Does anyone know what reputable companys make 2ohm components? I know JBL makes 2ohm coax's, but I was curious if anyone makes a good 2 ohm component speaker. Thanks.
WRX/Z28
When you have an 8ohm driver, 4 ohm driver and a 2 ohm driver, and they are all 90dB/2.83V/1m efficient, what's the use of having 'more power' on 2ohm drivers when the output *voltage* of the amp stays the same compared to a 4 or 8ohm driver?
Speaker-impedance/amplifier-output-impedance drops --> less control
Amplifier output current rises --> more heat
Amplifier output wattage rises --> Amplifier input current rises
Am I the only one that doesn't see the use?
greetingz,
Isabelle
Speaker-impedance/amplifier-output-impedance drops --> less control
Amplifier output current rises --> more heat
Amplifier output wattage rises --> Amplifier input current rises
Am I the only one that doesn't see the use?
greetingz,
Isabelle
In there you'll see from top to bottom, and then left to right. Xtant 2200ix I won in an xtant sales contest years ago. PPI PC650, A1200, A404, A600.2, A300.2, Proart50, A404.2, Xtant 2200ix I got used,soundstream Ref500sx, US acoustics USX2050, PPI 4200am (not pictured is the 2150m), AX400, A404, A404.2, A600.2, (in my car is a white A300.2), Concept 97.2 eq and Orion nt200bix's, NT200 (looks like 4, but one is an empty sink to replace the scratched one), 250HCCA, 425HCCA, MTX rt4240 and Audio art 240.4x. Also not pictured are a few more us acoustics on the way, a few hifonics series vii and viii, a fultron 16-mx220-4, and a few amps I am selling.
Hmmm... #1, where did you find 16ohm speakers? Every set I've ever seen, including some higher end stuff like B&W, Martin Logan, Mirage, Sonus Faber, Vienna Acoustics, were all 4-8ohm.
#2, how is it the same output? When you run most amps at lower impedence, they make more output, hence the reason they draw more current from the battery.
#3, never judge a speaker on efficiency. If anything, some of the worst sounding speakers I ever heard were highly efficient, and some of the best sounding were so inneficient, it would make you shake your head.
#4, with 16ohm speakers, you are leaving power on the table. If you're amp was spec'd out to run at 4ohm by the designer, and he intended it to see that load, why would you run higher? I can tell you i've heard quite a few sub setups that were wired series to give an 8ohm mono load accidentally to an amp that was supposed to see it wired to 2ohm, and the subs sounded terrible and ran out of gas before making any kind of bass. Swap wiring on the same amp and the subs loved life.
#2, how is it the same output? When you run most amps at lower impedence, they make more output, hence the reason they draw more current from the battery.
#3, never judge a speaker on efficiency. If anything, some of the worst sounding speakers I ever heard were highly efficient, and some of the best sounding were so inneficient, it would make you shake your head.
#4, with 16ohm speakers, you are leaving power on the table. If you're amp was spec'd out to run at 4ohm by the designer, and he intended it to see that load, why would you run higher? I can tell you i've heard quite a few sub setups that were wired series to give an 8ohm mono load accidentally to an amp that was supposed to see it wired to 2ohm, and the subs sounded terrible and ran out of gas before making any kind of bass. Swap wiring on the same amp and the subs loved life.
1. 1973 B&W DM2a
2. When you put 2.83V on a speaker and it gives you 90dB's of output, why would you pick another speaker that gives you 90dB's of output at 2.83V but needs 2 times the current from your amp?
3a. A speaker that has a peak of 92dB at one specific frequency when you put 2.83V on it, but gives only 85dB on 3/4th of the useable frequency range won't be as loud as a speaker that 'only' has an efficiency of 90dB/2.83V/m, but over a broad band of its useable range.
3b. Efficiency doesn't tell a thing about how a speaker sounds, neither does impedance or power handling.
4. Why would Technics (1976 the time they made real high end stuff) put '4-16 Ohm' on the backside of the amp, when it only works best at 4ohm?
Good subwoofer manufacturers *will* mention that the specd efficiency on DVC subs is measured with the coils parallel. When you put them in series, each coil will only get half the voltage, pretty obvious you'll notice that... Same thing when you start to wire speakers/subs in series.
greetz,
Isabelle
2. When you put 2.83V on a speaker and it gives you 90dB's of output, why would you pick another speaker that gives you 90dB's of output at 2.83V but needs 2 times the current from your amp?
