12" Shiva #121947 dual vc driver

[hpsenicka]

The selection of an optimal crossover point is an interesting decision in this case.... made either more challenging or more straightforward by the inherently good bass handling characteristics of the AR-9s.

Do you let the AR-9's run full range and just let the sub fill in the bottom end at the point where the AR-9's are not as effecitve?

or...

Do you limit the bottom end of the AR-9's a wee bit, and let the subs take over?

Striking an appropriate balance here will be interesting....

(WARNING: I have very limited experience with subs and crossovers... so please don't take this post as advice! I'm just thinking out loud and wondering how best to approach this.)

 

[bolly]

thanks pete

hi hp, I think I'll leave the AR9's be, just as they are. These subs will... hell, I don't even know what I'm gonna do with these subs yet, but I'll have fun tryin!

 

[bolly]

ordered 2pr of the 70Hz FMOD last night. Might as well give them a try, hear what happens.

 

[bolly]

it just, and I mean just

dawned on me.

I think I only need one pair, damn! :sigh:

I confused myself as each sub has 2 sets of binding posts, oh well, looks like a good excuse to get a pair of monoblocs, or somethin.

 

[Charivari]

dawned on me.

I think I only need one pair, damn! :sigh:

I confused myself as each sub has 2 sets of binding posts, oh well, looks like a good excuse to get a pair of monoblocs, or somethin.

Um .. doh? Even a pair of mono blocks would only need a pair, unless you're planning on using a monoblock per voice coil. Well, maybe you'll find out that you like them, find a nearby AKer who wants them, or just plain return them. Still, this is yet another step closer to the horror (to the neighbors) of dual Shivas being driven by a Spec-2!

- JP

 

[bolly]

they lay dormant,



for now. :saywhat:

 

[Inspiribomb]

Those look badass sitting there dormant, for now...

 

[bolly]

thanks Ib!

some grills are required for these I think, round black ones, a little larger than 13"dia. Any ideas for what to use and how to attach them?

 

[luvvinvinyl]

1/4" neodymium magnets, in the cabinet, and screw & washer in the grille.

Check Lee Valley for these, with the matching cups and washers. I used mdf, and a circle cutter, to make round frames, and stretched cloth over them. They attach with a really satisfying "snick", and stay put, until you want to remove them. I used these to replace the velcro pads I tried first. Magnets are much better. The field of the neodymiums is small enough to have no audible effect on the driver. Very intense, but falls off quickly.

Oh, and resist the urge to get the big ones. The 1" will hold a sledgehammer up off the floor. And I can't seem to get the magnet off the I-beam, in my basement, where I put it, just to see how well it works. For the record, it works REALLY well.

 

[Inspiribomb]

I also think this is a good idea, but be careful with those neodymium magnets before mounting them, as they can wreck a lot of things really fast if you're not careful. Larger ones have been known to hurt people who don't know what they're dealing with.

 

[luvvinvinyl]

too true, 'bomb. I use spare 1/4" ones as fridge magnets. Best there is. Mind you, they are tough to peel off. Usually just slide them to the edge of the door.

 

[bolly]

great idea ernie! :thmbsp:

 

[kfa888]

Bolly,

Those look nice as end tables and it is a convenient placement but I think you might need to reconsider. Two things, first off sending the bass frequencies back towards your AR9's is going to cause some cancellation and raise havoc with your bass reproduction especially if you are wiring them stereo and facing them at your primary stereo source, the 9's. Second, although subs are kind of direction less and most people think placement does not matter I have found that placement is very critical. My suggestion is to run them beside your AR9's slightly in front (think time aligned) and do not drive them to where you can hear them over your 9's. With subs I have found a little goes a long ways. This will all be especially true if you plan to cross them higher like at 70. Think about it like it is a passive radiator or port to extend you bass reproduction on your AR9's. Sitting between those and pointing them from the opposite direction towards your sound field is about the worst thing you can do in my opinion. I have a big "American Acoustic" sub 200 watt / 15" down firing and placement is critical as is crossover and phase. Subs are trickier than you think to add and have it enhance your sound. 75% of the ones I hear are degrading the sound because of bad placement and crossover. My sub has a plate amp with adjustable crossover and phase adjustment. I also have a Klipch 6th order sub which has two drivers, one on each side and firing out and it is very sensitive to placement. It needs to be at odd angles to the walls or it gets boomy. Set it up just right and it is bliss. Just food for thought.

Oh, and I would run your AR9's full range (not limited) and let the subs just fill in from there on down. :yes:

Look at me giving technical advice. What the hell am I doing? Disregard all of the suggestions above.

 

[bolly]

can't fit them in anywhere's near the front, extremely poor WAF!

hi kfa,

I agree. I think I'll experiment first off by placing the subs facing outwards from the couch, side-firing... just like them 9's. :thmbsp:

 

[bolly]

well, well, well,

Looky what the UPS man just delivered. I'll be busy after work today!

 

[kfa888]

The 9's are prolly to tall to put the subs under them huh?

 

[bolly]

stacked

it'd all fit no problem kfa, but the wife would definately... throw a caniption-fit

 

[bolly]

side firing couch-subs!

originally had the dual voice-coils wired in series, changed that almost immediately to parallel and now they seem to be woofin a little better. Here's the rack;

 

[bolly]

do I ever have some listenin' plans for this today!

 

[Charivari]

do I ever have some listenin' plans for this today!

Hmm, so is that what I felt? I originally thought it was just a truck driving by, but seeing that you're listening to those Shivas, I wonder.

- JP

PS: Crank those babies up! :thmbsp: