Great interview Steve. Andrew Jones is a very respectable man in the industry with lots of knowledge. I enjoy listening to him and although I've been into car audio and video for a long time, I'm always learning new things from him. He seems like a real cool person.
I liked the discussion. It helped me understand many of the factors associated with the impedence spec. It comes down to how much current the driver, receiver or amp, can produe before overheating its components. At 4 ohms a speaker will draw double the amps as a 8 ohm (minimum) speaker. The power supply in the amp must be able to produce enought power to support all channels. So those multi channel AV receivers have to have stout power supplies.
*Thanks a lot for this I was hanging on every word, we really need more people like this setting it straight on the disappear down a rabbit hole mythologising misinformative internet!.*
That was an AWESOME interview Steve. Great questions and really fun answers from Andrew J. Hopefully many will watch to learn all about speaker impedance etc.
8:30 - Solid state amps offer voltage control. A tube amp is basically a current source; those impedance humps will also show up as humps in the amplifier/speaker frequency response!
Thank you for a great explanation Andrew Jones! I've wondered about these specs for some time. Just make sure you have a good amplifier and you can drive any speaker!!
It has nothing to do with a good amplifier (whatever that means). Some speakers need more current and your job is to buy one to match that speaker. If your speaker doesn't need a high current amp you are wasting money because a high current design costs extra, all else being equal.
Thanks, this was very helpful. I now understand my 8 ohms Bowers and Wilkins speakers (minimum 4 ohms) should have actually been rated 5 ohms, that is, if they would follow convention.
For amplifiers, maximum power transfer is dictated by matching the amplifier output resistance with its load, i.e. maximum power transfer occurs when the load resistance = output resistance. All deviations from maximum power means not maximum power ie quieter = frequency response. Where a speakers resistance at a particular frequency is extremely high, then the amplified sound will be quieter = frequency response. If the resistance at a particular frequency gets near to 0 Ohm, then you are essentially shorting out the output of the amplifier, which means that the output stage of the amplifier could well exceed it's maximum power handling rating leading to a catastrophic failure. Just to make it a bit more complicated, the human ear has it's own frequency response, meaning that altough an amplifier may be amplifying a particular frequency relatively quietly, the human ear could be more sensitive at that frequency meaning that the sound would be percieved as not being quieter.
I can't say I learned anything. But I'm glad you made this video. Would love to watch more videos on the subject. maybe it will sink in eventually. thank you
Even though I only understand about 2% of what these guys are talking about, I could listen to them all day. Maybe then I'd understand 3%. I wish I had been an Electrical Engineer...
this is so easy to understand. he touches on simple power transfer voltage vs current aka velocity vs pressure against a capacitive load. he says nothing on the subsequent insuctance produced by the moving coil ie power generation that then feeds back ie back EMF. then damping factor etc and source impedance of the amplifier output stage etc...
@A. Melbs well, what can I say? Thank you. Humbly. This is fundamental to physics, imagine an equilateral triangle.. each point represents a parameter. So, in this example... voltage, current and mass. In physical engineering it is usually Velocity, Pressure and Mass. These terms and principles are synonymous. You can only ever fill up the area with the triangle by 2/3rds. NO EXCEPTIONS. It is always a compromise and you design based on what works best for the application in the real world to human beings. Notice how its a triangle.. and its 2/3rds... this is not a quantifiable number. it is infinite in its recurrence. EXACTLY. I'll leave you with that thought.... 😏
@A. Melbs i missed your sarcasm initially. i have no qualifications at all yet I have taught myself Electrical Engineer and Organic Chemistry myself. some credit is deserved i think.... ps... humbly I hope you learned from my other comment as this IS simple to understand. nobody explains it from the root level thats all.
What I need to know is whether and how the impedance curve of a driver well above fs is affected by enclosure design or horn loading v.s. direct radiating. Around fs these things are pretty clear but I haven't seen any discussion of the rest of the range.
Best thing to do if you’re not sure if a speaker will be overdriven with a certain combination of impedances is just to listen for distortion. In a live sound/music performance situation, look at the excursion (how far the cone is going in and out).
i have a bluetooth speaker harman kardon play 2 and the speaker is blown out,i read the specs of the harman kardon and it says Input Impedance250mV/>10k ohms..the original blown out speaker was 4 ohms my question is can I replace it with an 8ohm rated speaker looking at the amps specs? Thanks
Electrical impedance and resistance are measured in ohms. An ohm of impedance is the potential difference (voltage) in volts across the impedance per unit of current in amperes (or amps) through the impedance. In short, an ohm is the number of volts per amp. For an 8-ohm loudspeaker, the nominal ratio of voltage to current is 8. (I say "nominal" because the true impedance varies with frequency, but the audio industry usually calls a driver whose voice coil dc resistance is between about 6 and 8 ohms an 8-ohm speaker.) If you prefer, you can think in terms of the reciprocal of an ohm, which is called a siemen. Given that an ohm is the same as a volt / amp, its reciprocal (a siemen) is an amp / volt. Therefore, an 8-ohm speaker is also a 1/8-siemen speaker, and thus, an 8-ohm impedance will have 1/8 of an amp through it for every volt applied across it.
Apparently some receivers have an Ohm switch. It turns out that how these receivers switch between 4, 6 or 8 Ohms is by cutting the power output. So if your receiver outputs 170 watts at 8 Ohms and you switch to 6 Ohms, the output drops to 100 watts. That switch is only supposed protect the system rather than power your speaker at its rated ohm rating. So it is suggested to run the receiver at 8 Ohms to ensure you get the full power output. So long as your system doesn't overheat, you should be fine regardless of Ohm rating on the speaker.
Other way around, as the Impedance goes down the watts go up from an amplifier. My mono amp Alpine HDA -M80 is rated at 500w x 1 @ 4 ohms or 800w x 1 @ 2 ohms. It also allows me to power a JL w7 @ 3 ohms. It should be 650w x 1 @ 3 ohms ((800-500)/2 =150) and then factor in 12.5v instead which is ~500w @ 3 ohms. Unless you have perfect battery and alternator.
Hi, I'm looking at the JBL 28-1 and JBL 28-1L. My amplifier is Yamaha PX8. Can someone advise on if there's any real difference in choosing any of the two. Someone told me the distance between the amp and the speakers matters and impact the decision. The distance between my amp and the 4 speakers is about 50ft
Ah!! SO this is why older Infinity speakers are known as amp killers, lol. I have a set of ELAC B5 speakers and my cheap Mono price tube amp DOES NOT LIKE THEM!! lol. My NAD on 7125 on the other hand has no problem at all. Thanks for the video!!
If I connect a 50 watt 8 ohm resistor in series with a 8 ohm speaker, measure vols across resistor, then sweep from 10 hz to 20 khz will I be able to calculate impedance at different frequencies?
So a 4ohm speaker can be driven by a 8ohm amplifier so long as the volume is not loud enough to require more power from the amp than its capable of producing. And if the volume is too high, it could cause issues like overheating? Also, If I have a 4 ohm speaker like a KEF C75 with a 4 ohm amp would actually sound better at the same volume than a 4ohm load speaker driven by an 8ohm amp? ? Does my question make sense?
I have two 8 inch , full range , handmade, DD patented speakers tested and working on 1 and 2 ohms. They are in wood floorstand transmission boxes, 1.5 meter high. Powered by handmade germanium amp on 10 watts.
I'm currently DIY'ing a pair of speakers for my first foray into tube amplifier's, also DIY. Trying to create a flat resistive load, also with impedance phase at 0 degrees. My understanding is speaker phase also dictates the demand on the amplifier, but not really much info of people chasing perfect impedance phase. If anyone here could explain the benefits of impedance phase being flat, that would be really interesting.
is this also applicable on center speakers and/or its surround speakers? lets say I have Onkyo 656 and I want to use the emotiva airmotiv c2 for my center speaker which is rated at 4ohms can you say that its safe to pair it, also my fronts will be the emotiva airmotiv t2 which also a 4ohms impedance speaker.
