Two 8 ohms ready 13-14 ohms

[emilio]

Hey dudes, I bought a cabe with two speakers at 8 ohms 70w each, but read 13-14 through the cable in series. Is this normal? Another question is can a connect a tube head with a 4 ohm out safely? It says 4 ohms/130w min and see how these read 13-14 ohms and are rate at 70w (meaning 140w), it should be okay right?

 

[PFDarkside]

Re: Two 8 ohms ready 13-14 ohms

Speakers have an impedance rating (which is different than D.C. Resistance) DC Resistance will be ~80% of the impedance spec. Your reading is correct for 2 8 ohm speakers in series.

Regarding your tube amp, you should match speaker impedance to amplifier output impedance requirement. Yes, many will say they have mismatched for years, but it's stressing the output transformers and tubes.

 

[emilio]

Re: Two 8 ohms ready 13-14 ohms

So I should wire them in parallel to turn 8 to 4 ohms?

 

[Demanic]

Re: Two 8 ohms ready 13-14 ohms

^^
Yes, if your amp is rated to handle 4 ohms.

Sent from my MotoE2(4G-LTE) using Tapatalk

 

[emilio]

Re: Two 8 ohms ready 13-14 ohms

Thank you both very much!

 

[Securb]

Re: Two 8 ohms ready 13-14 ohms

Sounds weird. Have you gone in there and checked out the wiring? One of my cabs was reading 3 ohms and when I opened it up the previous owner had done a hack job inside. One speaker was not even connected.

 

[Darg1911]

Re: Two 8 ohms ready 13-14 ohms

Sounds perfectly reasonable to me. Wire them in parallel and your meter will probably show them in the 3 ohm range. As PF mentions, you are measuring static resistance of the voice coil, not impedance (which varies with frequency). The DCR will typically be 15% or so less than the rated, nominal impedance.

 

[emilio]

Re: Two 8 ohms ready 13-14 ohms

Thanks a lot guys. I've wired it parallel and it sounds more powerful now!