Monitor 10B options for subs or replace entire system

canadianicon25

just add a sub. sub's are easy. just adjust the crossover point until it sounds right. with full range speakers the sub won't need to amplify 'higher' frequencies (120Hz+) like a sat. and sub combo. go with a polk. go with a velodyne. go with anything really because in your setup a sub is only going to amplify a narrow band. try getting a sub with both a LFE and speaker level inputs. try them both out and see which sounds best in your environment.

OldmanSRS

Impedance value varies with the frequency. Speaker impedance is usually rated as "nominal impedance" meaning it's kind of sorta around the stated value most of the time but not really. It usually spikes way up at the XO points and is lowest in the lower frequencies.

When using a sub, phasing is important so it does not cancel bass produced by the PR in the 10's. XO point is important so you get a smooth transition of the PR to the sub. Placement is important to prevent standing waves the can add or or subtract the bass at your listening position.

I bought an HSU VTF-3 some years ago. Very pleased with the HSU products. When used with the 10's and the CRS+'s, it makes a formidable 2ch setup.

Anthony Hinton

I agree with the add a sub crowd, any decent powered sub would make a world of difference.

cowtrimmer

westmassguy wrote: »

Your probem isn't the 10s per se or the size of your room. The receiver you're using is only rated for 8 and 6 ohms. The 10s are 4 ohm speakers. You're not supplying them with sufficient power especially if your musical tastes include heavy bass tracks.

Even though the specs of the monitor10 speakers state they are 8 Ohm speakers they are actually 4 ? The reason I ask is because I was thinking of buying a pair, but may have to rethink this based on not having enough to drive them now.

jeremymarcinko

That onkyo in your sig will be just fine.The monitor 10's are just as efficient as those 70's. More power usually sounds better but I used a onkyo705 with my 10's for a while. I eventually added a amp but the onkyo was definitely sufficient and nice warm sound.

cowtrimmer

I wasnt going to use the Onkyo but use an old Scott receiver I had and make more of a display-vintage looking system and park it next to an old Coronado 6 tube short wave radio my Grandmother had given to me years ago.

84shovelhead

Hi have a set of 10's I bought new in '80 and recently added a polk psw 1000 from a guy on here that sells them with a 500 watt bash amp.In my setup this sub blended in perfectly and can really hit if you want-thogh I am not intothe unatural thump that some may prefer.Amp is a mitsubishi dar15 150 wpc dual mono construction as is the pre-amp.room size 14x30 with a large opening on one side,9plus foot ceilings ceramic floor.am loving the sound from this old "crap" and the look I get fromm friends who hear it!Almost as much fun as ripping it up on a bike!

jimsvm

More questions about 10s . Would the efficiency of speaker change with the new cross overs? Second, would the resistance change.? Thanks,

westmassguy

jimsvm wrote: »

More questions about 10s . Would the efficiency of speaker change with the new cross overs? Second, would the resistance change.? Thanks,

No on both counts

StantonZ

cowtrimmer wrote: »

Even though the specs of the monitor10 speakers state they are 8 Ohm speakers they are actually 4 ? The reason I ask is because I was thinking of buying a pair, but may have to rethink this based on not having enough to drive them now.

I wouldn't tell someone NOT to get a pair of Polks just because of impedance concerns, because it may not be a problem for you depending on what kind and how loud you listen to your music. However, if you like your music REALLY loud, you may want to re-consider your source of amplification.

shawnszj

Hi guys, I've been doing a lot of reading on the forum but this is my first post.
In regards to impedance of the 10s I bought a pair and a pair of 7s and a pair of m20 based on the fact that the Polk site rated them as 8ohm. For some reason I decided to put my fluke meter on them and test for resistance. Result 4ohm for both 10s and 7s. And 8ohm for the m20. Now I have a problem my receiver Yamaha RX V1900 manual says I can only use 4ohm on fronts and either 6ohm or 8ohm anywhere. I wanted to use the 7s in zone 2 or as surrounds, and the m20 as surrounds. Question if I use the 7s I'm I going to damage my amp? I like my music loud.
Confused

jeremymarcinko

It will be just fine, don't drive them to a clipping situation, otherwise enjoy

canadianicon25

Result 4ohm for both 10s and 7s.

Were your measurements taken directly from the speaker or did you connect your multimeter to the terminals on the back. To measure the DC resistance of the speaker you need to connect directly to the back of the speaker driver itself.

Another thing to note is impedance is an AC measurement not DC. Typically the resistance measurement on a multimeter is DC and a meter will not measure AC impedance.

Impedance is calculated by the following:

Z=R+jX where r= DC resistance and X= capacitive reactance - inductive reactance. You may want to google these topics. It gets somewhat mathy and requires knowledge of complex numbers.

shawnszj

Were your measurements taken directly from the speaker or did you connect your multimeter to the terminals on the back. To measure the DC resistance of the speaker you need to connect directly to the back of the speaker driver itself.



I took the measurement at the main terminals. (Where it matters for the amp) the amp doesn't connect to each driver separately. I do and have done some really large car audio setups, multi amps, 1,2,4ohm setups. I understand that each speaker is 8ohm but the way they are run in series reduces impedance at main terminals to 4ohm. I don't care about the math. In car audio if I ran a 2ohm load on a 4ohm amp, damage could and would happen. I'm just not sure about the effects of home audio (AC) hmmm impedance is AC I find that interesting think I will Google that.
Thanks

F1nut

I understand that each speaker is 8ohm but the way they are run in series reduces impedance at main terminals to 4ohm.

That is wrong. The only thing you are measuring is the resistance, not the impedance, which is variable anyway.

canadianicon25

yes! impedance fluctuates with frequency.

shawnszj

Ok I've done some googling. Now that i see it does fluctuate what do I set my amp to 4,6 or 8ohms I'm thinking 8ohm b/c the speakers are rated 8ohm nominal. Is this a correct assumption. Car audio is so much easier. Geeez





Resistors are "passive" devices, that is they do not produce or consume any electrical energy, but convert electrical energy into heat. In DC circuits the linear ratio of voltage to current in a resistor is called its resistance. However, in AC circuits this ratio of voltage to current depends upon the frequency and phase difference or phase angle ( φ ) of the supply. So when using resistors in AC circuits the term Impedance, symbol Z is the generally used and we can say that DC resistance = AC impedance, R = Z.

So DC resistance = AC impedance

canadianicon25

So DC resistance = AC impedance

Only in name. Both are acting against current flow. As you can see by the math the way in which they act against current flow is quite different.

an AC circuit has a combination or AC and DC. The DC component is said to be acting at 0 Hz. This is why the number for impedance is complex. Z=R+jX

The real part of the number, R, is the DC resistance. The imaginary part of the number, jX, is the value of the reactance which is depended on the capacitance and inductance of the circuit.

F1nut

Now that i see it does fluctuate what do I set my amp to 4,6 or 8ohms I'm thinking 8ohm b/c the speakers are rated 8ohm nominal. Is this a correct assumption.

Yes.