What was SVS thinking?

[GranteedEV]

Maybe not the most reactive load, but check the impedance

http://www.svsound.com/products/speakers/mts_family/MTS-02_Specs_Binder.pdf

I mean i commend them for posting the graph, but how the hell do you call that a 4 ohm load? IT doesn't even reach 4 ohms until the upper treble!

 

[funky waves]

Seen worse, seems to average close to 3ohm, about the lowest I would consider a 4ohm nominal. Any decent amp should be just fine.

 

[GranteedEV]

Seen worse, seems to average close to 3ohm, about the lowest I would consider a 4ohm nominal. Any decent amp should be just fine.

What would you consider a decent amp? AT ~$1400/pr, you're not going to spend more on electronics than your speakers. around %50-60 is what I would think one would spend, and that usually doesn't include separate amps. You're probably looking at a demographic that spends somewhere from 500-700 on a receiver. Something like a Marantz SR5005 perhaps... Do you think most 100wpc receivers in this range don't mind?

 

[funky waves]

I would consider most recievers over ~500-600 to usually be decent, if they are rated for 4ohm load they should be fine. I wouldnt use a ~200 reciever on them, most probably wouldnt like that load.

 

[ParadigmDawg]

Kind of like my 100's being called 8ohm but they dip deep into the 3's...

 

[TLS Guy]

What would you consider a decent amp? AT ~$1400/pr, you're not going to spend more on electronics than your speakers. around %50-60 is what I would think one would spend, and that usually doesn't include separate amps. You're probably looking at a demographic that spends somewhere from 500-700 on a receiver. Something like a Marantz SR5005 perhaps... Do you think most 100wpc receivers in this range don't mind?

That is the sort of spec sheet every manufacturer should publish. I think it is very typical for a good 2.5 way.

Face it receivers can't properly drive decent speakers.

When you allow for the phase angles the amplifier will see an impedance lower than the curve. For instance at 85 ohms the impedance is 2.5 ohms however because of the phase angle the amplifier will actually see a 2 ohm load.

While a receiver may not self destruct, it won't deliver its rated power by quite a margin.

Don't be hard on SVS. They have let it all hang out. This set of measurements is quite typical, and I bet there are worse out there no one knows about.

If you want good speakers, and yes there is a relationship to impedance drop and the quality of step loss compensation, then plan on putting an external amp in the budget.

This spec. sheet is just an illustration of what I have been trying to tell you for years.

 

[GranteedEV]

So how exactly are you supposed to read electrical phase angles anyways?

If you say that it's necessary for a good speaker, i do believe you, but then how does, say, revel pull off a 4-way flagship speaker that has no dips below ~3.7 ohms?

 

[mike c]

a pro amp in the 500-600 dollar range would have ABSOLUTELY no problem running these speakers to ear damaging volumes.

 

[TLS Guy]

So how exactly are you supposed to read electrical phase angles anyways?

If you say that it's necessary for a good speaker, i do believe you, but then how does, say, revel pull off a 4-way flagship speaker that has no dips below ~3.7 ohms?

We have been down this road before. It is all about the power triangle.

They quote the phase angle between current and voltage at two frequencies: -

Phase (@85 / 4200 Hz) -16 / +25 degrees

The reason for just specifying those frequency points is not stated. It would be nice if they had shown a graph with current and voltage plotted against frequency.

However at 85 Hz there is a phase angle of -16 degrees. That tell us that the load is largely capacitative at that point whereas at 4200 Hz it is +25 and largely inductive.

Where impedance and phase come out is the luck of the draw. You basically design for a flat frequency response with minimum violence to time and phase and you take what you get.

I really hope we can move away from the passive crossover. These issues don't apply with active designs.

 

[GranteedEV]

They quote the phase angle between current and voltage at two frequencies: -

Phase (@85 / 4200 Hz) -16 / +25 degrees

The reason for just specifying those frequency points is not stated. It would be nice if they had shown a graph with current and voltage plotted against frequency.

thanks for the link. Anyways they did have a phase graph, it's the pale pink top portion of the impedance graph on page 3, isn't it? Or is that something else?

 

[3db]

We have been down this road before. It is all about the power triangle.

They quote the phase angle between current and voltage at two frequencies: -

Phase (@85 / 4200 Hz) -16 / +25 degrees

The reason for just specifying those frequency points is not stated. It would be nice if they had shown a graph with current and voltage plotted against frequency.

However at 85 Hz there is a phase angle of -16 degrees. That tell us that the load is largely capacitative at that point whereas at 4200 Hz it is +25 and largely inductive.

Where impedance and phase come out is the luck of the draw. You basically design for a flat frequency response with minimum violence to time and phase and you take what you get.

I really hope we can move away from the passive crossover. These issues don't apply with active designs.

A phase angle of 16 degrees tells me that there is some capacitance but not largely capacitance. Speakerss aside and based on AC theorey...at 45 degrees, the impedance is half resistive and have capacitive or reactive so 16degrees tells me that the load is still more resistive than capacitive.

 

[MinusTheBear]

Maybe not the most reactive load, but check the impedance

http://www.svsound.com/products/speakers/mts_family/MTS-02_Specs_Binder.pdf

I mean i commend them for posting the graph, but how the hell do you call that a 4 ohm load? IT doesn't even reach 4 ohms until the upper treble!

As TLSGuy said they are forthcoming with the information so they deserve credit for that. With the majority of manufacturers you will be lucky to even get an impedance graph out of them. I have seen speakers that were rated at 8 ohm having impedance minimums below 3 ohms. Minimum dips below 4 ohms is very common.

 

[funky waves]

This I call 4ohm nominal. I believe all speakers should have impedance graphs published, or at least be available upon request. Kudos to SVS for publishing spec sheets with actual specs, so many times spec sheets have no real information at all.

 

[mtrycrafts]

...

Phase (@85 / 4200 Hz) -16 / +25 degrees

The reason for just specifying those frequency points is not stated. ....

The very first graph they provide has the phase angle plotted even thought the title does not specifically state it.
The two data point they state in the spec sheet are the two extreme shifts in phase, negative and positive. So, I would think that the phase is pretty good overall.