Official Rythmik Audio Subwoofer thread - Page 673 - AVS Forum | Home Theater Discussions And Reviews
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post #20161 of 20188 Old 08-26-2015, 11:51 AM
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With one L12 I have measured 96-98dB in room at 20hz just before the limiting circuit kicks in.

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post #20162 of 20188 Old 08-26-2015, 12:01 PM
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Quote:
Originally Posted by DonH50 View Post
Hi Enrico,

First congrats on the wedding! Or "weeding", Freudian slip? Three daughters, no wonder you are working 24/7!

The XMC-1, like most AVRs and pre/pros (every one I have seen), is 12 V so that's OK. Never personally seen a negative voltage trigger output. I have an ET-3 but was able to dump it when I went to the XMC-1 since it has more trigger outputs. I thought of that (great minds and all that) but was checking to see what I could get away with; I can use it if needed. I am using an X10 system to power on my current subs (no trigger input on the PEQ2 amps) but can avoid yet more power switches if I can use the trigger inputs. Besides, I bought trigger extension cables, but not more X10 power switches, and am both cheap and lazy!

FYI, 200 mA is very high; several AVRs I looked at a while back were limited to 50 mA. I do not know if there is an industry standard for the trigger circuits.

Thanks! - Don
Yes, 200mA is a bit exaggerated but I wanted to be on the safe side!! My Emotiva XPA-3 12V trigger out is rated up to 100mA and my XPA-200 is rated up to 50mA. I think is safe to assume that each of the four the XMC-1 12V trigger outs are 50mA?

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post #20163 of 20188 Old 08-26-2015, 01:27 PM
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Btw, I did ask Brian about the 12V trigger current draw but still waiting for his response. He is in China right now so it may take a little bit more than normal for him to respond via email.

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post #20164 of 20188 Old 08-26-2015, 01:37 PM
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I have rarely seen an output rated below 50 mA so I would guess that is safe. I have not looked and am not sure what if any standard defines trigger outputs; Brian might know, When I last looked it seemed a lot of AVRs did not list their trigger output capability. The XMC-1 manual and spec list online do not say. The majority of the ones I found were 100 mA with one (a Denon) only 25 or 50 mA.

I was mainly asking to see if I could parallel two outputs without sticking my ET-3 back in the system. If the trigger circuit goes into a transistor or op-amp buffer I'd expect very low current draw. If there is a pull-up or it goes straight into a relay then I'd expect higher current. I don't know what trigger inputs (or outputs) look like. I have a couple of service manuals at home, might have to investigate a bit.

Not in a big rush, no worries. For now I can stick the ET-3 back in, or maybe just gen up something to measure it since I am curious.

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post #20165 of 20188 Old 08-26-2015, 06:44 PM
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Quote:
Originally Posted by DonH50 View Post
I have rarely seen an output rated below 50 mA so I would guess that is safe. I have not looked and am not sure what if any standard defines trigger outputs; Brian might know, When I last looked it seemed a lot of AVRs did not list their trigger output capability. The XMC-1 manual and spec list online do not say. The majority of the ones I found were 100 mA with one (a Denon) only 25 or 50 mA.

I was mainly asking to see if I could parallel two outputs without sticking my ET-3 back in the system. If the trigger circuit goes into a transistor or op-amp buffer I'd expect very low current draw. If there is a pull-up or it goes straight into a relay then I'd expect higher current. I don't know what trigger inputs (or outputs) look like. I have a couple of service manuals at home, might have to investigate a bit.

Not in a big rush, no worries. For now I can stick the ET-3 back in, or maybe just gen up something to measure it since I am curious.
OK so definitely I was a bit off. The current draw of the XLR2/XLR3 amp 12V trigger input is only 4mA I think you are totally safe splitting the trigger out on your XMC-1

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post #20166 of 20188 Old 08-26-2015, 08:15 PM
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Awesome, thanks Enrico, and please thank Brian for me (and safe travels)!

"After silence, that which best expresses the inexpressible, is music" - Aldous Huxley
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post #20167 of 20188 Old Yesterday, 05:00 AM
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How does the F15 compare to a higher end sub like the JL 13 or something of that price range?
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post #20168 of 20188 Old Yesterday, 06:31 AM
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I compared to Velodyne, Paradigm, ML, B&W, and a few others I have forgotten that were mostly in the $3k to $5k (retail) range. To my ears Rythmik is "higher-end". To be fair, it did not sound significantly better than the much more expensive subs, and some of them had higher output with lower distortion despite the servo, but by and large my Rythmik equaled or bettered the pricey subs for sound quality. Essentially I could pay $1k to $1.5k with Rythmik, or get similar performance for $3k to $5k from a traditional brand.

