Rockustics BP Sub Jr - Question about powering this beast. (1 Viewer)

[hellspawn69]

I have a Rockustics BP Sub Jr-

http://www.rockustics.com/products/subwoofer-series/bp-sub-jr/
(2) 4Ω
Drivers
10" woofer
Power
300 Watts per driver

It has (2) sets of inputs, they are bridged together with a piece of metal, I believe it ships this way from the factory.


i want to power it with this (don't judge me, hopefully just temporarily...)

http://www.crutchfield.com/S-1SdDasmg2vt/p_156STRE945/Sony-STR-DE945.html
110 watts x 2 (stereo) into 8 ohms (20-20,000 Hz) at 0.09% THD — or 110 watts x 5 in home theater mode


I am going to take the LFE (Sub) out from my Sony DA4600ES and feed it into an input on the STR-DE945.

My question is, how best to run the speaker wire from the STR-DE945 to the Rockustics Sub? I know this is a bit of a rig, but I want to try this out before investing in an amp for it.


The STR-DE945 has a note on the back-

A or B: Select 4 ohm for 4 ohm or higher speakers. Select 8 ohm for 8 ohm or higher speakers.

A + B: Select 4 ohm. USE 8 ohm or higher speakers.


How can I get the most power out of the STR-DE945 to the Rockustics?


My hope was some way to bridge like the front A+B Left to one input on the sub, then the front A+B right to the other input, but something tells me thats asking for trouble. I'd rather not damage my receiver, but I'd REALLY rather not damage the Rockustics.


Thanks for any idea's / input.

Yes, I know, I need a real/good amp for the sub, but humor me.

 

[Robert_J]

Your sub isn't bridged. That's just a jumper between the drivers. Depending on how it is connected they may be in series or parallel. More than likely in series.

You can't bridge 99%, of the home receivers on the market so don't try it with yours. Connect one channel of your receiver to one driver. Repeat for the other driver. Use the volume control like a gain control. When you get the cash then you can get a real amp and real sub's.

 

[Al.Anderson]

You can't bridge the A/B, as then you could only use 8 ohm speakers. If you go with just the A channel, you can do this, but you'll have to use the 4 ohm switch and that will reduce your overall power (it just lowers the voltage so the amp doesn't draw too much power).


If you already have the 945, then it' work for a while; but if you're buying it, you should get one that can fully handle a 4 ohm load.

 

[hellspawn69]

Thanks for the input.

I already own the 945, so I did hook it up (as a temporary test), 1 channel to each driver input on the Rockustics with the metal jumpers removed.

It works, but I wouldn't say it works well (either that or this sub isn't as good as I had hoped, but I'm guessing it's cause I was tossing so little power at it). Still added a nice bit of bass and depth to my outdoor music, but I think I need to try and find an amplifier that will push ~600 watts and connect it to the Rockustics Sub with the jumpers in place, or a 2 channel one that is about ~300w per channel and do them individually.

Using the Sub Out from my main receiver should avoid any need for another EQ or anything like that.

Any suggestions on a Cheap amp that will fit my needs?

 

[hellspawn69]

Would an amp like this work maybe?

http://www.behringer.com/EN/Products/A500.aspx

 

[schan1269]

Yep

 

[hellspawn69]

Ordered this instead. http://www.crownaudio.com/en/products/xls-1000

Hopefully a better fit for the setup I have.

Seems like a better amp, more features,etc.

 

[ArmSC]

That Crown will work just fine too...probably what I would have bought to be honest.

 

[hellspawn69]

Should show up tomorrow. Gonna temporarily hook it up to test it. Hopefully a night and day difference from my initial 'rig' test with the old receiver powering it.

If it works great, I will have to order some 10 guage speaker wire probably, as my speaker wire follows a pretty long path to get outside my house to the backyard.

Not sure if I should hook it up with the amp bridged, and the jumper reinstalled on the sub, or just one output to each driver, might try both ways and see if I can hear (feel) a difference.


Thanks for all the info and advice so far everyone.