DIY Rythmik Audio Direct Servo 12" sealed 56L - Home Theater Forum and Systems - HomeTheaterShack.com

 
Thread Tools
post #1 of 16 Old 07-30-07, 12:14 PM Thread Starter
Elite Shackster
 
Ilkka's Avatar
Ilkka
 
Join Date: Jun 2006
Location: Finland
Posts: 1,468
DIY Rythmik Audio Direct Servo 12" sealed 56L

Manufacturer: DIY/Rythmik Audio
Provided by: Ilkka
Manufacturer link: Rythmik Audio
Price: ~750 EUR

Manufacturer specs:
• Woofer: Rythmik Audio DS12TC
• Rigid anodized aluminum cone (black or silver)
• Rigid 12 spoke cast aluminum basket
• FEA designed aluminum short circuit ring to reduce 2nd order distortion
• High linear excursion capability of 1.4" peak to peak (xmax)
• High mechanical excursion capability of 2.6" peak to peak (xmech) to reduce risk of bottoming
• Very low inductance
• 24 ohm ultra thin sensing coil for servo operation keeps moving mass low
• Woven wire lead in the spider to prevent rattling during high excursion
• Gold spring loaded terminals for easy solderless cable connection
• Single 2.8 ohm voice coil
• Available with rubber mounting gasket (12-9/16" outer diameter and 3/4" depth)
• Mounting without gasket (12-3/8" outer diameter and 3/8" depth)
• Two 1" stacked magnets for a total magnet height of 2"
• 350W RMS max power
• Proudly made in USA
• Amplifier: Rythmik Audio A370 Direct Servo amplifier
• Output Power (4ohms): 350W RMS
• Op amps: OPA2134/TL072
• Power amp inputs: MOSFETs
• Subwoofer roll-off: 12 or 24 dB (not selectable)
• Power filter caps: 4x100V/6800uF
• Warranty: 2yr
• Enclosure: 56 liters (2 cubic feet), 19 mm MDF (double front baffle), braced

Configuration as tested:
Phase: 0 degrees
Crossover: Max
Extension filter: Hi-damping (Q=0.6), 14 Hz extension
Orientation: Woofer facing the mic



Ilkka is offline  
Sponsored Links
Advertisement
 
post #2 of 16 Old 07-30-07, 12:14 PM Thread Starter
Elite Shackster
 
Ilkka's Avatar
Ilkka
 
Join Date: Jun 2006
Location: Finland
Posts: 1,468
Re: DIY Rythmik Audio Direct Servo 12" sealed 56L



+/- 3 dB points: 12.5 Hz - 109 Hz
Ilkka is offline  
post #3 of 16 Old 07-30-07, 12:14 PM Thread Starter
Elite Shackster
 
Ilkka's Avatar
Ilkka
 
Join Date: Jun 2006
Location: Finland
Posts: 1,468
Re: DIY Rythmik Audio Direct Servo 12" sealed 56L



Ilkka is offline  
post #4 of 16 Old 07-30-07, 12:15 PM Thread Starter
Elite Shackster
 
Ilkka's Avatar
Ilkka
 
Join Date: Jun 2006
Location: Finland
Posts: 1,468
Re: DIY Rythmik Audio Direct Servo 12" sealed 56L



Ilkka is offline  
post #5 of 16 Old 07-30-07, 12:15 PM Thread Starter
Elite Shackster
 
Ilkka's Avatar
Ilkka
 
Join Date: Jun 2006
Location: Finland
Posts: 1,468
Re: DIY Rythmik Audio Direct Servo 12" sealed 56L



Ilkka is offline  
post #6 of 16 Old 07-30-07, 12:15 PM Thread Starter
Elite Shackster
 
Ilkka's Avatar
Ilkka
 
Join Date: Jun 2006
Location: Finland
Posts: 1,468
Re: DIY Rythmik Audio Direct Servo 12" sealed 56L



Ilkka is offline  
post #7 of 16 Old 08-21-07, 04:21 PM
Senior Shackster
Russell
 
Join Date: May 2006
Location: Cambridge, UK
Posts: 142
Re: DIY Rythmik Audio Direct Servo 12" sealed 56L

Ilkka,

I'm particularly interested in your thoughts on the Rythmiks especially now I see you've expended some of your own hard earned on one. I presume you wanted to test the water yourself?

