Axiom Home Page Forums General Discussion Home Theater dazed and confused

okay well today was the day i was going to pick up my denon 3805. well to say the least i didn't get it. worse thing is now i'm more confused then i was when i was deciding which receiver to upgrade too. okay heres my story well i went to the store to buy my denon. while i was waiting for salesmen i started to look around. found myself over by the ht receivers. well to say the the least thats when i got confused. sitting there by the receivers was an onkyo 2 channel power amplifier. its power rating is 2x100 in 8ohms and 2x125 in 6ohms. so after seeing this my brain goes into overload. the price is even better, only 350cdn for it. that means i could by 3 and still be a grand less then the denon reciever. also this would give my m60s 200 watts each and the vp150 and qs8s would be running 250 watts each. so this is how i became dazed and confused. so i drove home not nowing what to do. then realized my m60s have two sets of binding posts. so then i went to look for there instructions but can't find them. so now i'm really confused. so my question is what should i guy do. and how do you hook the amps up to your receiver so they both run power to the speakers and get the 250 and 200 watts there. please someone help.

I think you misunderstood the amp ratings. 2x100 means 2 channels at 100 watts each. So your fronts would get 100 each, but you 6 ohm center and surrounds would get 125 each. In order to use these with your current setup, your receiver needs to have pre-outs for all 5 channels.

Also, powering the center only requires one amp, so if you got the two channel amp, one of the channels would go unused.

no i understood the power rating i might have mis worded it. what i'm saying is my onkyo reciver as is runs 100 watts in 8ohms and 125 in 6ohms. so by adding these amps it would be 200 and 250 watts. it would give an extra 100 watts to the m60ti's and 125 to the 6ohm speakers pushing the channels to 200 and 250 watts. but my question is do you bi amp them or what.the m60ti's have two sets of binding posts the qs8 and vp150 don't so how do you get the power from the av receiver and the amp to those speakers.

>>so then i went to look for there instructions but can't find them. so now i'm really confused. so my question is what should i guy do. and how do you hook the amps up to your receiver so they both run power to the speakers and get the 250 and 200 watts there

That's what we call "faux bi-amping"

With "real" bi-amping you use an electronic crossover before the power amp to separate out low & high frequencies (around 200 Hz for M60s, I think), run low & high to separate power amps, then run the LF power amp outputs to the woofer binding posts and the HF power amp outputs to the mid/tweeter binding posts... after disconnecting the little brass jumpers of course. One of the nice things about "real" bi-amping is that the LF amp normally clips first, but if it clips you get a nice rich fuzzy bass sound while your high frequencies stay clean... rather than having the high frequencies from the clipping amp go into your tweeter and fry it.

Since you probably don't have one of those electronic crossovers (and the x-over in your receiver won't cut it), all you can probably do is run the same signal to two power amps, for each channel, connect one power amp to woof and the other to mid/tweet BUT BOTH AMPS CARRY ALL THE FREQUENCIES so you don't get many benefits.

A more common use of the two binding post sets is "bi-wiring", where you have one power amp output with two sets of wires running off it, one going to each set of binding posts. Benefit is generally felt to be.... um... is "placebic" a word ?

Unless the amp is designed for bridging (something totally different again) I wouldn't plan on getting 200 useful watts into a speaker out of a 2x100 watt amp.

What is your current receiver again ?

also its a 6.1 system so all 3 amps would be running one set of speakers. fronts to one surrounds left and right to one, and the center and back surround to another. yes the receiver has pre outs for this. but how do you hook it up i know you have to use cables to run from the receiver to amp. but the wiring is what confuses me. if you only wire from the amp then you lose the power of your reciever. so what do you do. do you just run two sets of wire one from the reciver one from the amp and then twist them together and insert them into the binding posts. see this is why i'm confused.

Short answer :

No. Don't go there. Step away from the amplifiers.

Normally when you get a power amp you DO lose the power from the receiver, ie you are essentially replacing the power amp built into your receiver with a bigger and better one.

This is why you don't see anyone buying a 100 watt amp if they have a 100 watt receiver. More common is something like a 65 watt receiver with a 250 watt amp.

One other point -- it's pretty common to just use a big power amp on the mains, since they are the most likely to be used full range and/or to cross over at a lower frequency and hence need more power.

One of the hidden benefits of amping a few channels is that you now have relatively more power supply available for the remaining amp channels in the receiver which ARE being used, so they are generally able to put out a bit more power while still sounding clean.

the receiver is an onkyo tx-sr701. so getting amps to boost the power is a waste of money then.

Not a 100W or 125W amp anyways.

One thing to remember though, when it comes to power rating for power amps, the numbers are usually more true than power ratings for receivers.

That said, the jump from a 100wpc receiver to a 100wpc amp, is probably not worthy enough for the cost.

so if a guy isn't going to be listening at high levels where the reciever would clip out theres no need for the connecting of more amps. i've seen other amps also like multi channel amps from rotel. what are they for then are they just to power speakers, and then you just buy a reciever with no wattage to process the sound.