3a. A speaker that has a peak of 92dB at one specific frequency when you put 2.83V on it, but gives only 85dB on 3/4th of the useable frequency range won't be as loud as a speaker that 'only' has an efficiency of 90dB/2.83V/m, but over a broad band of its useable range.
3b. Efficiency doesn't tell a thing about how a speaker sounds, neither does impedance or power handling.
4. Why would Technics (1976 the time they made real high end stuff) put '4-16 Ohm' on the backside of the amp, when it only works best at 4ohm?
Good subwoofer manufacturers *will* mention that the specd efficiency on DVC subs is measured with the coils parallel. When you put them in series, each coil will only get half the voltage, pretty obvious you'll notice that... Same thing when you start to wire speakers/subs in series.
greetz,
Isabelle
By the way, I think npdang is faaaar from being a dumbass?
http://www.diymobileaudio.com/forum/showthread.php?t=31
http://www.diymobileaudio.com/forum/showthread.php?t=31
1. How are you still running 35y/o speakers? Have they been "re-coned"?
2. Maybe that speaker has a wider dispersion pattern? Maybe it has a more solid response? Maybe it's made of a garbage can lid, and sounds horrible. I love my mirage 8ohm home speakers simply because they sound great from anywhere in the room. 360 degree dispersion pattern, (180 degree from front and rear mounted drivers)
3a, not sure where you were going with that one.
3b, I highly agree.
4. Technic's did that so they wouldn't exclude anyone's speakers, but even technics back then would have suggested running lower impedence than 16ohm if it was available as an option.
Having sat through a few amp manufacturer's trainings, i've never heard one designer/engineer tell me to run higher impedence.
Even running 8ohm svc subs off the same amp vs. 4ohm svc subs has the same result, the 8ohm sounds underpowered. I've done it before because some manufacturers shipped the wrong impedence sub in the carton, and I had to use what was available till I could swap it for the customer.
5. I'm no engineer, so you might have to explain why you keep using 2.83v as a reference. I have about 20 years of practical experience in both home and car audio.
2. Maybe that speaker has a wider dispersion pattern? Maybe it has a more solid response? Maybe it's made of a garbage can lid, and sounds horrible. I love my mirage 8ohm home speakers simply because they sound great from anywhere in the room. 360 degree dispersion pattern, (180 degree from front and rear mounted drivers)
3a, not sure where you were going with that one.
3b, I highly agree.
4. Technic's did that so they wouldn't exclude anyone's speakers, but even technics back then would have suggested running lower impedence than 16ohm if it was available as an option.
Having sat through a few amp manufacturer's trainings, i've never heard one designer/engineer tell me to run higher impedence.
Even running 8ohm svc subs off the same amp vs. 4ohm svc subs has the same result, the 8ohm sounds underpowered. I've done it before because some manufacturers shipped the wrong impedence sub in the carton, and I had to use what was available till I could swap it for the customer.
5. I'm no engineer, so you might have to explain why you keep using 2.83v as a reference. I have about 20 years of practical experience in both home and car audio.
1. Nope, they've been always in the hands of people that have treated them with respect, also, they don't have foam surround.
2a. "Maybe that speaker has a wider dispersion pattern? Maybe it has a more solid response?" That's exactly what I was telling in '3a'
2b. So you're saying all 8 ohm drivers are garbage and all 2 ohm drivers are high end?
2c. I like the fact you really have to sit exactly in the sweet spot with my B&W's, because in that sweet spot, I have very very detailed staging, but they still sound nice when you are somewhere else in the room (except behind the speakers). It's a matter of taste.
3a. See above
3b. Pretty logic
4. I had a Marantz PM7200KI before that was 'made for' 8ohm speakers, why did it lack detail and control compared to my Technics that is 'made for' 4ohm speakers, while the Technics should be worse when I read your explination? Also, when I had the Marantz amp, I wanted to get a subwoofer, with the technics, the sound is more neutral but very very deep. I tried some active subwoofers when playing with the Technics annd I didn't find one that actually added some value to the sound, and believe me, I tried some high-end ****...
