[richgrohl]


Hi newbie here, just like to ask opinions of experts here or anyone who has knowledge when it comes to matching impedance of speakers and receivers. I recently acquired a Pioneer SP-BS22 bookshelf speaker and a Harman Kardon 3390 stereo receiver.

The thing is when I purchased these units I was only looking at the wattage rating and totally had no clue that I should have also considered the impedance rating. So here comes my question, would these two device work without any problems?

Because while trying to research about ohms matching I've read that I shouldn't be using a speaker with lower ohms than the amplifier. However I'm not quite sure if I understand it correctly that is why I would like to ask your opinions if whether these two will work without any issues.

 

Below are the specifications of my speaker and receiver. 

Any info would be much appreciated, thanks in advance!


 

Pioneer SP-BS22

Frequency Range	55Hz-20kHz
Impedance	6 ohms
Sensitivity	2.83 V: 85 dB
Input Power	80W
Crossover	3kHz
Magnetically Shielded	No

 

 

 

Harman Kardon HK3390

Stereo RMS Power	80W per channel x 2, into 8 ohms
No. of Channels	2

 

[Jack D Ripper]


If you look at the manual of the Harman Kardon HK3390, it says it is fine with 4 ohm speakers.  So your 6 ohm speakers should be no problem at all.

 

[richgrohl]


Thanks for your input. But basing from the manual I can see that at 8ohms it is using 80w and at 4 ohms it is using 100w. And since my BS22 speakers are rated 6ohms I'm assuming it will use about 90w, am I correct?

However my BS22 only have specs of 80w, will it have problems when my receiver drives it at 90w? (assuming my guess is right)

Continuous Average Power (FTC):

80 Watts per channel, 20Hz – 20kHz,

@

 

[Jack D Ripper]


The ratings tell you what the manufacturer says the thing is capable of doing.  The amount of power that is actually output at any moment is a function of several things, including the input level and the volume control.  (Other things affect this, too, like bass and treble controls, loudness compensation settings, etc.)  Most of the time, you are probably having it put out less than 1 watt per channel, except when playing very loud.  Assuming your speakers are properly rated, you would have 85dB at 1 meter whenever your receiver is actually putting out 1 watt.  That is pretty loud, though not ridiculously so.

 

Now, another thing worth mentioning is that there is no standardization for power ratings for speakers.  So they basically are virtually meaningless in most cases; the only way they can be meaningful is if the manufacturer explains precisely what they mean.  Most likely, they mean that the speaker can handle that amount of power for a short period of time without being destroyed, though how short of a time that is could matter if one wanted to push things to their limits (which, by the way, is not a good idea).  And it probably cannot handle that amount of power as a pure test tone at one frequency.

 

Here is what you should do if you want to find the maximum safe volume for your stereo (though it may be too loud to be safe for your hearing).  Put on some music that is at a fairly constant level.  Slowly turn up the volume control, until it starts to distort audibly, then turn it down until you hear no distortion.  That is the maximum safe volume your stereo can play.  Keep in mind, that does NOT mean that you will always be safe with the volume control at that setting; remember, the output is a function of several things, including input level, so anything that is at a higher input level would push things too far at that volume setting.  This, by the way, does not tell you whether the limit is the amplifier or the speaker or both; but in all cases, if it distorts, you should turn it down.  If you want something that plays louder, you need different speakers, different amplification, or both.

 

 

In most cases, with 2 channel receivers (or multichannel receivers when using only 2 channels), the receiver will actually be capable of slightly more power than the manufacturer claims for continuous output.

 

 

You do not need to worry about an amplifier being capable of putting out more power than a speaker can handle, if you use things sensibly.  For many years, I ran some speakers with a receiver that is rated for about twice as much power as the speakers were rated as being capable of handling.  Basically, if I ever turned things up to the point of distortion, I turned it back down again immediately.  As long as you do that and use good judgement, you should have no troubles with this.

 

And you should follow the same approach if an amplifier is rated as being less powerful than a speaker is rated as being capable of handling.  If an amplifier is pushed too hard, it will distort, typically putting out high power into high frequencies, which can destroy tweeters.  But, again, if you do as I say and use good judgement and don't ever listen at levels that cause distortion, you should be fine.

 

 

About terminology:  A receiver is a tuner (radio), preamplifier (AKA control amplifier, which is the part with input selection, volume control, etc.), and a power amplifier (the part that drives the speakers), all in one box.  An integrated amplifier is a preamplifier and power amplifier in one box.

 

 

 

So, the long and the short of it is this:  That receiver is fine to use with those speakers.

 

[afrogt]

It doesn't really matter if its 80, 90 or 100 watts. You actually use a lot less power than you'd think.


You just want a receiver that can handle 6 ohm loads and since that HK can drive 4 ohm loads it'll have no problem with the Pioneer BS-22 speakers.

 

[richgrohl]


Wow! thanks Jack for a very detailed explanation. I really appreciate the effort you put in writing that very helpful guide. Good stuff!

Also thanks afrogt for your input as well. Now that all my doubts are cleared I can't wait to set up my Turntable system. Once again thank you!