Looking to run a true 5HZ signal to my Sub woofers but think my anthem receiver will Bottle neck this.

[j_garcia]

Curious, just how much better picture quality did the later versions actually bring?

BD not so much, but the UHD definitely looks far better than it ever has. Seems it was rescanned from the original print and cleaned up.

The Atmos mix is better as well, except that they did not bring back the deep bass.

 

[m. zillch]

Thank you so much for sharing this. It does at least confirm that there is no hard cut at 15 hz, using ARC genisys, which is awesome.

I didn't watch the complete video, but by my read/analysis of the image at 18m09s showing before vs. after curves in this video,

not only does ARC genisys room correction (at least in this AM90) not work below ~15Hz, it also looks to have already applied a steep reduction in output by 15Hz as well.

This would not surprise me because I'd assume they know what they are doing and from my perspective reproducing ultrasonic and infrasonic content in audio not only is unproductive to what we hear, even with ultrasonic and infrasonic capable playback systems playing content containing ultrasonic and infrasonic sound, but it is detrimental to the sound quality of the important audible range content we do care about, for several reasons including the potential creation of intermodulation distortion. [Details and backing references upon request.]

Also to reiterate what I wrote earlier, for reliable results evaluating/measuring what electronics like ARC genisis do should ideally be done directly (electrically) not be done acoustically after additionally passing the signal through the modifications of power amps, loudspeakers/subs, room acoustics, varying mic selections/placements/aimings, in non-anechoic (non-soundproof) rooms potentially contaminated with background sounds which we may not be consciously aware of (because they may fall below our detection thresholds for those frequencies but not necessarily that of the test mic's).

 

[Allen Vos]

Here is the model of the driver under discussion.

I have done this very carefully. The program used was Bass Box Pro. This is a highly regarded program and used by many professional designers.

It basically shows what I had surmised from my now 72 years of speaker designing and building spekers.

First of all, it seems to be a very capable driver, but it can not perform miracles and has to abide by natures physical laws.

So the highlights.

Bass Box pro, as expected indicates this driver is suitable for sealed application only.

The optimal sealed volume is 8.28 cu.ft. with heavy fill.

The native F3 is as expected about an octave above Fs. which is 39.54 Hz, which rounding it off is 40 Hz, exactly what I estimated. So the driver rolls of at 12 db. per octave as all sealed designs do. Therefore it is -12 db. at 20 Hz as expected. So a boost of 12 db. per octave needs to be applies below 40 Hz.

Now this driver has good excursion limits, but it starts to head towards xmax below 20 Hz as you would expect. At 20 Hz the driver will tolerate 200 watts of power, below that it starts to exceed X-max, by 15 Hz the driver is running out of cone displacement and output is falling off and the driver risking damage. So as I suspected the driver needs high passing at 20 Hz, which is its effective lower frequency limit, as I suspected.

So, in essence this is a very capable sub driver, but it does not perform the miracle of defying the laws of physics. However with capable amplification and proper high and low pass filter settings, it appears to be a very capable LF driver, which for its cost and size it should be.

I hope this puts an end to the nonsense that has appeared on this thread and the insults from the OP. I stand by this model unreservedly, and it reveals the full facts of the situation.

I appreciate your feedback and experience, but I have a few questions about your findings as they differ significantly from my own modeling.

• Xmax Discrepancy: The manufacturer's website lists Xmax at 29mm, but your data shows 34mm. Could there be a typo in your parameters? One small key difference might be the enclosure volume. My net internal volume is 6.2 cubic feet (6.6 gross minus 0.4 for driver displacement and bracing), whereas your model utilizes an 8.2 cubic foot enclosure. This larger volume somewhat explains why your model shows higher excursion.

• Graph Scale Contradiction: Your cone excursion graph cuts off at 18mm, though it should scale to at least 29mm or 34mm based on your data. Because the graph stops there, it shows 18mm of excursion at 6 Hz, which directly contradicts your claim that the driver runs out of excursion at 15 Hz.

For comparison, I modeled this in WinISD with 1,200 watts of input power and triple-checked the data. My graph shows 19mm of excursion at 20 Hz and 10 Hz, peaking at 23mm at 5 Hz.
Additionally, the designer confirmed this sub can play down to DC (0 Hz). I have also personally verified four of these units playing down to 10 Hz via a calibrated microphone and SPL graph. Given these gaps, I respectfully disagree with your conclusions and would love to figure out why our models don't match.

 

[Allen Vos]

I didn't watch the complete video, but by my read/analysis of the image at 18m09s showing before vs. after curves in this video:

not only does ARC genisys (at least in this AM90) room correction not work below ~15Hz, it also looks to have already applied a steep reduction in output by 15Hz as well.

This would not surprise me because I'd assume they know what they are doing and from my perspective reproducing ultrasonic and infrasonic content in audio not only is unproductive to what we hear, even with ultrasonic and infrasonic capable playback systems playing content containing ultrasonic and infrasonic sound, but it is detrimental to the sound quality of the important audible range content we do care about, for several reasons including the potential creation of intermodulation distortion. [Details and backing references upon request.]

