Official Rythmik Audio Subwoofer thread - Page 191

My F12G SE is probably shipping today - can't wait. I feel a sickness coming on and may need to be off on Thursday or Friday

Do you mean Thursday AND Friday. It does take a little time to really appreciate the finer points of a Rythmik subwoofer.

Yep - I work from home so kinda joking about being sick.

So my plan is to set the F12 to default settings - http://forum.ascendacoustics.com/showthread.php?t=4432 and then let my Integra 8.8 run and let Audyssey multi EQ XT do its thing. The other speakers are bookshelf Energy Take Classics. Sound about right?

Wikipedia is a good thing. I looked up audio crossover and it talks about the different orders of filters. Essentially, the higher the order, the steeper the slope.

So it seems reasonable to me still that a freq setting of 14hz with the rumble filter on would essentially never get down to 14hz since the rumble filter would be applying a 3rd order filter at 20hz.

But it's interesting to me that Configuration 2 from the FAQ has this exact thing as an example.

Configuration 1: a sealed box with rumble filter off and extension filter on at 20 Hz has a 2nd order roll-off at 20 Hz.

Configuration 2: for the same sub, if one wants to have a 3rder roll-off to attenuate some subsonic signals, he/she can set the extension filter to 14 Hz med damping and turn on the rumble filter.

Configuration 3: if one set the rumble filter to on and set the extension filter to 20 Hz, then one gets a 5th order roll-off characteristic from this combination.

Are there any good rules of thumb for where to put the freq, damping and rumble filter settings for different types of content? For instance, on the FAQ he states this:

On dance mixes and music with extremely high bass contents, one does not need 14 Hz extension because of what is called the "masking effect". The masking effect occurs when a high amplitude signal is present simultaneously with other smaller amplitude signals. The perceived loudness of the smaller amplitude signal is drastically reduced. In addition, human ear's sensitivity decreases in the lower frequencies. Therefore for this type of music, one may even want to set the extension setting higher with lower damping factor setting (in our A350/A370 amps). That will make the bass sound clean (by removing ambient information) and punchy. It essentially allocates more amplifier power to the signal that we hear and care about most. On the other hand, when no such signals are present (for example, in jazz, solo and other types of music) and masking effect is not strong, one can clearly hear the difference that a 14 Hz extension makes (vs say 28 Hz extension)

I find it interesting that a lower damping would make the bass sound cleaner and more punchy. My limited experience is that the higher the damping the cleaner it seems to sound. I need to go try this out with some dance music and see what it sounds like.

So what do all of you guys have yours set at and why?

Mine is set at 14 hz, high damping. I tried the 14 hz and low damping and to my ears it seems to enhanced the bass notes, which for some music like trance has a better overall effect. I have not tried the other extensions yet, pretty much happy with the performance. Right now I just use the iTUNES eq to boost the bass for those types of music as its more convenient than fiddling with the plate amp controls

Rumble filter off?

I have a single F15 and it fills my room, roughly same size as yours. I guess two F12 or FV12 would be better to even out the response in the room.


Edit ...

take my reco only if your room is 1 feet high, which makes it 2600 cubic feet. :-)

Punchy bass (than what it really should be) is an emphasis in the midbass region. To get that type of sound you need to have 1) higher bass roll-off and 2) low damping. The combination will filter out low rumbling signals more effective so it sounds clean. The actual ring time is roughly related to Q times corner frequency (the actual formula is more complicated than that). High Q (low damping) combined with higher HPF extension filter will mitigate the boomy that you hear with lower HPF extension filter setting (say 14hz). So the overall boominess is acceptable. (The worst boom is low extension combined with high Q / low damping). But if you listen carefully to that type of punchy sound (high roll-off with low Q) when you have a full bandwidth sound reference (14hz high damping), you will notice some detail is filtered out. But for those with full bandwidth reference do not know. They will think the sound is clean (being filtered out more) and punchy (trade off less audible low end signals with more audible mid bass signals) until they come to hear the "reference".

its off, i dont do HT so there no need for it...

Thanks Brian, that was a great explanation of the tradeoffs of each setting.
I did not realize that the HPF affected the midbass sounds at all (causing them to be more emphasized or punchy). I thought it was strictly a setting on how low it goes and for limiting cone excursion at high SPL.

One thing you said confuses me a bit. I equate boominess to be opposite of clean/tight/punchy and my assumption was that higher damping (low Q) always makes it sound cleaner and tighter and less boomy regardless of where the HPF setting is. But from what you are saying HPF combined with low Q (high damping) provides less punch than with low damping. I would have assumed high damping would have sounded cleaner and punchier with less boom.

