I know you steer away from whiteboards but this is definitely a case of a picture is worth a thousand words. The concept of Kirchhoff's voltage law is much more understandable when you show the complete loop.
Hi Paul, your explanation is geared more towards electronics. Let me simply for anyone who wants to know how series and parallel connections affect loudness. When you connect two speakers in parallel you get a total of 6db increase in the SPL level of a single driver at the same amp volume. 3db from doubling of power due to halving of impedance and another 3 db from the summing of sound waves from each individual driver. Connecting two speakers in series, there will be no SPL increase of the two drivers vs one driver at the same amp volume. That's because impedance doubles hence halving power which leads to a 3db decrease in SPL. The 3db increase from drivers summing cancels out with the 3db decrease from halving of power. The advantage of a series connection is you double the power handling of the drivers hence increasing the driver's maximum loudness. It also lowers distortion at high volumes since it halves the excursion required to produce sound at a certain SPL level.
Thank you so much Mr. Paul! Now it gets so much clear! Thanks! The only doubt still is going on is if it’s in parallel, the maximum wattage limit decrease in the same ratio as impedance does. But with your explaining this won’t occur! Thank you. So much! Your channel is das far as I can tell a great channel to watch every night! Cheers!
It's in the name, "impedance". Raise the impedance less wattage, lower the impedance more wattage. A series connection raises the total impedance, parallel lowers the impedance. Power is a function of current times voltage.
So what is the practical impact of the two speaker cabinets in series? Expect to need to turn up the volume to get the same loudness. Also expect the sound quality to be lower. Each cabinet is a complicated circuit with resistors, capacitors and inductors to feed the proper frequency to each driver ideally without messing up the phase of the signal to each driver. By the time the signal passes through them both my bet is the sound from the two boxes is a bit muddled. Also the wave propagation from the baffle of each driver will be interacting with each other so the chances of the image being as good are low IMHO.
@@geddylee501 When speakers are connected in parallel you will get best result (at least theoretically) by having both connected directly to the amplifier for best damping factor/behavior.
Confused question, confusing answer. A speaker marked 8Ohm 30Watts means the speaker can handle an input of 30Watts. 8Ohms is the nominal impedance and this may drop to 4Ohms at some frequencies. Connecting two 8Ohm speakers in parallel may not be a good idea as it will present a nominal 4Ohm load to the amplifier which may drop to 2Ohms at some frequencies. Many amplifiers will be unable to drive such a low impedance unless specifically designed as a high current amplifier.
Thanks for this it helped me tremendously with setting up a second centre channel speaker in series . Do you know of a solution to by pass the second speaker when it’s not required?
it becomes like a battery and light bulbs. A light bulb draws 1A with current. 2 pcs. parallel connected bulbs draw 2 A of current. But the battery must be able to deliver 2A of current or it won't work. Two 8 ohm speakers connected in parallel will be 4 ohms. yes you should get twice as many watts. but then the power supply and transistors have to handle it. This is where the problem lies. many amplifiers are unable to provide twice as many watts due to the transistor and power supply not being able to do this. and a speaker does NOT provide a constant 4 ohms but change up and down with frequency! 8 ohms often give better sound than 4 ohms.
I think an explanation of what the ''rated at'' numbers are on a speaker may be helpful? Just because a speaker has, let's say a 30watts sticker on the back, in reality that means very little. Apart from don't plug then into a 100watt amp and run them full blast. I might be over simplyfying?
Hi Paul, Usually you’re very clear. But on this topic I’m none the wiser 🤪 Maybe more nubie definitions around each of the terms you use, and like below, a whiteboard might help. 🙏
Does an amplifier put out higher voltage to higher impedance speakers? I would think there would be a max voltage dependent on the input voltage and the output voltage is a multiplier of that (minus voltage drops from volume adjustment pots) as both input and output transformers would have a set number of windings. So the max output your amp can do to 4ohm vs 8ohm speakers would be twice as much, but that is because the amp is putting out twice the current to the lower impedance speaker. P=V^2/R=IV AFA speaker wattage, connecting 2 30W speakers gives you 60W total max output no matter how you wire them. So you can output 60W to 2 30W speakers without destroying them.
I'm also confused, although my brother or dad could explain the tech stuff (both EEs) - If I bought a pair of speakers at a yard sale, could I hook them up to the same terminal post as my current speakers to have a combined sound?(i.e. twist the wires together and put them in the same hole?)
