the back is a jack for connecting an extension cab. Where the jacks are for the extension speaker, and the jack, and plug for the speaker in the amp it states "amplifier output 22watts 4 ohms minimum speaker impedance. Jacks Paralleled". (The speaker in the amp is 8 ohms) Next to the jacks is a switch that has a setting for 4, 8, and 16 ohms. The extension cab is an Egnater 1x12 and is 16 ohms. If I plug this in to the extension jack, what would I set the impedance switch to? I do not want to damage my amp. You are the first person I have come across online who seems to know what they are talking about. I hope you can help me with this dilemma, but I'm sure there are plenty of people on here that have an answer, but I would like to hear all opinions including the Grey haired geek. Thank you in advance,

[@kgriff5537]

Assuming, the connection was done correct. Does multiple speakers connected to one channel affect amps? In other words, do you get the same output from the amp per speakers as you would if you connect one speaker to one channel?

[@fusion_fever1592]

Hi sir, thanks very much for the vdo, this one vdo gave me a clear picture of impedance,Hi I have a small doubt. please give your expertise, what will be the formula for connecting two speaker's of different impedance(say 1 speaker with 8ohms and other with 4ohm) in parallel... i know the calculation for series (10+4=14 ohms),I am planning to build a diy soundbar with 2.0 amplifier board (stereo left n right channel), and I want to add 1 woofer to the amp,(thereby total 3 speaker for a two channel amp).

[@bryanvega2571]

How i can connect 8 speakers 8 ohm to 1 ohm amplifier (Taramp)

[@RoraighPrice]

page not found.

[@sashacolic2427]

If your speakers are rated at 8 ohms, that means impedance will vary from 16ohm and during heavy, complex bass and orchestral music, it will sure drop down to 3.2 ohms. While 4 ohm speakers will drop down to 1, 2 or zero ohms and drain the current from your amplifier severe. The more high current you provide, the more headroom you have, also with high current amplifier you prevent amp and speakers from potential damage - clipping! After trying 4, 6 and 8 ohm speakers, I realized minimum power amp is 100watts per channel into 8 ohms and close to 200watt into 4 ohm, to drive most speakers. As for 4 ohm speakers or connecting 2 pairs of speakers, they require at least 150watt/ch high current amplifier to drive them well. For a year I drove Dynaudio 4 ohm floorstander with 75w/ch high current amp and that power wasn't enough to take control of the bass and soundstage (stereo mode). It was a torture like driving heavy Land Rover with a 75 horse power engine. While minimum requirements for such a beast is 120hp. Hope this helps someone :)

[@bolt-action9470]

This is hands down the best video for information on impedance. I'm no expert, but thanks to this I was able to wire my subs down to a safe 2 Ohm load.

[@gp85hkg]

HURRAH...that was the best explanation I've seen so far...now I completely get it..!!! Thank you 😃👍

[@jakedillingham]

disastrous for the poor amp! That made me laugh! Thanks for such a great video, may it live long on KZbin.

[@santospoland]

Hi Geoff, just subscribed. Thank you for all your help! I can now connect 2 speakers to each amp, 4 in total to the stereo's two amps.

[@arielbelisario728]

Learning something new is a wonderful thing, thank you Geoff!

[@mgbob600x]

Basically, you never want your Ohm rating to be lower than what your amp lists, because less resistance means there is more current going through the amp, and the amp can literally be fried. Too high of an impedance, and your volume will be too low because there is too much resistance. This video is intended to make one understand what impedance you should be looking for when connecting speakers to an amp, but it doesn't explain the concept of impedance itself.

[@flowmaster2010]

Oh wow so I really did fry my amp! And I thought the higher the number the better! I was running 16 ohm to my monoblock 4-8ohm amp! Thanks now I know

[@Querencias7]

O U T S T A N D I N G ! Excellent info on speaker impedance without getting overly technical. Most obliged G3 sir. Really appreciate your altruistic labor here. All the best.

[@swinde]

An impedance assigned to loudspeakers is essentially a "nominal" impedance. Impedance varies with frequency so there is an "impedance curve" for every loudspeaker or speaker system. For instance my AR-3a speakers have a nominal impedance of 4 ohms, however this speaker's impedance varies from a low of 2.5 ohms at 900 Hz to 22 ohms at about 45 Hz with various settings of the speaker's mid-range and tweeter controls. The overall impedance at most frequencies is close to 4 ohms. This is something you should know, but in general this video gives excellent advice on how to hook up speakers, but there will be some speakers that deviate from this simple solution.

[@Zack-dk3pt]

yea that is the kind of information you would expect to hear given the title.