I do not really remember JL but IIRC it was a great sub. I did not have much time to listen to one and never in my system (nor many of the others). The one I was looking at was competitive but still about 2x Rythmik. Some (perhaps many) of the $1k to $2k subs I found to exhibit excessive "ringing" that muddied the sound so I had to bump my price range to find one that I felt would integrate well with my planar speakers. Then I found Rythmik -- I bought a pair of F12's for less than I had (reluctantly) planned to spend on a single sub at a local store.

IME/IMO, YMMV, etc. - Don
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post #20169 of 20188 Old Yesterday, 02:26 PM
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Quote:
Originally Posted by checker9 View Post
Anyone got/heard a Rythmik L12? Is its output really has high as implied?

Per the Rythmik website subwoofer summary page, http://www.rythmikaudio.com/products1.html the L12, at 20 Hz max SPL, would be 1dB below the F12 which would be 9.5 dB below the VF15HP, which means the L12 would be 10.5dB below the FV15HP.

Per Databass, http://www.data-bass.com/systems the FV15HP produces 108.1 to 108.3 max 2 meter SPL at 20Hz in 2 and 1 port modes.

That would imply the L12 is around 97.5 dB at 20Hz.

For comparison, per Audioholics quoting a third party test, the SVS SB-2000 puts out 92.1 dB at 20 Hz and per Databass, the PSA XS-15SE is at 97.6 dB at 20 Hz and the SVS SB-13 Ultra is 96.5

That means the L12 would have the output of two SB-2000s, which has almost twice as powerful amplifier (500 WRMS on the SB-2000 vs 300 WRMS on the L12)
I will not read it like that. L12 should be comparable to SB-2000 with 1db or so difference at most. The reason Audioholic numbers are different from those of Data-bass is because the measurement distances are different.

The maximum output should be a concern only when you really want to push the subwoofer hard, which we don't do normally.

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post #20170 of 20188 Old Today, 01:39 AM
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How does the F15 compare to a higher end sub like the JL 13 or something of that price range?
In what world is JL high end? They are the automobile equivalent of Bose... some quality, but mostly name brand money scheming.
In an effort to add something helpful to that jeer, The F15 sub to JL 13W7 is like a Maserati compared to a Honda Accord.
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post #20171 of 20188 Old Today, 05:53 AM
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In what world is JL high end? They are the automobile equivalent of Bose... some quality, but mostly name brand money scheming.
In an effort to add something helpful to that jeer, The F15 sub to JL 13W7 is like a Maserati compared to a Honda Accord.
JL Audio is a high end manufacturer in the home theater and 2 channel music worlds. I have no experience with them in the auto world, so I can't comment on how they are in that space, but I do have direct exposure to their subwoofer products for the home. They are highly regarded for their exceptional engineering, construction and sound quality, and there is most definitely valid reasons why that is.

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post #20172 of 20188 Old Today, 06:45 AM
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Originally Posted by usaforce87 View Post
In what world is JL high end? They are the automobile equivalent of Bose... some quality, but mostly name brand money scheming.
In an effort to add something helpful to that jeer, The F15 sub to JL 13W7 is like a Maserati compared to a Honda Accord.
I have JL Audio subwoofers in my cars and they are really good. Very clean and accurate with no boomy sound. I have customers almost everyday asking if our products can be used for car audio application, unfortunately they are not suitable for car audio for many reasons but I always point them into JL Audio direction when car audio comes to the conversation.

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post #20173 of 20188 Old Today, 06:54 AM
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Originally Posted by enricoclaudio View Post
I have JL Audio subwoofers in my cars and they are really good. Very clean and accurate with no boomy sound. I have customers almost everyday asking if our products can be used for car audio application, unfortunately they are not suitable for car audio for many reasons but I always point them into JL Audio direction when car audio comes to the conversation.
Or point them towards Image Dynamics. I went from a JL Audio W3 to an ID V.4 and it was a significant improvement. At least in my opinion. I now have a single SI BM MK IV in my truck and it blows both away in sound quality and SPL.

