Dumb question of the day

tonyr1

I'm a newbie at this so don't flame me too badly. lol I've had a pair of monitor 10b's since new. I always thought they were 4 ohm speakers, but I think I read somewhere they were 8 ohm......I'm confused:o
can someone straighten me out on this?

gdb

I can't tell you the answer but, I CAN add to your confusion by telling you that some Polks are 6ohms also !! :eek: With the flaky record keeping and mid-run changes that were made, I'd say if you want to be absolutely sure about the impedance, you should have someone test them with a multimeter.;)

greg2350

Driver Complement
Subwoofer 1 - 10" Diameter (25.40cm)
sub bass radiator
Midrange 2 - 6-1/2" Diameter (16.51cm)
drivers
Tweeter 1 - 1" Diameter (2.54cm)
Polk SL2500
Electrical
Overall Frequency Response 25Hz - 25kHz
Lower -3dB Limit 37Hz
Upper -3dB Limit 25kHz
Nominal Impedance 8 ohms
Recommended Amplifier Power 20-250 w/channel
Efficiency 89 dB
Dimensions
Cabinet Size 28" H x 15" W x 12" D
(71.12cm H x 38.10cm W x 30.48cm D)
Shipping/Other
Total Shipping Weight 46.00 lbs. (20.87kgs)

comfortablycurt

greg2350 wrote: »

Driver Complement
Subwoofer 1 - 10" Diameter (25.40cm)
sub bass radiator
Midrange 2 - 6-1/2" Diameter (16.51cm)
drivers
Tweeter 1 - 1" Diameter (2.54cm)
Polk SL2500
Electrical
Overall Frequency Response 25Hz - 25kHz
Lower -3dB Limit 37Hz
Upper -3dB Limit 25kHz
Nominal Impedance 8 ohms
Recommended Amplifier Power 20-250 w/channel
Efficiency 89 dB
Dimensions
Cabinet Size 28" H x 15" W x 12" D
(71.12cm H x 38.10cm W x 30.48cm D)
Shipping/Other
Total Shipping Weight 46.00 lbs. (20.87kgs)

Those are the specs for the Monitor 10 Series II. He has a pair of Monitor 10B's...slightly different speaker.

Generally speaking, the Monitors are usually about 6 ohm nominal.

zingo

What are you powering them with? The impedance shouldn't matter too much as long as your amp is stable and not clipping. Welcome and enjoy.

bluecomet

Run an amp that can handle 4 ohms stable and then don't worry about a thing. If you have a Monitor A or B I believe they are 6 ohms. I am not sure about Monitor C's. Do you know which Monitors you have. If there is a fuse on the back they are older models.

tonyr1

zingo wrote: »

What are you powering them with? The impedance shouldn't matter too much as long as your amp is stable and not clipping. Welcome and enjoy.

when I bought them I bought a Harman Kardon pm665 , had problems with them cutting out when too loud. then I had a Yamaha HT amp, can't remember the model, same problem. then I bought a JVC RX DP15 7.1 . same problem. now I have bought an Adcom 555 on ebay....maybe that will finally be the one that will power these things without problems. might look into using the HK 665 for a pre-amp until I can get an Adcom 715 or 750.

tonyr1

bluecomet wrote: »

Run an amp that can handle 4 ohms stable and then don't worry about a thing. If you have a Monitor A or B I believe they are 6 ohms. I am not sure about Monitor C's. Do you know which Monitors you have. If there is a fuse on the back they are older models.

I believe they are b's. I had a pair with fuses for a couple of years until they were stolen. these ones were the replacements. no fuses. I have an Adcom 555 on the way, should do the job.

hearingimpared

gdb wrote: »

I can't tell you the answer but, I CAN add to your confusion by telling you that some Polks are 6ohms also !! :eek: With the flaky record keeping and mid-run changes that were made, I'd say if you want to be absolutely sure about the impedance, you should have someone test them with a multimeter.;)

I believe the impedance rating on a speaker is based on reactance thus rendering a multimeter useless. Someone please correct me if I'm wrong.

comfortablycurt

That Adcom 555 will do a wonderful job of powering them. I've got my Adcom 545 running my Monitor 7A's(6 ohm nominal) right now, and it sounds fantastic. It can drive them to levels louder than I ever care to listen to.

That 555 is VERY stable at low impedances.