Infinity RS152 Review (Surround Speaker)

[MZKM]

Athena made something "Similar" to this, way back in the 90s. I owned them and they were quite decent for the price. Wonder how they would compare to the units under review?View attachment 124554

That looks like one of your traditional bipole surrounds (they either are dual tweeter and dual woofer or single woofer and dual tweeter).

Monitor Audio still makes those kind as well as other companies:

Klipsch used to have these kind but now they are dual tweeter and dual woofer:

This Infinity is slightly different in that the woofer is on the rear. The difference would be that at the crossover frequency the interaction between them is with reflected sound and not direct.

I would very much like to see the measurements of a 2 woofer 2 tweeter bipole and a 1 woofer 2 tweeter bipole.

The SVS Ultra surrounds can switch from bipole, dipole, and 2ch (use dual binding posts where 1 pair is for side surround wiring and other pair is for rear surround wiring).

 

[MZKM]

My surrounds have terribly poor placement, where for 1 of them the couch is nearly under the speaker which is mounted about 6ft up, so vertical off-axis is hugely important.

Not sure if I should make a new thread for when I do measurements, but just so everyone sees what I am working with:

So yeah, had to made do with what I was given:

1) Original owner had surrounds wired pretty high and also is not centered with where the tv is. No I can’t center the setup on them as there is a staircase where the tv would go, here is an old photo (tv has been updated & have different speakers, no I was not running both pairs):

2) Surrounds had to be non-intrusive, so could not bring them lower as then the plate would be visible (and any wiring conduit I would use) and no arm mounts to swivel a bookshelf, which is why I went bipole as the 45° firing would help a lot for that corner speaker.

FYI: I took that photo of the George Washington bridge, quite proud of it.

 

[Robbo99999]

Has this already been said, I think this speaker would have to be measured in actual farfield rather than how the Klippel does it.....or at least with the actual microphone further away than the current system.....just an intuition! I'm aware that Klippel measures close and then will predict the output at a greater listening distance, but I think this speaker is just "too far off traditional design" to measure that close for accurate predictions.

 

[Vladimir Filevski]

Has this already been said, I think this speaker would have to be measured in actual farfield rather than how the Klippel does it...

No, Klippel NFS nearfield measurements and farfield computations are just fine, the problem is that some loudspeakers are designed to be mounted on the wall (or in the wall). There is no computation substitution for a real wall.
Klippel NFS has module with bafle for half-space measuring in-wall loudspeakers, and maybe it can be modified for measuring on-wall loudspeakers.
Khm, donors, khm...?

 

[Newman]

A weird speaker but I think it also shows your Klippel analysis machine makes certain assumptions about how speakers are used that doesn't apply to every speaker out there.

Incorrect. It shows how weird the speaker is, and how poor it is at creating a wide smooth frequency response in the listeners’ ears, or at creating tonally consistent reflections from room walls.

As with the test of the Magneplanar LRS, the method works for box type speakers but falls down when trying to measure dipole, cardioid, or surround speakers like this one that depends on sound reflected off of a wall.

Incorrect. Just like with the Magnepan (not ”Magneplanar”) LRS, the Klippel NFS works for any sound source of any configuration. It doesn’t even have to be a loudspeaker. It could be an acoustic pretzel, or a perfect omni, or acoustic laser beam, or anything in between.

I'm not saying that this is a good speaker- although it may work fine as a surround speaker to provide the whiz-bang gimmickry common in Hollywood / Disney productions these days.

What in fact you are measuring is how closely the speaker's performance matches the assumptions of the test.

There are no assumptions of the sort you mean, because the test is designed not to assume anything about the configuration or disperson of the DUT (device under test).

There's an inbuilt bias in the experimental design. I think for these tests to actually fit the definition of science, you'd need to limit testing to forward-firing box speakers that attempt to emulate a point source. Which is to say most speakers on the market.

From the Klippel website: “The Klippel Near Field Scanner is a measurement system, to measure the radiation characteristic of all sorts of sound sources”.

Oh my goodness. I just realised you would have written your comment without reading or learning about the Klippel at all. Why would you do that? Hopefully it is not some sort of simmering resentment about the poor performance of the Magnepan. Please tell me you don‘t use planar dipole speakers, and hence have a need to discount the Klippel as a narrow-purpose machine.

And it makes sense that Klippel developed their protocol to measure such speakers, because they are mostly what people buy and use.

Since your comment expresses such wrong views about the Klippel NFS, and got so many Likes, 16 to date, I thought I had better knock it on the head. You are the one who made “assumptions of the test”, not Klippel.