As a Monolith owner in a 1500ft^3 room (potentially about to step up to a 2500ft^3 room), Im interested in something that will at least maintain current SPL levels whilst offering deeper extension and keep a lid on distortion. In the smaller Euro room (and given the current exchange rates) the Servos look like good value, but I'm having trouble penetrating the (admittedly short of SVS levels) of hyperbole on the website.

I was leaning toward the 15" servo kit in a 3-4 cu ft sealed box as the dual 12" would just be too large at 6ft^3. I read your results, add on the min claimed boost of 3dB, add on the room gain 6-12dB/octave and I'm arriving at some scarcely believable potential in room figures considering the power outputs of the amps and the power requirements of a sealed box.

Anybody's thoughts are welcome for that matter.

Russell

Mitsubishi HC6000 : Carada 88" Precision Series screen : Sony PS3 : Audiolab 8000CD : Audiolab 8000AP : Cinepro 2k6 : XTZ 99.25 fronts & center : M&K Xenon 25 and LCR 25 surrounds : BFD : EP4000: Dual AV15-X 4cu ft sealed subs

Last edited by russ.will; 08-23-07 at 05:04 PM.
russ.will is offline  
post #8 of 16 Old 08-22-07, 09:33 PM
Shackster
 
bone215's Avatar
Bone
 
Join Date: Dec 2006
Location: NEAR PHILLY
Posts: 53
Re: DIY Rythmik Audio Direct Servo 12" sealed 56L

I, also, would like to read more about the sub and how it sounds.
Thanks.
bone215 is offline  
post #9 of 16 Old 08-23-07, 04:35 PM Thread Starter
Elite Shackster
 
Ilkka's Avatar
Ilkka
 
Join Date: Jun 2006
Location: Finland
Posts: 1,468
Re: DIY Rythmik Audio Direct Servo 12" sealed 56L

Quote:
russ.will wrote: View Post
Ilkka,

I'm particularly interested in your thoughts on the Rythmiks especially now I see you've expended some of your own hard earned on one. I presume you wanted to test the water yourself?

As a Monolith owner in a 1500ft^3 room (potentially about to step up to a 2500ft^3 room), Im interested in something that will at least maintain current SPL levels whilst offering deeper extension and keep a lid on distortion. In the smaller Euro room (and given the current exchange rates) the Servos look like good value, but I'm having trouble penetrating the (admittedly short of SVS levels) of hyperbole on the website.

I was leaning toward the 15" servo kit in a 3-4 cu ft sealed box as the dual 12" would just be too large at 6ft^3. I read your results, add on the min claimed boost of 3dB, add on the room gain 6-12dB/octave and I'm arriving at some scarcely believable potential in room figures considering the power outputs of the amps and the power requirements of a sealed box.

Anybodies thoughts are welcome for that matter.