5. Check the link I posted right beneath the post you're replying to
greetz,
Isabelle
2a. "Maybe that speaker has a wider dispersion pattern? Maybe it has a more solid response?" That's exactly what I was telling in '3a'
2b. So you're saying all 8 ohm drivers are garbage and all 2 ohm drivers are high end?
2c. I like the fact you really have to sit exactly in the sweet spot with my B&W's, because in that sweet spot, I have very very detailed staging, but they still sound nice when you are somewhere else in the room (except behind the speakers). It's a matter of taste.
3a. See above
3b. Pretty logic
4. I had a Marantz PM7200KI before that was 'made for' 8ohm speakers, why did it lack detail and control compared to my Technics that is 'made for' 4ohm speakers, while the Technics should be worse when I read your explination? Also, when I had the Marantz amp, I wanted to get a subwoofer, with the technics, the sound is more neutral but very very deep. I tried some active subwoofers when playing with the Technics annd I didn't find one that actually added some value to the sound, and believe me, I tried some high-end ****...
5. Check the link I posted right beneath the post you're replying to
greetz,
Isabelle
2b. where did I say that at all? if anything, you're saying that 32ohm speakers should sound better than your 16's, so why not just go get a ceramic resistor and bump them up? More resistance is better right? I don't get it.
4. Could have had to do with your wires, power filtering, environment, or it could just be that the amp was a pos. IE, that's like me saying "Why did my components sound worse off this pyramid amp at 2ohm than they did off my PPI at 8?" The amp is entirely different, but when comparing the same amp, with the same speaker, just different impedences, i'd chose lower and extract all available power out of the amp. Keep in mind, 12v amps are different than home amps watt for watt.
5. I read the link, and he's definately on point, except for above stated post.
4. Could have had to do with your wires, power filtering, environment, or it could just be that the amp was a pos. IE, that's like me saying "Why did my components sound worse off this pyramid amp at 2ohm than they did off my PPI at 8?" The amp is entirely different, but when comparing the same amp, with the same speaker, just different impedences, i'd chose lower and extract all available power out of the amp. Keep in mind, 12v amps are different than home amps watt for watt.
5. I read the link, and he's definately on point, except for above stated post.
2b. I don't say higher impedance is better for the sound, or at least, not noticeable. I do say, just like npdang says in that thread I found after giving my opinion, that it's better for the amp (even for a 0.25ohm stable one) and for the power system of the car.
Putting a 16ohm resistor in series with my speakers whould be cutting the voltage they're getting in half, while a 32ohm speaker directly on the amp will get the same voltage.
4. The only way to compare the same amp on the same speaker(s) with different impedances, is by using multiple coils (DVC/QVC subs or multiple SVC subs). When you wire 2 coils in series, they both get half the voltage compared to when you wire them parallel, so you're cutting the efficiency of the speaker(s) in half, the amplifier gives exactly the same output voltage...
By the way, Marantz versus Technics is more like Audison VRx versus Genesis, not like Pyramid versus PPI. It's both higher end stuff, but with different sonic signatures. Or are you one of those people that doesn't believe in sonic signatures of amps?
greetz,
Isabelle
Putting a 16ohm resistor in series with my speakers whould be cutting the voltage they're getting in half, while a 32ohm speaker directly on the amp will get the same voltage.
4. The only way to compare the same amp on the same speaker(s) with different impedances, is by using multiple coils (DVC/QVC subs or multiple SVC subs). When you wire 2 coils in series, they both get half the voltage compared to when you wire them parallel, so you're cutting the efficiency of the speaker(s) in half, the amplifier gives exactly the same output voltage...
By the way, Marantz versus Technics is more like Audison VRx versus Genesis, not like Pyramid versus PPI. It's both higher end stuff, but with different sonic signatures. Or are you one of those people that doesn't believe in sonic signatures of amps?
greetz,
Isabelle
2b. It might be the same voltage, but again, voltage doesn't drive speakers, current does. Also, my .5ohm stable HCCA's and ProArt would sound particularly terrible at 16ohm.
4. That's not the only way. There are many car subs that are available in different impedences for the same exact speaker with the same exact specs. Example. JL audio 12w3v2d2 vs. 12w3v2d4 vs 12w3v2d6. Dual 2ohm vs dual 4ohm vs dual 6ohm.
