Hi so I am trying to put together a 2.1 system for my computer. The problem I can't figure out is how to implement a subwoofer, and crossovers. Can I get an integrated amp with Sub out? I have seen some receivers and integrated amps with a "sub out" or "pre out" that are just MONO, no crossover. So are there integrated amps with a sub out and crossover?
Such as the NAD C 326BEE has sub out, but I can't tell if it has a crossover..
Any suggestions on integrated amps are appreciated. I will be using it for some 5" driver bookshelf speakers. Thanks
It somewhat depends on how you want your system to operate. Some media players have their own digital crossovers and you output this through a high quality sound card set up for 5.1 output.
If you are running this system from the basic audio outs on your two channel sound card, then, yes, you'll need some amplification in there. If a powered subwoofer is used, the sub's plate amp provides the adjustments you need and the front speakers are run full range. With a powered subwoofer the amp doesn't need to provide any crossovers.
My worry is that I will be sending the full range to the speakers. Wouldn't I be better off sending only say 80 or 100 hz and above to my Bookshelf speakers?
It again depends on how you want to operate your system. Bass frequencies require the most power/watts from the amplifier and typically result in the longest driver excursions from the speakers. With the former you risk driving the amp into clipping, which is bad. In the latter you risk driving the low frequency speaker system too far out of its safe operational range, and that too is bad. Generally, the best advice in audio is to not do things that are bad for the system. Literally, that's the best advice. When you hear distortion, turn down the volume. When you hear bass drivers begin clacking as their voice coils slam into the back of the motor system, turn down the bass. When your head hurts from beating it against the wall, stop doing that too. You know, the kind of common sense things too many people forget to do.
Otherwise, if your bookshelf speakers were intended for use without a subwoofer, then the designer should have built a system that is intended to see full range input. Most bookshelf sized speakers can't reporudce deep bass but they have no filters which are meant to remove deep bass from the signal path. They see full range signals and it is up to the user to understand the basic rules of audio which I laid out above. If it dstorts or makes noises it should not be making, stop doing what you're doing, turn down the volume and figure out what's wrong before you proceed. After all the years I have spent in shops with repair services I would say 95% of all service related issues result from user error or user abuse. This is especially true with speakers.
In terms of quality of sound when you are not running your bookshelves full range, that's somewhat a judgement call by you. The bookshelves will roll out the deep bass due to the nature of internal resistance inside the speaker enclosure and the driver can't overcome that resistance. Whether allowing the bookshelves to run full range or not is really a simple matter of trying the system both ways; with the filter action and without. Which sounds better to you is how you should run the system. And then, if you hear distorion or strange noises, shut the system down and determine the reason for the distortion or noise. More often than not simply playing the system at a slightly lower volume level is the answer.
If you integrate a subwoofer, you need to understand whether the sub's crossover filter removes deep bass from the satellite speakers. Not all sub crossovers will do this as it saves the sub manufacturer a few dollar not to. In that case, you would need a processor somewhere upstream - usually in the amp/receiver - which does filter our low bass from the satellites' input.