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RP-240S Surrounds Always Calibrate to 150 HZ Crossover by Audyssey


Kris

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My RP-240S surrounds, whether placed as side-surrounds or back-surrounds, always end up with 150 Hz crossover when calibrated by Audyssey MultEQ or MultEQ XT32. The Klipsch datasheet for the RP-240S states 62-25kHz +/- 3dB, so I would expect these should calibrate to 80 Hz crossover without issue. Anyone have similar issue ? Anyone have actual frequency response test data for these speakers ?
 

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2 hours ago, Kris said:

My RP-240S surrounds, whether placed as side-surrounds or back-surrounds, always end up with 150 Hz crossover when calibrated by Audyssey MultEQ or MultEQ XT32. The Klipsch datasheet for the RP-240S states 62-25kHz +/- 3dB, so I would expect these should calibrate to 80 Hz crossover without issue. Anyone have similar issue ? Anyone have actual frequency response test data for these speakers ?
 

 

Welcome to the forum!

 

Are the surrounds placed to take advantage of boundary gain?  Klipsch's figures may be based on the availability of boundary gain in the bass.   I doubt if 4" woofers would be good to 62 Hz (or 80 Hz) in an anechoic chamber (unless pressed into the

non-anechoic corner of the Klipsch "revolving door" chamber). image.png.d2f6ac5dc8efb1902b0bb46d86a9240f.png

 

In the manual for the RP-240S, we find, "... The surrounds should be placed on the walls directly adjacent to the listening position. Another option would be on the wall behind the listening position. The final surround speaker placement depends on your room’s characteristics ..."

 

There are several cases on the AVS "Official Audyssey thread part II" in which a surround very near a wall or in a corner will be assigned a crossover of around 80 Hz, whereas another surround of the same make and model, but not near a wall, will get a crossover much nearer 150 Hz.  IIRC, this was most often true in "Open Plan" rooms with no wall support nearby on one side.

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On 9/4/2019 at 11:04 PM, garyrc said:

Are the surrounds placed to take advantage of boundary gain?  Klipsch's figures may be based on the availability of boundary gain in the bass.   I doubt if 4" woofers would be good to 62 Hz (or 80 Hz) in an anechoic chamber (unless pressed into the

non-anechoic corner of the Klipsch "revolving door" chamber). 

 

In the manual for the RP-240S, we find, "... The surrounds should be placed on the walls directly adjacent to the listening position. Another option would be on the wall behind the listening position. The final surround speaker placement depends on your room’s characteristics ..."

 

There are several cases on the AVS "Official Audyssey thread part II" in which a surround very near a wall or in a corner will be assigned a crossover of around 80 Hz, whereas another surround of the same make and model, but not near a wall, will get a crossover much nearer 150 Hz.  IIRC, this was most often true in "Open Plan" rooms with no wall support nearby on one side.

 

At the time of Calibration, one surround was within 3.5-inches of wall and other surround was 3-feet from wall, due to room layout constraints. I will run some Audyssey calibrations on weekend with the two RP-240S' placed on test wall and various distances from wall. 

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On 9/6/2019 at 6:31 PM, wuzzzer said:

Audyssey very commonly comes up with random crossover points.  Just run it then change everything to 80Hz.

 

IMO, it's not really random in a technical sense ... more like the opposite of random, i.e. systematic, but unexpected, because of not knowing the details of the systematic influences, including, but not limited to, different boundary gain and extension for different locations in the room. 

 

I don't know about "very commonly;" Audyssey has always been fairly well behaved at our house, but, in our room, with our boundary gain, our surrounds have an F3 below 80 Hz (approx. 60 Hz).  Our front speakers, with their boundary gain, have a 3 dB down point of well below 40 Hz; so the pre-pro was engineered by the pre-pro manufacturer (not Audyssey) to take the F3 assessment from Audyssey and somehow interpret it as calling for a setting of "Large" and a x-over of 40 Hz, as if to say, as Kal Rubinson quipped in the Stereophile review, "Congratulations, Sir," on buying such a bass capable speaker.  Chris K, of Audyssey criticized this manufacturer view, and feels,  as does nearly everyone, that 80 Hz is the proper crossover for speakers that have an F3 measured (by Audyssey), with whatever boundary gain to which they are subject, to be well below 80 Hz.  The danger (danger of distortion and, with inexpensive, delicate, surrounds, danger of overload in the bass at high SPL) comes when the speakers, in their position in the room, are set for, say, 80Hz when the functional crossover for those speakers, in that location, is really 110 Hz.  Thus the rule, you may raise the crossover above the F3, but not lower it."