You're good either way. In general its no problem driving a lower impedance amp into a higher impedance speaker as long as the difference isn't too great. The problem comes in when people drive 8 or 6 ohm amps into lower load speaker such as 4 ohms or less and that is what Andrew is trying to explain at the end. Doing this will make the output stage of the amp to work even harder or put more strain on it potentially causing damage in the short or long run.
So if a speaker is rated 4 - 8 ohms you can use 4 ohm setting or 8 ohm, is that right ? I'm thinking tube amplifiers because they have 4 and 8 ohm ports .
Hell, I very much would like an experts advice to settle a debate I’m currently having with other guitarist. An amp I own (1973 Pro Reverb) rated at 4 ohms 40watts. Has two 8 ohm 12” speakers wired in Parallel for 4 ohms total. I wanted to take a 16ohm 150watt speaker. Use a resistor of 8ohm 100watts. Wired in parallel with the speaker. My multimeter showed 5.7ohms. Now take that and add it to one 8ohm speaker, wire both in parallel like the amp was designed.. that should be safe for the amp and speaker correct?
I have 6 ohms speakers and i am connecting them in parallel so two speakers in parallel gives 3 ohms and my amplifier is rated to 4-8 is it ok to run those speakers at 3 amps ?
These “audiophiles” won’t give you a straight answer. It’s only one ohm difference. Just don’t go nuts and you’ll be fine. Most 4 ohm amplifiers can easily run 2 ohm speakers. (Within reason) Most 8 ohm amplifiers can easily drive 4 ohm loads. But if you’re driving them hard and heavy, you’re going to burn the amplifier out. Keep a close watch on how hot the amp gets. If you have to turn it up to max volume, you simply need a bigger amp.
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
So I have a full setof JAMO 4ohm speakers. Now that my 15 year old Yamaha has died, Time to get a new AVR. To get the lowest THD should I replace with 8ohm speakers? Is the extra cost of speakers worth going from 10% to under 1%THD. ( lots of AVRs researched ..rough figures). Opinions?
i only need to look at the vendors spec sheets. though at this stage i wont be getting a low end AVR and trying to drive it at its max levels but a better specd unit, so that any resemblance to "LOUD" is not near the top of its range.
i just want to know how 3 way speakers are 3 different speakers using just 4 Ω or 6Ω? I've done the math and it seems like with 3 speakers in series or parallel you would either have a higher ohm or lower ohm then 4 or 6Ω. I've opened up a 3 way center speaker that has 2 mids and a tweeter and the wires were in parallel but the speaker box was labeled as a 8Ω speaker all together and i want to know how because 3 8Ω speakers in parallel would be 2.67Ω and in series 24Ω not 8 ohms
Then there is the issue of the 1 ohm Apogee Scintillas... (For those who don't know the Scintillas had a reputation for putting amplifiers "out of commission".)
Almost purely resistive load. You just needed a solid state amp capable of high current into low impedance with excellent heat sinks or fans. Like a class A Krell or a pair of monoblock Krells. You could have used two stereo amps and had one channel run the bass ribbon, and one run the mid/tweeter ribbon per speaker too.
Based on Andrew Jones figures, given for a minimum International nominal impedance of a loud speaker, examples 8 ohms is 6.4 ohms, 4 ohms is 3.2 ohms, that would calculate to a 20% minimum rather than the 8% that was stated in the video. Please explain.
.5 ohms for my Infinity 9 Kappa :}. Luckily the salesman didn't let me purchase the so-called 200 watt per channel Pioneer amplifier and instead insisted that I purchased the 200 watt per channel Harman Kardon Citation amplifier... at Double the cost of course! I rocked that combo for 12 years and was quite pleased.
I'd be more concerned if the speaker has an uneven impedance curve, driving it with a tube amp! Since a tube amp outputs a constant CURRENT for a given input voltage, the peaks and dips in impedance will show up as corresponding peaks and dips in the frequency response.
I'm looking into building my own speakers. Line array. This very subject has been very confusing for me. But after watching this video - I remain confused.