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post #20174 of 20188 Old Today, 07:06 AM
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I dont know anything about JLAudio and they may be highly regarded for good reason. But $2600 for a 10" subwoofer seems a little Bose-ish to me.
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I dont know anything about JLAudio and they may be highly regarded for good reason. But $2600 for a 10" subwoofer seems a little Bose-ish to me.
Man, those two aren't even close. Just because something is expensive doesn't mean it's also overrated. JL Audio is definitely not aimed at the "best bang for the buck!" crowd, so for those folks they aren't on the shopping list. They're target audience is the discerning individual who wants exquisitely made US products.

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Man, those two aren't even close. Just because something is expensive doesn't mean it's also overrated. JL Audio is definitely not aimed at the "best bang for the buck!" crowd, so for those folks they aren't on the shopping list. They're target audience is the discerning individual who wants exquisitely made US products.
No wonder I havent heard of them. Im just a poor cheap ignorant audiophile wannabe.
I'll keep them in mind if I win the lottery though.
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I'm sure they're anticipating your future business with bated breath.

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Just for fun, JT. Edge of Tomorrow at reference MV with +6db subs hot. There was port chuffing but it was not bad. No bad sound was heard at all Again, look at how fast Rythmik puts a brake on the driver. Sorry for the crappy phone video.

https://www.dropbox.com/s/8prrwqwhk0...20hot.MOV?dl=0

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Just for fun, JT. Edge of Tomorrow at reference MV with +6db subs hot. There was port chuffing but it was not bad. No bad sound was heard at all That noise at the end of the clip was not from the sub. Again, look at how fast Rythmik puts a brake on the driver. Sorry for the crappy phone video.

https://www.dropbox.com/s/8prrwqwhk0...20hot.MOV?dl=0
Stupid work has dropbox blocked. I'll have to check it out when I get home.

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Originally Posted by tvuong View Post
Just for fun, JT. Edge of Tomorrow at reference MV with +6db subs hot. There was port chuffing but it was not bad. No bad sound was heard at all That noise at the end of the clip was not from the sub. Again, look at how fast Rythmik puts a brake on the driver. Sorry for the crappy phone video.

https://www.dropbox.com/s/8prrwqwhk0...20hot.MOV?dl=0
Do you have a single or dual FV15HP?

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No wonder I havent heard of them. Im just a poor cheap ignorant audiophile wannabe.
I'll keep them in mind if I win the lottery though.
In terms of technology and engineering, JL Audio has few peers in the industry. A JL Audio subwoofer is designed and manufactured wholly in-house. They make the enclosure, the driver, and the amplifier. They have several patents in subwoofer driver and amplifier design. What ID company can make that claim?

My humble system:

Vizio E601I-A3; Darbee Darblet; Pioneer Elite BDP-62FD universal blu-ray player; Pioneer Elite SC-67 AVR, Dual PSA XS15se's; Monitor Audio Silver RX-6 mains, RX center, and RX surrounds; Home-built HTPC (Xeon E1230, 16gb RAM, Crucial M500 480gb SSD, Radeon R280, Corsair CX600, CoolerMaster mini-ITX case)
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Originally Posted by usaforce87 View Post
In what world is JL high end? They are the automobile equivalent of Bose... some quality, but mostly name brand money scheming.
In an effort to add something helpful to that jeer, The F15 sub to JL 13W7 is like a Maserati compared to a Honda Accord.
What a wildly inaccurate statement. The audiophile equivalent of record-store clerk taste in artists--"if they're big, popular, and successful, they can't possibly be good."

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My humble system:

Vizio E601I-A3; Darbee Darblet; Pioneer Elite BDP-62FD universal blu-ray player; Pioneer Elite SC-67 AVR, Dual PSA XS15se's; Monitor Audio Silver RX-6 mains, RX center, and RX surrounds; Home-built HTPC (Xeon E1230, 16gb RAM, Crucial M500 480gb SSD, Radeon R280, Corsair CX600, CoolerMaster mini-ITX case)
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Do you have a single or dual FV15HP?
Dual.
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In terms of technology and engineering, JL Audio has few peers in the industry. A JL Audio subwoofer is designed and manufactured wholly in-house. They make the enclosure, the driver, and the amplifier. They have several patents in subwoofer driver and amplifier design. What ID company can make that claim?
Impressive. And American...I like that a lot.
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I suppose I could have bought a JL sub if I didn't want to wait for the CA port labor dispute. And then only have 1 sub instead of two, and no laptop or mic to run REW. No thanks. It was worth waiting.

