Subwoofers with servos.

[Good4it]

They "better" or just different? Are servo subs better sounding?

 

[lovinthehd]

I had (have really, but not used for a long time due damaged cone) an Infinity servo sub, really didn't notice any significant difference moving to non-servo subs after that. Many fans of Rythmik say there's a difference "for music". Then many people say that about a variety of amps, dacs and speakers, too and I don't notice a difference of good or better performance in the subset of music particularly, when compared to audio in general. YMMV as usual in things audio...

 

[AcuDefTechGuy]

Just different technology. They sound just as good as any other good sub.

 

[j_garcia]

Well designed sub is a well designed sub. I think there are some benefits that perhaps don't have a significant enough affect on the sound, but I've owned servo and non-servo and they both sound fine to me too.

 

[roadwarrior]

I just bought a Rythmik sub a few days ago and I've never owned a servo sub in my life before so I'm no "Rythmik fanboy." I own dual ported 12 inch matching subs currently as well and there is nothing BUT a difference in the sound this Rythmik is making with my content so with all due respect I don't really know what these other posters are referring to as "similar sounding servo subs" but it darn sure isn't a Rythmik they are talking about. It's day and night difference for the better.

Brian Ding (the owner of Rythmik in Austin, Texas) owns multiple patents on his Direct Servo design and has a PHD in electrical engineering from USC. Most of his subs offer built in PEQ's and or a 12/24 db low pass filter slope switch for 2 channel listening or home theater as well as a bass extension switch with 3 different dampening modes that basically makes one sub capable of sounding like 3 differently tuned subs and that's before you even get to the Direct Servo part . I should have bought one years ago.

Also his subs just recently were used by a mastering studio in California to master the soundtracks of several recent Hollywood films( Creed being one) as well and they are ordering more of them for their studio they liked them so well. There is a difference with his servo subs I can tell you that much.

Sent from my 710C using Tapatalk
EDIT: the rest of the list of movies/video games mastered on Rythmik subs.


"As I mentioned before Chris Fogel, from Hyperion Sound @ ELBO Studios in Glendale, CA got an FV15HP back in June 2015 for his film mastering studio. Today we got a second order from him for a pair of F12s for a small stereo room. He is very impressed with the capabilities of the FV15HP. So I just wanted to share with you guys the list of the movies he already mastered using the FV15HP:

Creed
Spy
Trumbo
Zoolander 2
5th Wave
Ghostbusters (still in production)
Birth of a Nation (just won Sundance)
Halo 5 soundtrack (game)"


And read this great article by the highly respected sub and speaker reviewer Jim Wilson on the Rythmik LV12R from a few years back and tell me if it gives the impression that a Rythmik sounds just like any other bass reflex subwoofer on the market. Great review by the way.


http://www.hometheatershack.com/forums/speaker-subwoofer-reviews/67309-rythmik-lv12r-subwoofer-review.html

 

[JohnnieB]

I own dual ported 12 inch matching subs nothing BUT a difference in the sound this Rythmik is making with my content

What subs were you running proir to the Rythmiks?

 

[roadwarrior]

What subs were you running proir to the Rythmiks?

Dual BIC PL-200's (still have them but I've got them up for sale locally in Dallas.) They were a good buy for the money at the time. I wanted dual subs but didn't want to spend a grand or so to get them so I went with 2 good midline subs.

Then I got the money together to get one very good ID sub and after lots of research I went with the Rythmik LV12R . Bonus is I'm supporting an in state company but obviously the product had to pass my research first and I'm glad I chose a servo sub.

Have to admit I was a bit nervous having never even heard one before but once I got it placed and I learned how to dial in the settings on the back (no PEQ but a 12/24 db LPF switch and a LOW/MED/HIGH extension switch) I was grinning ear to ear after watching my go to Blu Rays . Highly recommend Dr. Brian Ding's subs (owner and designer of Rythmik subs.)

