[Early B.]

I was just thinking that if you wired the 3 woofers together on the right, you could use a single amp for the right. 

Then wire the 3 woofers together on the left and use a single amp for those 3.

Geez, now you tell me!!  

I like the idea of a separate amp for the middle sub because I can dial in subtle differences/volume distinct from the settings on the subs for the main speakers. Nonetheless, had I known what you suggested beforehand, I probably would have saved money on the third A370. Of course, Danny would probably say that the longer wire length to the third driver would be problematic. 

[nlitworld]

You could also run a y-splitter for your sub outs to put the center sub as receiving both channels.

[Tyson]

Geez, now you tell me!!  

I like the idea of a separate amp for the middle sub because I can dial in subtle differences/volume distinct from the settings on the subs for the main speakers. Nonetheless, had I known what you suggested beforehand, I probably would have saved money on the third A370. Of course, Danny would probably say that the longer wire length to the third driver would be problematic. 

Cool thing about DIY is you can always make changes and see if you like it better and change it back if you don’t.

[Early B.]

You could also run a y-splitter for your sub outs to put the center sub as receiving both channels.

If I'm understanding you correctly, it's not recommended to use the subouts on the A370 because they're filtered at 80Hz. Besides, I prefer a direct connection to the preamp.



 

[Early B.]

Cool thing about DIY is you can always make changes and see if you like it better and change it back if you don’t.

Yeah, there are tons of options for tweaking the bass to taste. But Tyson -- you got me thinking like a mad scientist -- I can add a single servo sub to each of the dual subs and turn them into triples.   Imagine that -- 9 OB woofers in a 13x20 room -- whoa!! 

[nlitworld]

If I'm understanding you correctly, it's not recommended to use the subouts on the A370 because they're filtered at 80Hz. Besides, I prefer a direct connection to the preamp.

I was actually speaking from your preamp, have a pair of rca y-splitters (1 rca male plugged into your preamp output - 2 rca female out with rca wires to your subs). Run one of the L channel to the left vertical stack, run one of the R channel to the right vertical stack, then run the remaining L & R to the center horizontal sub. That would for the center effectively sum both into that to even out your L vs R soundstage. Y-splitters are a bit hoaky but effective in this case. I'm sure if you talked to any of our skilled wire craftsmen here they could even make a fancy audiophile grade one or just rig up a small plastic box unit similar to Danny's high pass filter units, just with no capacitors in the box. Just a thought. 

[Tyson]

Yeah, there are tons of options for tweaking the bass to taste. But Tyson -- you got me thinking like a mad scientist -- I can add a single servo sub to each of the dual subs and turn them into triples.   Imagine that -- 9 OB woofers in a 13x20 room -- whoa!! 

This is why I love my fellow audiophiles. 

Me: Hey maybe you could rewire the subs and consolidate from 3 amps to 2 amps.
You:  OR I could keep the 3 amps and add more woofers! 

Haha, a man after my own heart

[Early B.]

I was actually speaking from your preamp, have a pair of rca y-splitters (1 rca male plugged into your preamp output - 2 rca female out with rca wires to your subs). Run one of the L channel to the left vertical stack, run one of the R channel to the right vertical stack, then run the remaining L & R to the center horizontal sub. That would for the center effectively sum both into that to even out your L vs R soundstage. Y-splitters are a bit hoaky but effective in this case. I'm sure if you talked to any of our skilled wire craftsmen here they could even make a fancy audiophile grade one or just rig up a small plastic box unit similar to Danny's high pass filter units, just with no capacitors in the box. Just a thought. 

Oh, gotcha!  OK, I'll give it a try and report back. I'm sure I have an extra Y-splitter around here somewhere.

[CaptainDidactic]

I have a set of NX-Otica's and double troubles. I use the plate amps from Danny and are powering the Oticas with a McIntosh MA 12000. I got a chance to audition a MEN 220, a room correction unit built by McIntosh, McIntosh licensed RoomPerfect technology from Danish audio wizard Peter Lyngdorf, whose Steinway Lyngdorf music systems cost upwards of a couple hundred grand. Here is where the plot thickens.

Friends and I dialed in the phase and the levels on the plate amps to sound good with the NX-Oticas, we thought we did a great job. At first, we used the Men220 and the room correction software just controlling the Oticas, but when we re-ran the whole set-up and allowed the Men220 to adjust all the levels, the music went from great to Outstanding.

What we did was allow the Men220 to set all the levels. We turned all the switches on the plate amp to "11" and let the Men220 do it's thing. The overall bass and punch increased dramatically. The unit did a great job of blending the sounds of all of the speakers. 

Before I ran the double troubles through the Men200 I was really on the fence whether I actually liked the sound, but once I gave it full control.... all I can say is Wow!

[HAL]

I am thinking bigger.

Time to get the 12 1x12 modular OB servo sub H-Frames to painting next week. 

[BrandonB]

I am thinking bigger.

Time to get the 12 1x12 modular OB servo sub H-Frames to painting next week. 

WOW Watcha gonna do with that?

[HAL]

They go with my new AGN II Line Array speaker project.

Pics on my circle in that thread.

[Early B.]

You could also run a y-splitter for your sub outs to put the center sub as receiving both channels.

OK, I'm reporting back on running two y-splitters to turn my middle sub into a "stereo" sub....

Lo and behold, the middle sub (or all three OB subs?) sounds like a giant sealed sub, i.e., you get the gut punch that isn't usually associated with OB subs. It was a little boomy initially, so I reduced the volume and changed the damping setting to "Low" on the A370 amp. The bass sounds better now. Frankly, I didn't expect an improvement, but I'm glad I tried it, and it was a cheap tweak. Nlitworld -- thanks for the suggestion.

[Denton J]

Is there a connection type listing for the GR subs? I'm assuming there are high level inputs, is there LFEs for the single box GR subs version?

[HAL]

For the high level output, people typically use Neutrik Speakon 4-pole connectors with the servo amps and drivers since they have 4 connections.

The standard has been 1+ and 1- for the driver coil and 2+ and 2- for the servo coil connections on both the amp and drivers.

[mlundy57]

Is there a connection type listing for the GR subs? I'm assuming there are high level inputs, is there LFEs for the single box GR subs version?

It depends on the model of the A370 amp you use. The A370PEQ and PEQ3 have high level speaker and line (low) level RCA inputs. The PEQ has left and right RCA inputs and left and right RCA outputs that have an 80Hz high pass filter but don’t use that. The PEQ3 has left and right RCA inputs and an RCA LFE input.

The A370XLR2 and XLR3 versions have both RCA and XLR inputs but do not have high level speaker inputs

[Denton J]

Thanks Mike.

[Hafgrim]

I decided that I wanted to build a set of double troubles but since I had recently blown my cash on a meitner ma3 dac, I decided to build a set for the cheapest amount of money.

I substituted the 600 or so for the the flat pack and built my own for around 100.
And I substituted the 2400 I drivers and amps from gr with 4 sb audience bianco 12ob150 for 400 and a crown xls1002(built in crosover) that I had laying around.

I also bought 4 sheets of no rez, good stuff!

Total cost for me was around 750$. A steal compared to 3k+. 


Drivers and my tools.


Cut mdf



Glue up



Setup



I am extremely satisfied with this project. Although the woofers only rated for around 40hz, thanks to the hfame design and room gain I get usable output down to 25 hz.

The amp does have have a crossover built in but not a phase adjustment. Thankfully I was able to get by, by just inverting the phase in the speaker wiring.

I am very happy with the sound of these subs. They replaced a single rythmic f12se and 2 rythic f8 subs. I get Much cleaner bass from these 2 subs Than the rythmiks.

[Hafgrim]

Theese are the woofers I used. Fs is at 44 but it seems that the hframe pushed it down some.

These have a high sensativity, high qts and a fair bit of xmax.

The only other drivers like these are much more expensive offerings from acustic elegance and lii audio.

I might decide to upgrade to the ae dipole 12s in the future.
I think I might have too much fun upgrading amps for the subs too go use the rythmic woofers and amps.

It would be interesting to use big krells for the bass in the future. 

https://www.sbaudience.com/index.php/products/open-baffle-drivers/bianco-12ob150/

[Early B.]

I am very happy with the sound of these subs. They replaced a single rythmic f12se and 2 rythic f8 subs. I get Much cleaner bass from these 2 subs Than the rythmiks.

Awesome! The statement above says a lot.