Official Rythmik Audio Subwoofer thread - Page 937 - AVS Forum | Home Theater Discussions And Reviews
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post #28081 of 28334 Old 02-26-2017, 11:03 AM
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Quote:
Originally Posted by citsur86 View Post
I completely agree. I'm able to tame a huge peak and get a much nicer overall sound using the MiniDSP 2x4HD. Checkout these sweeps I just did with and without PEQ to prove the point.

Without Smoothing



And with some smoothing:


And that is just using these PEQ filters:


These days I've changed my approach a bit to set target level in the middle (auto set) and cut peaks 50% and boost dips 50%. It allows me to avoid cranking up the sub gain 6-8 dB to compensate for excessive cut only EQ. While overall boost filters can reduce headroom, I listen around -35MV typically, so I'm not worried about clipping as long as max overall boost is 6dB or less. This is helpful since I only have one LFE in, not 2 like you so I don't get that extra 6dB input gain when using the LFE input.

I've also found a mild LF rise from 200Hz to 20Hz helps the high bass ext/damping sound deeper and fuller without making it boomy/muddy (as I still EQ in the 'low' setting).

I look forward to Audyssey XT32 later in the year getting my speakers in the bass region as good as this sub response.



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UN46EH6030 Calibration/Settings
Samsung UN46EH6030; Yamaha HTR-3066, SVS Prime Bookshelf Mains and Prime Center, Cambridge S20 Surrounds, Rythmik LV12R; PS4, Xbox One, Xfinity X1 (CI CXD01ANI)
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post #28082 of 28334 Old 02-26-2017, 11:52 AM
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Originally Posted by primetime74 View Post
Is it best to use the AVR to add boost, or just turn up the gain on the sub while keeping the AVR set up at 0 or below?
Use AVR. This way you know how hot you are running and can easily back it up. We don't know the db value increasing Rythmik sub by one click on the volume dial.
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post #28083 of 28334 Old 02-27-2017, 12:14 AM
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I have been thinking about getting Rythmik subs for a long time and just pulled the trigger on a F15HP to augment my existing Velodyne DD-15. I do mostly music listening and some HT, but am starting my generational change on my equipment. I have been using an Integra DHC-80.3 with Audyssey Pro. I have found it pretty good - better with than without. It really cleans up the overall sound in my 24 X 16' X 9' room, but it does sound a little processed. I also ordered an Anthem AVM 60 so I hope the move to ARC-2 yields good things. I have only heard positive feedback about it and it handles dual subs really well from what I have heard. I have limited freedom with sub placement due to the fact that my room is our living room. My current thoughts are to place one sub about 1/2 way along the long wall and the other about 2/3 on the short wall. My main goal for the additional sub is a smoother in room response. If anyone has advice on how the Rythmik might fare with the Velodyne (or whether I should just aim to sell the Velodyne and buy another F15HP) or if you have a similar setup, let me know.
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post #28084 of 28334 Old 02-27-2017, 12:06 PM
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Originally Posted by mamsterla View Post
I have been thinking about getting Rythmik subs for a long time and just pulled the trigger on a F15HP to augment my existing Velodyne DD-15. I do mostly music listening and some HT, but am starting my generational change on my equipment. I have been using an Integra DHC-80.3 with Audyssey Pro. I have found it pretty good - better with than without. It really cleans up the overall sound in my 24 X 16' X 9' room, but it does sound a little processed. I also ordered an Anthem AVM 60 so I hope the move to ARC-2 yields good things. I have only heard positive feedback about it and it handles dual subs really well from what I have heard. I have limited freedom with sub placement due to the fact that my room is our living room. My current thoughts are to place one sub about 1/2 way along the long wall and the other about 2/3 on the short wall. My main goal for the additional sub is a smoother in room response. If anyone has advice on how the Rythmik might fare with the Velodyne (or whether I should just aim to sell the Velodyne and buy another F15HP) or if you have a similar setup, let me know.
I used to have a DD15, and switched to Rythmik. I really appreciate Rythmik's configurable high pass filter settings, which go beyond what the DD15 offered. Also, I really appreciate how I could sell my DD15 and buy multiple Rythmik subs with the funds.

After switching to Audyssey XT32, and now Dirac, the DSP in the DD15 was redundant.

