[bjarnetv]

i am contemplating building a speaker using an h-frame setup similar to the super-v in the bottom end, but after reading about the a370peq i am slightly confused 
i am planning to use a jatzen JA8008 midrange, so i will need a 200hz crossover, and i have seen Danny mentioning that its possible to do, but i just cant seem to figure out how?
from looking at pictures, it seems 120hz is the highest crossover point available?

anybody care to enlighten me? 

[Danny Richie]

Markings on the amp are reference points related to an electrical slope. It is not an acoustic output figure.

Also, true crossover points are where the curves of each are 6db down.

So for the Super-V to cross to the upper driver at 200Hz you have to set the dial to about 90.

[bjarnetv]

thanks for the clarification 

[bjarnetv]

ok, so one more question.

how much headroom do you get with two sw-12-16fr connected to the a370peq?
the woofers are rated at 84,7db, and wired in parallel end up with 8ohms.
doubling the woofers give a gain of 3db, but i guess you lose that by putting them in an H-frame?
i also don't know how much power the amp deliver at 8ohms?

I'm kind of worried this setup run out of steam too soon when paired with a high efficiency mid and tweeter.

[Danny Richie]

ok, so one more question.

how much headroom do you get with two sw-12-16fr connected to the a370peq?
the woofers are rated at 84,7db, and wired in parallel end up with 8ohms.
doubling the woofers give a gain of 3db, but i guess you lose that by putting them in an H-frame?
i also don't know how much power the amp deliver at 8ohms?

I'm kind of worried this setup run out of steam too soon when paired with a high efficiency mid and tweeter.

A pair of the SW-12-16FR's were used in the Super-V's: http://gr-research.com/super-v.aspx

The Super-V's had 97db sensitivity.

The two woofers kept up pretty easily. Gain settings on the amp were typically turned up to about a 1 o'clock setting to keep them balanced. That will vary some depending on the input signal strength, but there was never a condition where the woofers couldn't keep up in the SPL department. I have had a pair of the Super-V's hit over 112db in a larger open room all the way down to 20Hz.

[bdp24]

An option to consider is using three drivers per side. That will give you more output from not only the extra driver, but also the combined impedance of three drivers dropping to around 4 ohms, where the A370 will be putting out it's full 370 watts.

[bjarnetv]

three drivers per side would make the speaker too tall, so that's out of the picture 
I'll be getting the mids soon, so i will decide what to do with the bass after measuring them; see how low they will go.
right now gr drivers in an H frame seems like the best option, but i fear the shipping to norway 

at them moment i'm using dual 15" in a shallow U frame, but that makes the speaker a bit too tall so i have too downsize 

[bdp24]

A three GR-driver H-Frame can be placed on it's side, it doesn't have to be standing upright. That would take up some floor space, however!