Axiom Home Page Forums General Discussion Stereo Impedence 4ohms vs 8 ohms

Hi! I bought 2 speakers that have 4 Ohms Impedence (written on the back of the speaker) but my stereo receiver is a 15 years old JVC 8 Ohms to 16 Ohms. My question is: Can I use these speaker with my receiver without doing any damage?
Thank you for your answers!

Just offhand without any further info i'm going to say....no.

I would agree...

What could happen?

Your receiver could very quickly overheat and fry, because it likely doesn't have the heatsinks or protection circuits necessary to deal with the excess current driving 4 ohm speakers.

This isn't to say it will happen, but I wouldn't take the chance.

In general I'd say it would turn itself off as all good electronics that output that much power should have fault control, but a 15 year old receiver that's rated for between 8 and 16... I'd be a bit nervous about that one. Might not be a big deal at low volumes, but I would be nervous without any knowledge of the receiver's circuitry.

Mass, unless you're just going to sit there and watch your new speakers instead of listening to them, you've got to try something. I have no idea whatever what protective circuitry, if any, JVC receivers had 15 years ago, but frankly I would take a chance to try and find out. Start out at low level and see if the receiver gets hotter than with whatever speakers you've been using up to now. If not, increase the level and check again,etc. I assume that you don't have a JVC manual which might discuss the situation.

Hi mass,

To amplify (no pun intended, heh, heh) JohnK's comments, gradually increase the volume as you check the heat radiated by the receiver. It should get no more than warm to the touch. If it gets hot after driving your 4-ohm speakers for an hour or so, I'd say you're likely risking either blowing the output stage or thermal shut-down.

Protection circuits of various types have been around a long time. An early solid-state amp I built in the late '60s (a kit) had thermal sensors on its output transistors to shut down the receiver if it got too hot. Without seeing the impedance curve of the speakers, it's hard to know whether the curve just touches 4 ohms at one frequency or remains there over a good part of the spectrum. If it were the former case, the JVC might drive them with no difficulty.

Regards,