[@Jenuin]

Thank you. Currently getting to install a whole home audio setup

[@predaking2wings]

i want to do the same, but its a little bit confusing at first, trying to get the right gear!

[@Rendraco79]

this is excellent! very good video. every day i learn always something useful congratulations and thanks!

[@ajra-roxas4449]

Thanks for this video its very educational, like me who want to know more about speaker matching to amplifier. thanks alot make more videos!!!!

[@ShibuPaulAluckal]

Awesome video, impedance explained in the simplest way possible.

[@hbcbz]

Excellently done video the only thing I would add is does going on 4 ohms versus 8 ohms change the actual volume sound

[@SIBERIANDEATH]

Best speakers connection tutorial on youtube, congrats!

[@ephjaymusic]

Very clear and instructive!

[@harryfandakis2339]

Good and simple explanation - gongrats from an electrical Engineer !!!

[@behexen0190]

If you think this video did a good job explaining anything, you're no electrical engineer. You need to ask whatever school you went to for a refund.

[@bujoun76]

These loads turned out to be very much the opposite of what thought! This is awesome. Now I can build a bigger and better tower speaker!!!

[@pramodkadpate3904]

What I really learnt was how not to go wrong while matching the speakers with the amplifier. But what I wish to know is whether using multiple speakers in parallel or series make any difference in audio quality.

[@billyharding2874]

Jeff good lookin out and great source for a start to understanding wiring speakers correctly so I can tweak the system correct and most of not blowing amp..I will be in touch after I write down all my ohms on back of my gear

[@danielcampbell6564]

Thanks for all your great help Geoff! Jesus Bless Your Life my Friend.👋👋👍✌

[@i_smoke_ghosts]

im an arsehat coz im old now and sorta thought i knew wat i was doing and ive just learnt i know nothing and need a lot more learning - 'coz optimizing mean beats is funtimes. thanx for the upload.

[@mariakey3597]

Very clear explanations, thank you, ,,

[@somnathchatterjee1975]

Sir, thanks it's help me a lot more , waiting for your next tutorial about transformer series & paralal connection . ❤️ From INDIA 🙏

[@TBN74]

Very clear, now I understand! Thank you much!

[@Djdubbyrappy]

This shit helped me within the first 2 minutes. Thank you.

[@sisirroy998]

Impedance (Z) is known as equivalent resistance value of a circuit. A speaker coil has three parameters like coil resistance, coil inductance and coil capacitance, usually known as R, L, C. Impedance (Z) is calculated as R+kL+1/(kC) where K=2*Pie*F (F=frequency & Pie=3.14), R is the coil resistance in ohm, L is inductance value in milli-Henry and C is capacitance value in micro-farad. The unit of Z is ohm. Be remember, standard values of speakers are 4, 8 or 16 ohm. Here, Mr. Geoff clearly explained how we can obtain desired coil resistance with speaker having different coil resistance, like getting 4 ohm with 2 X 8 ohm speakers, or getting 4 ohm with 4 X 16 ohm speakers etc. to match desired value of output of amplifier.

[@Autigers2013]

Do you have a video I can watch? I would totally watch!

[@techmonster2632]

why its called impedance not normal resistance , why the change in names

[@BADNEMMUSIC]

​@techmonster2632 because its in AC current

[@daftstuff6406]

very helpful indeed! Thank you for your time and sharing this.

[@bash-shell]

This was amazing. Thank you.

[@THE-CROWZ06]

Awesome info thank you so much.

[@mixme8655]

thank you very well explained

[@eliasvankan9772]

I really like your explenation thanks

[@Giblet535]

I repair amplifiers. This video is great for my business! Thanks!

[@vsmichael1]

Giblet535 me too, letr blo

[@Chiroman527]

Geoff, THX for this very helpful Video. My question is : Does wiring 2 pairs of Bookshelf speakers in Series affect the sound quality ?

[@TimpBizkit]

You can use a double pole double throw switch to change between two speakers series and parallel. I used a quadruple pole double throw switch on 3 12 volt batteries to switch easily between 36 volts to run an SMSL SA98E amplifier I have and 12 volts for other devices and/or charging. I unfortunately can't show you how to wire it in a youtube comment though.

[@jameysummers1577]

Great video!

[@narf0339]

Still totally no idea what is impedance. Title of the video should be "impedance calculation", not understanding impedance.

[@Geoffthegreygeek]

Fair Comment Junn. I find most people don't want to know the technical details, just what to do about impedance, hence the lack of a technical description. That is why I provided links in the video to my various articles where there is a better explanation. perhaps start with geoffthegreygeek.com/understanding-speaker-impedance/.

