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Subwoofer Comparison

Tom C

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IMO this test is also the way it should work with speakers, well, in a perfect world where THD was replaced with a measure that had a solid connection to audibility anyway. S&R does testing to thresholds of distortion(10% for low bass, 3% for everything else, respectively) and I find this more useful than the fixed 86/96dB sweeps, since it actually gives you information on how loud a speaker will go before distortion becomes a big problem. However, this test requires far more data than the simplistic 86/96dB single sweeps. Truly, measuring subs is a heroic effort and we should be grateful for the data we have. %THD is an inherently weak form of information about distortion anyway so you can't use it very precisely.

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I don't think it's a lot... There's little evidence it would be audible with music. With test tones, yes. CEA2010 isn't just about %THD either because it has different thresholds for different harmonics at different frequencies. And 118dB SPL ground plane with no room gain is absurdly loud. The Rythmik F18 only has about 1.3% distortion at 125hz/100dB SPL. Plus not many people are crossing subs that high.

The research into audibility of distortion is complicated and nobody has a good standard measure that can be related to hearing. So you kind of either take CEA2010 as good enough, or you only buy a sub off data-bass I guess because it's one of the few(only?) places with more detailed distortion measurements.

But again, you can very easily reduce risk of audible issues by buying more and bigger subs than you need. That's why I'm planning to replace my SB12-NSD with 2x Arendal 1723 2S, lol.
That leads to the question of how to choose multiple subs. If you have a Audioholics medium size room and plan a four-unit setup, I would think you could use subs rated for small rooms, since you will have four of them. I’m considering two units tuned low, plus two tuned higher.
 

Sancus

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That leads to the question of how to choose multiple subs. If you have a Audioholics medium size room and plan a four-unit setup, I would think you could use subs rated for small rooms, since you will have four of them. I’m considering two units tuned low, plus two tuned higher.

I pick subs based on 20-30hz CEA2010 because any decently sized(12"+) sub has huge output at 40hz+. The Audioholics page on their rating system explains pretty thoroughly what SPLs you can expect from their different ratings. Note the +12dB from corner loading vs ground plane. The page also explains how much bass you'd need if you listen at film reference level(123dB), but since most people don't as they state, 115dB is usually plenty.

You should always use identical subs for a multi-sub system. No bass management system I'm aware of can be set to alter signal levels based on individual sub capability, and while it's probably possible with full manual EQ/delay/level settings, I can't see how it would be worth the added complication. 4 good subs that can play low will play at ear-destroying levels high.
 

temps

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Added 3 new models with CEA-2010-A data.
Data was provided by funkaudio.ca themselves, but I missed it previously, as it wasn't shown clearly.
These were the models: 21.0L, 21.0LX, and 24.0.
All of them are 'Extreme' rated, but they are completely overpriced.
It really makes JTR Speaker's subwoofers a bargain! ;)

I've hit a new milestone...we now have CEA-2010-A data on 300 subwoofer models. Amazing!
the JTR RS1 looks like a Funk Audio 18.0SE copy, with massively inferior finishing, less output, and no user configurable DSP ... for more money? I don't think I've ever seen Funk undercut anybody's pricing before o_O

Cabinet finishing on Funk is miles better than anything JTR has ever done, which is disappointing. JTR's been at it for years, their pricing has gone up, but the products continue to be complete eyesores with zero WAF. Funks are ultra high end furniture that just happen to also be incredible subwoofers... I have flirted with the idea of upgrading from my 18.0SE a few times but why bother? I never even come close to reaching its limits and movies hardly ever use infrabass anymore
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Sancus

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the JTR RS1 looks like a Funk Audio 18.0SE copy, with massively inferior finishing, less output, and no user configurable DSP ... for more money? I don't think I've ever seen Funk undercut anybody's pricing before

It seems very odd to me to accuse a sealed box of being a 'copy' when all the relevant attributes are different? The drivers are different and the plate amps are clearly very different as well.

Funk Audio states that their current 18.0E(which is an update of the 18.0SE) is similar in output to their 18.0, which has 4.5dB LESS 20hz CEA2010 than the JTR RS1 according to the spreadsheet(Funk - 106.6, JTR 111.1). So the performance is very different as well.