Remember a line array is essentially a nearfield speaker. Most of what your ears hear is one one set of drivers at ear level with the others canceling out many of the early reflections. The best line source speakers start to roll off the driver volumes 4 inches above seated ear position and some will roll off the lower drivers to improve imaging.
That’s great but what about cartridge impedance or for that matter all the other impedance measurements in HiFi? Apparently everything has an impedance which supposedly affects what we hear. Flipping nightmare!
There are no absolutes in audio but rule of thumb: to maximize voltage /signal integrity between sources to preamps to amps always have the load higher in impedance than the source. Its normal here to see the load being higher in impedance by factor of 5 - 10. But for speaker and amp, we want to maximize power transfer and here we want impedance to match as much as possible. But if you're going to mismatch safely, again always have load (speaker) higher in impedance then the source ( amp). But here we want to not mismatch by more than double is rule of thumb, otherwise you won't get close to the manufacturer rated power. When the load/speaker is higher in impedance this is mainly to protect the amp/receiver but also sometimes the best tone is when the amp is driving a higher impedance speakers.
I think Andrew is defending his 4ohm speakers because they've necessitated a 4ohm design to raise efficiency... Truth be told this increases the possibility of early wear and or damage to amps eceivers designed around a 6-8ohm min. specification. How much wear or damage varies, but the fact that it becomes a possibility makes it a potential problem... Always stick with proper ohms match-ups if you value your equipment and want to use it without volume limitations.
I have been deigning speakers since 1975 and they are all 4 ohms. I have had amps for 20 years and no problem at all. I have compared the same design at both 4 and 8 ohm and at the same volume and 4 ohm sounds better. Much more lifelike.
A 4 ohm design doesn't increase efficiency. It draws more current from the amp. Most receivers are not rated for 4 ohms because they don't contain enough cooling(heat sinks etc) for long term rating. In the real world most speakers will only dip into 4 ohms in a narrow range of frequencies, if at all and not continuously so there is usually not a problem. There is the occasional speaker that may be rated at 4 ohms and dips into the 1 ohm region. These are usually high-end designs and not powered by $400 receivers at any rate, so once again, it shouldn't be a problem. A seasoned audiophile knows about these speakers( Apogee Scintilla, Infinity Kappa 8,9 etc.). Designing a speaker to be a 4 ohm design is the smart way to go as most ss amp designs put out the most wattage in this impedance range range.
I clearly remember laughing so hard I farted when I read the Cnet review of Elac’s UB5 , which I own....the simple travesty of common sense encouraged many to ignore their own ears and believe only a big watt amp could bring out the best in those bad boys...Andrew just babbled his way into the facts...to your credit Steve I get it and use a NAD 316 BEE with the UB5’s ...they sound fabulous
@14:07 mr Steve seems surprised by the ability of a simple receiver to push power thru 2 ohms loads :}. that was cute. very nice interview, thanks for sharing. *most receivers i came across have the specifications mr Jones was talking about: on the last page of electrical specifications in the manual, they list "dynamic power", the term used most of the times. the back panel says 8-16 ohms, but the engineers tested the components down to almost a short circuit.. yes, the THD does go up from let's say 0.1% to 1%... i enjoy tinkering/working with (even 30yrs old) receivers because the power source in those is more than capable of driving 2 channels at the rated power; literally using 2 out of the 4, 6, 8 channels it was designed for, gives the power source a lot of headroom. i rarely replace the rectifying caps in old receivers but i do in regular amps, especially bass guitar amps (i guess heat and power demand). if you've never heard an old school yamaha receiver running a set of low impedance speakers in 'pure direct' pls buy yourself one for $50 and see how clean it runs even above 80% rated power. it doesn't have to be yamaha, any 'high end' model/brand will behave the same...
Oh, then my favorite speaker manufacturer Mart.in Logan is a liar liar pants on fire. My speakers (Source) are rated at 6 ohms but at about 7 kHz they drop to just over 1 ohm!!! Whenever I've played Chicago's If You Leave Me Now it has shut down every receiver I've ever tried to drive them with right at the beginning of the track with that triangle strike!!!!
martin Logan started making ESL's that needed high voltage swing amplifiers to drive them right. Then they hired a Krell engineer to make them work well with high current capable solid state amplifiers. That is the version a low current capable receiver has trouble with.