I definately beleive in sonic signatures of amps, they do sound different. I was exagerating the point, amps sound different not because of the load they are running, (that affect power output more than anything), but because of the way they are built and the componentry used.
Again, I don't care how many volts are going through my speaker, in the end current is what moves it, and more current is attainable through lower impedence on most amps. Think of voltage like water pressure, and current like water volume. I want more water, not less at a faster pace. Give me a firehose, not a water pik.
4. That's not the only way. There are many car subs that are available in different impedences for the same exact speaker with the same exact specs. Example. JL audio 12w3v2d2 vs. 12w3v2d4 vs 12w3v2d6. Dual 2ohm vs dual 4ohm vs dual 6ohm.
I definately beleive in sonic signatures of amps, they do sound different. I was exagerating the point, amps sound different not because of the load they are running, (that affect power output more than anything), but because of the way they are built and the componentry used.
Again, I don't care how many volts are going through my speaker, in the end current is what moves it, and more current is attainable through lower impedence on most amps. Think of voltage like water pressure, and current like water volume. I want more water, not less at a faster pace. Give me a firehose, not a water pik.
Not sure if you'd consider them "nice" or not, but most Infinity components are 2 ohm. They really give more like a 3 ohm load, but they're officially rated at 2 for some reason.
Not to derail the derailment or anything...carry on
Not to derail the derailment or anything...carry on
2b. Current is directly in relation to voltage
4. When you check the efficiency of JL audio subs, you'll see that they don't use dB/2.83V/m but dB/W/m. The numbers of a D2 compared to a D4 and compared to a D6 are quite the same. Conclusion, when you would convert the numbers to dB/2.83V/m, you'll see that they have a completely different efficiency, so actually, it are completely different subwoofers
Voltage doesn't go trough your speakers, it's on it and causes current to go trough it.
You want to compare deebeez with amount of water? Fine....
You can't compare a speaker with a waterhose, you have to compare it to a waterhose with some holes in it. The waterpressure that goes in is the voltage that your amp delivers, the water that comes out on the other end are the deebeez, the efficiency is the amount of holes in the hose...
When you have a big hose that gives you 90liters of water in one minute when you put 3 bars of waterpressure at the beginning or you take a smaller hose that also gives you 90liters of water in one minute when you put 3 bars of waterpressure at the beginning, the amount of water you're getting from the same waterpump will be the same.
But the bigger hose will have more holes in it, so you will spill more water (current from your powersystem) than with the smaller hose with less holes in it, so the pump (amplifier) has to work harder to give you the same amount of water (deebeez)...
When you have a pump that's stable enough to work hard, what would you do, put 1 big hose full of holes on it that will give you 90liters of water per minute and let the pump work at full power all the time, or put a smaller hose without holes on it that gives you the same 90 liters per minute, but makes the pump have reserve enough to add more small hole-less hoses on it that each will give 90 liters per minute with the same pressure?
When you have an amplifier that's stable enough to run 2 ohms, what would you do, put 1 2 ohm speaker on it that gives you 90dB/m, or put a 4 ohm speaker on it that gives you the same 90dB/m, but makes the amp have reserve enough to add more speakers on it so you can rise the efficiency of the speakersystem with the same 2.83Volts?
greetz,
Isabelle
4. When you check the efficiency of JL audio subs, you'll see that they don't use dB/2.83V/m but dB/W/m. The numbers of a D2 compared to a D4 and compared to a D6 are quite the same. Conclusion, when you would convert the numbers to dB/2.83V/m, you'll see that they have a completely different efficiency, so actually, it are completely different subwoofers
Voltage doesn't go trough your speakers, it's on it and causes current to go trough it.
You want to compare deebeez with amount of water? Fine....
You can't compare a speaker with a waterhose, you have to compare it to a waterhose with some holes in it. The waterpressure that goes in is the voltage that your amp delivers, the water that comes out on the other end are the deebeez, the efficiency is the amount of holes in the hose...
When you have a big hose that gives you 90liters of water in one minute when you put 3 bars of waterpressure at the beginning or you take a smaller hose that also gives you 90liters of water in one minute when you put 3 bars of waterpressure at the beginning, the amount of water you're getting from the same waterpump will be the same.