[@denisroscic6267]

Geoff the Grey Geek

[@AudioReplica2023]

totally agree

[@zeeshanrahatsultan9757]

my brother impedance is just a fancy word for the electric resistance of your speaker coil

[@vintagestereobuff7005]

Impedance is defined as TOTAL opposition to current flow in an ac circuit. This total opposition consists not only of dc resistance, but inductive reactance(measured in ohms), and capacitive reactance(measured in ohms).

[@GamingVlogsWDeathLord]

This makes so much sense thank you so much

[@michael6692]

best vid yet on youtube i have a 600 watt amp (( 4 - 16 ohms )) need to run 4 mid speakers and one 750 watt sub can do it now no need to buy a over priced amp again ,,

[@alnordalexraymond1071]

thanks...im happy to know that...i thought that the amplifier only support the ohm that recommended..example 4-16ohm for both channel...this video show us that it divided for both channel 1 channel support 4-16ohm.. another channel also 4-16ohm...thank you for sharing

[@reynaldoreyes6435]

Thank very much for this video clip.now i understance the function of this impedance to the amp n speaker

[@5trezip23]

Great video. Thank you so much.

[@BlondynCh]

omg this stuff makes my head spin

[@accidentkilla1265]

True that

[@chkao59]

I see! Thank you!

[@hondayamaha3]

thankyou so much. I needed this. more blessings to you

[@AREALRIDERS]

thanks on this, very helpful on us beginners like me i understand very well. i have one question. if we install two 8 ohms speakers it says total of 4ohms. is there any possible way to make it 8ohms? or not.

[@MrArvin0306]

a 4ohms resistor in series with the 4ohms, 2 x 4ohms = 8 ohms in series.

[@electronic7979]

Useful video 👍👍

[@EoCx1]

The back track music completes this video. Well done. What's the track?

[@medottariqaziz]

Your videos are awesome. I need your help today and I m sure that u r the one who can help me with. I have two speakers of 50W, 8 Ohm each. I want to make a woofer so how to wire these both speakers and what type of amplifier ( Power rating) I have to use. pls explain me about it.

[@streamallday]

"now the fun starts" love this part of the video thanks for this

[@lithe.susurrous661]

This vid is very helpful!

[@chepepancho2958]

Love your channel. everything easy to understand for the regular man. Q: I have a 100w x2 mini hifi amp that is rated for 4 to 16 ohm speakers. I have two 3ohm 300 watt Panasonic speakers, will the amp be ok if I connect the speakers to it?

[@karollepeto8924]

It will, but only if you connect them in series. Then the impedance will be 3+3=6 Ohm. In parallel they would have 1,5 Ohm which is not in the range 4-16Ohm

[@Pudin788]

thank u very much for making this video.....

[@rukshanweerasinghe1031]

Thanks ....Very clear explanation

[@notevenea8277]

Very informative, im gonna forget in 5 mins but know I can come back and listen again

[@omaradan8062]

Thanks Great video channel

[@ajithkts]

Helped me.,,, Thank you

[@devendranathshukla5848]

Thanks for wonderful information. I want to connect 8 ohms qty-12 speakers in my house. Can I? If possible what will be wiring configuration from speakers to an amplifier

[@kayumanggiako872]

Most understandable instructions ive watch

[@michaelbelfast1]

Hi, great video... I have a question... I have an integrated stereo amp with 4-8 ohm and 120 watts and a Bose 301 speaker with 8 ohm impedance at minimum 10 watts and maximum 70 watts. Is the best way to just connect the speaker to one channel on my amp, or is there a way to connect it to both channels to get more out of the speaker?

[@dannoland]

Here is a graphical way to arrive at equivalent resistance of two resistances in parallel. Draw a horizontal line near the bottom of a piece of paper. That is the ground. Draw a vertical pole coming out of the ground whose height is proportional to the larger of the two resistances. Some inches away from the first pole, draw a second vertical pole out of the ground whose height is proportional to the second resistance. So, if you are connecting in parallel, an 8-ohm and a 4-ohm resistance, one pole should be twice as tall as the other. Now draw a line from the top of each pole to the base of the other. The height of the point of intersection of the two diagonal lines above the ground is the equivalent resistance of the two in parallel. (It doesn't matter how far apart the poles are.) One important thing you can see from this method is that the equivalent resistance is always less than the smaller of the two.

[@syedkhalidahmed8045]

Good notes,📝

[@revokdaryl1]

My main speakers are Infinity RS III/B that are 4 ohm, but actually can drop down to 1.8 ohms at specific frequencies. Because of their EMIT tweeters, which I really like, I don't want to switch to a different speaker.

