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Jerry G.
 
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Default Adding pair of loudspeakers to B system (newbie question)

If you add a second set of speakers and they are 8 ohms, and connected in
parallel, the impedance will be 4 ohms to the amplifier. This is going to
make the output stage run very hot, if the amplifier is not rated for 4
ohms. We see many amplifiers damaged from users adding on extra speakers
like this.

You can put them in series, but you will loose a lot of efficiency, and also
loose a lot of the damping factor.

What you really need is an amplifier that is rated to take a 4 ohm speaker
load for its operation. This will do the job for you.

--

Greetings,

Jerry Greenberg GLG Technologies GLG
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WebPage http://www.zoom-one.com
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"Henrik Johannisson" henrik[.]johannisson[@]telia[.]com wrote in message
...
Hi all!

I'm a owner of a Pioneer VSX-609RDS receiver and on the front speaker
system A
I have a pair of Pioneer S-H510V speakers (8 ohm, 90 dB/W).

Now I want to connect one more pair of speakers. These will then be
connected to
fron speaker system B. My purpose is to have both system A and B activated
at the
same time i.e. I want to hear sound from both A and B at the same time.

If I had understood everything correctly, the speaker pair A and speaker
pair B shall
have the same rating on BOTH impedance and sensivity in order for them to
sound
equally "loud".
But my big question is what ohm ratings the speakers must have in order to
avoid
overload the amplifier. Unfortunately the manual isnt good help : "Please
use
speakers rated between 8 ohm - 16 ohm".

What does that means? If only using system A it is obvious, the speakers
must be rated
between 8 and 16 ohm. But if I add another speaker pair on the system B? I
mean,
shall I see the speaker system A and B in serial or in parallel?!?! I think
I have seen
in some NAD manual that A and B seems to be in parallel.

Example 1:
Assume both A and B speakers are rated as 8 ohm. If A and B is in serial,
the total
will be 8+8=16 and it is within the range.

Example 2:
Assume both A and B speakers are rated as 8 ohm. If A and B is in parallel,
the total
will be 1 / (1/8+1/8) = 4 ohm and we are out of range!

So what should my ohm ratings be!?!?

Please help me!

/Henrik