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#1 ·
 http://www.rythmikaudio.com/index.html


There never seems to be an 'Official' Rythmik thread so....


Hopefully members can post here and representatives from Rythmik (Brian) can more readily answer questions that are normally strewn about in many threads.


Rythmik now offers complete subwoofers as well as the traditional kits.


Maybe Brian will subscribe.
 
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#26,841 ·
I just bought the F12SE, I still have the old Velodyne VA-1210. I wonder would it work to do dual sub one on the left and one on the right. Would the Velodyne hurt the base sound as it's a few generations older......it's a dinosaur. I don't even know what features are in the Velodyne other than having a 10" speaker, a class D amp, adjustable lowpass filter, a 180deg phase switch and a volume control.

I expect the F12SE will sound miles better, I don't want the Velodyne to contaminate the sound.
 
#26,842 ·
So, in a nutshell, this is why Rythmik subs sound as good as they do?

Does high damping further reduce unwanted cone movement over low damping? Is that why they sound so different?

If we are into this type of detail, we can further differentiate the "low damping" sound that is intrinsic to a non-servo system vs "high damping" sound that is intrinsic to servo but eletrically "equalized" to "low damping" (ie, more ringing). The subtle difference is the former has low damping sound because its damping force is low. That means when external force hit the cone, the cone will response with a "low damping" high ringing type of transient reponse. The latter however is different. The external force in servo will respond with a "high damping" low ring transient response. The low damping/high ringing only applies to the signal source. That is why there is a difference between acoustically implemented "low damping" and electronically implemented "low damping" and they sound differently even though in impluse response, they measure almost the same. The disturbance from the external force will show up in measurement microphone response like random noise and it is difficult to separate that from true background noise. One thing is remember is noise and distortion is separated by a vague line. Noise strongly correlated to source signal IS distortion. Distortion after fully randomized so there is no correlation to source signal will become noise. But that is another topic.
 
#26,843 · (Edited)
You can if its over 10%...however we need to consider those tests are done with sine waves and burst tones. They are much more taxing then even the most demanding electronic bass music. A 50hz compression sweep will turn 100% dut and melt a voice coil fast...the only point of that test is to see if the OEM did their home work correctly and employed the correct protection circuits. The most demanding material never exceeds 25% dut. Now when we place the sub's in room, distortion wi go down due to boundary reinforcement upping the efficiency which allows more output with less excursion = lower distortion.

That being said I was just making a point that the Rythmik is far from the cleanest sub from a distortion standpoint when outdoor burst testing @ data-bass, but has always been held with high regards for how good it sounds. That tells me what is being measured outdoors needs to be looked at carefully because it does not translate into the same experience you will get in room.

ShadyJ and I argued over this all the time because he always tried to use those certain Databass measurements to nit pick a sub.

Moral of the story, do not go to data-bass and try to read a few graphs and think you know everything about how the sub will perform. Its not that easy and half of that information needs to be taken as a grain of salt unless you truly understand the data JR is putting out there.

Rythmik makes a great product that uses Servo as one of their technologies to make a solid product. It is not magical and you can still achieve great results with other methods. Just clarifying this because you always hear "It's Servo" and I truly believe 95% of those people do not even fully understand what that means. ;)

Back to original programming....

Any word on the new FV18 and 25?
So it is our job to make customer understand the benefit of servo. Servo can detect the movement of cone and apply the opposite polarity of voltage to the driver (being a close-loop feedback system) to counteract the external force and therefore reduces the amount of cone movement by a factor of 3x. Any unwanted cone movement generates sound. Imagine when the acoustic energy hits the enclosure and cone. The enclosure wall remains sturdy, but the cone is relatively free to move. The cone generates sound when it moves. The ability to reduce unwanted cone movement is one of the key benefits of servo. I was in the factory to demonstrate how to test our servo amps by displaying the amplifier output on the oscilloscope. A few bays over, another team is testing another design using music signal. My display showed so much noise that I had to ask them to stop in order to show a clear waveform. This is to show you how servo rejects noise that is not in the source and the ability is present anytime the amp is on. This noise can come from another channel, it can also come from the standing wave inside the enclosure itself. In terms of the force used by our servo to counteract cone movement, it is damping force, not inertia force, not spring force. The insertia force and spring force (exhibited from other type of servo designs) actually store energy and then release it back via cone movement. Our damping force method dissipates energy as it counteract cone movement. It acheives a much better clarity.
If we are into this type of detail, we can further differentiate the "low damping" sound that is intrinsic to a non-servo system vs "high damping" sound that is intrinsic to servo but eletrically "equalized" to "low damping" (ie, more ringing). The subtle difference is the former has low damping sound because its damping force is low. That means when external force hit the cone, the cone will response with a "low damping" high ringing type of transient reponse. The latter however is different. The external force in servo will respond with a "high damping" low ring transient response. The low damping/high ringing only applies to the signal source. That is why there is a difference between acoustically implemented "low damping" and electronically implemented "low damping" and they sound differently even though in impluse response, they measure almost the same. The disturbance from the external force will show up in measurement microphone response like random noise and it is difficult to separate that from true background noise. One thing is remember is noise and distortion is separated by a vague line. Noise strongly correlated to source signal IS distortion. Distortion after fully randomized so there is no correlation to source signal will become noise. But that is another topic.

This is very interesting. I read from other threads that "servo" is just marketing yet I do believe my FVX15 sounds tighter than the MFW-15 I had before. How do you quantify that? As far as output goes, I agree other subs can have similar output as Rythmik subs using different methods, but does 110db @ 20hz or 110db @ 50hz, sound the same on all subs? I am sure distortion plays a part of the sound equation, but I also think that servo sounds better. It is harder for me to tell to tell that difference in a movie such as Mad Max Fury Road, but it seems easier to hear with music (Steely Dan, Flim & BB's, Metallica, Kraftwerk, etc...). I am no expert by any means, have not heard every sub out there, and am a huge skeptic when it comes to marketing BS, but I do think the reviews/feedback from people who buy these subs usually are pretty consistent (tight, punchy, articulate). Some people even say output is less than other subs because they are used to loud bass not clean bass. I have a music listening friend who went from a Klipsch sub to an L12 and is amazed at how much better it sounds. So if I am sold on marketing, so be it! Time to go watch a movie! :D

Btw, I can't wait to hear feedback on the FV25 & FV18!
 
#26,844 ·
Here they are: FV25HP and FV18 final prototypes going into full production. I will post more info and specifications as soon I get green light from Brian :) Or maybe he will post that info... :D




I'm sorry but after looking at these two beauties do you all need some alone time, or is it just me? I have the FV15HP but would love to expand my sub ownership to include two of these beauties. Ahhhhhh........someday.

Regards,

RTROSE
 
#26,845 ·
So it is our job to make customer understand the benefit of servo. Servo can detect the movement of cone and apply the opposite polarity of voltage to the driver (being a close-loop feedback system) to counteract the external force and therefore reduces the amount of cone movement by a factor of 3x. Any unwanted cone movement generates sound. Imagine when the acoustic energy hits the enclosure and cone. The enclosure wall remains sturdy, but the cone is relatively free to move. The cone generates sound when it moves. The ability to reduce unwanted cone movement is one of the key benefits of servo. I was in the factory to demonstrate how to test our servo amps by displaying the amplifier output on the oscilloscope. A few bays over, another team is testing another design using music signal. My display showed so much noise that I had to ask them to stop in order to show a clear waveform. This is to show you how servo rejects noise that is not in the source and the ability is present anytime the amp is on. This noise can come from another channel, it can also come from the standing wave inside the enclosure itself. In terms of the force used by our servo to counteract cone movement, it is damping force, not inertia force, not spring force. The insertia force and spring force (exhibited from other type of servo designs) actually store energy and then release it back via cone movement. Our damping force method dissipates energy as it counteract cone movement. It acheives a much better clarity.
Makes sense and I can see the point but is that really audible in a real world listening session with source material? Similar to how the FV15HP shows higher distortion during data-bass testing compared to some other sub's, but does not seem to be a issue in room.
 
#26,846 ·
I'm thinking that in a multi-sub environment, servo helps to mitigate acoustic coupling among subs in the same room. Same goes for acoustic coupling between the room and the sub itself.

However, in the big scheme of things (room modes, acoustic interactions, stuff rattling), servo improvements gets drowned out by them as well as sensory overload in HT.

I just believe the benefits of servo gets overshadowed by other deficiencies in the room. However, in a properly setup room with no other sources of noise and distortion, servo does improve bass decay caused by room modes and acoustic interactions.
 
#26,850 ·
#26,851 ·
I have a customer just waiting to place order for quad FV25HPs :eek::D



....it'll be a great place to watch a movie, and get your kidney and gall stones pulverized in one night!
 
#26,852 ·
My Thanks to Enrico

I have had several questions answered recently by Enrico. He answered my emails quickly. Today I had the final answers needed and placed an order for the F12 oak finish at 1:42PM. I just received the shipping/delivery notice @ 3:09PM: Scheduled Delivery Date: Friday, 11/04/2016 here in Silicon Valley.

Nice, and thanks again Enrico;)
 
#26,854 ·
I have had several questions answered recently by Enrico. He answered my emails quickly. Today I had the final answers needed and placed an order for the F12 oak finish at 1:42PM. I just received the shipping/delivery notice @ 3:09PM: Scheduled Delivery Date: Friday, 11/04/2016 here in Silicon Valley.

Nice, and thanks again Enrico;)
I just ordered a F12SE with silver cone and my delivery date is Friday also. I am also in Silicon Valley. I can't wait to test it out. I am going to custom order a piece of thick glass and turn it into a very nice looking end table as decoration on top of it's function.
 
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#26,856 ·
There any price ranges yet for the FV25 and the FV18?

i'm going to guess that the single ported 18 will be in the ~1700 range, and the dual 15 ported will be in the low to mid 2's, never-mind shipping. i know the dual 18 jtr cap4000 is $350 shipped, and the fv15hp was $130 when i grabbed it. so probably ~$170? for the 18, and ~$220 for the dual 15? just my personal speculation.
 
#26,859 ·
@enricoclaudio

How much more output will the FV18 and FV25 have over the FV15HP? Sorry I know this has been discussed before, but I don't feel like going through page after page to find the answer. :cool:
i just want to see data-bass get their hands on them and put up the numbers. theories and speculation are just that.
 
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#26,860 ·
Brian is working putting together the info and specifications for the FV18 and FV25HP subwoofers. He is also working on the website links for these two models and they will be up in our website anytime soon. That's all I have to share for now.
 
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