[HAL]

If you are running the amplifier outputs as inputs to the A370PEQ, then you need both + and - wires.  Do that for both servo amps. 

[mlundy57]

My question is not about running from the preamp to the servo amps, but from the the poweramp to the servo amps. So in this case one would run the possitive leads from the amp to the servo amp inputs, but is it recommended to also run a negative.

Rocket Ronny

If you are using the speaker binding posts from the power amp to the speaker level inputs on the Rythmik and then you connect it like you would a pair of speakers, both positive and negative leads.

If your power amp has multiple pairs of speaker binding posts, connect the Rythmik amp to the same pair of binding posts your speakers are connected to.

If your power amp has two pair of binding posts (A speakers and B speakers) and you connect the speakers to A and the Rythmik plate amp to B you will likely blow the amp. I did that and now I have a dead power amp to send off for repairs.

Mike

[Rocket_Ronny]

Now those are the answers I am looking for. Thanks

With some subs they only want the positives and one negative hooked up, so these are different that way.

Rocket Ronny

[SoCalWJS]

Ah, THROWBACK just sent me his diagram that he created and asked me to post it.  Here it is, feel free to use it:

I've had a copy of this for awhile, but never printed it out and used it. 

Decided to give it a try and printed out several copies. Noticed that the frequencies matched up with Alan Parson's Sound Check 2 disc and pulled it out. Fired up my old Radio Shack Digital SPL Meter (and a fresh battery) and settled in for the long haul while the Wife was away.

After running through the thing a few times (one channel at a time), something started to click and my random changing of levels began to make more sense. Pretty soon I had a reasonably consistent level at frequencies from 20 - 400 with a peak around 125 that I still need to tame. My big dropout around 60-70 is gone!

I then pulled out the Omnimic and checked the FR with it - pretty much the same. Very happy with the results.

Full, powerful, clean Bass with no muddiness or bloat. Fast when it should be. No room excitation on my problem wall. Overall listening is improved even further. I'm back to playing around with the room treatments trying to get the best soundstage that I can in the room (definitely different then before - I don't like it as well with the treatments where they were previously. New/different locations resulting in better sound)

Thank you THROWBACK for making this sheet! Highly recommended for anybody. It is so much easier with things written down in a well organized fashion than trying to remember what you changed a couple of attempts back.....

[JLM]

Well, if you are just going for SPL levels then that will do it.

You've got the wrong idea Danny.  With the right shape giant concrete bass horns provide highly dynamic, un-colored sound.  Horns need to be big to go really low.  Concrete construction is needed to have sufficient wall stiffness to avoid wall flexing distortions. 

[THROWBACK]

"Thank you THROWBACK for making this sheet!"

You're welcome, SoCalWJS. I'm happy you found it useful.

[Danny Richie]

You've got the wrong idea Danny.  With the right shape giant concrete bass horns provide highly dynamic, un-colored sound.  Horns need to be big to go really low.  Concrete construction is needed to have sufficient wall stiffness to avoid wall flexing distortions.

I am sure that they can be very dynamic, but it is still a far cry from being the highest level of bass reproduction. You still have to deal with how it loads the room, or overloads the room. Evening out the room loading would be next to impossible. And you are still limited in quality to the longer settling times on an uncontrolled driver.

I'll take servo control with open baffles any day.

[rollo]

Simple, Bass = OB subs. Two per side and be happy real happy.

charles

[gregfisk]

Simple, Bass = OB subs. Two per side and be happy real happy.

charles

+1 

[narkotic]

If I were to pair some OB GR woofers with, let's say an Apogee Scintilla MRTW array (deleting the woofer panel) could the 370 amp go up to 300hz? Can the woofers even go that high? They are labeled as subwoofers so maybe not? I don't really want / like a separate subwoofer for music.

The woofer on the Scintilla is 300Hz @ 6dB (First Order).

Doing this so I have the best of both worlds, ribbon highs and cone lows. Or will I need to go active?

The 370 amp seems to only go to 120hz, via the dial.

I'm thinking of 3 12" 16Ohm subs per side in H Frame. For fun.

[Danny Richie]

If I were to pair some OB GR woofers with, let's say an Apogee Scintilla MRTW array (deleting the woofer panel) could the 370 amp go up to 300hz? Can the woofers even go that high? They are labeled as subwoofers so maybe not? I don't really want / like a separate subwoofer for music.

The woofer on the Scintilla is 300Hz @ 6dB (First Order).

Doing this so I have the best of both worlds, ribbon highs and cone lows. Or will I need to go active?

The 370 amp seems to only go to 120hz, via the dial.

I'm thinking of 3 12" 16Ohm subs per side in H Frame. For fun.

The number in the crossover dial on the A370 amps are reference points relating to the electrical slope. They are not a crossing over point. The crossover point is where the acoustic output of the two drivers are both 6db down.

And I have crossed the A370 amp driving dual SW-12-16FR woofers as high as 300Hz. 