Russell
Hi Russel and Bone,

The 12" sealed Rythmik Audio DS is generally a really good subwoofer. It has versatile settings for extension and shape of the frequency response, which both help to match the subwoofer and the room. I don't want to say a lot of subjective comments about its sound because the listening room and personal preference affect a lot to it. I can say that its sound is slightly drier than what we usually hear with other subwoofers. That might be a good or bad thing, depending what kind of sound one likes. The upper end stays really clean even when pushed really hard, but when listening to material with lots of high amplitude low frequencies (HT use), you will start to hear some amp clipping noises (ticking, crackling) at certain point. In my small room this was around 102-105 dBC measured around 2.5 meters from the subwoofer. The subwoofer will still go louder, but not without these noises. They can be hard to hear when other speakers are blasting, but if you turn them off, you will notice when the subwoofer starts to overload. Brian decided not to use any amp limiters, which helps to preserve the maximum dynamic capability of the amp. But as you can see from the THD graph, distortion grows pretty large below 30 - 40 Hz when pushed hard. If one is using one of the lesser extension settings, naturally the low end compression and distortion are lowered too. You should notice that I used the lowest extension and low-Q settings in my tests, which make the compression and THD graphs look somewhat worse when compared to subwoofers with lesser extension. So always remember to check the real output and extension from the frequency response and maximum output graphs when making any comparisons.

If one wants to match the clean (no overloading noises) output in 20 - 30 Hz range with the Monolith, one needs two of the 12" kits or one of the 15" kits (estimate since I haven't measured the 15" kit). The 15" kit should be around 3 - 5 dB louder than a single 12" kit. I would recommend using a 4 cu ft box with the 15" kit for higher deep bass sensitivity. I would recommend this as a minimum configuration for a home theater use, especially if you want to use higher than medium listening levels.
Ilkka is offline  
post #10 of 16 Old 08-23-07, 05:21 PM
Senior Shackster
Russell
 
Join Date: May 2006
Location: Cambridge, UK
Posts: 142
Re: DIY Rythmik Audio Direct Servo 12" sealed 56L

Thankyou. That is exactly the sort of info I was looking for.

I find your comment regarding the "dry" bass quality of particular note. I like deep extension without necassarily overblowing LF boost. In other words, my house curve isn't exactly as savage as some others I've met and probably goes someway to explaining why the stereo crowd like the Rythmiks.

Given you comments on audible limits, I'll ignore the single 12" designs. The Monolith is delivering comfortable 105dB+ in the mid to low 20Hz at my listening position 3.5m from the sub. I think I would kill a single 12" servo in fairly short order. My recent experiments with dual subs also showed me that I favour one large sub over two small ones, so I'll probably go the 15" route.

In fact, given that the US $ is so weak at the moment and there isn't a larger otion than 15", I'm almost tempted to consider two 15" anyway. With the SMS-1, I could set up one preset for one sub with music and then other presets for two subs and raising the roof with movies.

Thanks again,

Russell

Mitsubishi HC6000 : Carada 88" Precision Series screen : Sony PS3 : Audiolab 8000CD : Audiolab 8000AP : Cinepro 2k6 : XTZ 99.25 fronts & center : M&K Xenon 25 and LCR 25 surrounds : BFD : EP4000: Dual AV15-X 4cu ft sealed subs
russ.will is offline  
 

Bookmarks

Tags
56l , sealed

Quick Reply
Message:
Options

Register Now




PLEASE COMPLETE ALL REQUIRED FIELDS BELOW... THANKS!

REQUIRED FIELDS ON THIS PAGE
YOU MUST COMPLETE ALL OF THESE

Username
Password
Confirm Password
Email Address
Confirm Email Address
Random Question
Random Question #2




User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
PLEASE READ BELOW PRIOR TO ENTERING AN EMAIL ADDRESS!

ATTENTION!

YOU MUST ACTIVATE YOUR ACCOUNT!

Activation requires you reply to an email we will send you after you register... if you do not reply to this email, you will not be able to view certain areas of the forum or certain images... nor will you be able download software.

AN INVALID EMAIL ADDRESS WILL CAUSE YOUR ACCOUNT TO BE DELETED!

See our banned email list here: Banned Email List

We DO NOT respond to spamcop, boxtrapper and spamblocker emails... please add @hometheatershack DOT com to your whitelist prior to registering or you will get nowhere on your registration.


Email Address:
OR

Log-in









Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.


Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML is not allowed!
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

 


For the best viewing experience please update your browser to Google Chrome