Coming from the DD15, I preferred the sealed Rythmiks over the ported ones. Perhaps the Rythmiks sound cleaner. I the DD15 is more powerful than a single F15HP, though.
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post #28085 of 28334 Old 02-27-2017, 12:35 PM
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I have used an velodyne hgs 12 on front wall 1/3rd with 15hp on sidewall 1/3rd
also tried 15hp as end table for couch in room 1/3rd

also tried a ton of other locations. they all worked great once I got the tweaking/calibrating right.

my 1st rew attemp gave me 2x 5db nulls at 30hz and 80hz...I got this figured out via audyssey tweaks mainly manually adjusting sub distance in avr.

you may find 1 rythmik 15hp is enough tho if placed right.

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post #28086 of 28334 Old 02-27-2017, 03:04 PM
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Quote:
Originally Posted by rcohen View Post
I used to have a DD15, and switched to Rythmik. I really appreciate Rythmik's configurable high pass filter settings, which go beyond what the DD15 offered. Also, I really appreciate how I could sell my DD15 and buy multiple Rythmik subs with the funds.

After switching to Audyssey XT32, and now Dirac, the DSP in the DD15 was redundant.

Coming from the DD15, I preferred the sealed Rythmiks over the ported ones. Perhaps the Rythmiks sound cleaner. I the DD15 is more powerful than a single F15HP, though.
I will probably go that route over the next few months. The Anthem is suppose to have a test mode that really helps optimize the sub placement. I think dual F15HP would be ample for me in the long run. I do have the DD15 running some DSP, but the majority is happening in the Integra DHC-80.3 with Audyssey XT32 Pro (I have the pro kit - and really like the results there). I own the box and all the accessories for the Velodyne, so hoping that its sale would cover an F15HP-SE

I am planning to follow the initial Rythmik setup according to the My Generic RYTHMIK PEQ3 Subwoofer Setup Guide (YMMV) that has been shared. I will be letting the AVR do most of the work and will set the filters accordingly.
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post #28087 of 28334 Old 02-28-2017, 10:50 AM
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Does Ascend stock any of the Rythmik subs or do they all ship from Rythmik?

I ask because I have not had much luck connecting with any Rythmik owners in the Southern California area but Ascend is here. I really want to hear a Rythmik sub first hand and I'm wondering if Ascend is an option for an eval?
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post #28088 of 28334 Old 02-28-2017, 11:06 AM
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^^ they had some Rythmik subs (not all) that you can audition last time i checked. Call Ascend to see if they can give you a demo.
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post #28089 of 28334 Old 02-28-2017, 11:21 AM
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if I put 2 separate identical subs next to each other? rythmik 15hps

should i run both outputs from avr? or just use one sub cable and split the signal with a y adapter?

also would it really matter which direction they faced or if they lay on their sides?

just thinking out loud as I am itching to get another sub

Power: Marantz sr7008, NAD C 275Bee x 2, Video: Oppo 103, Samsung 75un6300
Speakers: Focal aria 948, Focal cc900, Klipsch synergy KSF 10.5 Subs: Velodyne HGS 12, VA 1512, Rythmik FV15HP
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post #28090 of 28334 Old 02-28-2017, 11:26 AM
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Quote:
Originally Posted by torii View Post
if I put 2 separate identical subs next to each other? rythmik 15hps

should i run both outputs from avr? or just use one sub cable and split the signal with a y adapter?

also would it really matter which direction they faced or if they lay on their sides?

just thinking out loud as I am itching to get another sub
Why wouldn't you want them separated to counter room modes and smooth FR? You will still gain +6dB on the lower frequencies depending on room dimensions.
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post #28091 of 28334 Old 02-28-2017, 12:05 PM
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Quote:
Originally Posted by torii View Post
if I put 2 separate identical subs next to each other? rythmik 15hps

should i run both outputs from avr? or just use one sub cable and split the signal with a y adapter?

also would it really matter which direction they faced or if they lay on their sides?

just thinking out loud as I am itching to get another sub
Using 2 outputs only helps if they are different distances or different models that have different internal delay/phase.
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post #28092 of 28334 Old 02-28-2017, 01:56 PM
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Quote:
Originally Posted by torii View Post
if I put 2 separate identical subs next to each other? rythmik 15hps

should i run both outputs from avr? or just use one sub cable and split the signal with a y adapter?

also would it really matter which direction they faced or if they lay on their sides?

just thinking out loud as I am itching to get another sub
Just my ill informed opinion, if it were me I would use both my sub outputs as they are separate paths in my AVR and Audyssey would set each one independently. Even though they are side by side their environment in the room is slightly different, at least if you're a bit OCD I've read posts where moving a sub a small distance can make a difference. One is closer to whats to the right of it and visa versa. Might not make any difference at all but as I said, in my case they can be corrected independently so why not

Also the gain/output may not be exactly the same for both subs at the same knob position, but again, maybe not significant but knowing me I'd be wondering or have to buy measurement equipment to verify.