GET THE FUCK OUT u little shit :)))) Romania is in UE and has the best growing economy in Europe in 2017. u freaking idiot, my salary is bigger than yours for sure
i raul not my truck shit stain they where changing poles near my house. So fuck you poor boy. I have klipsch forte3s 3000 us a piece . Again fuck you poor 💩 boy.
My amp is rated to 4 ohms. Dont ask me what it do if it drives a Andrew Jones speaker rated at 4 ohms when it goes below the 4 ohm rating for those brief periods.
Yet another Steve waste of time vid. Yah never actually turn on any sound system,speakers, & why I go to OCD Mikey. I just ordered a new XLi 3500 to power my vintage Peavey SP 118x 18" Subwoofers rated at 500, 1000RMS &2000 Peak. They are 8 Ohms but I plan to upgrade for Techno Trance reason to a 20 Htz-200 Hz 1000 Watt RMS I would like double the Wattage rating of a given speaker. If I go with a 4 ohm speaker I gain extra wattage for my comfort zone, persay? I am thinking 4ohms produces more ~HEAT~ than does 8 ohm meaning wear & tear will happen sooner,damage, burnout,etc. Thus far I have heard that 4 ohm gives a 3 db overall VOLUME increase, so that means less Volume Gain is needed, would that also mean less $$$ too E Bill? My D9 15" Cerwin Vega used 4 ohm Woofer, so I stink I wills just follow that routed stinking because those D9 Speakers taught me 15" Woofer is the only way to get a good full, deep, impactfull sound. & Klipsch teached me Horns are the only way to go for Mids & Highs.. So dat B Y I loves me Martin Audio 15" Blackline X Speakers powered By's a GX7 & lovely it tiss... Steve
This is an example of why people get turned off by hifi. You guys make it seem like you need a Phd to get into hifi. If Apple had made their products this complicated to understand, Apple would have gone out of business a long time ago. But they did the smart thing: simplify. The audiophile community goes in the opposite direction: "Let's make it as daunting, complicated, esoteric, and intimidating as possible!"
So you would have one of the worlds great speaker designers just hide under a rock? Or should he not even have expert knowledge in the first place? It’s not like you have to pass a test on this stuff. There are plenty of cat videos for you to watch.
Sorry Jones you get an F in electrical engineering 101. You completely left out the phase angle, that is the reactance or power factor. This is critical and explains why a certain brand of speaker wire many years ago was notorious for blowing up power amplifiers. What's more the impedance of speakers increase when voice coils get hot because copper has higher electrical resistance at higher temperatures resulting in thermal compression. When the voice coil moves out of the linear region of the magnetic field impedance also changes. Another change comes with ferrite core inductors as increased current saturates the B-H curve. Audiophiles want simple answers to complex questions. Don't feel badly Andrew. From all the people I've met either personally or on line in this industry all have little or no real technical knowledge. So what is the meaning of the equation Z = R +X? What is a Bode plot. Why are multi way speakers not zero phase systems and what does that mean?
@A. Melbs Voice coil temperature can fluctuate as i explained above. As current flows when the driver is pushed harder its electrical resistance rises causing less current to flow and the driver not playing as loud as it should. Tweeters are especially vulnerable to this because they have many turns of fine wire which heats easily. The temperature increases with the square of the current. Therefore not playing as loud as it should its high frequency response falls off. When it cools down, if it hasn't been damaged it goes back to normal. This is one of a number of reasons why I reengineered many of my speaker systems to use multiple tweeters to share the load. So in my best sound system my speakers have 20 tweeters per channel. This reduces heating by a factor of 400 and precludes the possibility that they will ever burn out from being driven too hard or overheating which can deform or even melt the voice coil.
impedance is not that important, blah blah... i guess it is darn imprtant if you burnt your 30 yrs old cabasse 4oms woofer in 3-way speaker and all you can find around is only newer 8ohm versions...
