needin some help with my new 2500

[parkerbender]

it says to set the impeadance levels before you power the unit on, is that a life or death thing? i plugged in my set of little cheap yamaha spekers into the left and right channels last night when i first cracked the box open, but didn't really crank it up much or anything, and now, when i go to set things up, i saw the warning, that won't really do serious damage will it, also, i cannot, absolutely cannot find anything which says what the impeadance is of these things, they're fron a yht-440 series HTIB, whould i assume they are 6 ohm or eight? what difference will it make, i know 6 ohms are harder to drive, but what does it do in the reciever when you switch? thanks for the help!!!!
-parker

 

[Cygnus]

Set it to (if it isnt allready) 8Ohms and leave it. Your system will be fine

 

[parkerbender]

okay, wow.

fricking cool gui, i cant wait to get four more speakers and really pimp this thing out now i only got a 6.1 setup, and i left the sixth out for 5.1

 

[rschleicher]

Yeah, it's not only fine to leave the switch in 8-ohm mode, it's preferred, regardless of the impedance of your speakers. The 4-ohm setting just lowers the power supply rail voltage, thereby trying to limit how much thermal "trouble" you might get into by driving low-impedance speakers real hard. But, it actually increases the chance that you will get clipping on short-term transient peaks, which in my opinion is a bigger problem to avoid. If you call or e-mail Yamaha tech support, they will also tell you to use the 8 ohm setting for any speaker.

 

[abc3]

Similar impedance question - Ohm L speakers(!)

I too just bought an RX-V2500. It may sound crazy, but since I'm rebuilding my system for the first time since college (early '80s), I'm still using my beloved 25-year-old Ohm L speakers. They're rated as "8/4 ohms"; apparently the impedance is 8-ohms at some frequencies and drops as low as 4-ohms for others.

I actually spoke to a guy at the Ohm speaker company (during a call about getting a replacement for a failed driver), and I asked him about it. He recommended the 6-Ohm setting. Per contrast, the guy down at the boutique shop where I purchased the receiver says to use the 8-ohm setting.

From this thread, it sounds like it really won't matter, long as I don't crank up the volume to clipping in either case (hardly likely until I spring for new speakers).

Any other advice? I mainly want to protect the new receiver (though I supect it has its own speaker current overload protection).

Thanks,

Ash Collins

 

[MDS]

Those switches are there in order to obtain UL approval. If you set it to 4/6 Ohm, it will reduce the rail voltage, thus reducing the amount of current the receiver can supply. This is to protect the receiver from overloading quickly when trying to drive low impedance speakers.

The impedance of all speakers varies with frequency. If the speaker's stated impedance is 8/4 Ohm it means that the 'nominal' impedance is 8 Ohms and it may dip as low as 4 - pretty much standard for most speakers. Using the 4 Ohm switch will reduce the power available to the speaker but protect against overload. For 8 Ohm nominal speakers, you definitely want to leave the switch at 8 Ohm.

Even when you are using 4 Ohm nominal speakers, it's usually best to just leave the switch at 8 Ohm and just be cautious with the volume control as 4 Ohm nominal speakers are harder to drive than 8 Ohm nominal speakers.