-Tom

Sent from my 710C using Tapatalk

 

[rojo]

@roadwarrior That's an apples-to-oranges comparison if I've ever seen one. Your argument is specious. Compare the Rythmik to a Hsu VTF3 and you'd have a more difficult time telling the difference. You're right about one thing, though. You should've upgraded from those BIC subs years ago.

Nothing against Rythmik subs, though. They are quite good. It's just that you can't compare an Acura TL to a Hyundai Sonata based on both being sedans and having four wheels. Compare an Acura TL to a Lexus IS instead.

 

[fuzz092888]

@roadwarrior That's an apples-to-oranges comparison if I've ever seen one. Your argument is specious. Compare the Rythmik to a Hsu VTF3 and you'd have a more difficult time telling the difference. You're right about one thing, though. You should've upgraded from those BIC subs years ago.

Nothing against Rythmik subs, though. They are quite good. It's just that you can't compare an Acura TL to a Hyundai Sonata based on both being sedans and having four wheels. Compare an Acura TL to a Lexus IS instead.

TheJman did a nice review comparing an SVS and a Rythmik awhile back. He subjectively preferred the Rythmik and I think noted that it was a possibility that the slightly better decay measurement of the Rythmik (possibly due to the servo) is what he was hearing.

 

[rojo]

Just sayin'. Servo / no servo isn't the only deciding factor in damped response. Look at the spectrographs for the Rythmk LV12R as compared to the Dayton Sub-1200. The Dayton, focused on tuning over low extension, is tighter. But both are far better than the BIC PL-200 (where "200" stands for 200ms ring I guess).

 

[BoredSysAdmin]

@roadwarrior Compare an Acura TLX to a Infinity Q50 instead.

FTFY

 

[shadyJ]

Just sayin'. Servo / no servo isn't the only deciding factor in damped response. Look at the spectrographs for the Rythmk LV12R as compared to the Dayton Sub-1200. The Dayton, focused on tuning over low extension, is tighter. But both are far better than the BIC PL-200 (where "200" stands for 200ms ring I guess).

I don't think you are interpreting those graphs quite right. They aren't really comparable. The PL200 decay isn't that bad. That ringing is over 30 dB down from the initial signal. Also, are you sure those spectrographs are only measuring stored energy? I am not so sure, and I would not try to read too much into them.

 

[roadwarrior]

@roadwarrior That's an apples-to-oranges comparison if I've ever seen one. Your argument is specious. Compare the Rythmik to a Hsu VTF3 and you'd have a more difficult time telling the difference. You're right about one thing, though. You should've upgraded from those BIC subs years ago.

Nothing against Rythmik subs, though. They are quite good. It's just that you can't compare an Acura TL to a Hyundai Sonata based on both being sedans and having four wheels. Compare an Acura TL to a Lexus IS instead.

First off I never said I owned those sub's for any length of time referring to your " I was right about one thing" comment (one less than a year and the other only a few months) so that smartass comment that "I should have gotten rid of them years ago," if acted upon would ACTUALLY defy the laws of physics but thanks for assuming I can time travel. That would be sweet !

Secondly , you should read Audioholic's 2014 bassaholic's rating chart(PDF) on the PL-200 where it receives Gene's Medium size room bassaholic's ratings. Also if I'm not mistaken Dr. HSU himself , whom I admire greatly, had a hand in designing the BIC PL-200 as well as the BIC F-12 so you should probably take the BIC PL-200's excessive "ringing" issue up with him and not me . ( I know it's not an ID quality sub. I never said or implied otherwise.)

Dr. HSU in my mind is also a genius and if I hadn't bought a Rythmik LV12R I was going to buy a VTF-2 MK4 so I get that his sub's with his variable tuned frequency design would be a better listening comparison but I was just making a statement about my recent listening not a broader statement that it was the main reason for any differences. That was your inference not mine.

The main reasons for the differences (which was the majority of my post which you neglected to copy paste when quoting me I notice.) don't have anything to do with any comparison to my BIC and were all well researched by myself before I ever even heard a Rythmik sub trust me.

