Official Rythmik Audio Subwoofer thread - Page 276

Originally Posted by Rythmik 

Corner loaded helps output and it is our first recommended placement.

Originally Posted by Rythmik 

The main reason that you hear very different results with the distance to wall of your Vandersteen is the front speaker has a baffle width related roll off below 200-300hz. Some call this baffle loss which takes place because sound at higher frequency is no longer omni-directional. All speaker designers who know what they are doing will compensate that by boosting the frequency band below 300hz (using voice coil inductance) if they are supposed to be placed off wall. On the other hand, if the speakers are meant to be placed close to wall, the baflle loss will be much less and there shouldn't be much boost below 200-300hz. In short, to get the speakers sound right, you need to learn from the speaker company if they are supposed to be placed close to wall or off wall. Of wall placed front speakers have better image. The reason we have stereo image and sound stage is because wall reflection. The sound played in anechoic room (even if they are in stereo) is very boring. It has nothing resembling what we hear every day. BTW, a lot of members have favored low indutance drivers and forgot about the baffle loss compensation. The resulting sound from a lof of DIY project using low inductance drivers is the mid bass is just lacking, period. This is off topic.

Now sub is different. There is no baffle loss. So place in the corner is ok. The boost from corner loading is supposed to be very uniform. Don't worry about the boomy sound coming from our subs. The reason we hear boomy sound is because some subs do have a very narrow sweet-spot. If you turn the volume low, you don't hear bass, and if you turn the volume up, you hear boomy sound. But our subs address those problems. Once you hear the sound from our subs, you will agree.

Originally Posted by Rythmik 

Every expert has his own blind spot. To give you an example. Dr Klippel is well-known for its speaker test equipments. He can also do spider test. I sent one for him to test and he sent back the report, but there is no test on hysteresis. I asked him for a test like that and he explained there is no hysteresis in spiders. But anyone who can mark the voice coil and observve hysteresis from spider. Pull the cone up and let it return to the resting position and then push the cone down and let it return to the position. These two resting positons are not same. The difference is not much in ours (maybe 1/2 mm). So it does exist.

Now, back to servo. we call our servo direct servo because there is no active design added to the servo feedback. It ensures the most pristine signal quality. It is very different. In addition, the analysis of servo feedback was very ad hoc. There were no theory behind it and often the engineers at that time is just do a bunch of trials-and-errors. But it all changed after our patent. I could have submitted a technical paper to AES. But I didn't bother. I already published what I think enough papers in another field in EE. I didn't care too much in getting my name known in audio and that is the story of our servo design, very humble and yet it is a design advantage that is truly scalable.

Originally Posted by justindo 

Hi all,

I'm considering a Rythmik sub and have a couple questions that I was hoping you could answer for me. Thanks in advance.

First, it seems I've read that the cabinets are sourced from Asia and that the subs are assembled in Austin. Is this true? What about the drivers? Rythmik doesn't seem to mention any of this on their site compared to, for example, PSA.

Second, I'm looking at the F15 and the F15HP. Do you think the latter is worth the extra money? My room is 24x18x8.

Originally Posted by mlundy57 

... But then, if I wanted things rattling off the walls I'd move back to California.

Originally Posted by Cowboys 

^^
Trust me, once you have an FV15HP in your room, you will be asking yourself that you were happy with the smaller sub F12? For me, I had the SVS SB12nsd in my living room and thought it was all I needed, then came the Monster FV15HP for my dedicated theater. I spent a few weeks listening and watching those 5 stars bass movies in my theater and was amazed. One night, I was lazy to go to my theater for a movie, so I fire up one of those 5 stars bass movie in my main living room with the SB12nsd and kept finding myself increasing the volume on my receiver and the LFE trim (10dbs hot) and it was not enough. So I put in a movie that I know it sounded loud and deep with the SB12 before but I was disappointed this time around.

Originally Posted by mlundy57 

I tend to go against the consensus in that I use a single F12 in a room a little larger than yours (20x25x8). The F12 fills my room just fine for me, but then I'm not a bass head either. I like everything to blend with no one part of the spectrum overpowering any other. The F12 does this very well and still has plenty of punch for movie sound effects for me. But then, if I wanted things rattling off the walls I'd move back to California .

Originally Posted by BDP24 

Well the FV15HP oughta give you more than the F12, seeing as how it costs twice as much!

Originally Posted by Rythmik 

This is tricky. Only fire up the sub after the sub is brought to room temperature for over a day (let us be safe). There can be condensation on the eletroncis. Last winter I had a sealed sub delivered to a customer northeast in a big storm. That one was a DOA. I cannot quite figure out the reason. But let us just play safe. If the package was left to freeze outside, broght the sub into the house and unpack it and make sure it is room temperature for sufficient amount of time.

Originally Posted by raaj 

Hey! Don't you guys in OK flatlands get your walls rattled by them twisters too??






(I went to OK State, Stillwater for a sem. Fond memories of that quaint li'l place.)

Originally Posted by dstew100 

OMG if I had to look at my FV15HP for a day or two without hearing it after the dreaming, research, saving, and waiting on UPS I think I'd explode... well, it's better then having to ship around in circles and waiting longer.

Originally Posted by lennyp 

Yes, good advice - I will definitely let it acclimate. No need to cause potential startup issues. Temps look like 40F as a high next week. With any luck, UPS wll be gentle and not leave it without signature. I guess an advantage of internet buying, I don't know what I'll be missing until I finally fire it up, so I will wait a couple days!

Originally Posted by Cowboys 

I am not comparing the two but trying to tell my story that once one heard/owned a better sub, you don't know what you miss.

Originally Posted by lennyp 

Happy to say my FV15HP will be here next Wednesday. Hopefully our expected 30" of snow this weekend won't cause any issues!

Originally Posted by GIXX1300 

Mine is scheduled for delivery on Tuesday. Forecast.. 80 degrees.. I love Florida! :-)