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Hi audiophiles/videophiles,


I have a Kenwood vr407 reciever which puts out 100 watts per channel at 8 ohms. It came with the matching wattage/ohmage speakers.


It does have B speaker terminals too. I was hoping to use the B terminals for outdoor speakers.


I have an old pair of Mission bookcase speakers 15-75 watts at 6 ohms.


Can I hook up the lower ohm Missions to the larger ohm Kenwood reciever?


What about larger ohm speakers to lower ohm reciever?



I really appreciate your help.




Rollie
 

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You can do exactly that.



All I have to offer in the way of caution is, be wary of the load that you are putting on your receiver. This can damage your receiver and underpowered speakers are frequently the first thing to go in a system that is pushed to and beyond its limits.



Also remember that if your receiver is rated at 100 watts per channel at 8 ohms then a speaker rated at 4ohms can pull as much as twice the juice. If I was adding speakers i would DEFINITELY make sure the add ons were as easy to drive as possible.



I used to have the VR510 at 110wpc and was greeted to a nice smell when I decided to crank a little volume out of my new 6 ohm speakers with a 4 ohm center after changing from a setup that was all 8ohm speakers.



I wouldn't normally caution too much, but you said they would be outside and those speakers can easily be pushed beyond the limits due to the vast amount of space of the "outdoors".




An alternative would be a cheap little two channel amp and the room B outs on you reciever.....I actually recommend this alternative over your first option. I know that some of the prices of two channel amps are scarey, but considering that from the wording of your post you sound like you don't want to go into too much financial bother with this and your not overly worried about purity of sound a little two channel shouln't be that much.



Hope I helped....:)



I haven't looked to see what "cheap" is in two channel amps....so I'll look for you and report my finding in a few minutes:D
 

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Let me explain it with a quick lesson in Ohm's Law, which states that one volt will push one ampere through one ohm. What does this mean in audio?


Voltage is the output from an amplifier, measured between the speaker terminals. The impedance (resistance) is measured in ohms, and is what limits the flow of current. (No resistance is a direct short circuit.) The resulting current flow, in amperes, when multiplied by voltage, produces power, measured in watts. This, by the way, is Watt's Law.


Now, what is relevant to you is this: the amps output voltage varies with the volume control (and, of course, the audio signal itself). The current flow, and thus the wattage, at a given volume setting, depends on the impedance (resistance to the flow of current) presented by the speaker (which actually varies with the frequency), but the rating is an average).


A six ohm speaker will allow a bit more current to flow than an eight-ohm speaker will at the same volume setting, which naturally makes the amp run slightly warmer. (Remember: volts x amps = watts) Theoretically, as long as you don't overheat the amp, you can run any impedance speaker. The lower the impedance, the lower the volume before reaching that point.


Most amps will parallel speakers when set to use both pairs, which results in a very low overall impedance, and high current (and thus wattage (heat)), but a few connect them in series, which presents a higher overall impedance and lower current and wattage.


You can usually tell by the warning given by the manufacturer when running two speaker pairs. If it says something like "A or B, 4 - 8 ohms" / "A & B, 8 ohms min", then they parallel, and you must limit the volume you try to achieve when running both speaker pairs.


You can usually tell by feeling the amp every 15 minutes or so how hard you can drive the amp, and most modern amps will go into protect mode (i.e., cut off temporarily) when overheated or overdriven. Moderation is the key.


Oh, by the way, to answer your last question, if the speaker impedance exceeds that of the amp, it will simply run cooler.
 

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I just checked. And due to your application(outside,low-mid quality,low-mid power), you can literally spend whatever you like from $50 on up to the much talked about $125,000 Krell two channel all singing all dancing wonder amp:D Of course if you were to go that route....one's sanity would need questioning. LOL!!
 

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lantern - ygm
 
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