For reference, on the Super-7's the crossover point is in the 180Hz range to the planar magnetic Neo 10's. So the setting on the crossover dial is in about the 90Hz range.

[narkotic]

Fascinating. I still have a lot to learn from you.

I'm still working on the wife to allow me to purchase 6 OB subs and 2x OB H Frame Cabinets. Then I'll have both a Scintilla MRTW array to mate with it as well as a electrostatic panel, for fun

While I love the bass from the Scintilla ribbon, it's both A. HUGE in size, B. Not the best for the music I listen to (synthesized bass so it will "bottom out" so to speak) and C. Hard to drive.

[Tyson]

Fascinating. I still have a lot to learn from you.

I'm still working on the wife to allow me to purchase 6 OB subs and 2x OB H Frame Cabinets. Then I'll have both a Scintilla MRTW array to mate with it as well as a electrostatic panel, for fun

While I love the bass from the Scintilla ribbon, it's both A. HUGE in size, B. Not the best for the music I listen to (synthesized bass so it will "bottom out" so to speak) and C. Hard to drive.

Be very careful here.  Once you get used to Servo OB bass, you'll have a very hard time listening to any other bass systems    

One thing you might do - see if you can get the OB subs finished to match the finish on the Apogees, so visually it looks nicer and less random. 

[narkotic]

Well if I remove the MRTW assembly from the Scintilla, there will be no facia to replicate. But I agree, it would be cool if they looked alike. Or piano black OB frames and piano red MRTW facia that will have to be made. The MRTW array (naked) is just ugly steel.

[Captainhemo]

Piano Black is  a PITA,  these went back for   polishing twice  before we shipped.  gfrills are actually black too,   flash makes them look grey.
Nice to look at,   don't touch...  buy lots of  dust  Off   

jay

[narkotic]

Piano Black is  a PITA,  these went back for   polishing twice  before we shipped.  gfrills are actually black too,   flash makes them look grey.
Nice to look at,   don't touch...  buy lots of  dust  Off   

jay

Beautiful! I've had piano black speakers before, and yes I agree they are a PITA, just like anything black and glossy

If you assembled those first and painted, the shipping cost must have been nuts, unless he's a local bloke.

Your prices for flat packs, is that including shipping or is that additional? To zip 92844?

[Captainhemo]

Beautiful! I've had piano black speakers before, and yes I agree they are a PITA, just like anything black and glossy

If you assembled those first and painted, the shipping cost must have been nuts, unless he's a local bloke.

Your prices for flat packs, is that including shipping or is that additional? To zip 92844?

Wasn't local,   sending them out finished   does increas the shipping  costs, the box for each  dual sub ends up being  24"x24"x36",  approx 75 lbs.  We get  2 flat packs in less  than half of that volume .

Flat pack pricing  does NOT include shipping..... no mark up though, you  pay  what the quote says .

jay

[maty]

Rythmik Audio F12G Direct Servo Subwoofer In-Depth Review 2013 -> 2020, by Erin Hardison (hardisj)

https://www.erinsaudiocorner.com/loudspeakers/rythmik-f12g-direct-servo-subwoofer/







[ Raw Subwoofer Drive Unit Conclusion:

On its own, this driver performs really well. The low Fs of 20.8Hz, reasonable enclosure size requirements, good linearity, and low distortion with nearly 18mm one-way linear excursion all are attributes that make this a great value at its current MSRP of $179. I honestly would have no issue at all recommending it. Getting down to brass tacks, what this means is with the F12G Subwoofer, you know you have a great starting point with the SW-12-04 driver.

One thing that is a nice added touch is the felt material on the underside of the cone (shown in the pictures above). This is to minimize any audible tinsel lead slap on the cone. And I can say without a doubt, as I was testing this woofer to very high excursion levels (likely higher than anyone would actually achieve in real use), I never once heard any mechanical noise from the woofer driver.

Overall, the Harmonic Distortion components at 2.83v/1m are really low. The red PHD line is a representation of perceived harmonic distortion. You’ll note this is very, very low. With 20v input, putting the mean SPL from 20 to 300hz at about 98dB, THD climbs to about 3% THD at 60hz. However, this is mostly comprised of 2nd order distortion while 3rd order distortion is below 1.5%. Whether or not this is an audible factor seems to be of hot debate. The key here is the relationship between 2nd and 3rd order and that they’re well separated, indicating no serious flaws in the driver. ]






http://www.rythmikaudio.com/F12G.html

[Captainhemo]

Keep in mind, that  driver  is for  sealed enclosures, not  OB  use.  For OB use, you  need to use    either the  SW12 08FR  ( in duals/quads ) or the  SW12 16FR (duals, triples, quads,  or    arays of 6). 

jay

[Tyson]

I'll say that the sealed FG12 woofer is the best box bass I've heard.  But yeah, it's not going to hold a candle to the dual OB servo subs for music.