I think I'll experiment a bit more and see how well I can hear all these differences. I had settled on 14hz with high damping as what I thought sounded cleanest, but always had the rumble filter on. I'm going to try some of these other ones and see what it sounds like. This is the fun part for me. I think my wife wants to kill me now

Thanks again I am really enjoying these subs! And thanks for putting so much control in them to customize to our listening preferences!

Do you really mean 2,600 sq feet? That's massive and the size of most people's entire homes. If that is the case, then no one single sub will ever do, unless you have one in every second room . . .

Or did you mean to type 260 sq feet or 2,600 cubic feet?

For what it's worth I have two F15 subs in a room 21' * 14' * 7' and they're placed to smooth out the overall bass from 4 sources (2subs+2 mains) and provide an upward tilted bass frequency response as freq falls similar to the Equal Loudness curves.

Oops! Sorry for the typo. I meant approx 2600cuft. The room is 22x13x9ft.

I have a question, and I apologize in advance if it's a dumb one: for an E15, the specs show a frequency range of 14 to 90Hz. It starts to roll off at about 70Hz, according to the posted graph. Say my speakers are rated at 60Hz+ and I want to give them a bit of room to breathe by crossing over at 80Hz. Since the E15 starts rolling off at 70, how would all this play out? I've seen other sealed subs going to 200Hz, not that I need it but it was there. Thanks!

^ The roll-off depends upon the crossover setting. Or, if you use the LFE input, the sub will go to somewhere between 150 and 200 Hz (I forget exactly). In any event, you'll have no problem. Crossover above the speakers stated LF corner is a very good idea; not only does it give them "breathing room", but the result is better sound because the sub will generally do the low end with much less distortion than your other speakers. Especially a servo model like Rythmik.

You can use LFE input. I haven't updated the plot for E15. The old plot is measured with line level input at AVR/12 LPF setting. That was 3 years ago. Ever since them we have gone through PEQ2 amp, and now PEQ3 amp. LFE plot is very similar to the LFE plot for F15.

http://www.rythmikaudio.com/F15_specs.html

Thanks DonH50 and Brian!

Cool, I got it!

I will be using the subs in a 2 channel + 7.1 config -preamp with HT bypass. 60% music, 40% movies. Just waiting patiently for the XLR version to arrive, then I'll be joining the happy Rythmic family! I believe for a Master/Slave config I will need the XLR2.

Or an AVR with XT32 and dual sub outputs...

I am using an external crossover between the preamp and amp/sub. I should still go out from the crossover into the LFE input of the sub, correct?

Rumble filter and limiter are on different principles. Rumble filters actually filter out low frequency signal. It is necessary for vented sub because below the tuning frequency, the driver becomes "unloaded" (meaning there is no enclosure back pressure to limit the excursion). So rumble filter is like a guard at the gate checking everyone's ID. But even with that, the club can still be over-crowded. So limiter is like a volume control on the fly that "shrink" the signal when it thinks it is about to go into clipping (like shrink the people in the club so that it can accommodate more). Rumble filter still follow linear operation. Limiter does not. That is the first difference. Second, rumble filter is necessary for vented subs, but not for sealed subs because sealed subs have enclosure back pressure to keep the excursion in check. Third, in sealed subs, one can use rumble filter to conserve energy (or power) so that it can be used on more audible frequency band.

FV15HP vs F15HP: F15HP has better bass extension. But its 20hz output is not as good as FV15HP. It is 10hz max output is roughly 12db down from 20hz and it is 5hz max output is roughly 24db down. On the other hand, FV15HP in 2port mode starts roll off at 18hz. when it reaches 9hz, its max output already about 24db down. At 4.5hz, its output 48db down. 1 port mode improves the output down to 13hz. But below that, its roll-off characteristic is just like 2 port mode. So the lower it goes, the less output it has compared to F15HP. So even though F15HP may start with less output at 20hz, but as the signal moves lower in freuqency, it begins to show its advantage over FV15HP. But the most important part is how you trade-off the two.

Any of the following situation would warrant an FV15HP over F15HP:
1) You are happy with the sound of your current vented sub and just want to improve the tightness and overall realism (vs some customers absolutely don't like vented subs).
2) You prefer more full body sound. You have listened to some sealed subs and they are too lean for your preference.
3) You use the sub for 90% HT. You are not really that critical about the music.
4) You used to have a sealed sub, but the vented sub in your friend's house blows your mind.

Any of following situations would warrant an F15HP over FV15HP:
1) You are happy with the sound of your current sealed sub and just want to improve the extension and overall realism.
2) You like fast, clear, and articulate sound. You don't really play loud and your system seems to have high resolution that you can hear the sound from different components (such as different power amp, CD player, cable, ....).
3) You have a more acute hearing than others. You consider yourself to be a more musical person than average.
4) You are all of the above except you do play loud which will require multiple sealed subs.
5) You used to have a vented sub, but you heard a sealed sub in your friend's house and it blows your mind.