Probably depends on application. Combining speakers isn’t all that common in home audio. It’s more common in car audio and with multiple woofer set ups. Traditionally it seems best route is to connect in parallel and try to go as low impedance as possible to a point as to what the amp can handle. My friends and I experimented with both types. I tried series approach with 4 8 inch woofers in a box and I wired in series. Didn’t sound good. May have been other reasons too. Box size. Not perfectly sealed. Had another friend that was running a 2 eight inch woofer with one 10 in dual voice could sub. He wired in parallel and I believe all his were 4 ohm as well. His problem was clipping and also speaker sensitivity where volume would increase too high by slightly touching his slider level volume control. We switched to parallel setting and it was much better. I myself went to 2 10 inch subs with a 12 in middle sub. I think the 10’s were 8 ohm and the 12 dual coil coil 4 ohm. I hooked these up in parallel which I believe was 2.7 ohms per channel. Same amp. Produced more strong bass but I designed a better sealed box too.
Sorry Paul, but the 2 speakers in series explanation didn't make sense to me, as 2 8 ohms coils in series is equivalent to a single 16 ohms coil. And that falls into the 4 ohms explanation. Can you please clarify as I am really confused now? Thanks!
10 volts RMS over 8 Ohms is 10x10/8=12.5Watts. Two speakers in series is a dumb idea as you lose half the power.Rather, you can potentially get twice the power by putting the speakers in parallel and potentially that will yield a louder volume. Reality is however that you are introducing a comb filtering with doubler effects between your two speakers outputting the same signal and...for audiophile listening, this is also a dumb idea as the frequency response easily will end up being messy as the two speakers won't be exactly in phase relative to your ears.
@@Douglas_Blake Well, it's basic audio stuff. Audiophiles should stay away of doing this entirely. I'm happy with my KEF Uni-Q single-point source drivers that maintains phase integrity through the entire audible frequency response and the very opposite of that is to duplicate your speakers (series or parallel) messing up phase completely.
Question: I have some Boston HD10 speakers that I purchased new back in the mid nineties. They are advertised and labeled as "8 ohm" impedance and advertised at 90Db/W sensitivity. They were originally powered by a Pioneer VSX-4800 surround amp that was replaced recently with a Yamaha S701 2 channel integrated amp.due to the speaker outputs cutting out at any decent volume I do realize that speakers are driven with AC voltage, not DC, and that impedance isn't exactly the same as measuring static DC resistance. When I measure the DC resistance through the HD10 speaker leads, my DMM measures ~3.7 ohms. Should a speaker advertised as 8 ohm impedance measure closer to 8 ohms static resistance, or are these Boston HD10's actually lower impedance than rated by the manufacturer? This concerns me as, from what I understand, running 4 ohm speakers with an amp that is designed to break against an 8 ohm load can damage it due to higher current being required to drive the 4 ohm speakers. I'm wondering if driving these HD10's was the reason my Pioneer amp met it's demise. Any opinions?
@@jareknowak8712 Thank you for answering my question. After reading up on the subject I think running my HD10's with the S701 will be perfectly fine with the amplifier impedance switch set to high, 8 ohms. I'm using a powered sub in addition, and I don't listen at very loud volumes.
@@Douglas_Blake Thank you for your input, makes good sense. So far so good, my HD10's with the powered sub sound great with the S701. The unit only seems to be emitting minimal heat through the convection cooling vents on the top. But like I said before, I'm not listening at very high volume levels, let alone for a prolonged period of time. I have common wall neighbors, so my volume levels are limited, but I did "de-couple" the sub and speakers from the floor so as to mitigate potentially disturbing my neighbors. What I like is that it sounds really good without having to play at a high volume level.
Don't do it. They both have problems. Think about it, your speakers both go up and down in current needs at different impedances because you're playing 20hz to 20kz. Now they both are sometimes spiking in power needs and sharply dropping together. In parallel they're doing it in sync so what I just said above. In series, it's more averaged out but now there's a lot more resistance to the current. Your single channel only has half the total voltage of your amp and voltage pushes the current. So now your sound quality is shit because even if you have the power you can't move it effectively and it still might be difficult when the speakers impedance dips. It'll dip less but still be giving your amp a suicide mission.
If you also are wondering what if I use 2 bridged ampa to run speakers in parallel or series to it gets even worse. Because when you bridge the output it can't handle lower impedances even more. The power does but so does the impedance.
