Speaker impedance question

[theskintman]

Hello all,

I've just picked up a pair of Wharfedale Glendale 3XP. They have a nominal impedance of 6 ohms. I have an EL34 PP tube amp with taps for both 4 and 8 ohms, but not for 6. I've done a bit of reading, but want to make sure I don't blow up my amplifier before connecting them!

As I understand it, I could connect them to the 8 ohm taps, but would be losing out a bit on the sound, but connecting to the 4 ohm taps would overwork the tubes and is bad news. Long-term, I think I should solder in a couple of 2 ohm resistors, but again, being new to all this, not really sure.

My speaker's stats are below:

Nominal impedance: 6 ohms
Max input 40 watts
Sensitivity 86Db

Thanks for the help

 

[Hartono]

Posted by theskintman :

"I could connect them to the 8 ohm taps, but would be losing out a bit on the sound, but connecting to the 4 ohm taps would overwork the tubes"

I think it works the other way around, go with the 4 ohm tap. You might think that you lose a little bit of max power output, but speaker is not resistive, so at some frequency the amp is dissipating more than the impedance looks. also as a bonus you might get lower distortion as well, since the tube see a lighter load compared to 8 ohm tap connection.

 

[tinitus]

Isnt it the other way round ...... I am no expert but would think that you will save the tubes when connecting 6ohm speakers to the 4ohm tap

 

[theskintman]

Just as well I asked! I read on this page

"On tube amps, lowering the impedance increases the workload on the tubes, which often makes the amp sound fatter but does so, alas, at the expense of reducing the tube's lifespan."

Hence my previous statement. Guess I misunderstood.

 

[sreten]

Hi,

Whatever you do, do not use 2R series resistors, will turn bass to mush.

TBH which taps you use will probably not make much difference,
4 ohm will be cleaner, 8 ohm will go a touch louder before clipping.

/sreten.

 

[Hartono]

enjoy your 4 ohm tap !!!

 

[theskintman]

enjoy your 4 ohm tap !!!

I am, and it's bloody marvellous

Thanks guys.