Hi, I've got a few questions about pre-outs. I'm thinking about amping a passive sub with a power amp which I run from the pre-outs of my receiver. If I do this, can I still run the mains from the receiver as usual? Is the amount of power drawn from the preouts small enough that it won't over stress the receiver? Thanks for any explanation...
ew, in fact, no you cannot do that if it is a stereo receiver. You have to pick and choose, the pre-outs will bypass the power amp of the typical receiver. However, if the receiver has a tape loop, you can split the pre-outs and re-feed the receiver in parallel to the sub's amp. I did this with a H/K receiver, but the input impedence was off, so I added an inline bias adjustment. This was 10 yrs ago, newer stuff might be different. your mileage may vary.
The receiver also has two sets of stereo pre-outs. However, I can locate no main in. Any idea why there are two sets of outs? Why would there be no "in?" I love the sound of this thing, but it's not the most convenient piece of gear.
hehe, eug, the good stuff is not usually 'convenient'. Your dual pre-outs make this a great starting point. Take a pre-out pair into the inputs of a stereo amp, or mono blok amps. You gotta find out if the passive subs have an XO. Pull the interface plate out of the sub and look for an XO. This one should be easy. What is the amp for the sub? And all relevant info, lay it all out for us.
400dB could probably d...,
SouthWest Mi...
Too Many DBs...
Post Number: 907 Registered: Dec-06
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YEAH! A 20,000 watt amp into 31 ohms! That should drive you sub pretty hard, or you tweeter! Omg our power is fluctuating like crazy and everything is turning off and on again and again. BYE!
ok- the sub has no crossover. It is an NHT sw1s- their bottom of the line a few years back. It also has only one pair of binding posts. you can't run into it then out to the mains. I have not bought an amp for the sub. But once I do- I may have to buy abnother for the mains, right? Help me through this one if you can. Bear in mind I want to buy as little additional equipment as possible. Thanks
ew, the pre outs from your receiver go to the aux inputs of another reciever, or the input for a power amp. The outputs of this 2nd amp go directly into the sub. You can either a; just run full range into the sub, or b;run an active or passive XO.
Noting your $ involved, just run full range into the sub for openers. The coil of the sub will kill the highs.
Note 'this is for openers'. I ran like this for years with Tecnics 12" dual subs, it worked fine.
Thanks- but how do I run the mains if i run the sub off the pre out? do I need a designated power amp for both? and what makes an active cross over "active?" thanks again
The second set of pre-outs will not affect themains at all. The pre-outs(good) will offer a way to add amps. You are only adding an amp that does bass. No sweat. The XO should be easy, just a coil for frequency response, but try full range to start. Gotta start somewhere. BTW, if you have to start with an external amp anyhow, Eugene, start with a cheaper receiver with a sub-out. More to follow.
Thankyou Nuck- But earlier you mentioned that If I ran anythign of the Pre-outs, it would bypass the power amp in my receiver. Are you saying that the second pre-outs will not do this, but the first will?
can I run from the pre-outs to the "aux input" on another reciever? How do I bypass the pre-amp on the second receiver if it doesn't have ins for the power amp? I've got an old lafayette receiver that should do nicely as a subwoofer amp, but its got no power amp ins. thanks