You also seemed to get from my "nothing BUT a difference " statement that If I had listened to sub's other than the ones I owned and had I been referring to these other (ID subs) that there would then no longer be any measurable difference which is also incorrect . Specs show Rythmik subs all have either just a standalone -2 or -3 db frequency rating along with the +3-3 db rating that is used industry wide. Many other manufactures sealed subs cannot even claim they have 20 Hz extension without this +-3db spec in place. Then you have the memory effect and thermal management (specifically regulating the voice coil temperature) which Brian's sub design also addresses and is borne out in the "repeat" FR test charts done on data-bass(the "repeat" FR tests on the HSU are not the same while the repeat FR tests on the Rythmik are the same due to Direct Servo and it's thermal mgmt.)

His sub's have output based on the FV15HP's extreme room bassaholic rating. They have extension based on his sealed F12's 14-200 Hz (-2db @14Hz) frequency response( NOT +-3db mind you) and they have precision based on my previous post referring to a mastering studios use of Brian's subs . By the way they've ordered 2 more . None of this has anything to do with listening to my "ringing" BIC's by the way.

I've also owned and listened to other sub's (funny you mention Dayton.) So what's the point ? Because I've never owned a HSU specifically I'm disqualified from giving a general comparison between my last sub and my current sub just because according to you my last sub blows ? To me that argument is the definition of specious not mine.

Simple Definition of specious

: falsely appearing to be fair, just, or right : appearing to be true but actually false

The question was "is there a difference with a servo sub?" I felt like commenting because of the extensive research I had done before purchasing a new sub and the fact that I also currently owned a ported bass reflex sub and wouldn't be labeled as a quote/unquote Rythmik fanboy . That's it . I'm not saying non servo subs are worse than Brian's sub's (I'd love to own a HSU VTF-3 MK5!) I'm just saying there is a difference and to say otherwise is to ignore the science not my anecdotal BIC reference.



Sent from my 710C using Tapatalk

 

[rojo]

@roadwarrior You mean you can't time travel? Well there goes your credibility. Psh. Who *doesn't* time travel these days?



Maybe the tone of my post was a bit too confrontational. I'm sorry about that. Enjoy your LV12R. It is a very nice sub.

 

[roadwarrior]

@roadwarrior You mean you can't time travel? Well there goes your credibility. Psh. Who *doesn't* time travel these days?



Maybe the tone of my post was a bit too confrontational. I'm sorry about that. Enjoy your LV12R. It is a very nice sub.

Thank you for that but no apology necessary. I'll give you one though. I've been behind my refrigerator fixing a water leak most of the day today with a flashlight on my head so I probably could have read/responded to your response at a better time but you do have a point ( comparative frame of reference wise) and that was a fair one to make I think.

The great thing about all of this is that there are so many great sub companies (HSU,SVS,PSA, Outlaw, RA,JTR, Rythmik. etc...,) out there that keep their standards so high that we seem to be living in a proverbial "Renaissance age" in regards to great low frequency reproduction. I just wish my wallet was bigger and also my space so I could have one of each !

I am enjoying it thank you and I hope your enjoying yours as well because in the end that's what it's all about.

P.S. If I could really time travel though the first thing I would do other than write the winning lottery numbers on my palm and/or change my major in college would be to have bought a single quality ID sub to begin with and not tried to be "cute" and get lesser dual subs instead. Lesson learned and the next step is to fill that open spot across from my mid wall with another ID sub. Again lesson learned. The hard way. Of course ! Good talking to you and I hope we do again. ( I love Audioholics.com.)

-Tom

Sent from my 710C using Tapatalk

 

[Steve81]

TheJman did a nice review comparing an SVS and a Rythmik awhile back. He subjectively preferred the Rythmik and I think noted that it was a possibility that the slightly better decay measurement of the Rythmik (possibly due to the servo) is what he was hearing.

Jim compared the SVS SB13U to the Rythmik E15, and slightly preferred the E15. I spoke with him about it a bit, and IIRC that preference largely boiled down to the Q-control function on the E15, which allows users to adjust the low-end extension/roll-off to preference. Of course he also subsequently did a review on the JTR S1 and purchased it, so I'm not sure if the Rythmik is still in the picture.