I'm not saying Funk Audio is terrible, they are definitely a lot prettier! But JTR is making products for dedicated HT spaces where finishes are less important, not for the living room. The price difference is $149($2750 vs $2899) which doesn't seem significant.
 

temps

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It seems very odd to me to accuse a sealed box of being a 'copy' when all the relevant attributes are different? The drivers are different and the plate amps are clearly very different as well.
The dimensions are identical. The driver is clearly inferior and required a ton of DSP to correct its response... the amp is also inferior. It also apparently uses a normal magnet instead of neodymium because the JTR manages to weigh 20 pounds more somehow.

Funk Audio states that their current 18.0E(which is an update of the 18.0SE) is similar in output to their 18.0, which has 4.5dB LESS 20hz CEA2010 than the JTR RS1 according to the spreadsheet(Funk - 106.6, JTR 111.1). So the performance is very different as well.
more output below 40hz, less above, and more distortion throughout...

I'm not saying Funk Audio is terrible, they are definitely a lot prettier! But JTR is making products for dedicated HT spaces where finishes are less important, not for the living room. The price difference is $149($2750 vs $2899) which doesn't seem significant.
it is very significant when the cheaper of the two has 10 band parametric EQ and is in a completely, entirely different realm of finishing
 

Sancus

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The driver is clearly inferior and required a ton of DSP to correct its response... the amp is also inferior

more output below 40hz, less above, and more distortion throughout...

Please explain/justify your statements that either is inferior or has more distortion. The numbers indicate the opposite. The JTR has substantially better performance.

Output above 40Hz is irrelevant, it's already so high it won't ever matter, especially if you are correctly using multiple subs.

it is very significant when the cheaper of the two has 10 band parametric EQ and is in a completely, entirely different realm of finishing

Sure, they're different products. Neither is a "copy". Manual DSP is a 100% worthless feature in a $3000 HT sub. Anyone buying these is using them with an AVR/AVP that has much more powerful DSP options.
 

temps

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Please explain/justify your statements that either is inferior or has more distortion. The numbers indicate the opposite. The JTR has substantially better performance.
Funk Data-Bass: Subwoofer Measurements (data-bass.com) notice how the BOTTOM line is the Funk's 115dB test. Top line is 120
JTR JTR Captivator RS1 Subwoofer Conclusion | Audioholics the TOP line is the JTR's 114dB test

Funny how the Funk performs about the same as the JTR at a level 6dB higher. Notice the tails on the treble side of the distortion chart.. the Funk Audio is so clean you could make a 3 way speaker simply by sitting a bookshelf on top of it, whereas the JTR is clearly hurtling out of its comfort zone above 90hz. Also notice the JTR required a massive amount of filtering to correct its response. DSP has been used to cover for design deficiencies, and sure the Funk is filtered as well but nowhere near as much.

I'm also fairly sure with room gain factored in, both subs have more output at every frequency than anybody would ever need unless your primary goal is to antagonize your neighbors. So why not go with the cleaner, prettier, cheaper sub?

Sure, they're different products. Neither is a "copy". Manual DSP is a 100% worthless feature in a $3000 HT sub. Anyone buying these is using them with an AVR/AVP that has much more powerful DSP options.
That's simply ignorant. I bought one and don't run it off an AVR all the time... I have a manual, one seat correction profile loaded into the Funk when I want to play my music off a good DAC. The JTR would go uncorrected and would be completely useless in the same application.

The Funk predates the JTR by almost a decade. The dimensions on the JTR are identical, the amplification is identical, and they probably wish the driver was identical too but it doesn't look like they had the engineering capability to manage that. You'd also have the option of DIYing a subwoofer using the same drivers as the Funk and come in well under the JTR's price tag. A hobbyist wouldn't stand a chance of approaching Funk build quality but would have little trouble making something nicer than a JTR for less.
 

Sancus

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Funk Data-Bass: Subwoofer Measurements (data-bass.com) notice how the BOTTOM line is the Funk's 115dB test. Top line is 120
JTR JTR Captivator RS1 Subwoofer Conclusion | Audioholics the TOP line is the JTR's 114dB test

You didn't actually link to any graphs, so I assume you're talking about the generic sweep vs distortion. Of course, that is not useful because the JTR compresses less than the Funk Audio does, which means none of those numbers are comparable. That is why we have CEA2010, which is a much better test, and proves the JTR has better performance.

That's simply ignorant. I bought one and don't run it off an AVR all the time... I have a manual, one seat correction profile loaded into the Funk when I want to play my music off a good DAC. The JTR would go uncorrected and would be completely useless in the same application.

Calling me "ignorant" makes it clear to me you're deeply emotionally invested in proving Funk Audio is the best or something so I don't think it is worth continuing this, sorry.
 
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richard12511

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the JTR RS1 looks like a Funk Audio 18.0SE copy, with massively inferior finishing, less output, and no user configurable DSP ... for more money? I don't think I've ever seen Funk undercut anybody's pricing before o_O

Cabinet finishing on Funk is miles better than anything JTR has ever done, which is disappointing. JTR's been at it for years, their pricing has gone up, but the products continue to be complete eyesores with zero WAF. Funks are ultra high end furniture that just happen to also be incredible subwoofers... I have flirted with the idea of upgrading from my 18.0SE a few times but why bother? I never even come close to reaching its limits and movies hardly ever use infrabass anymore
View attachment 127071

The RS1 is a much better sub, though. At least objectively. I agree that the Funk finish is much nicer, but sound wise, it's worse. Check the sub 20Hz performance. As @Sancus correctly pointed out, 20Hz and below is all that really matters with subs of this size, as that is going to be your limiting factor. You need multiple of the Funks to match the distortion limited output of the single RS1, so the RS1 is definitely the better value, objectively.

I agree about JTR price raise, though. Unfortunate, for sure, though I guess caused by Covid. With the price raise, I generally think it's better to go with Rythmik at this point. JTR definitely has Funk beat in terms of price/performance. That's not saying much, though, as Funks are generally quite overpriced on pure performance(paying for aesthetics). Rythmik generally has JTR beat at this point, at least imo.

BTW, JTR will do any finish you want for an extra $300? I've never done it, but from what I heard it takes a lot longer to get your sub if you do.
 
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beaRA

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You should always use identical subs for a multi-sub system. No bass management system I'm aware of can be set to alter signal levels based on individual sub capability, and while it's probably possible with full manual EQ/delay/level settings, I can't see how it would be worth the added complication.
My understanding is that this is true of the Welti approach, but not for the Geddes approach. I believe the miniDSP 2x4 allows for individual gain & delay adjustments for integrating different size and asymmetrically placed subwoofers. Has anyone here had luck with the Geddes approach or even compared both approaches in their space?
 

richard12511

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My understanding is that this is true of the Welti approach, but not for the Geddes approach. I believe the miniDSP 2x4 allows for individual gain & delay adjustments for integrating different size and asymmetrically placed subwoofers. Has anyone here had luck with the Geddes approach or even compared both approaches in their space?

I tend to take a bit of advice from both Welti and Geddes. I like that the Geddes approach can work with odd number of subs, as well as working better with non rectangular rooms. I have never had success running the mains full range, though, so I tend to take the Welti approach there. If I had JTR 215RTs instead of the 212(or now the 8351b)s I might try the Geddes full range "mains as additional subs" approach. I've tried running my 8351s full range as additional subs to the RS2s, but I always end up getting the dreaded red lights. How do you keep your "smaller subs" from becoming the system limiting factor?
 

beaRA

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How do you keep your "smaller subs" from becoming the system limiting factor?
My interpretation is that you can use overlapping bass sources with different bands to help smooth out the response. Say you place the large sub to avoid inconsistency in the <40Hz region, then smaller subs can contribute to smoothing out the response >40Hz where they tend to have plenty of output. I have only played around with mixing a Rythmik E15 and SVS SB-1000, but I don't currently have a way to explore this approach properly with 3+ subs.
 