For those still cannot decide, either one will do

Feel free to add as the above is just a general guideline. If we get enough consensus, we will put that on the web.

Thanks for the comparison on the FV15HP and the F15HP. Im still undecided which way im going to go, might just flip a coin Im still leaning towards the F15HP since im not sure i really need the extra db's since i cant really listen at reference level in my townhouse. I always had sealed subs in my cars growing up and preferred their sound as well. The only thing holding me back is that ir seems everybody recommends the FV15HP for home theater use which will be 90% of my use. I dont want to buck the trend

I chose the sealed F15 primarily for majority home theater because I preferred it's sound in music and non LFE bass sounds. The edge in tightness just sounded a bit better to me. I will take better sound over SPL. Now my home theater use is really more of a TV watching one, not many movies. So that went into my decision as well. Think about all the music that also exists in TV and movies!

If I was strictly watching movies that were mixed well with lots of LFE I might have chosen differently. But the F15 really does hit hard and fast. Don't let people tell you otherwise. When watching a movie I can feel like I'm getting punched in the chest and the walls shake. The FV15 was just a bit moreso with the wall shaking.

Well, I am going to buck the trend.
Sure, the general consensus here, at AVS in general and the rest of the interwebs is that for ht/movies go for ported but for music go for sealed. I disagree.
A ported sub will give more output at the tuning frequency of the port(s) compared to a sealed sub (as exemplified by the F15HP vs FV15HP comparo Brian posted above). But look at how the ported subs falls off below the tuning frequency of the ports. It drops like a rock. The "better" lfe movies, much more than music (except maybe organ music), have plenty of material below the 20Hz tuning frequency, many times hitting single digits. A ported sub will lose to a comparable sealed sub in those frequencies every time.
Plus, the ported sub will not be as accurate in the bass reproduction as the sealed will be.
So, yeah, maybe at 20Hz the ported sub will have more impact but at the rest of the frequencies it has to reproduce, it will have less.
FV15HP: http://rythmikaudio.com/FV15HP_specs.html
F15HP: http://www.rythmikaudio.com/F15HP_specs.html

Hello All,

So I just bought a FV15HP about a week ago. I hooked it up and used for a couple days listening to TV with no issues that I could tell as it was a at a low level of listening. Today I tried to play some music (rock) and noticed a slight rattling. At first I thought it might have been coming from my fireplace or something nearby but upon further inspection it was coming from the cone of the subwoofer. I turned up my UMC-1 to level 35 to see if I could hear it better and sure enough it was the cone of the subwoofer that is making a rattling noise. Any ideas what the issue is? I dont see how it could be blown already as I have yet to even try to put it through any testing. Is something like this covered under warranty??? Spending 1500 bucks on a couple days of TV use sure does not make me happy.

http://rythmikaudio.com/contact.html

Good luck getting that resolved. As they say stuff happens, I am sure it will be taken care of but never fun having a new acquisition being less than perfect out the gate.

Best Regards
KvE

Good point. Another point most people fail to consider is the "tuning" of their room. My room is 30'x30', so its fundamental modes are in the 20 Hz range. Audyssey has to significantly attenuate frequencies in this range just to get a reasonably flat response. The last thing I would want is to exacerbate the problem by adding a port with even more output at 20 Hz.

I've had a ported sub in that room, and it sounded AWFUL, so bloated in that 20 Hz range. Now I used a sealed sub (Paradigm Sub 1), and with heavy EQ+good placement, I can get a nearly flat response from 20-80 Hz.

Tell Brian (Rythmik) and I'm sure he will get you fixed up as fast as he can... he is known for his excellent service to the customer. Occasionally stuff happens... my guess would be the sub was probably highly mistreated during the shipping process. Rythmik has one of the best and most responsive service records amoung the ID companies... Brian will work with you to make it right but first you've got to let him know there's a problem, so just give him a call.

Have you peeked inside? It may just be as simple as something shifted back there and its now contacting with the cone during larger excursions.

If you want the crossover to control the sub's crossover frequency without an extra filter in the circuit, yes.

I have not opened it up, I did not want to do anything which might void any warranty

I've been inside my subs to make modifications no less, and all with Brian's blessings... so that's why I'd seriously doubt it would void the warranty but go ahead and contact Brian first... I'm sure the first thing he will ask you to do is take out the 10 or so screws holding the amp in place and take a peek inside.

Do you hear rubbing if you push on the cone with the amplifier off?