But the bigger hose will have more holes in it, so you will spill more water (current from your powersystem) than with the smaller hose with less holes in it, so the pump (amplifier) has to work harder to give you the same amount of water (deebeez)...
When you have a pump that's stable enough to work hard, what would you do, put 1 big hose full of holes on it that will give you 90liters of water per minute and let the pump work at full power all the time, or put a smaller hose without holes on it that gives you the same 90 liters per minute, but makes the pump have reserve enough to add more small hole-less hoses on it that each will give 90 liters per minute with the same pressure?
When you have an amplifier that's stable enough to run 2 ohms, what would you do, put 1 2 ohm speaker on it that gives you 90dB/m, or put a 4 ohm speaker on it that gives you the same 90dB/m, but makes the amp have reserve enough to add more speakers on it so you can rise the efficiency of the speakersystem with the same 2.83Volts?
greetz,
Isabelle
2b. wrong, while voltage stays the same, current increases as resistance decreases.
It works more like this. The speaker it more like a fire that you are trying to put out with the hose. You are consuming water from the hose by spraying it on the fire. If you have a water pick, operating at 150psi, and then you have a firehose operating at 150psi, which do you think will put the fire out fastest? They're both operating at the same "voltage", but the larger water supply is key here. Such is current from an amplifier, and since current increases when resistance decreases, and current drives the speaker, an amp running at a lower impedence makes more current, therefore I'd like to run a 2ohm speaker, and maximize the amount of current available.
I'd liken this to trying to flood your street with a fire hydrant, would you leave a little resistance by keeping the fire hydrant cap on partially, or would you remove resistance by opening it fully, if the goal were to flood your street as quickly as possible?
Again, if what you were saying were the case, then you should definately look for some 32ohm, or even 100ohm speakers. You can maximize "your" sound quality this way. Any way you slice it, when you lower impedence, the amplifiers output increases. I'd like my amp to run as powerfully as possible... i'll let my volume control dictate how hard my amp is working.
It works more like this. The speaker it more like a fire that you are trying to put out with the hose. You are consuming water from the hose by spraying it on the fire. If you have a water pick, operating at 150psi, and then you have a firehose operating at 150psi, which do you think will put the fire out fastest? They're both operating at the same "voltage", but the larger water supply is key here. Such is current from an amplifier, and since current increases when resistance decreases, and current drives the speaker, an amp running at a lower impedence makes more current, therefore I'd like to run a 2ohm speaker, and maximize the amount of current available.
I'd liken this to trying to flood your street with a fire hydrant, would you leave a little resistance by keeping the fire hydrant cap on partially, or would you remove resistance by opening it fully, if the goal were to flood your street as quickly as possible?
Again, if what you were saying were the case, then you should definately look for some 32ohm, or even 100ohm speakers. You can maximize "your" sound quality this way. Any way you slice it, when you lower impedence, the amplifiers output increases. I'd like my amp to run as powerfully as possible... i'll let my volume control dictate how hard my amp is working.
All I know is that despite my headache from reading 4 pages of this, after seeing the pic of your amp collection, I now have a massive erection.
I'll stop arguing, dB/W/m is only the same as dB/2.83V/m with 8ohm drivers. On 4 ohm drivers dB/2.83V/m is actually dB/2W/m, on 2 ohm drivers it's dB/4W/m...
I always work with/convert to 2.83V, because then impedance is unrelevant and you don't have to think how much wattz or amperez the amp will deliver.
Other people work with dB/W/m, fine if they know what they are doing, it's more difficult, but fine...
Other people don't believe in sensitivity, headroom, speakerimpedance/amplifierimpedance-ratio... and just want more wattz by getting low impedance drivers...
No problem, my answer: RE XXX, waste of power, but it's 2 ohm and sounds pretty good...
greetz,
Isabelle
I always work with/convert to 2.83V, because then impedance is unrelevant and you don't have to think how much wattz or amperez the amp will deliver.
Other people work with dB/W/m, fine if they know what they are doing, it's more difficult, but fine...
Other people don't believe in sensitivity, headroom, speakerimpedance/amplifierimpedance-ratio... and just want more wattz by getting low impedance drivers...
No problem, my answer: RE XXX, waste of power, but it's 2 ohm and sounds pretty good...
greetz,
Isabelle
Where did I say that you *should* pick a high impedance, high efficiency speaker, and even choose it based on that specs only?