[@P3nguinDarknes5]

And just like that, you became my spirit animal. Wow, thanks for this Geoff!

[@PhuckHue2]

wish I would known this before running my amp to 1 ohm. it started smoking

[@angelinetecson4026]

Same for me hahaha

[@JunPTechnician]

Thank you for sharing sir new supporters here

[@garyandrews746]

4 ohm speakers draw more current, 8 ohms speakers draw less current by a factor of 50 percent less, for home theatre a set of 8 ohm speakers is realistic as you will not place as much current demands on your PSU as opposed to a 4 ohm set. 4 ohms speaker sets are for the Car Audio spectrum as these can be powered by the Car alternator when the engine is on providing the needed current and power.

[@mofojackson]

lol @ the background music. It's like department store shopping jacked up on roids and looping endlessly. but thanks for the info! :D

[@davidw64us1964]

ty for this video

[@astorina]

It would be nice to add why low résistances are not appreciated as loads , a short sentence like « at constant output power of the amp , a low resistance will increase dramatically the current and as a possible consequence the load (speaker) may heat too much and burn or the output transistors of the amp I like very much the inside view of the two types of speaker selectors , thx very much

[@RP-xs4uz]

Hi sir, this is a grear video ever .just a question sir can we apply this to combine the 2 of the same kind home theater 5.1 speakers too? godbless u

[@Andy-nh2zg]

.... ist ok beim "nackten" Lautsprecher. Beim Anschluss von Mehrweg Boxen passt die parallele Schaltung auch noch, aber bei der Serienschaltung muss berücksichtigt werden, dass nur absolut baugleiche Baugleiche LS - Boxen den Sound nicht verändern. Spannend wird es bei verschiedenen Typen! DIE FREQUENZWEICHEN ergeben zufällig einen guten oder miesen Sound bei Serienschaltung. Viel Spaß beim Experimentieren!

[@SteveOLive88]

That makes the amp happy

[@shasashu]

i have a question for the channel owner geoff and others who can answer correctly. i want to connect 2 speakers to 1 side ie. left channel and 2 speakers to right channel respectively. so talking about 1 channel only eg. left channel... my 2 speakers are rated 6 ohms impedance each. my amp is rated to accept 4 to 8 ohms. so if i put my 2 speakers in parallel it becomes 3 ohms and if i put them in series it becomes 12 ohms. so what is the simplest possible thing i can do so that the system works? i think i put two speakers in parallel and add 2 ohm resistance to the positive wire. so how to put a resistance there? i am asking as a layman. i also want to ask that do the speaker really has positive and negative polarity, so we must wire the positive to positive and negative to negative from amp or whichever side we put +ve the other side becomes negative and vice versa? pls answer.

[@Geoffthegreygeek]

Hi Shasahu, Your calculations are correct. If you don't ever run your amp at full power, then it will probably cope with a 3 ohms load at the lower power levels. Otherwise wire them in series to be safe. See my article on How to connect 2 speakers to 1 amplifier for more details. Regarding using a 2 ohm resistor: you can certainly do this. You need to ensure the resistor can handle the power from your amplifier, it is often hard to find a resistor capable of 50 watts or more. It would simply connect to the positive terminal of the amp, and then connect the speaker red wire to the other end of it. Because this can all be too much effort, most people use a speaker selector switch to do this work for them. A simple series/parallel speaker selector would be a good solution. Have a play using the different types of switches on my speaker selector switch simulator. The second simulator will also tell you how much power the resistor will need to cope with. hope this helps

[@shasashu]

Thanks for the reply. Pls share link to the switch simulator and resistor power calculator. Thanks.

[@Geoffthegreygeek]

geoffthegreygeek.com/how-to-connect-2-speakers-to-1-amplifier/ geoffthegreygeek.com/speaker-selector-switch-simulators/

[@vsmichael1]

shasashu 3 ohm might be fine, see if it works or kicks off. If it plays see how hot it gets under load a while.

[@gondokist]

(for home application) if we use an active subwoofer will it still draw power from the amplifier and still have to formulated first or just plug it in into a pairs of the socket (back L & R maybe) since it already have it own power source??

[@TheHeraldOfChange]

This was great. What about a 3 speaker system? Passive L, R & Base connected to a "two" amplifier system, i.s. amp with single L&R outs.

[@nkgrbtyoutube8852]

I like this vedio. thanks.

[@Impulsegt1]

love that cheesy background track

[@Decco6306]

it repeats so often omg

[@benedictcruz9934]

Impulsegt1 sounds very 90's

[@etherlords88]

early 90s cityscape documentary backtrack...

[@gristlevonraben]

@@benedictcruz9934 odd, it sounds 70's school film to me

[@Jenuin]

Impulsegt1 exactly. Very retro.

