# Wiring Help For Multiple Sub Amps



## cjdriver79 (May 28, 2009)

I think I may be having issues with the line levels going between my sub amps. I'll be honest some of the systems I've been reading about here probably cost more than my Jeep, but I've collected an assortment of components throughout college. 

My question is whether I need some sort of line level amplifier for my system. I'm taking the Sub Out on my main Amplifier (HS-3000 Technical Pro) and running it between 2 separate subwoofer amps (LX-3000 Technical Pro power amp & a Sony AV1020 receiver). My big issue is that the LX-3000 is powering my 15" and it seems that I have to really crack up the knob to hear anything. 

Is it possible that there is a line level drop because of the split and the amplifier isn't receive the line signal lvl it should? 
Also are there any cheap line level boosters someone could recommend that could supply the appropriate levels to all my components off of 1 line out? I would need roughly 1 input & 4 output. 

Another random Q. Can anyone recommend an inline crossovers to cut all mid/highs and leave only the bass? It may be a "Sub Out" but I think there are still high Hz sneaking through.

THANKS!
Bob
(Sorry about the huge post...) :duh:


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## Sonnie (Apr 11, 2006)

Hi Bob...

I am not familiar with those amps, but I am confused about how you have them connected. It seems like to me you would use the sub pre-out on the Sony Receiver, assuming it has one, maybe it does not.

You might also measure the response of your "Sub Out" to see if the HPF is as you set it, assuming again there is a way to set it.


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## cjdriver79 (May 28, 2009)

The HS-3000 is a Hybrid Power Amp that is basically just a 3000W Stereo Receiver. That is why I am using the Sub Out on it. The Sub Out is also adjustable on the HS-3000 so I'll check it to compare with the others. I had assumed that since my 2 power amps are the same brand that they would have the same levels.


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## Wayne A. Pflughaupt (Apr 13, 2006)

cjdriver79 said:


> Also are there any cheap line level boosters someone could recommend that could supply the appropriate levels to all my components off of 1 line out? I would need roughly 1 input & 4 output.


Something like the Behringer Xenyx 802 should work. You could use the main two outputs, plus the two control room outputs, to drive additional amplifiers. 



> Another random Q. Can anyone recommend an inline crossovers to cut all mid/highs and leave only the bass? It may be a "Sub Out" but I think there are still high Hz sneaking through.


Behringer, Ashly, Rane etc. all make electronic crossovers.

Regards,
Wayne


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## greyleopard (Jul 14, 2009)

This issue has been driving me crazy for years. My receiver has two subwoofer outputs. My manual says if I use them both, the signal IS cut in half. Now, I've read countless responses to this question on many forums. Most state you can split it out. The reality is, not on my amp you can't. At least not without losing signal strength. I'm running 4 LFE devices and have tried splitters, and numerous distribution amps. The distribution amps definitely work better. However, I can't find any with a response that drops below 20Hz. Somebody please tell me there is a product that will do this!


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## greyleopard (Jul 14, 2009)

Found one, maybe? RDL has an unbalance audio distribution amp with a freq range of 5hz to 50Khz. I've ordered one so we'll see what happens.


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## Anthony (Oct 5, 2006)

If you are splitting to two of the same amps, you can count on halving the output (-3dB) going to each. However, this math assumes you are using two with the same input impedance. If the input impedances don't match, then one amp may get more signal and the other may drop more.

Also, if both amps have lower than normal input impedances, you may be current limited (the amount of current in the signal line) going out of the preamp. Unlikely, but possible.

Some subwoofer amps allow daisy chaining the signal, presumably bumping it back up to line level before sending it on (otherwise it's just like an internal splitter at the RCA jacks). Sadly I don't know of any line level amps that guarantee lower than 20Hz frequency response.


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## greyleopard (Jul 14, 2009)

I just found a distribution amp that is specified to reach 5Hz. The company is RDL. It is a stereo but can manage as 2 mono inputs with 4 outputs each. They have a balanced and unbalance version. I'm going to try it.


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## cjdriver79 (May 28, 2009)

I think I found the RDL you had mentioned. Was it the ST-DA3 Line Level Distribution Amplifier - 1x3? http://www.rdlnet.com/product.php?page=38 is the link. 

Maybe I'm confused, but do they have this listed as needing 24V?


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## Anthony (Oct 5, 2006)

Yes, it needs DC power to operate. A regulated wall-wart would probably do it.


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## greyleopard (Jul 14, 2009)

I bought the RU-UDA4. It has the RCA connections. The transformer is extra if you don't have one. I keep old transformers and have about 100. Oddly enough, I didn't have any with 24Vdc output. I purchased one from Radio Shack. If you know you don't have one, just buy the RDL transformer. The disti amp only pulls 25mA, so anything with higher out put should work. If your not using the transformer to power anything else, get as close to the 25mA current as you can to keep the Voltage from running over 33V. They say a 12V will work, but I wanted to make sure I had the power I needed.

BTW, the RU-UDA4 is working fine.

Charlie


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## Andysu (May 8, 2008)

Let’s assume the active subs above are passive okay. Use the straight forward AVR/AVP send its LFE.1 track output to DCX2496 with both units playing the same signal then route off the LFE.1 to the assigned multiple amplifiers for amplification.

Use the basic nine band parametric EQ on the outputs of the DCX2496 to adjust each sub for smooth frequency response. Use the audio limiter to prevent level exceeding into clipping. Here you’d have many options and the cost with most Behringer products won’t cost the Earth, the rest you’ll have to figure that out because I can’t make money grow on tress as of yet.

Now you have the ultimate power in the universe. . I suggest you use it.:hsd::bigsmile:

Only thing is the DCX2496 nor will any of the DSP1196P FBQ2496 EQ below 20Hz. You could put low pass filter in place for each sub and still option mindless head banging wall plaster quaking rumbles to put your home on demolition list as deemed unsafe to live in due to the structural damage.:rofl2:


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## cjdriver79 (May 28, 2009)

Update:
So I've given up on combining my amps. The difference in brand names has made it virtually impossible. Instead I purchased a vintage Pioneer Elite M-91 and just split the input off my existing amp to feed it.
Sounds amazing running to the Fosgate 15". Only downside is the M-91 will only go as low as 60Hz 

Living in a fraternity, and having such a small room, I've made my neighbors start taping down everything they put on their shelves so it doesn't rattle off. 

Thanks for all the input. :yay2:


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