[Tinear1]

Hi all...  I am interested in the GR OB subs to compliment my horn system.  I have read quite a bit about the OB trade offs and question if the OB output SPL will be high enough to supplement my system.  I an looking to use the OB subs to cover only the 20-80hz range. 

My room is 14x18 w/ vaulted ceiling and I do tend to play jazz / blues / rock rather loud... at club session levels.  So will a pair of the 2x12's per side have enough output in the 20-80Hz range to keep up?

Best regards

[corndog71]

Yes.

[Tyson]

More than enough. 

If you own Horns, then most likely dynamic swings are important for you.  You'll find that servo controlled OB subs are really the only design clean/fast enough to keep up with really great horn speakers.  Box subs just don't cut it with a system that is that demanding.

[Tinear1]

I fully understand the OB speed capabilities and that's why I am interested.  My concern is will there be enough output SPL and slam at higher listening levels?

[Tyson]

I fully understand the OB speed capabilities and that's why I am interested.  My concern is will there be enough output SPL and slam at higher listening levels?

2 per side will be fine.  3 will be better and 6 would be best!  But then I'm a guy that thinks you can never have too much bass capabilities.   

[Captainhemo]

Don't forget about  quads ,  and ,  you  can use the 8 ohm woofers with  them 

How efficient are your horns  ?    2 per side keeps up   very easily with the 97db efficient Super 7's

jay

[Tinear1]

@Captainhemo... My horns are 104dB efficient BD-Design Orphean's w/ reference base cabinets.  Sounds wonderful but the -3dB down point is only 44Hz and I need to fill in down to 20Hz so an upper xover at 80-100 would be on and if I could get up to about 450Hz then I could delete the current base cabinets.  As for 3 or 4 per side; I could use the 3's if I don't need the current base cabinets.  Possibly 4 per but... I assume the wiring would be (8+8) serial x2 then those pairs in parallel for 8Ohm net per side.  Would the servo wiring still be all in serial in such an arrangement?  Looks like a lot of cone area for a single A370 per side since 370w at 4Ohm and only ~ 250w at 8Ohm.

[Tinear1]

bump

[Captainhemo]

Withthe quads or 6 stacks, you'd need to use the HX800 amps . They have  2 400w modules in each mp in master / slave config.  So,  2 woofers in each 4 stack  run of one  modulel......  each has it's own  servo circuit leads as well.

Eg,  bottom 2 woofers    driver coils  wired in parallel off  one module, servo coils  in series  of same module.  Upper  2  woofers,  driver coils  in parallel , from  2nd module, servo coils in series  from 2nd module.  Both modules in each HX800 are  controlled  by same  controls.   Wiring color coding is a bit different  in the HX800,  coding is shown   in the   H-frame  wiring  thread   (sticky)

Wire  any rearward facing woofers   out of phase on  both driver/ servo coils

I believe the highest  you're going to get these to cross is  around  200Hz withthe   built in  c/o  of the HX800

With quads, use either 8 or 16 ohm woofers,  6 stacks require the 16 ohm version

jay

[Tyson]

You should be fine with 2 per side. 

[Danny Richie]

Those duals were under the Old Super-V's. See some good pics here: https://www.audiocircle.com/index.php?topic=73341.0

Those upper drivers were 98db sensitivity. They keep up fine with those and my ears would give out long before the woofers ability to keep up.