What I would like to know:
Could it hurt when i use a amplifier with 2x 110W (4ohm) output on 2x (3ohm) 80W-RMS 240W-peak 3-way speakers?
What i already found out:
Impedance differantiates, but in most cases, the lowest possible impedance of the speaker is advertised.
What am i using?:
2x JBL Club 9630 6 x 9 inch speaker
Amplifier (class D): BA100 TPA 3116*2 Breeze Audio
Some extra info:
I have a 72W powersupply currently, which limits the max power output of the amplifier by about 35W / speaker. But when I think I need more power, for example: a 160W powersupply, do i need to worry about the impedance? Or is the difference between 3 and 4 ohm negligible?
Thanks in advance!
Could it hurt when i use a amplifier with 2x 110W (4ohm) output on 2x (3ohm) 80W-RMS 240W-peak 3-way speakers?
What i already found out:
Impedance differantiates, but in most cases, the lowest possible impedance of the speaker is advertised.
What am i using?:
2x JBL Club 9630 6 x 9 inch speaker
Amplifier (class D): BA100 TPA 3116*2 Breeze Audio
Some extra info:
I have a 72W powersupply currently, which limits the max power output of the amplifier by about 35W / speaker. But when I think I need more power, for example: a 160W powersupply, do i need to worry about the impedance? Or is the difference between 3 and 4 ohm negligible?
Thanks in advance!
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You are correct that the impedance of the loudspeaker differs - it changes with the frequency of the signal. You are wrong in thinking that it is the lowest possible impedance that is advertised. The advertised figure is called the 'nominal impedance' and you could think of that as being an 'average' value across the frequency range. At certain frequencies the impedance of a speaker can fall below or rise above the nominal value.
I will now look at your extra information.
JBL Club speakers are car speakers. Car speakers are usually 4 ohm nominal impedance, but for some reason JBL specs each of the Club series at 3.0 ohm.
https://www.jbl.com/on/demandware.s...2/pdfs/JBL_Club_Speaker_SpecSheet_English.pdf
Your Class D amp is specified to work into 4 ohm and I see no reason why it will not be happy with the type of speaker it is likely to be used with i.e. car speakers such as the JBL Clubs.
In other words, you have nothing to worry about regarding matching.
https://www.jbl.com/on/demandware.s...2/pdfs/JBL_Club_Speaker_SpecSheet_English.pdf
Your Class D amp is specified to work into 4 ohm and I see no reason why it will not be happy with the type of speaker it is likely to be used with i.e. car speakers such as the JBL Clubs.
In other words, you have nothing to worry about regarding matching.
If you look at the impedance versus frequency curve for this nominally 8 ohm speaker, you can see that, for most of the time the impedance is greater than 8 ohm.
Similarly, for most of the time, the impedance of your JBL will be greater than 3 ohm.
Your JBLs are a bit more complicated than shown in this curve, but I hope this sets your mind at rest!
Similarly, for most of the time, the impedance of your JBL will be greater than 3 ohm.
Your JBLs are a bit more complicated than shown in this curve, but I hope this sets your mind at rest!
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Further investigation suggests that JBL specify their car speakers as 3 ohm because the majority of car amplifier power outputs are specified at 2 or 4 ohm.
That is, 3 ohm sits nicely in the middle to satisfy the owner of any car amplifier.
I suspect the 3 ohm spec has more to do with marketing than matching!
That is, 3 ohm sits nicely in the middle to satisfy the owner of any car amplifier.
I suspect the 3 ohm spec has more to do with marketing than matching!
The 3ohms is actually a harmon kardon group marketing drivel.
They claim they make the speakers 3ohms to allow for the resistance of the cars speaker wiring of 1ohm.
They claim this then means the car amplifier will see the correct 4ohm load.
Whatever :rollseyes:
Don't forget hk bought out a snot load of companies in the late 80's.
They claim they make the speakers 3ohms to allow for the resistance of the cars speaker wiring of 1ohm.
They claim this then means the car amplifier will see the correct 4ohm load.
Whatever :rollseyes:
Don't forget hk bought out a snot load of companies in the late 80's.
Further investigation suggests that JBL specify their car speakers as 3 ohm because the majority of car amplifier power outputs are specified at 2 or 4 ohm.
That is, 3 ohm sits nicely in the middle to satisfy the owner of any car amplifier.
I suspect the 3 ohm spec has more to do with marketing than matching!
Thank you really much, i have been struggling with this for over a week now. Did you find the impedance graph of the 9630?
The JBL specs I have found do not include an impedance versus frequency plot. Since the 9630 is a three-way speaker including crossover components, its impedance variation will be more complicated than that of the single driver I showed you earlier. This will result in more more 'ups and downs' on the impedance plot. Your combination of amp and speaker is not unusual and you should not concern yourself regarding the matching.
I agree with your observations JM and didn't expect to find an impedance plot.
Fortunately Marnix appears to be no average car speaker buyer as he realised there could be an impedance matching problem.
He had even taken the trouble to undertake some prior research on loudspeaker impedance before seeking reassurance through this forum.
As a new member, I hope he will return for advice in the future.
Fortunately Marnix appears to be no average car speaker buyer as he realised there could be an impedance matching problem.
He had even taken the trouble to undertake some prior research on loudspeaker impedance before seeking reassurance through this forum.
As a new member, I hope he will return for advice in the future.
Yes, it could. Will it? I don’t know. It depends on how good the amp is. A nominal impedance of 3 Ohms means it probably dips down to around 2 Ohms and over the entire bandwidth it is lower than what your amp is rated at. Different amps handle that differently.
Some 8 Ohm rated amps will go into protect basically as soon as turned on if you have a 4 Ohm nominal load. Some will play for a little while and then release the magic smoke. Some will play fine unless turned up. Some, even though not rated for it, will play without any issue whatsoever.
My guess, given that it’s a cheap class D amp, it won’t like it. It might not break but you will most likely get at least significantly higher distortion. And there is still a chance you could burn it out.
Some 8 Ohm rated amps will go into protect basically as soon as turned on if you have a 4 Ohm nominal load. Some will play for a little while and then release the magic smoke. Some will play fine unless turned up. Some, even though not rated for it, will play without any issue whatsoever.
My guess, given that it’s a cheap class D amp, it won’t like it. It might not break but you will most likely get at least significantly higher distortion. And there is still a chance you could burn it out.
The comparable Breeze Audio DP1 (2.1) amp also uses TPA3116D2 chips just like the Breeze Audio BA100 under discussion, and is said to be 3 ohm capable.
breeze audio dp1 2.1 2x50w + 100w tpa3116d2 hifi digital amplifier Sale - Banggood.com sold out
These specifications support my opinion.
(In addition, the 2.1 version can drive a 2-16 ohm subwoofer.)
breeze audio dp1 2.1 2x50w + 100w tpa3116d2 hifi digital amplifier Sale - Banggood.com sold out
These specifications support my opinion.
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