Rythmik FM8

[stunta]

I can't remember if I considered this as an alternative, but the L22 is a larger version of FM8 (no mid-bass option I think) that can also serve as speaker stands given their front-firing ports. Pricing is not all that different but obviously the weight and dimensions are different.

 

[tgray]

Everyone who is using 2 x FM8s as stands/stereo flanking subs still happy with the setup? I'm considering getting a second FM8 and a MiniDSP SHD to do the same...

 

[WillBrink]

Everyone who is using 2 x FM8s as stands/stereo flanking subs still happy with the setup? I'm considering getting a second FM8 and a MiniDSP SHD to do the same...

This thread does need an update! I'm using one FM8 now (me beloved Velodyne HGS 12 died after 20+ years of use) and I like it a lot. I'm limited for space, and the design of the FM8 appealed to me. I'm considering ordering another and using them as a base for my ATC 19v2. Two FM8 costs less than the one Velodyne sub did over 20 years ago.

 

[dwkdnvr]

Everyone who is using 2 x FM8s as stands/stereo flanking subs still happy with the setup? I'm considering getting a second FM8 and a MiniDSP SHD to do the same...

Wow - reviving a stale thread that I'd forgotten about.

I'm still using dual FM8s, although I've moved my R3s to an office/desktop setup and replaced them with LS50 Metas (and added a 3rd Meta as a center). Still very happy with this solution for a space and aesthetically constrained system. (using the SHD to handle xover and EQ duties)

 

[nick-v]

I absolutely loved my pair of FM8's.

I sold them off as my system moved in another direction (more of an all purpose Media Room system with JBL Synthesis speakers & gear). I wouldn't hesitate to buy another pair for a dedicated 2 channel system sometime in the future.

 

[WillBrink]

I absolutely loved my pair of FM8's.

I sold them off as my system moved in another direction (more of an all purpose Media Room system with JBL Synthesis speakers & gear). I wouldn't hesitate to buy another pair for a dedicated 2 channel system sometime in the future.

Did you use them as stands or separate? I have one currently and am happy with it. Now want to hear two of them and would use as stands due to space limitations.

 

[dwkdnvr]

Did you use them as stands or separate? I have one currently and am happy with it. Now want to hear two of them and would use as stands due to space limitations.

I'm running mine as stands, effectively turning the LS50 Metas into 3-way floorstanders. The FM8s + SHD mean I can cross higher than a typical LFE xover would run. I think I'm running at 150Hz which offloads the Kefs.
Certainly not ideal from a 'big iron HT' perspective where people want to run multi subs placed around the room, but it's working very well for my purposes.

 

[WillBrink]

I'm running mine as stands, effectively turning the LS50 Metas into 3-way floorstanders. The FM8s + SHD mean I can cross higher than a typical LFE xover would run. I think I'm running at 150Hz which offloads the Kefs.
Certainly not ideal from a 'big iron HT' perspective where people want to run multi subs placed around the room, but it's working very well for my purposes.

Thanx for the info. I'm using ATC SCM 19v2 as main L/R which are large stand mounts and xover at 80hz as typical using the one FM8. If i get another and use as stands, will likley change that some too.

 

[WillBrink]

Oh, that's not my setup. You might want to ask this @Olli.

But I could give you some general advice:

• Choose a crossover frequency between room modes, i.e., where the subwoofer(s) and the main loudspeakers meet the measurement signal's reference SPL [+/- 0 dB] and use filters that sum to a linear frequency response
• Choose XO as high as possible but not above roughly 100 Hz as otherwise, frequencies get more directional and the subwoofer(s) might become localizable [unless placed next to, or even better, below the main loudspeakers]
• The FM8 is a special case, as it is intended for use up to 250 Hz: this makes sense with main loudspeakers that have relatively small drivers to reproduce the bass region [which extends up to ~300 Hz]. It might result in improved clarity and minimal ringing, once those small drivers got "relieved" through such a relatively high, high pass filter
• Linear phase crossover filters seem to result in best time alignment; preferably those with a steep slope.

As for the Isoacoustic pucks, I would expect they do their job but you could also use every other material that is reasonably thick and dampens vibrations; like some types of rubber mats.

What would you and co recommend? I'm considering such a set up myself. Basic rubber feet? Other? There's all manner of rubber/silicon feet of various sizes via Amazon and such. I was thinking:

Amazon.com

 

[nick-v]

Did you use them as stands or separate? I have one currently and am happy with it. Now want to hear two of them and would use as stands due to space limitations.

I used mine as stands. I did use a decoupling layer between the subwoofers and the speakers, but they were excellent!