Also to reiterate what I wrote earlier, for reliable results evaluating/measuring what electronics like ARC genisis do should ideally be done directly (electrically) not be done acoustically after additionally passing the signal through the modifications of power amps, loudspeakers/subs, room acoustics, varying mic selections/placements/aimings, in non-anechoic (non-soundproof) rooms potentially contaminated with background sounds which we may not be consciously aware of (because they may fall below our detection thresholds for those frequencies but not necessarily that of the test mic's).

The one thing we all agree on is that ARC correction stops at 15 Hz. But I'm getting conflicting info on whether Anthem receivers will actually pass frequencies below 15 Hz when ARC is turned on. Some guys say yes, but others—including a tech from Anthem—say it cuts it off.
Everyone does seem to agree on one thing though: with ARC turned off, the receiver will pass a 5 Hz signal with no problem. Honestly, I'm just going to test it both ways myself once everything is hooked up.

 

[m. zillch]

Everyone does seem to agree on one thing though: with ARC turned off, the receiver will pass a 5 Hz signal with no problem.

I searched but was unable to find any source which backs that up based on electrical (not inherently flawed acoustical) measurements. Not that I'm claiming I have evidence to the contrary.

I have seen measurements of the main unfiltered outputs which seem solid to 10Hz, at least without ARC, which is only an octave away from 5Hz.

 

[mtrycrafts]

There were definitely others, but Master & Commander seemed to get the most people up in arms.

I just found the dts DVD for $1.58 used and ordered it lol.

And shipping is.....

 

[j_garcia]

And shipping is.....

$4 So still not bad.

 

[dolynick]

Thank you so much for sharing this. It does at least confirm that there is no hard cut at 15 hz, using ARC genisys, which is awesome. There was another gentleman, elsewhere that confirmed this on his AVM90 as well. I cant say for 100% certain, but I feel its safe to assume my MRX 1140 should be no different with ARC Genisys.

I have to ask what microphone are you using?

The supplied microphone in the ARC kit for ARC tuning.

The REW measurements were done with a UMIK-1. I start my measurements at 10Hz only though. The data starts at ~12.5Hz because there is a delay in the PC's audio system. But that's generally below where I'm concerned about trying to tune anyways.

The one thing we all agree on is that ARC correction stops at 15 Hz. But I'm getting conflicting info on whether Anthem receivers will actually pass frequencies below 15 Hz when ARC is turned on. Some guys say yes, but others—including a tech from Anthem—say it cuts it off.
Everyone does seem to agree on one thing though: with ARC turned off, the receiver will pass a 5 Hz signal with no problem. Honestly, I'm just going to test it both ways myself once everything is hooked up.

Yes. The lowest correction point in ARC is 15Hz.

I checked my ARC file for that particular room and correction tuning. That sub is using a 15Hz correction setting and a 3rd order roll-off beyond that. It does look like the roll-off below 15Hz is about that but I cannot be entirely certain and it could just be coincidence that the natural roll off of the driver is similar (It's a JL Fathom).

I suspect that the roll-off doesn't apply because in my other system, I use a much higher correction point for that sub and a much steeper roll-off and then let the sub/system do what it does below. The REW measurements clearly show output coming back up after the roll-off point and null it's rolling off into. (If you're curious to see those measurements and the ARC settings for that, you can view them here: https://forums.audioholics.com/forums/threads/living-room-system.128281/post-1687258 )

Also, the above tuning was done on my MRX-540 8k. The REW measurements post tuning also show output down to the same ~12.5Hz point.

 

[TLS Guy]

The one thing we all agree on is that ARC correction stops at 15 Hz. But I'm getting conflicting info on whether Anthem receivers will actually pass frequencies below 15 Hz when ARC is turned on. Some guys say yes, but others—including a tech from Anthem—say it cuts it off.
Everyone does seem to agree on one thing though: with ARC turned off, the receiver will pass a 5 Hz signal with no problem. Honestly, I'm just going to test it both ways myself once everything is hooked up.

So, here is your model. I did put the correct x-max in my previous model.

With the reduction in box volume below the optimal sealed volume, there is some degradation. The native F3 has moved up to 44.97 Hz, and so Eq will need to be increased. So maximum acoustic power at 20 Hz is 115 watts. which will produce 112 db. at 1 meter. You need to high pass the driver and cut it off at 20 Hz, otherwise you certainly risk driver damage.

The good news it that these will still be very good sealed subs and well to the top of the pack.

Pursuing infrasonic frequencies is not a fruitful endeavor, and risks damaging your drivers, which would be a pity, as to me at least they appear to be excellent drivers for sealed application.

So, 12 db. per octave boost starting at 44 Hz and high pass them at least 12 db. per octave at 20 Hz. That should give you nice subs that have a good long life.