I guess reading isn't something you're great at?
I just said, when you have 2 speakers that sound equally good, the one has an impedance of 8 ohm and the other one is 4 ohm, the 4ohm version being louder just because it gets more wattz from the same amps is not always true!
You know that 2.83V on an 8 ohm speaker is 1Watt, and on a 4 ohm speaker, its 2Watt, right?
You know that doubling the Wattz equals a 3dB increase of output, right?
When you have those 2 equally good sounding speakers that both have an efficiency of 89dB/2.83V/m, I hope you realise that the 4ohm (being 89dB/2W/m efficient) speaker won't get louder on the same amp than the 8 ohm speaker (being 89dB/1W/m efficient).
The 4 ohm speaker will get 2 times the Wattz of the 8 ohm speaker, but it also needs double the wattz to spit out the same deebeez!
By the way, I gave you an answer, RE XXX, but I also gave you my opinion of getting 2 ohm drivers, just for the sake of getting more wattz out of your amp.
Just like I now give my opinion about: "I know a few of my amps would run best at a 2ohm load"... My opinion: "********"...
Again, I tought this forum was all about cutting the crap? Too bad some people can't live without the crap
greetz,
Isabelle
I guess reading isn't something you're great at?
I just said, when you have 2 speakers that sound equally good, the one has an impedance of 8 ohm and the other one is 4 ohm, the 4ohm version being louder just because it gets more wattz from the same amps is not always true!
You know that 2.83V on an 8 ohm speaker is 1Watt, and on a 4 ohm speaker, its 2Watt, right?
You know that doubling the Wattz equals a 3dB increase of output, right?
When you have those 2 equally good sounding speakers that both have an efficiency of 89dB/2.83V/m, I hope you realise that the 4ohm (being 89dB/2W/m efficient) speaker won't get louder on the same amp than the 8 ohm speaker (being 89dB/1W/m efficient).
The 4 ohm speaker will get 2 times the Wattz of the 8 ohm speaker, but it also needs double the wattz to spit out the same deebeez!
By the way, I gave you an answer, RE XXX, but I also gave you my opinion of getting 2 ohm drivers, just for the sake of getting more wattz out of your amp.
Just like I now give my opinion about: "I know a few of my amps would run best at a 2ohm load"... My opinion: "********"...
Again, I tought this forum was all about cutting the crap? Too bad some people can't live without the crap
greetz,
Isabelle
That's a nice example of some good marketing...
"Sensitivity: 92dB"... 92dB measured how?
1 Watt? If so, very nice sensitivity, but probably not at that price, otherwise they should mention it...
2.83V? That's only 86dB/W/m and a nice example of wasting Wattz!
"Frequency response: 35Hz~30kHz"... from a 6.5" component system? maybe at -10dB? They don't mention it...
Rated power handling of 55W, but claiming it can handle up to 220Wattz...
...with a high-pass crossover frequency of 200Hz and a 24dB/oct slope?
...for 0.01second?
...in a sealed enclosure of 5 liters?
.....
They don't mention it...
"Carbon-Glass Fiber Honeycomb Woofer"
"Water Resistant Paper Midrange Material"
Do they even know from what material the cone is made? Carbon or paper? They mention both
Nice piece of marketing... Worthless specs... Reminds me of B(l)ose, wonder if they sound any better
greetz,
Isabelle
"Sensitivity: 92dB"... 92dB measured how?
1 Watt? If so, very nice sensitivity, but probably not at that price, otherwise they should mention it...
2.83V? That's only 86dB/W/m and a nice example of wasting Wattz!
"Frequency response: 35Hz~30kHz"... from a 6.5" component system? maybe at -10dB? They don't mention it...
Rated power handling of 55W, but claiming it can handle up to 220Wattz...
...with a high-pass crossover frequency of 200Hz and a 24dB/oct slope?
...for 0.01second?
...in a sealed enclosure of 5 liters?
.....
They don't mention it...
"Carbon-Glass Fiber Honeycomb Woofer"
"Water Resistant Paper Midrange Material"
Do they even know from what material the cone is made? Carbon or paper? They mention both
Nice piece of marketing... Worthless specs... Reminds me of B(l)ose, wonder if they sound any better
greetz,
Isabelle
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