They "better" or just different? Are servo subs better sounding?

A servo does offer some modest advantages. It can serve to lower distortion a bit, and it also helps to control compression so long as the amp still has some power in reserve (though it can't do anything about port compression). That said, it always comes down to the sum of the parts, and servo subs aren't the only ones that excel in those areas.

 

[Irvrobinson]

In Josh Ricci's review of the Velodyne DD18 Plus he measures the sub with the max and min settings of the servo correction level (it is adjustable), and more servo correction significantly flattens and extends the sub's frequency response and reduces distortion.

https://www.audioholics.com/subwoofer-reviews/digital-drive-plus-18

 

[Tim_Saxton]

I've always looked at servo as a way to achieve "extra" performance, read: "control", for a modest price increase, allowing a more modestly designed driver to compete with a bit higher end driver...it's a beneficial technology that when implemented correctly, gets you advantages over competitors at competing price points. But I've not looked at it as a staggering progression of technology or anything. A superb high end driver will have none of the issues a servo is used to correct...Funk Audio TSAD21-V2 comes to mind. Apples to oranges, but a blunt force example of my clumsy point.

That said. I certainly like the Servo products that are available.

Sent from my iPad using Tapatalk

 

[slipperybidness]

I just bought a Rythmik sub a few days ago and I've never owned a servo sub in my life before so I'm no "Rythmik fanboy." I own dual ported 12 inch matching subs currently as well and there is nothing BUT a difference in the sound this Rythmik is making with my content so with all due respect I don't really know what these other posters are referring to as "similar sounding servo subs" but it darn sure isn't a Rythmik they are talking about. It's day and night difference for the better.

Brian Ding (the owner of Rythmik in Austin, Texas) owns multiple patents on his Direct Servo design and has a PHD in electrical engineering from USC. Most of his subs offer built in PEQ's and or a 12/24 db low pass filter slope switch for 2 channel listening or home theater as well as a bass extension switch with 3 different dampening modes that basically makes one sub capable of sounding like 3 differently tuned subs and that's before you even get to the Direct Servo part . I should have bought one years ago.

Also his subs just recently were used by a mastering studio in California to master the soundtracks of several recent Hollywood films( Creed being one) as well and they are ordering more of them for their studio they liked them so well. There is a difference with his servo subs I can tell you that much.

Sent from my 710C using Tapatalk
EDIT: the rest of the list of movies/video games mastered on Rythmik subs.


"As I mentioned before Chris Fogel, from Hyperion Sound @ ELBO Studios in Glendale, CA got an FV15HP back in June 2015 for his film mastering studio. Today we got a second order from him for a pair of F12s for a small stereo room. He is very impressed with the capabilities of the FV15HP. So I just wanted to share with you guys the list of the movies he already mastered using the FV15HP:

Creed
Spy
Trumbo
Zoolander 2
5th Wave
Ghostbusters (still in production)
Birth of a Nation (just won Sundance)
Halo 5 soundtrack (game)"


And read this great article by the highly respected sub and speaker reviewer Jim Wilson on the Rythmik LV12R from a few years back and tell me if it gives the impression that a Rythmik sounds just like any other bass reflex subwoofer on the market. Great review by the way.


http://www.hometheatershack.com/forums/speaker-subwoofer-reviews/67309-rythmik-lv12r-subwoofer-review.html

I spoke with Brian face to face for about an hour when I picked up my F15HP. A good guy and very passionate about the hobby--even though it is his business. No doubts, he knows exactly what he is doing and he does it very well!

On a side note, I did ask what brand of speakers he runs in his personal HT. I doubt that anyone would be surprised to learn that he runs Ascends.

 

[ematthews]

I spoke with Brian face to face for about an hour when I picked up my F15HP. A good guy and very passionate about the hobby--even though it is his business. No doubts, he knows exactly what he is doing and he does it very well!

On a side note, I did ask what brand of speakers he runs in his personal HT. I doubt that anyone would be surprised to learn that he runs Ascends.

RAAL towers are fantastic!!!!!