HighImpactAV

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The Funk predates the JTR by almost a decade. The dimensions on the JTR are identical, the amplification is identical, and they probably wish the driver was identical too but it doesn't look like they had the engineering capability to manage that. You'd also have the option of DIYing a subwoofer using the same drivers as the Funk and come in well under the JTR's price tag. A hobbyist wouldn't stand a chance of approaching Funk build quality but would have little trouble making something nicer than a JTR for less.
I was at the initial introduction of the JTR S1 on January 14, 2012 with a custom driver completely designed by JTR. Prior to this he had a gentleman's agreement with Seaton Sound to only produce ported subs and Seaton would do sealed subs. I'm pretty sure that at that time, Funk wasn't designing their own drivers and was using Aurasound and TC Sounds drivers in their subs. The current JTR driver is not inferior nor requires "a ton of DSP to correct its response ."
 

temps

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You didn't actually link to any graphs, so I assume you're talking about the generic sweep vs distortion. Of course, that is not useful because the JTR compresses less than the Funk Audio does, which means none of those numbers are comparable. That is why we have CEA2010, which is a much better test, and proves the JTR has better performance.
I assumed you would do the 4 clicks necessary to get informed on your own. You didn't - hence, ignorant.... I'm wondering what you're even looking at here? At 120dB the Funk is precisely spaced 5dB above its 115dB sweep, all the way down to 10hz, except for a tiny little blip at 100hz. Audioholics charts are almost unreadable but clearly, the JTR does not manage to do the same and it was only tested to 115dB.

The RS1 is a much better sub, though. At least objectively.
bizarre to use the word "objective" here when your next assertion is 100% subjective
@Sancus correctly pointed out, 20Hz and below is all that really matters with subs of this size
This is simply not true. You are literally talking to somebody who bought one of these to insure he would have practically unlimited clean headroom on music material, no matter how big of a room I ever put the sub in. That it has good enough response <20hz was just a bonus.
I agree that the Funk finish is much nicer, but sound wise, it's worse.
Yes by being less distorted throughout its range, it sounds worse. Naturally. Of course, yes. There definitely is no advantage to having <0.2% distortion over 80hz. That definitely doesn't help it blend with your mains at all, nope.
Rythmik generally has JTR beat at this point, at least imo.
I mean, do they or don't they? You have a very easy time making Objective Pronouncements. Should be quite easy to pick a winner here, no?
BTW, JTR will do any finish you want for an extra $300? I've never done it, but from what I heard it takes a lot longer to get your sub if you do.
Their cabinetry is and always has been so inept I think you'd have to be out of your mind to take that option.

The current JTR driver is not inferior nor requires "a ton of DSP to correct its response ."
look at the group delay chart... I mean, they had no processing power left for any more than 1 band of EQ?
 
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richard12511

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bizarre to use the word "objective" here when your next assertion is 100% subjective

That's not really a subjective opinion. That's an objective reality of normal household conditions. Extra headroom at frequencies at which you are not output limited are 100% meaningless. 200dB at 90Hz is 0% better than 120dB at 90Hz in a typical house, as both are entirely unlimited. If you live in a commercial theater, then things are different, and that's why those subs usually prioritize 30-40Hz output. I'm speaking of home use.

This is simply not true. You are literally talking to somebody who bought one of these to insure he would have practically unlimited clean headroom on music material, no matter how big of a room I ever put the sub in. That it has good enough response <20hz was just a bonus.

What is your listening distance? Maybe it's large enough where the Funk's extra 40Hz+ output really is better. It would have to be huge, though(like 8m+ at least), I would think.

I understand that there's an emotional investment, but we're just looking at objective CEA-2010 data here. I'm not trying to say you made the wrong choice. In fact, based on a couple things you've said, I think you actually made the correct choice, namely

Their cabinetry is and always has been so inept I think you'd have to be out of your mind to take that option.

We have to live with these items, after all. If the cabinetry is too ugly for you, then I can see where it would be worth it to spend a bit more for a little less performance.

I chimed in not to say you made the wrong choice, but just to make it more clear to others reading this that by going with Funk you are paying a premium for the gorgeous cabinetry. To many out there, that premium is probably worth it. Funk makes outstanding subs that also look outstanding. However, for someone who doesn't care as much about aesthetics(like me), Rythmik, JTR, PSA, Arendal, etc. offer noticeably better performance for the same dollar in normal sized living rooms.