 

[windycitycy]

I'm in the process of updating some things in my setup and am wondering if 2 of these Rythmik FM8 subs would provide any benefit used as rear subs in a 7.4.4 setup. I currently have 7.2.4 with an HTP-1 and Buckeye amp ... and have DIRAC DLBC. My room is in flux as new LCRs are on order and 1 of my JL subs is being upgraded from V1 to V2. Front LCR will be full range on-walls 45Hz - 20KHz. Side and Rear Surrounds are fairly full range on-walls 55Hz - 20KHz. Tops are 60Hz - 30KHz. The front 2 subs are JL Audio F113s. I am considering adding 1 or 2 subs to the rear of the room (these need to be smaller in size). Rythmik subs look good .. either 2 of these FM8s, 1 or 2 Rythmik F12SEs, or possibly stay in the JL Audio family with 1 or 2 F110s or E110s. Will adding smaller subs be beneficial?

Things I would consider beneficial:

• Reducing/cancelling room frequency dips and peaks. I've read quite a bit about how 4 subs can cancel each other out. What if 2 of those are larger than the other 2?
• Evenly distributed bass across the room
• Dynamic bass for movies/videos
• Properly timed/phased bass for music

 

[WillBrink]

My current set up, using 2xFM8's. Put high density foam between them ("Sound Addicted - Studio Monitor Isolation Pads") and I assume that's adequate vs say IsoAcoustics products which can add costs quickly. Thoughts/opinions there?

I found dual mono setting on base management was preferable to stereo subs to my ears, so leaving the setting as dual mono. Having ARC Genesis and base management via the Anthem integrated makes it much easier to set up/blend for me. As one can see, limited in space and must follow WAF on that one, so the FM8's checked off all boxes there. They're almost exactly the dimensions of the stands I was using, and had one sub in the corner, now I'm finally doing dual subs. I have never tweaked the ARC settings to personal preferences myself, tend to run it and use the recommended EQ they advise. See attached ARC pre and post settings. Quite the mid range dip and peaks there.

So far, sticking to 80HZ x over but will experiment at some point. Right now, wanted to get used to the much enhanced base output I'm getting from the dual sub arrangement.

I know it looks very reflective, but just out of the photo are rugs, couch, large fluffy dog beds, etc. Not perfect to be sure, but as a shared space, best I'm gonna do.

 

[multichannel_guy]

Anyone using the FM8 to compliment a front stage (front left/center channel/front right) with the 250 hz crossover? How would the placement be for such an application?

 

[jtatknox]

I am considering using FM8 as a bass swarm with DLBC and Dirac Active Room Treatment, which can send cancellation waves up to 150 Hz. Any advantage of the clarity of smaller drivers in the midbass region for this purpose over e.g. L12?

 

[eboleyn]

I considered both dual FM8s or L22s for a while, but ended up buying a pair of F18s instead and my monitors sit on top of them. I currently cross at 80 Hz, but have tested crossing higher even up to 160 Hz and it still worked well.

 

[jtatknox]

Those are very different products indeed! Home theater use mostly?

 

[eboleyn]

Those are very different products indeed! Home theater use mostly?

For the F18s? It's dual-use Home Theater and Music, sitting under some DIY speakers I made.

Admittedly most music recordings don't care about the ability of the F18s to dig into really low frequencies cleanly, but when they do, they sound simply amazing!

More directly related to the current thread, using them in the dual stereo sub setup also lets me be more free with my DIY designs. The current ones can dig pretty low as long as you don't care about SPL (i.e. for nearfield listening you could do moderately well without a sub), but my nextgen design might need to cross over at like 120 Hz or so, and I like the flexibility.

 

[jtatknox]

For the F18s? It's dual-use Home Theater and Music, sitting under some DIY speakers I made.

Admittedly most music recordings don't care about the ability of the F18s to dig into really low frequencies cleanly, but when they do, they sound simply amazing!

More directly related to the current thread, using them in the dual stereo sub setup also lets me be more free with my DIY designs. The current ones can dig pretty low as long as you don't care about SPL (i.e. for nearfield listening you could do moderately well without a sub), but my nextgen design might need to cross over at like 120 Hz or so, and I like the flexibility.

I've gotta hear 18s one day.

 

[eboleyn]

I've gotta hear 18s one day.

If anyone's in or passing through Portland/Oregon/USA a demo could be arranged.

 

[WillBrink]

For the F18s? It's dual-use Home Theater and Music, sitting under some DIY speakers I made.

Admittedly most music recordings don't care about the ability of the F18s to dig into really low frequencies cleanly, but when they do, they sound simply amazing!

More directly related to the current thread, using them in the dual stereo sub setup also lets me be more free with my DIY designs. The current ones can dig pretty low as long as you don't care about SPL (i.e. for nearfield listening you could do moderately well without a sub), but my nextgen design might need to cross over at like 120 Hz or so, and I like the flexibility.

I'm confused now. Fm8 or F18? Thread was on Fm8 dual 8" subs.