Receiver impedance question

[Vivek]

Hi all,
I have a Denon 5.1 receiver and they recommend a speaker impedance of 6 to 16 ohm for the front speakers. I am curious to know what will happen if a 4 ohm speaker is used?
Thanks.
Vivek

[Frank Berry]

If it's anything like a lot of Sony amplifiers, you'll probably cook the output devices and let out all the smoke.

[Vivek]

Hi all,
I plan to use two Vifa TC18WG49 8 ohm drivers in parallel in a TMM and a D27 6 ohm tweeter. Since the impedance is ever changing with frequency, will there be a problem?
And in MTM speakers, commercial or DIY, do they use two 8 ohm drivers in parallel or is it two 4 ohm drivers in series.
Please advice.

Thanks,
Vivek

[DcibeL]

What would possibly happen with a 4 ohm load is that your Denon reciever will overheat, and if it doesn't have any thermal protection, it could fry the power transistors, but only if you play your music loud. For example, if the maximum output power is 100 W at 6 ohms, then at 4 ohms the maximum output power will be 150 W (ideally). So as long as you don't crank your stereo past 2/3 of it's maximum output, it *should* be okay. Also remember that the lower the speaker impedance, the lesser the quality of the sound you will get from the amp.

In MTM speakers, the majority will use two 8 ohm drivers in parallel, and I would think this is due to the fact that there is a much wider selection of high quality 8 ohm speakers then of 4 Ohm speakers.

[Vivek]

My receiver does have thermal and output protection. But I don't play music very loud. Considering that, it should probably be fine.

In MTM speakers, the majority will use two 8 ohm drivers in parallel, and I would think this is due to the fact that there is a much wider selection of high quality 8 ohm speakers then of 4 Ohm speakers.

But when most MTM or TMM speakers use two 8 ohm drivers in parallel does that mean we need to check the receiver impedance range and the speaker impedance if we are considering speakers for HT. Those who are into DIY know all this but the general public may or may not know. What happens then?

Vivek