Also, it seems strange to me to call another 18 sub a copy of another when 1. The cabinet is different, 2. the amp is different(exactly equal), 3. The driver is different(JTR driver is better). By this same logic, you could say that the Funk is a copy of any 18" sub that came before it. Essentially all subs are copies of any same driver size sub that came before them? Is that what we're saying now? :p When did the 18.0E come out(genuinely curious)?. When did the S1 come out(again, genuinely curious)?

Sorry for the long post. It just want to make things more clear for people in the market who may be using this list for shopping purposes. People can view @sweetchaos excellent spreadsheet and compare the CEA-2010 performance of JTR vs Funk for themselves and see what we're talking about. Then they can decide what's more important to them. I'll try to lay it out a little below, though.

A few things to consider, for those in the market and reading along.

- Both subs are well below audible thresholds for distortion. JTR beats Funk here at some frequencies and vice versa, but it's essentially irrelevant.
- Both subs have inaudible group delay. Again JTR is better at some frequencies, Funk at others, but it's irrelevant for both.
- Both subs have infinite headroom above 25Hz or so in room, so any performance above that is irrelevant(200dB is equivalent to 130dB @90Hz if the loudest you'll ever reach is 120dB).
- Focus especially on the distortion limited output below 20Hz, as that's usually the only difference with subs of this size(unless you live in a commercial theater :p). Extra headroom at frequencies where headroom is infinite matters not ;)

The Funk does have some real advantages, though:

1. 10 band parametric EQ. If you don't have a way to EQ, then this is basically an automatic win for Funk, as bass EQ is necessary for good sound. If you have other EQ though, (Dirac, Trinnov, Audyssey, etc.) then this is mostly irrelevant. @temps , you mentioned that you use this, so it's definitely a huge plus in your situation. An EQed sub will always sound better than an un-EQed sub, no matter how much more sub 20Hz output the un-EQed sub has.
2. Different high pass and low pass slope options. This is really awesome and definitely an automatic win if you don't have another way to get this with the JTR(miniDSP2x4HD). Not many subs that I can think of provide this, so kudos to Funk for doing this.
3. Aesthetics. The cabinetry of Funk subwoofers is outstanding, and if you're someone who cares a lot about how it looks, this alone might be worth the loss in performance.

All of those matter, and while the 4th one is the only one that applies to my situation(with a DDRC88A and 2x4HD), it was important enough to me that at one time I was seriously considering Funk. I ended up getting a ~30-40% off (black friday + buying multiple)on the RS2s, but had that not happened, I really was considering Funk.

I view Funk kinda like the Salk of high performance subwoofers. Not as good price/performance as the best out there (HSU > Rythmik > JTR, etc.), but legitimately awesome performance, and much nicer to look at. Similar to how you can buy the Salk BMR for a little more than the Philharmonic BMR, with the difference being in the finish.

Back to price/performance, though(and for those reading). I actually don't think either of these subs(Funk 18.0 or JTR RS1) are the best values out there. Ported variants generally offer much better price/performance, and I'm very skeptical of any audible "sealed advantage" for music over really lowed tuned ported subs. I think this is mostly based on principals that used to be true, but no longer are. I don't by any means claim this as fact, though. It's just my current view.

If you really want sealed, the RS2 is a much better value than the RS1 imo. It gives you twice the performance for less than twice the price. Comparing the three sealed options (18.0, RS1, RS2) on pure price/performance at the point where the distortion becomes too high to meet spec(subtract $150 for the Funk if you don't need a grill):

Rich (BB code):
Funk 18.0($4,300), JTR RS1($2,899), JTR S2 ($3,499) , ~JTR RS2($3,899)
-----------------------------------------------------------------------
10Hz: 94.4,        96.1,            100.3,            ~101/102.3
12Hz: 98.5,        100.1,           103.3,            ~104/105.3
15hz: 102.2,       105.4,           108.7,            ~109/110.7
20Hz: 106.6,       111.1,           115.1,            ~116/117.1
25Hz: 111.8,       115.6,           119.7,            ~120/121.7
30Hz: 117.9,       119.6,           124.8,            ~125/126.8

By 30Hz all 3 are already above reference in anechoic conditions, so anything above that becomes meaningless in a normal house with room gain. In a commercial sized theater space, note that the Funk passes the RS1 by about 2dB(and stays that way) above 40Hz, so it might be a better subwoofer for that environment. If you've got a theater that big, though, you'd be even much better off with something like the JTR Orbit Shifter LFU, Orbit Shifter Pro, or one of the big JBL Cinema subs.

