# Cant get sound from my Marantz 7007 to my Behringer EP2500. PLEASE HELP..



## AutoDelphi (Jul 23, 2014)

Hey Everyone,

I have gone the route of external amp to power my Subs. I have a Marantz 7007 receiver and I'm trying to hook my Behringer EP2500 amp to it. This setup is being used for a dedicated home theater. 

I unplugged my working powered sub from the RCA jack, plugged in a XLR to RCA plug into the RCA and the XLR into the input 1 XLR jack. and NOTHING.. could not get any sound out of it.

Pretty much the same adapter as this one. http://www.monoprice.com/Product?c_id=115&cp_id=11509&cs_id=1150902&p_id=4777&seq=1&format=2 

Does the Marantz 7007 have enough voltage on the sub pre-out to put out a signal to the EP2500?? 
Do I need a booster of some sort? 
Do I need to have a "Y" RCA adapter and use both XLR inputs on the EP2500? 


I was thinking that it should just plug into the amp and play. 
I was using only the following mode Switching: (Also below is a link the the PDF manual)

1 Left
2 Left
3 Left
4 Right 
5 Right 
6 Right
7 Right
8 Left
9 Left
10 Left

http://www.parts-express.com/pedocs/manuals/behringer-ep2500-ep1500-owners-manual-42010.pdf


Is there a setting I need to change on the Marantz??? 

Any help would be greatly appreciated. My hopes were to Pre-Amp the whole system.


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

Are you trying to use the amp as bridged (mono), or as two-channel (e.g. with speakers connected to channels 1 and 2)?

Regards, 
Wayne


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## AutoDelphi (Jul 23, 2014)

Wayne A. Pflughaupt said:


> Are you trying to use the amp as bridged (mono), or as two-channel (e.g. with speakers connected to channels 1 and 2)?
> 
> Regards,
> Wayne


I am using the amp in Mono. Last night I was able to get sound out of the Amp and subs by turning up the sub gain on the Marantz I turned it up to +12db and its barley making any bass. 

The amp is at full gain and the subs are barley moving at all!! I am thinking that the voltage out is low. 

I have called Parts Express and they told me I need a Balanced/Unbalanced Converter. Please see below

https://www.parts-express.com/rolls...d-unbalanced-converter-35mm-rca-xlr--245-1062
https://www.parts-express.com/art-cleanboxpro-stereo-balanced-unbalanced-converter--245-868

My question is that I am going to be using 5 amps to achieve 7.1 surround sound. does anyone know of any Stereo Line Balancer's that have 8 inputs and outputs versus having to buy 4 separate line blaancers?


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

For now until we get this sorted out, turn the Marantz’s sub output up to max.

For starters, it looks like you have some or your rear panel switches set wrong. If you have switches 2 and 3 set to the left, you have limited the sub’s extension to 50 Hz. I doubt that’s what you want, so move switch 3 to the right.

Make sure you have the speakers connected to two binding posts on the back channel designated for “Bridged.”

For bridged, only the Ch. 1 input is used; looks like you’re doing that already, but the manual notes on P. 7 that _only the Ch. 1 gain control is used in bridged mode._ If you have the Ch. 2 gain turned up as well, it’s cancelling the input signal. I suspect this may be your problem.

The manual doesn’t specifically mention this, but for good measure I’d recommend turning the Ch. 2 limit and low-cut filters off as well – move switch 8 to the right.

If none of this helps, I’d suggest following the steps outlined in Part 7 of my gain structure article (link in my signature) to determine if your AVR generates enough voltage to drive the amp. If you find that it can’t, then you need to look into a signal booster. 

I doubt you’ll find a multi-channel signal booster, as professional audio has no use for such a device.

Regards, 
Wayne


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## AutoDelphi (Jul 23, 2014)

Wayne, thank you very much for your help... I was speaking to someone at a audio store today. They said that if I am running from my Home Audio Receiver to a PE amp that I should be using the high impedance 1/4 input on the amp and not the XLR input. Can you confirm this for me?

Thank you


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

Doesn’t make a difference on any amps I’ve used but I’ve heard it can make a difference on some. Try a RCA to 1/4” TS (aka “mono”) cable.

Regards, 
Wayne


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## AutoDelphi (Jul 23, 2014)

Wayne I have the problem "FIX". Thank you VERY much for your help. 

The solution was by adding a ART Cleanbox Pro. Now this solves the issue I have with 2 of my channels. The only other issue I have is that I am trying to run my 7.1 systems on external amps. The guy at the music shop said that I could us an ART T8 8 Channel Transformer Isolater instead of the ART Cleanbox.

Wayne do you know if the ART T8 will work for what I am looking for?

https://www.parts-express.com/art-cleanboxpro-stereo-balanced-unbalanced-converter--245-868

http://www.parts-express.com/art-t8-8-channel-transformer-isolator--245-8650

I welcome every ones input..


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

AutoDelphi said:


> The solution was by adding a ART Cleanbox Pro. Now this solves the issue I have with 2 of my channels. The only other issue I have is that I am trying to run my 7.1 systems on external amps. The guy at the music shop said that I could us an ART T8 8 Channel Transformer Isolater instead of the ART Cleanbox.
> 
> Wayne do you know if the ART T8 will work for what I am looking for?


Two of your channels? You have two sub outputs that you’re sending to a single input on the EP2500?

The ART 8 is a passive device. It will convert unbalanced signals to balanced, but it won’t provide any signal boost.

I’m not sure, but perhaps running the Beri bridged decreased its input sensitivity, thus requiring the signal boost? I have a hard time believing that a $1000 receiver doesn’t have enough voltage from the pre-amp jacks to drive your main-channel outboard amps. What kind of amps are you using? 

You have to keep in mind that boosting the AVR’s output doesn’t just increase peak output. It shifts the whole operating range up, _including the noise floor._ There’s no free lunch. That’s not a big deal with subs, but signal boosters on the main channels is a recipe for increased background noise. It’s really better to just get a receiver that has enough output voltage to drive the amps you want to use, or get amps that will operate with the receiver’s existing output voltage. This is all spelled out in my gain structure article, if you haven’t reviewed it.

Regards, 
Wayne


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