OHM's puzzlement on my Onkyo 609

[smccran]

Hi,
I've been reading through the settings for my new Onkyo 609 and came across the Ohms settings options.

In the managemnt screen I can switch between 4ohms and 6ohms, but I'm running a set of Mission 77 5.1's which all say they have a 'nominal impedence' of 8ohms.

What should I be running the Amp at? (4 or 6) and can I expect to notice any difference?

Thanks
Shaun

 

[dennis1]

good question, also the same on my 607, settings only for 4 or 6 ohms. who's got the answer.

 

[smccran]

Bump?

 

[dreamtime1976]

hello

i think i can answer this... in page 46 of the manual we can read...

Speaker Impedance
(European, Australian and Asian models)
`4ohms:
Select if the impedance of any speaker is 4 ohms or
more but less than 6.
`6ohms:
Select if the impedances of all speakers are between
6 and 16 ohms.

 

[smccran]

Hi,

Thanks, I'd ready that but wondered what impact that will have on the speakers.

I'll double check my settings.

Thanks
Shaun

 

[Sniper]

What this setting does is place a resistance (generally in the form of a transistor) in series to each speaker output to limit the current draw from the amp's power supply - the idea here is to offer some protection (to amp and tweeters) when using generally low impedance speakers with the amp.

The "correct" setting is 6 .... practically always! ... choosing the other setting means you've mismatched the amp and the speakers, as low impedance speakers need good power-supplies. Don't kick yourself if you've made this mistake - I've seen "pros" (mags & shops) suggesting some very mismatched speaker/amp sets!

 

[smccran]

Hi,

Thanks for that, it makes a bit more sense now.

Cheers
Shaun

 

[logiciel]

good question, also the same on my 607, settings only for 4 or 6 ohms. who's got the answer.

Well the manual has the answer for one - in several places, page 43 among others.