Also, even though the RS1 does have better performance, the difference isn't going to be large. They will sound identical above 20Hz or so at normal volumes. Below 25Hz the RS1 will only sound better if you listen at movie theater levels, and by 30Hz they'll be identical. For music, below 30Hz is a very small minority of content(though it does exist). Vast majority of content I'd be willing to bet they sound exactly the same at most levels that people listen to.

Something like the Rythmik FV25 or Captivator 4000ULF is an even better value(imo).

BTW, I just noticed you're talking about the 18OE. Where are you seeing CEA-2010 data for that? I see a note on the Funk site saying "Very similar in overall performance to our 18.0, more information coming soon." But, "Very similar" to me implies close, but not as good, especially considering that it's $1,400 cheaper. I can see your "copy" point more, now, though, given that the JTR RS1 is just $1 cheaper :D. I still disagree that it's a copy, though ;).

Has Nathan given any more info than that? Even if just an estimate (ex: 1dB less here, 2dB less here), I can update the comparison above with a "~"(similar to how I've done with the RS2).

Since I couldn't find CEA-2010 data for the 18.0E, I had to use the more expensive 18.0 for comparison, but I'm assuming the 0E is just a little worse.
 
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pozz

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I appreciate the patience you folks have shown. I see now that what is implied in the standard is that as frequency gets very low, a progressively higher level of distortion is tolerated. When you think about it, can a person really sense distortion at all in a 10 or 15 Hz impulse? Is there any distortion in an earthquake, or a cement truck rumbling by? Probably not, but maybe some studies have shown it can, or maybe they just had to establish a definition somehow. I imagine at 10 Hz, I could tolerate 100% or multiples more. Things change a lot at 30Hz, where the standard becomes much stricter. At 125Hz, 2.7% seems like a lot of distortion to tolerate (more lenient than strict), but may be easier to accept when there are other high quality speakers present in the system reproducing the program material with less distortion (in which case the overall system SINAD would be something less than 2.7%). Is that an argument for the Geddes approach to subwoofer integration?
It seems an unfamiliar way to present the data. When a DAC or full-range speaker is tested, we’re used to seeing distortion level measured at a particular frequency with a sweep of power output levels, or a fixed output level and a frequency sweep. But in subwoofer world, you hold frequency constant, and increase the output until you hit the ceiling on a defined distortion level. It must work OK to do it that way, but it takes a little re-alignment of thought to internalize.
I compiled research on low frequency hearing thesholds: https://www.audiosciencereview.com/...-pathways-for-hearing-bass.22167/#post-737109

In the tests done by Yeowart et al they were careful to have at least 30dB distortion free range for any given infrasonic frequency under test. That's a limit of about 3%. Not really a defined threshold, of course, but something to work with.

It should be remembered that CEA2010 testing is done with bursts, for which distortion thresholds are much higher than for any sustained signal.
 

temps

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What is your listening distance? Maybe it's large enough where the Funk's extra 40Hz+ output really is better. It would have to be huge, though(like 8m+ at least), I would think.
At one time it was quite long, and it is in a enormous room. After re-organizing the furniture my listening distance has gotten very short so I'm starting to debate ditching the Funk and going to a much smaller pair of subwoofers as I never have the occasion to turn it up anymore... and since the Mouse House has taken everything over, movies that actually call for a lot of <30hz output have gotten very few and far between. Basically it feels like I have a 2,000 horsepower dragster parked in my garage, but I only need a commuter car.
I understand that there's an emotional investment, but we're just looking at objective CEA-2010 data here. I'm not trying to say you made the wrong choice. In fact, based on a couple things you've said, I think you actually made the correct choice, namely
To clarify I think that, their entry level subs aside, JTR does have an enormous advantage in performance-per-dollar. It's not even close. The RS1 is the only one that I thought that maybe it isn't true. And I did want to draw some attention to where a lot of your money goes when you buy a Funk, which the spreadsheet & your original post didn't really acknowledge.