Cheers

 

[AverageJoeAudiophile]

Incorrect. It shows how weird the speaker is, and how poor it is at creating a wide smooth frequency response in the listeners’ ears, or at creating tonally consistent reflections from room walls.

Incorrect. Just like with the Magnepan (not ”Magneplanar”) LRS, the Klippel NFS works for any sound source of any configuration. It doesn’t even have to be a loudspeaker. It could be an acoustic pretzel, or a perfect omni, or acoustic laser beam, or anything in between.

There are no assumptions of the sort you mean, because the test is designed not to assume anything about the configuration or disperson of the DUT (device under test).

From the Klippel website: “The Klippel Near Field Scanner is a measurement system, to measure the radiation characteristic of all sorts of sound sources”.

Oh my goodness. I just realised you would have written your comment without reading or learning about the Klippel at all. Why would you do that? Hopefully it is not some sort of simmering resentment about the poor performance of the Magnepan. Please tell me you don‘t use planar dipole speakers, and hence have a need to discount the Klippel as a narrow-purpose machine.


Since your comment expresses such wrong views about the Klippel NFS, and got so many Likes, 16 to date, I thought I had better knock it on the head. You are the one who made “assumptions of the test”, not Klippel.

Cheers

You're literally missing the point.

This speaker is not intended or designed to be listened to in anyway which would not include wall mounting.

As such. Any measurements event in which the speaker is not wall mounted will not give an accurate assessment of the design goals and end user performance.

The Kippel system may have measured the speaks accurate in free air. But not in a way that would accurately reflect it's implementation .

 

[Chromatischism]

Quote "With the HST design, a rear-facing woofer is scientifically positioned at a given distance from the wall "

So unless your room replicates theirs, all the alleged qualities are lost?

The speaker mounts ON the wall with the built-in bracket, so everyone's results will be the same.

This goes to show the Klippel can't figure out a speaker design like this, and it is not designed to run anechoically. I can vouch for them and say that they don't sound like these measurements. The high frequency range, yes. But the mids and lows, not quite.

 

[Chromatischism]

I have not listened to the speaker as I don't have a setup to test surround speakers in my 2-channel system.

I tested them by just setting it up like any other speaker. Just connect it to front left or front right. Make sure to push it back against the wall.

The sound is indeed more diffuse. Larger. You won't get pinpoint imaging. It's pretty much what they describe.

 

[Francis Vaughan]

Since your comment expresses such wrong views about the Klippel NFS, and got so many Likes, 16 to date, I thought I had better knock it on the head. You are the one who made “assumptions of the test”, not Klippel.

Seriously, did you not read the rest of the thread? You have it totally wrong, and just about everything you claimed as incorrect is in fact correct. You would do well to take the time to understand just what the Klippel system is, how it works and what its limitations are. It is not a perfect system, there are specific limitations about how it works and in particular the assumptions the system makes in projecting the measured field into the room are limiting. Sadly it does not model the expansion of the hologrpahic field it measures into the room, it just makes some very basic calculations of rough aggregate values off the walls. It just expands the calculated polars into the room and applies some simple weightings. It does not model phase, and basically models the speaker in the room as monopole. Thus is only valid for a conventional box speaker in free space in the room. It gets in-room respose of panels and other di-pole speakers wrong in-room because of this.
A speaker that requires the loading of a wall and is intended to utilise that wall as part of the radiating system, one designed to radiate into a half space, is not modelled by Klippel's software. The RS152 measured here is designed to include a wall as an intrinsic part of the speaker's operation. Klippel's software has no way of understanding this, there is no mechanism for even telling it that there should be a wall. Without a wall, the measurements, whilst interesting do not, and cannot, reflect actual intended use case operation.

 

[Newman]

Wow, some really ill-informed postings about the Klippel here.

Of course it doesn’t model the room response: but now you have to show me where I said it does. Good luck.

But it does model near and far fields, in free space.

And doing so is not a failing, just because the speaker is meant for wall placement. Like Toole says, the direct-arrival sound from the speaker needs to have a FR that is level, smooth, and extended. And the ear will separate it and respond to it independently of room reflection contributions, so the summmed room response of a speaker cannot be argued to compensate for failings in the first-arrival sound. It’s a litmus test for all speakers. The Klippel will tell us this for any speaker of any design. It’s valuable information.

Also, Klippel provides a way to measure in-wall speakers with NFS, so don’t tell us “Klippel is not meant for it”. Whether Amir used it is another matter, but don’t brush off the Klippel as unsuited to that task.

Also, @AverageJoeAudiophile I didn’t miss the point, because the point was made wrt this speaker and the LRS, both. We know the LRS is not intended for wall mounting, so the point being made was that Klippel is only suited to front-firing monopoles. That was the point that was made, in exact words, “you'd need to limit testing to forward-firing box speakers that attempt to emulate a point source”, so maybe you missed it?

cheers

 

[amirm]

This goes to show the Klippel can't figure out a speaker design like this, and it is not designed to run anechoically.

This is an odd comment. No speaker measured anechoically shows the response when place in any room. Room modes alone destroy the frequency response below a few hundred hertz.

The purpose of anechoic measurements is to give you room independent measurements so that you know exactly that the speaker is radiating. This give you true insight on how the speaker operates in a way that no in-room measurement shows you. Things like driver resonances, how they are mixing in treble, etc. are all highly revealing in the NFS measurements.

It is not the job of NFS to figure anything out with respect to room interactions beyond what CEA-2034 specifies. Anything more than that is left to the person analyzing the results.

 

[Chromatischism]

Right, I understand that. But we see a speaker design here that relies on the wall boundary to operate as intended.

 

[amirm]

Right, I understand that. But we see a speaker design here that relies on the wall boundary to operate as intended.

Only in a certain frequency range that the woofer operates in. Above that what you see is what you get with NFS.

 

[Francis Vaughan]

Only in a certain frequency range that the woofer operates in. Above that what you see is what you get with NFS.

Yes, but rather than say “certain frequencies” how about some numbers. I’m going to nominate the crossover frequency as the upper end.
The bass driver response in the very low range is omnidirectional but that does not take into account the acoustic impedance of the small gap to the wall loading the system. That will change the alignment of the low bass significantly. Nor is the half space gain taken into account. So my lower bound is the bass cutoff.

 

[don'ttrustauthority]

I would test these with a system in mind, and therefore these could be expected to have a 1 kHz dip because a lot of speakers working together will color the response in a way that it's unfair to measure alone.

I mean, it tells us nothing.

 

[richard12511]

Agree completely with Amir's mailman panther. Measurements look horrible by normal monopole free-space box speaker standards, but it's also clear that these have a completely different target(and purpose) in mind. Not sure what conclusions can really be drawn, if any at all.

Would be interested to see what the spin looks like mounted to a really large board. Would the NFS support that?

 

[Chromatischism]

I'll throw in my 2 cents, for science

I just set up one against the wall and did a moving mic average to see how the response looks in-room. The average was about 10-15 seconds long over the listening area (my recliner).

Pink periodic noise, full range.

No smoothing

About the room:

• Everything under 33 Hz is room gain
• 60-90 Hz is boosted by room modes (constructive)
• 120 and 180 Hz also get wrecked by said room modes (destructive)
• The pattern repeats through the 200-300 Hz range
• Basically, ignore that range, we cannot see results there unaltered by my room

What I see is that the drivers sum nicely in a smooth response down to the room transition frequency range below around 350 Hz here where the room starts to interfere with the long wavelengths. I am not seeing the massive suckout centered on 600-700 Hz as measured by the Klippel.

What can we conclude from this?

Edit: another screen shot scaled closer to Amir's posted below.

 

[Sancus]

Yes, but rather than say “certain frequencies” how about some numbers. I’m going to nominate the crossover frequency as the upper end.

I mean we've seen in-room measurements and we see it has issues below the crossover frequency as well, in fact it has issues as low as 600hz. Others have pointed out as early as page 1 that this approach doesn't work well past low frequencies. I'm not sure why people are still arguing that this speaker's going to have a good response as long as you put a wall behind it, when it clearly doesn't. That said I think it's totally fine as a very low cost($70/ea?!) surround when on sale. But if you are looking for objectively good surrounds you should look elsewhere.

 

[dmac6419]

Think I'll order a set when they go on sale,people who actually own them give em rave reviews

 

[MZKM]

Agree completely with Amir's mailman panther. Measurements look horrible by normal monopole free-space box speaker standards, but it's also clear that these have a completely different target(and purpose) in mind. Not sure what conclusions can really be drawn, if any at all.

Would be interested to see what the spin looks like mounted to a really large board. Would the NFS support that?

The NFS sells a baffle for driver & in-wall speakers and I believe it only does measurements on the front hemisphere, so no Spin, but you would get +/-90° horizontal and +/-9° vertical off-axis measurements:

I don’t believe Klippel has on-wall testing, though it shouldn’t be much different.