 

[Allen Vos]

So, here is your model. I did put the correct x-max in my previous model.

With the reduction in box volume below the optimal sealed volume, there is some degradation. The native F3 has moved up to 44.97 Hz, and so Eq will need to be increased. So maximum acoustic power at 20 Hz is 115 watts. which will produce 112 db. at 1 meter. You need to high pass the driver and cut it off at 20 Hz, otherwise you certainly risk driver damage.

The good news it that these will still be very good sealed subs and well to the top of the pack.

Pursuing infrasonic frequencies is not a fruitful endeavor, and risks damaging your drivers, which would be a pity, as to me at least they appear to be excellent drivers for sealed application.

So, 12 db. per octave boost starting at 44 Hz and high pass them at least 12 db. per octave at 20 Hz. That should give you nice subs that have a good long life.

Thank you for adjusting the model for the box size. However, you did not answer my questions and instead focused on personal opinions.

Your model lists XMAX at 34mm, but the Mach 5 Audio website explicitly states 29mm of one-way linear travel. Furthermore, your model shows a cone excursion of 17mm at 5 hz, yet you claim the driver will suffer damage below 20 Hz. This is contradictory, considering XMAX is 29mm.

Many users run these subwoofers down to 10-15 Hz without issue, and I have personally seen an SPL graph confirming this level of performance. In fact, the subwoofer's actual designer states they can play down to 0 Hz (DC).

This type of misinformation is exactly why you faced pushback earlier in the thread. What concerns me most is that I have entered the exact same data into my own modeling software, yet we are seeing completely different results. While I appreciate your time, I need factual, consistent data rather than personal opinions to find this credible.

 

[TLS Guy]

Thank you for adjusting the model for the box size. However, you did not answer my questions and instead focused on personal opinions.

Your model lists XMAX at 34mm, but the Mach 5 Audio website explicitly states 29mm of one-way linear travel. Furthermore, your model shows a cone excursion of 17mm at 5 hz, yet you claim the driver will suffer damage below 20 Hz. This is contradictory, considering XMAX is 29mm.

Many users run these subwoofers down to 10-15 Hz without issue, and I have personally seen an SPL graph confirming this level of performance. In fact, the subwoofer's actual designer states they can play down to 0 Hz (DC).

This type of misinformation is exactly why you faced pushback earlier in the thread. What concerns me most is that I have entered the exact same data into my own modeling software, yet we are seeing completely different results. While I appreciate your time, I need factual, consistent data rather than personal opinions to find this credible.

The first issue is that the high pass filter will not be a brick wall. The usual slope is 12db/octave so the sub would not be 12db down until 10 Hz. and only 6db. down at 15 Hz, which with room gain will give you good output to 15 Hz. All sealed designs should be high passed at around 20 Hz or higher, as the boost can get very destructive of the drivers. So, the model shows that you will have very good strong bass and hopefully units that will stand the test of time. Whether xmax is 29 or 34 mm is irrelevant as you are not going to get the driver close to xmax. Even if you drove it down to 12 Hz you still would not run it out of X-Max. However, you can see that below 20 Hz and especially 15 Hz, output is not increasing as power is increased. So, the right design is to high pass at 20 Hz. The drivers will thank you! As with the design, max cone displacement is around 15 mm. Chasing those sort of low frequency numbers is not wise or sensible. I have given you a good design and it will do everything you desire, and be reliable.

 

[Allen Vos]

The first issue is that the high pass filter will not be a brick wall. The usual slope is 12db/octave so the sub would not be 12db down until 10 Hz. and only 6db. down at 15 Hz, which with room gain will give you good output to 15 Hz. All sealed designs should be high passed at around 20 Hz or higher, as the boost can get very destructive of the drivers. So, the model shows that you will have very good strong bass and hopefully units that will stand the test of time. Whether xmax is 29 or 34 mm is irrelevant as you are not going to get the driver close to xmax. Even if you drove it down to 12 Hz you still would not run it out of X-Max. However, you can see that below 20 Hz and especially 15 Hz, output is not increasing as power is increased. So, the right design is to high pass at 20 Hz. The drivers will thank you! As with the design, max cone displacement is around 15 mm. Chasing those sort of low frequency numbers is not wise or sensible. I have given you a good design and it will do everything you desire, and be reliable.

Please keep in mind that my build uses four of these subwoofers. According to WinISD, applying 1200 watts per sub increases the 5 Hz SPL from 85 dB (single driver) to roughly 97 dB. At 10 Hz, the four-sub array reaches 110 dB. This represents raw output, as I have not yet factored in room correction or cabin gain.
Your modeling still contradicts the evidence. The designer and manufacturer explicitly stated these drivers can play down to DC, and he certainly understand the mechanical limits better than anyone. Between the designer's specifications and real-world feedback from users successfully hitting 10 Hz, your conclusions simply do not align with the facts.