I actually bought the Funk because it was, for what I needed, by far the best subwoofer available at the time that was measured on data-bass. Pre-dated the Rythmik F18 which is absolutely the direction I would go in today. Your spreadsheet is a huge help to the community - thank you for the good work.
- Both subs are well below audible thresholds for distortion. JTR beats Funk here at some frequencies and vice versa, but it's essentially irrelevant.
I have gone down this road a few times on the forum and apparently nobody shares my opinion that less distortion, is always better - regardless of any audibility threshold. 0 is always the target. Things may be inaudible in a steady sweep but may become audible on music material. I hope more insight into IMD is done, standard tests are developed, etc. so we can explore that a bit more in the future.
Has Nathan given any more info than that? Even if just an estimate (ex: 1dB less here, 2dB less here), I can update the comparison above with a "~"(similar to how I've done with the RS2).
I avoid talking to Nathan because the conversations tend to be so expensive :D so no, I was operating the assumption that the 18.0E is equivalent to the 18.0. Yes the cost has come down but I assume it's because the drivers have been made for quite some time and all the tooling is paid off, apprentice in the shop can build the square cabinets to standard, maybe everything is fixtured, the brand is doing better as a whole and pushing more volume, etc

Also I apologize for the general tenor of my posts. Under a lot of stress right now and I've gone off my Forum-Talk Baseline of "quite dickish" to "complete asshole." I'll be taking a bit of a break here until I can get my head on straight.
 

Sancus

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My understanding is that this is true of the Welti approach, but not for the Geddes approach. I believe the miniDSP 2x4 allows for individual gain & delay adjustments for integrating different size and asymmetrically placed subwoofers. Has anyone here had luck with the Geddes approach or even compared both approaches in their space?

Well when I said 'bass management system' I was referring to automated systems eg Audyssey, Trinnov Optimizer, Dirac Bass Control, etc. I'm not super familiar with the Geddes approach, I've only read a couple of short papers from him. What I read indicated that it would be unsuitable for multichannel audio and since I don't want two completely different signal chains in my system I discarded it.

I did some recent Googling and I couldn't actually figure out one source that fully explains Geddes on subwoofers. There are various short papers written by him, and some videos, and they all seem to contain small contradictions in methodology and requirements. For example in one of the early papers he says that EQing the mains based on room data should never be done(at what frequency range? My room contains issues at 100-500hz that actually exceed the low bass problems, and EQing them audibly fixes a lot..). But then in this video he states that not being able to EQ mains was a limitation imposed by the customer's setup...?

Geddes states that the mains should take the full signal and he doesn't seem to address the possibility of them being overloaded as a result. Some other sources indicate he assumes large, high output mains. In multichannel the LFE signal is way too loud for it to be realistically mixed into the mains unless yours have the same output as true subs. Also, as he notes in the video, the actual levels that each of the bass sources will play is unintuitive and calculated by his computer program. But there's no way to predict it in advance, and it varies by huge amounts! How can you compensate with a single gain setting if one of your small subs is tasked to play 20hz at a high level? The page I linked above states that you could use subs of different size by placing the smaller ones closer to the listening position, and that may be true on average, but it ignores the fact that the filters could easily render small listening distances differences irrelevant.

Finally, I think you need to send your measurements to him to actually get the real solutions? According to the MSO page listing approaches, "Despite discussion in that thread spanning twelve years, he's never described specifics of how he computes the per-sub filter parameter values."

This all seems really complicated, confusing, and lacking information. MSO supports an optimization strategy using the Geddes approach(in the most high-level sense) and it addresses various additional complications including the dissimilar subwoofer issue. They have you high-pass your mains if they're not "of closed-box type, with high power handling and an anechoic low-frequency cutoff of 80 - 90 Hz".

Dirac claimed that their Bass Control would eventually be able to use mains as supplementary bass sources, but as far as I know that isn't working yet. In theory it should be possible for software to programmatically measure your mains limitations and tailor the resulting matrix of EQ solutions for each bass source to match.

Honestly my long term plan is to just get a processor with Dirac :p
 

Usernome

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I did some recent Googling and I couldn't actually figure out one source that fully explains Geddes on subwoofers.

I think this article is a good practical explanation of how to setup subs the Geddes way with some of the theory as well.
 
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