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Audyssee measures my RP-240's at 80Hz - sometimes 90Hz - the speakers are mounted in the middle of a long wall so no boundary gains to be expected.

 

I would suggest to put your amplifier in all-channels mode (or connect the RP-240's temporarily as main speakers) and play music loud for a while to loosen the woofers as I remember that my speakers measured higher than 80Hz in the beginning as well.

 

It is not a good idea to lower the cross-over frequency manually because Audyssee does not provide correction below the auto-measured value (setting the cross-over frequency manually higher is not problematic).

 

 

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Here are the results of additional Audyssey MultiEQ XT32 calibrations of the RP-240S as surrounds. For all calibrations below, surround left enclosure back is 52.0 inches from wall and surround right enclosure back is 3.5 inches from wall. 

 

1. RP-240S with drivers at +/- 45 degrees to Audyssey microphone (normal wide dispersion usage). Audyssey set crossover to 120 Hz:

 

RP-240S-SURROUND-LEFT-45-DEGREES.thumb.jpg.35986f427da499d5c02e2f6ad33e017a.jpg

 

SRP-240S-SURROUND-RIGHT-45-DEGREES.thumb.jpg.a88750f785c56544adffcaae3b12a710.jpg

 

2. Both RP-240S rotated so that one set of drivers are 0 degrees to Audyssey microphone (i.e. on axis). Audyssey set crossover to 110 Hz:

 

RP-240S-SURROUND-LEFT-0-DEGREES.thumb.jpg.49698d8b7c03f54ac55ece86d13cbd4d.jpg

 

 

RP-240S-SURROUND-RIGHT-0-DEGREES.thumb.jpg.dd894ad9a637fe8ce740a97505264d24.jpg

 

 

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6 hours ago, JefDC said:

Audyssee measures my RP-240's at 80Hz - sometimes 90Hz - the speakers are mounted in the middle of a long wall so no boundary gains to be expected.

 

I would suggest to put your amplifier in all-channels mode (or connect the RP-240's temporarily as main speakers) and play music loud for a while to loosen the woofers as I remember that my speakers measured higher than 80Hz in the beginning as well.

 

It is not a good idea to lower the cross-over frequency manually because Audyssee does not provide correction below the auto-measured value (setting the cross-over frequency manually higher is not problematic).

 

 

 

Yes I will run proper white noise and pink noise break-in on these speakers and then re-run Audyssey calibrations.   

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Kris,

my speakers are mounted flush against the wall (both speakers).

So I do have a certain boundary gain but not a corner boundary gain.

 

I read now that your speakers are positioned a certain distance from the wall, which might be the reason of the higher cross-over and in line with the info in the first reply from garyrc 

 

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1. After a week of pink noise, brown noise, and music break-in (3-4 hours per day), I re-calibrated using Audyssey. Speakers were placed in same location/orientation as previous direct/0-degree position vs Audyssey microphone. The speakers calibrated to the same 110Hz crossover. Plots attached at end. 

 

2. It is interesting that that the previous generation RS-42II surrounds speakers have the identical frequency specs yet the RS-42 II was a ported speaker. When I was shopping for surrounds, the store had both RP-240S and RS-42II's in their setup room so I was able to compare both at the same time. The RS-42II had an obviously audible lower frequency range. I ended up buying the RP-240S since the RP-240S specs of 62Hz implied an 80Hz crossover should be easily attainable and all my other speakers were RP line. Specs:

 

RP-240S:

FREQUENCY RESPONSE: 62-25kHz +/- 3dB

SENSITIVITY: 93dB @ 2.83V / 1m

POWER HANDLING (CONT/PEAK): 75W/300W

CROSSOVER FREQUENCY: 1500Hz

HIGH FREQUENCY DRIVER: Dual 1" Titanium LTS Tweeters with Hybrid Tractrix Horns

LOW FREQUENCY DRIVER: Dual 4" Cerametallic Cone Woofers

ENCLOSURE TYPE: Sealed

HEIGHT 11.61” (29.5 cm)