Hey Paul, I think I get the part about ohms, volts and watts but the bit about the light bulb got me confused. A light bulb usually takes 110 volts. Not 10. I'm stumped.
You dont put 110v AC into a speaker !!! You put 110v into the supply of the amplifier then the power supply circuit of the amplifier drops the voltage to around +40v to -40v DC. Then the amplifier circuit creates an AC voltage based on the small input voltacge from a source The output voltage of an audio amplifier is obviously much lower.
Red wire from the amplifier goes to speaker 1, pin 1. Blue wire goes to speaker 2, pin 2. 3rd wire (inside the speaker cabinet) goes from speaker 1, pin 2 to speaker 2, pin 1. That's series. Red and blue wires from the amp are both splitted inside the speaker cabinet (Y cable) - so every speaker gets a red wire to pin 1 and a blue wire to pin 2. That's parallel.
It's confusing because some sensitivity pseudo-units and "nominal" impedances are confusing. A sensitivity in dB/W is self-explanatory and don't change with impedance, whereas "dB for 2,83 V" is [...]. Why 2,83 V ? I subtract 3 dB/W for 4 Ω speakers that use that strange convenient unit (dB for 2,83 V???). I subtract 3 dB/W again for "8 Ω" speakers that don't have enough minimum impedance (80%) and behave like 4 Ω speakers. ¿What is a 4...8 Ω speaker? Minimum impedance for an eight ohm speaker should be around 6,4 Ω. Parallel connection will drop the impedance and increase current and wattage. Serial connection will drop tension for each driver (voltage divider) and increase impedance, therefore increasing volume to reestablish tension of each driver will increase current and wattage demand too. In conclusion (I might be wrong): more drivers, more wattage and current; less real sensitivity in dB/W, more power that the amplifier will have to supply.
@@Douglas_Blake Exactly although I don't know if it's fair or not. The amp will try to keep the voltage stable, therefore a four ohm speaker that declare a pseudo-sensitivity of 90 dB for whatever voltage (2,83 V usually) will draw the double of power than an eight ohm speaker. Measured with a more accurate unit, one will have a sensitivity of 90 dB/W and the other 87 dB/W, which will reduce the confusion of some "reviewers" that have to change sensitivity perceptions on the fly.
@@Douglas_Blake No they aren't because current and power drawn from amplifier aren't the same. John DeVore rant was very interesting and funnier than doing the calculations. dB/W is a technical unit useful for comparisons, whereas "dB for 2,83V" is like comparing apples and pears or max. speed of cars in mph or km/h without telling which is the unit. For four ohms in the "new version", the voltage should be 2 volts to be equivalent to an eight ohm speakers. Which speaker has the highest sensitivity, the 8 Ω speaker with 90 dB for 2,83 V, or the 4 Ω speaker with 90 dB for 2 V? The last one is a fair comparison to me, and even more clear if we write that the first one is 90 dB/W and the second one 87 dB/W.
@@philipslighting8240 It's what I think, basic science is not that difficult. Understanding how an audiophile can connect many speakers in parallel or only one with four ohms or less impedance without increasing current and power requirements, which is like creating energy from nothing, that's way more difficult. Reviewers: "these two speakers have the same sensitivity and phase for one particular frequency, but the amp struggles with one of them"; that non sense is difficult to understand.
@@Jorge-Fernandez-Lopez What has a so called audiophile got to do with basic electrical theory ?. I am an electrical engineer is just basics not difficult.
Howdy. No intention to be a wise guy. If one doubles the voltage to a series one will get double the total wattage and hence double the volume. To get the same wattage one needs to deliver sqrt2 times the original voltage. Regards.
Nice try, but this comment adds more mud to this muddy river. Doubling the power (wattage) does not double the volume (loudness). All other things being equal (excluding the voltage, current and impedance that must be changed in some way to change the power), doubling the power will increase the volume (loudness) by about 3 decibels (dB). For most people to say that something is "twice as loud", you need about 10 times the power, or + 10 dB. [Assuming same signal type, same speaker, same distance, same room, etc.]
Yes, one big problem with what was said is that if you double the impedance and double the voltage, the sound level from the system doesn’t stay the same. What does stay the same would be the current, and the wattage (and sound output) per driver. But now you have 2 drivers, so the total amount of sound from the combination of the 2 drivers will be 3 dB louder. You doubled the voltage and kept the current the same, so the total wattage fed into the combination of drivers was doubled.