[@brianzimmerman4710]

I have a 2x12 cabinet and the speakers in the cab are both 8ohm speakers, do I use a head that is 16 ohms or 8ohms? not sure if they are in series or parallel.

[@tructrung9963]

Video rất bổ ích cho dân chơi âm thanh ! THANKS !!!!!

[@ananthmenon9741]

thank you

[@kingofthegoats245]

Good god the music is simultaneously incredible and painful

[@Rodape1]

Yes it is

[@jerryjohnson4625]

Something so sweet must have a thorn somewhere , lol.

[@Querencias7]

Ha! I enjoyed it as background. No problem at all.

[@davekiddie4467]

80's sitcom

[@MayureshVaidya]

Great solution. But while it talks about the impedance ..what about the watts? Suppose I need to connect 4ohm full range (15 watt) + 6 ohm (30 watt) tweeter to an amp which has 100 watt power and 6 ohm Minimum Load Impedance, per channel. Note: 2 speakers will be connected to a single channel (100 Watt/6 Ohm), so total 4 speakers(2 full/2 tweeters). So as per this video, I need to add one 6ohm resistor before connecting 2 speakers in parallel. But then should I also need to match the watts? Or should I go with the lesser watt resistor, say around (30 or 50 watts per channel).

[@ajeeshkmathew2166]

hi sir, could you pls tell me, is there any problem to connect 4 ohm speaker and 8 ohm speaker to same amplifier??

[@edwardvalenzuela5897]

yup, there is an obvious problem in there as your total impedance if connected in parallel to a single amp is only 2.6666666..ohms which could be critical as typical amplifier impedance range from 4-16 ohms unless you wired them in a 2 ohms amplifier. as much as possible, make your setup symmetrical.

[@jaygalarza1307]

So i ordered 2 subs that came with the box and amp ... im trying to figure out how to wire the subs to the box theyre both 4ohms boss cx122.... i have a 30ft speaker wire how should i wire them?

[@GeorgeGeorge-xj2bc]

One question about how an amplifier is considered,as a constant voltage source,or as constant current source?

[@samidudigital2753]

Thank you very much

[@RGV2300]

Just realize that my chinese 5.1 speakers are suffering from a mod i did 😅

[@jakob1379]

The general formula is quite simple for parallel, just show. Prod(R_i)/sum(R_i)

[@ronaldsamson8607]

Sir, Im from Philippines. And i want to ask something. I have 300w amplifier and i want to buy 4 speakers..so in one speaker how many watts do i buy.. And i want to connect in parallel connections.. Thank you sir..

[@bautistaconcon5719]

I have 6 and 16 ohms output speaker on my amplifier, how many ohms speaker should i use if I conneck 6 speakers per channel? Thank you & more power.

[@jordanb325]

Am I able to use one 6 ohm and one 8 ohm speaker for one output (and the same for the other) of a 6 ohm minimum amp? If so, would I wire in series or parallel?

[@richiesaneud2202]

Thanks you for the information . I have an idea how to use ohms...

[@nobody6803]

3 impedance matching transformer will readd more ''load'' on the amplifier to drive also it will change you're sound to since you add a passive component between the amp and speaker

[@mikook63]

In the manual for the Sansui 5000 is the following: Caution: Never attempt to use two or three 8 ohm speaker systems at the same time. For use with three speaker systems, the impedance must be more than 8 ohms each. For use with two speaker systems (A+B or A+C) the combined impedance of the systems must be more than 8 ohms. I am not understanding exactly what this means. My plan was to connect 2 pairs of Sansui SP-2000 speakers, which are 8 ohm speakers, but based on this warning I don't think I can now do this? Can you advise me? Thanks

[@JamminClemmons]

* *Mike Cook,* * You posted your comment 4 years ago. *How did this turn out for you?* I have 6 ohm home stereo speakers and afraid to hook them to my 8 ohm amp.

[@fadialkadi3697]

Can you please explain about amp with 4 channels A, b output

[@belzajon]

Sir, what will happen if you combine 2 channels of 4 ohms each (Left and Right of amplifier) to a 4 ohms speaker? Thanks!

[@sanjoy2521]

Can I connect one 4 ohms 20 Watts with another 4 ohms 10 Watts in series to make a speaker system ?

[@Condor1970]

What if you had to wire two 4 ohm component speakers in parallel because they each had built in crossovers, yet needed a total load impedance of 4 ohms? Could you add a heavy duty high wattage 2 ohm resistor inlee to increase the total impedance?

[@marcorighini6201]

Yes and in Winter time ypull get some extra heat for home