WIDTH 10.38” (26.4 cm)

DEPTH 6.93” (17.6 cm)

WEIGHT 13.2 lb (5.99 kg)

 

RS-42II:

Frequency Response: 62Hz-24KHz ± 3dB

Sensitivity: 93dB @ 2.83V / 1m

Power Handling: 75W RMS / 300W Peak

High Frequency Crossover: 1700Hz

High Frequency Drivers: Dual 1” (2.54cm) Titanium diaphragm compression drivers mated to 90° x 60° square Tractrix® Horns

Low Frequency Drivers: Dual 4” (10.2cm) Cerametallic™ cone woofers

Enclosure Type: Bass-reflex via dual side-firing ports

Height 10” (25.4cm)

Width 12.5” (31.7cm)

Depth 7.1” (18cm)

Weight 11.9lbs (5.4kg)

 

3. Sound & Vision's measurements of the larger RP-250S showed –6dB point is at 90 Hz, so how the smaller RP-240S could ever reach 62 Hz +/- 3dB is puzzling.

 

"The RP-250S’s three-face averaged response measures +4.46/–3.36 dB from 200 Hz to 10 kHz. The –3-dB point is at 106 Hz, and the –6-dB point is at 90 Hz. Impedance reaches a minimum of 3.98 ohms at 218 Hz and a phase angle of –51.81° at 120 Hz."

 

https://www.soundandvision.com/content/klipsch-reference-premiere-rp-150m-speaker-system-review-test-bench

 

4. I need to clear some space to do an on wide-wall and corner-wall test/calibration although based on all data so far I highly doubt these speakers are capable of +/-3 dB at 62 Hz in any situation. If Klipsch has any data they can provide to prove the performance of these speakers in a variety of topologies, I would need to see that to believe these are correct frequency specs.

 

5. Audyssey results for item 1 (after speaker break-in):

 

Screenshot_20190914-122937_MultEQ.thumb.jpg.e72c7c5aa5ac5cd599362e5cc7d63450.jpg

 

 

Screenshot_20190914-122944_MultEQ.thumb.jpg.713e5fd7d5956d3ab02e0334eb96c4ac.jpg

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8 hours ago, Kris said:

"...The –3-dB point is at 106 Hz..." Sight and Sound

 

An F3 (-3dB point) of 106 Hz would call for a 110 Hz crossover, or higherSound and Vision measured in a quasi-anechoic environment, but Klipsch says the speakers should be on a wall, where the F3 might be a bit lower in frequency.  I would guess that Klipsch would have measured a speaker meant for wall mounting on the wall of their special anechoic chamber a few feet away from the corner, but hung right against the wood.image.png.993a23aa6407c60445606e7339e1558e.png   If it actually did turn out to be lower in frequency Audyssey would feel free to recommend to the AVR/AVP turning the bass up, until flatish response at the F3 is reached, if possible (Audyssey can recommend up to a 9 dB boost or down to 20 dB cut at any of the hundreds of points at which it measures).  Below the measured F3 Audysssy has a "hands off" policy.  The final decision on x-over is up to the AVR/AVP, not Audyssey, even though it is based on data Audyssey collects..  Audyssey first determines the -3dB down point of your surround, in your room, where your speakers happen to be in the room, then recommends a crossover to your AVR or AVP, which is probably a bit higher.

 

Years ago (1950s), JBL refused to publish frequency specifications and sensitivity measurements; instead they pointed out that there were no standards.  Later AES came up with standards, but they didn't hold very well for rooms in the home.  Neither do quasi-anechoic measurements of the overall frequency response, or the F3, as the differences between Stereophile's in-lab and in-room measurements indicate (we won't even speak of their "in-driveway on a furniture dolly" measurements).  Neither does a measurement in your listening room at a single point, because moving the microphone a few inches can change the results significantly.  That's one reason Audyssey uses 8 microphone positions and their proprietary fuzzy averaging device that is intended to be better than an arithmetical average.

 

About the same time (?) Paul Klipsch was asked what a speaker's power handling capacity meant, exactly.  I believe I remember his response being, "Probably not a lot."

 

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