# HIgh Level Inputs on HT Subs



## drocpsu (May 3, 2005)

I have a random question about the high level inputs that you see on plate amps for HT subs. In my gameroom, I have an old Kenwood receiver that doesn't have a low level sub out. My HT sub has high level inputs, but not outputs (odd...). My only option to hook it up is to wire the sub with my main LR speaker outputs along with my speakers (which would be wiring it in parallel). 

This is how the manual recommends wiring the sub as an "alternate" method if it's not possible to wire Receiver -> Sub high level inputs -> sub speaker level outputs -> speakers. Since my sub DOESN'T even have the speaker level outputs....this is my only option.

I'm trying to figure out what kind of a load the amp would see from the sub. I just wonder because it's not actually wiring the speaker to the receiver...just the amp input. 

My speakers are already a 4ohm load for the receiver, and I'm just wary of wiring something in parallel and overloading the receiver.


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## 60ndown (Feb 8, 2007)

try it for 20 minuets and see if the amp gets hawt.


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## Guy (Feb 16, 2006)

The ohm load won't change much either way- The signal isn't being used to drive the sub- the plate amp is doing that, so no real increase in load.


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## Spasticteapot (Mar 5, 2007)

G Rahn said:


> The ohm load won't change much either way- The signal isn't being used to drive the sub- the plate amp is doing that, so no real increase in load.


Some subwoofers do not have internal amplification - however, since this one has got a power cord sticking out of it, I would wire it in parallel. Odds are that the speaker input is connected to a pair of 1,000+ ohm resistors, taking a low-level signal from the high-level output without putting any load on it.

If you're worried, you could plug in just the subwoofer and check the current with a multimeter.


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## drocpsu (May 3, 2005)

Thanks for the input. I tried it out and it works so far. I'll just have to see if the receiver gets hot or anything while I have it playing during longer periods of time.


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## Xander (Mar 20, 2007)

The high level outputs on plate amps are in parallel with the inputs. They're internally connected together, so you're doing the same thing by wiring this way, you're good. You're essentially putting a huge load (thousands of ohms, possibly megaohms) in parallel with the speakers, so it isn't changing the load on the receiver to any noticeable degree.


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