If the dual sub output is connected internally in the AVR then which is more convenient and or cheaper; 2 cables or 1 cable and the adaptor...

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post #28093 of 28334 Old 02-28-2017, 05:30 PM
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This is a promo pic I found of FV25HP


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post #28094 of 28334 Old 02-28-2017, 05:38 PM
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This is a promo pic I found of FV25HP




My Current "Living Room" Home Theater!
Plasma 50" TV: Samsung PN50C8000 — DLP Projector: Optoma GT1080
Projector Screen: Elite VMAX2 Electric — Receiver:Pioneer Elite VSX-44 — Fronts: B&W 684 S1
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post #28095 of 28334 Old 02-28-2017, 06:24 PM
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I'd love two of those on each side of my fronts with my FV15hp behind me
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I'd love two of those on each side of my fronts with my FV15hp behind me
Just do it!
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post #28097 of 28334 Old 02-28-2017, 07:48 PM
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This is a promo pic I found of FV25HP
I thought you said 'Porno' pic....lol.
Look gorgeous. Must resist, must resist, I don't need more than what I have now...
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post #28098 of 28334 Old 02-28-2017, 07:52 PM
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Just do it!
lmao, no money or space i just turned 26 and I'm running on fumes

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post #28099 of 28334 Old 02-28-2017, 10:17 PM
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Quote:
Originally Posted by Marc Alexander View Post
Does Ascend stock any of the Rythmik subs or do they all ship from Rythmik?

I ask because I have not had much luck connecting with any Rythmik owners in the Southern California area but Ascend is here. I really want to hear a Rythmik sub first hand and I'm wondering if Ascend is an option for an eval?
Last time I was there (a month ago) they had f12 in their listening room.

My setup is not ideal but you are welcome over anytime.

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post #28100 of 28334 Old 03-01-2017, 01:47 PM
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Originally Posted by chucky7 View Post
This is a promo pic I found of FV25HP

This picture is from our FV25HP prototype so it's not the final product. Our dealer in China (Yosemine Audio) borrowed the prototype to show it in an audio show back in December 2016.

Here is the link:

http://www.yosemine.com.cn/article-241-1.html

Like Brian mentioned before, we have the enclosures and drivers already here in Austin. Just waiting for the amplifiers to be ready.



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Media Room: Ascend Acoustics Sierra Towers w/ RAAL, Horizon w/ RAAL & Sierra 2s | Rythmik F12SE (x2) | Marantz SR7008 | Parasound Halo P5 | Emotiva XPA-3 & XPA-200 | Oppo 105D | Sony HW40ES |
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post #28101 of 28334 Old 03-01-2017, 01:55 PM
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This picture is from our FV25HP prototype so it's not the final product. Our dealer in China (Yosemine Audio) borrowed the prototype to show it in an audio show back in December 2016.

Here is the link:

http://www.yosemine.com.cn/article-241-1.html

Like Brian mentioned before, we have the enclosures and drivers already here in Austin. Just waiting for the amplifiers to be ready.
Yes. The link is where I cropped the picture.

Hey, it still looks awesome, and I'm sure many here would agree.

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post #28102 of 28334 Old 03-01-2017, 03:22 PM
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Yes. The link is where I cropped the picture.

Hey, it still looks awesome, and I'm sure many here would agree.
I've seen the shipping carton in person...the shipping carton size is awe inspiring!

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I currently have a Paradigm Servo 15 v1. How do you guys think this would compare to a Rythmik F15HP or a F18HP?
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post #28104 of 28334 Old 03-01-2017, 10:23 PM
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Originally Posted by chucky7 View Post
This is a promo pic I found of FV25HP

Damn that's a looker 👍
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post #28105 of 28334 Old 03-02-2017, 01:46 AM
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That sub is just insane!
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post #28106 of 28334 Old 03-02-2017, 01:49 AM
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Where did you get this info?
At minimum, Rythmik has said that the phase is a digital delay.
I'm not certain about the rest, but considering there is a digital circuit, it makes sense to use it.
Sorry rchoen not to have posted this reply earlier, but have been quite busy. I saw that Enrico already clarified, but did not need to ask, just looked at the plate of the PEQ3. There is no digital processing going on in there.
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post #28107 of 28334 Old 03-02-2017, 01:55 AM
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What I would like to know from Brian is how much the servo design he has implemented in the Rythmik subs can actually compensate for thermal compression.
Although I agree with most of his statements about DSP versus servo, there is a way to compensate for thermal (or memory effect as Brian likes to call it) with DSP and some producers do implement a thermal control to work with the DSP (Revel for one).

Moreover, if the servo used in the Rythmik had all the benefits claimed, I do not see way we would need a limiter switch. The servo circuit could simply act as a limiter as well.
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post #28108 of 28334 Old 03-02-2017, 05:58 AM
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Read the patent. Analog servo can compensate for voice coil heating; just need the right sensor (a second VC loop works nicely). And I can point to plenty of examples of feedback circuits that go unstable when the circuit is overdriven; at some point, when the output no longer follows the input, the feedback circuit will simply rail at its limits (best case), oscillate, or worse (some, primarily older, circuits would actually invert their output under those conditions and then "motorboat" rail-to-rail). A limiter is complementary to the feedback circuit and keeps everything working nicely.

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post #28109 of 28334 Old 03-02-2017, 06:02 AM
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Quote:
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What I would like to know from Brian is how much the servo design he has implemented in the Rythmik subs can actually compensate for thermal compression.
Although I agree with most of his statements about DSP versus servo, there is a way to compensate for thermal (or memory effect as Brian likes to call it) with DSP and some producers do implement a thermal control to work with the DSP (Revel for one).
Servo is based on remote sensing. So the DCR of the driver is not even in the close-form equation that determines the output. So the compensation is instantaneous and its compensation range is determined by the loop gain. On the other hand, DSP adjustment is at specific time instances or intervals (for instance every second). In addition, it is a "control" meaning it has to know what the resistance of voice coil is before it can control. In the servo, there is no need to know the DCR. So the DSP control loop is: measure -> control -> measure -> control -> measure -> control.... In servo, it is ...............................

Quote:
Moreover, if the servo used in the Rythmik had all the benefits claimed, I do not see way we would need a limiter switch. The servo circuit could simply act as a limiter as well.
Servo does not know if the driver or amp is at its limit.


BTW, Enrico quoted me for a comment that I made a few years back. I'd like to explain a bit more. The unit-to-unit variations are about T/S parameter variations. Very often we take the T/S parameters off the manufacturer's website and think those apply to all units. But in reality as many have done it before, if someone buys 4 units of the same driver model and measures the T/S paremeters, he actually gets 4 sets of different T/S parameters and each set changes over time and changes between small signal vs large signal. Thilo (TC Sounds) told me a story that he delivered drivers to one of his customers and customer rejected those drivers based on T/S paramets out of spec. It turns out, the difference is due to the fact that they measured at different signal levels. After that, Thilo measure parameters at the signal level specified by the customer.



Now back to the "thermal memory" effect. Here is a plot that I use to study thermal memory in non-servo subs. Here I use "two signal levels" to simplify discussion so that we can see output changes much easier. In real world, the signal level is constantly changing. As you can see the output of the large signal is gradually decreasing due to temperature rise in voice coil in what I call "heat-up" period. After we switch to the small signal, at about 3.1sec, the opposite happens that the output gradually increases, in what I call "cool-down" period. We call it memory effect because it is not repeatable. If we run a waveform like above in a round robin fashion, the output of the large signal is different with each repetition because the cool-down period may not be sufficient to bring it back to room temperature. If we take the correlation of the output variation vs the input signal, it is a delayed correlation as temperatutre change takes time to build up and go away. For instance at the moment when the signal changes from large to small, does it go back to room temperature? No it does not. In fact, at that very moment (3.1S), it has the largest temperature variation. But where is the center of the large signal? It is at 2.8S which is the center of the large signal period. That is why I called it memory effect. It is not just a static thermal compression. The folks with DSP say they solve the problem. But in fact, they misunderstand the problem.
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Last edited by Rythmik; 03-02-2017 at 10:32 AM.
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post #28110 of 28334 Old 03-02-2017, 06:42 AM
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Originally Posted by Norixone View Post
Sorry rchoen not to have posted this reply earlier, but have been quite busy. I saw that Enrico already clarified, but did not need to ask, just looked at the plate of the PEQ3. There is no digital processing going on in there.
Yes, I officially concede.
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