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And a little R&R:
Reaction Audio CX-10 (2)
Rythmik Audio F12 (2)

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post #20186 of 20188 Old Today, 05:35 PM
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How does the F15 compare to a higher end sub like the JL 13 or something of that price range?
JL is a very company with very solid engineering. There area lot of innovations (ie IP) on their drivers. But those are needed to be able to crank up high SPL in a SMALL enclosure using small diameter drivers with long excursion because thermal management (not to fry the driver), maintaining high BL value from a pretty big magnetic gap, and maintaining large excursion without the rubber surround becoming distorted are their top priority issues. So the key is SMALL enclosure, a desirable feature in car audio. If one does that need SMALL enclosures, those innovations are very valuable, a reason why we don’t them in our front speakers.

F15HP is designed with a different design philosophy. Our top priority is fast transient response(meaning low Q and high damping). To achieve that, we need to allow our subs to go down to 14hz with a separate rumble filter control. JL subs pretty much have that rumble filter engaged all the time. A rumble filter always adds ringing to the transient response.


Servo operation addresses another key problem in speakers (not just subwoofers)– memory effect. Memory effect can be explained as follows. If we have 4 notes A, B, C and D with different strength, the reproduced strength of each notes should not depends on the order they play. For instance, the note A strength should not be depend on if it plays as ABCD, DCBA, or DABC…etc. The ideal case that playback does not have memory effect is crucial to all audio gears. Its importance is even higher than distortion. For those who play pianos know not all of our 5 fingers have exactly same strength. A lot of piano practice is to add some compensation so that all 5 fingers appear to have same strength. Other instrument players face the same problem. We certainly don’t want audio gears to add their own memory effects. What are the factors giving arise to the memory effects in subwoofer? First one is the hysteresis of spider/surround of the drivers. Low compliance drivers (those with surround a shard as tires) just make the problem more serious because the spring force now mainly comes from surround/spider than the enclosure itself. The latter is much more linear with very low memory effect. We don’t see stiff surround drivers in our front speaker for a reason. It makes memory effect worse. The second is the voice coil temperature. Thermal behavior in drivers is very complicated. Each note of A, B, C, D leaves a different amount of thermal trace to the voice coil and whatever is played next depends on the history of previously played notes. That is a clear memory effect. There is a surge in high efficiency front speakers on this forum. One of the advantages they offer is they have lower thermal induced memory effect. Between these two sources of memory effect, servo operation reduces the first source by a factor of 3x(or 10db) and completely remove the thermal memory effect. Hope this offers a different perspective to your question.


PS. one may wonder why JL does not offer PR-based subs. Well in one of the CES several years ago, Earthquake wanted to demonstrate their PR-based subs can play 10hz. As soon as they did that, it was very apparent that sub was dancing on the floor and wanted to run away from the scene by itself at the same time. The company representative used his foot to pin that sub to the floor.
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I'll keep them in mind if I win the lottery though.
Pair of Gothams when you win the lottery. Or like 10 F25s.
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Attached a plot comparing two vs. four subs (2 - 200 Hz, 5 dB grid). With four subs I was able to smooth out some room resonance issues, including a dip between 50 and 60 Hz and a big peak up around 120 Hz (sub crossover is set and 70 Hz so that big rise should not be happening; with four subs I was able to suppress and narrow-band it. The subs are hooked up as a mono group but claibrated in pairs. I did fool around with individual settings, but the pairs are symmetric so tweaking them as pairs worked fine. The second rear sub is slaved off the first in the final configuration.

More pictures showing final (for now) system response over on the XMC-1 thread: Emotiva XMC-1 Owners Only Thread I shall note that four subs allowed me to really dial in the overall system response and integration with the mains so I have the best sound I have had in years. Should have added them a while back but other things kept coming up.

I adjusted pre/pro gain so the plots mostly overlie; I did get a large boost in output by adding the rear pair (do not need it, though).

Now of course I wish I had XLR2 amps on my first pair of F12's but everything is working OK as-is. I was worried about ground loops sice the rear subs are on a totally differnt circuit but no problems (whether due to the balanced XLR connections or just luck I could not say). I really like having a trigger input on the subs! Saved me having to get a couple more X10 appliance modules to switch them on and off.

It was a lot of work (had a couple of vacation days I had to take; this used a substantial portion of them) but I am happy with the results. Some sonic issues I've been hearing seem gone now, probably due to a more even sound field and smoother frequency response for the whole system.

Happy, yes I am! Thanks Brian and Enrico! - Don
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"After silence, that which best expresses the inexpressible, is music" - Aldous Huxley
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