High and Low Pass filters on Preamp- help!

[phileserver39]

Howdy Fellow ARians,

I have a B&K Reference 50 preamp that I am still learning how to use. It has functionality allowing customization of the crossover frequency, low and high pass gain as well as the LFE level.

I am having trouble understanding what,exactly, these settings do and how to set them. I understand that my particular room set up plays a big part in this but I was hoping to get some basics so I can at least make a better educated guess on a starting point

My powered sub is connected to the sub out of my preamp. I am running a pair of Allison Four front speakers connected to my NAD 2400 THX amplifier, an Infinity Center connected to my NAD 3150 amplifier (bridged to mono out) and two powered M-audio monitors for my rears. I think I understand that the crossover frequency setting on the preamp dictates the cutoff frequency to the sub- any Q higher than what is set on the preamp will not go to the sub.

However, the high pass, low pass and LFE gain settings have me confused. Would these only apply if I was using a crossover on my sub while sending the higher frequencies from my sub to my front channel amplifier?

Any knowledge and advice is extremely welcome!

Thanks for your time and expertise.

J

[Mr Peabody]

I'm not familiar with B&K's set up. The processors I've used, keeping to basic set up, nothing customized, the high & low pass generally only kick in if your rears, mains or center is set to "small", the filters control what frequencies go to the sub and what goes to the speakers. From what I understand you keep your sub crossover set either to "bypass" to take it out of the circuit or turn it all the way up, the LFE is controlled automatically by what's encoded on the movie soundtrack. So if your Infinity center was rated to play down to 90Hz, and, if set to "small" as it should if it was really rated at 90Hz, you'd begin with your preamp crossover about 90Hz to see how it sounds and maybe go up or down depending on how it sounds to you. What I said is strictly for movies, I don't use my HT processor for music. Sometimes I do use the HD radio for background and found I had to choose a setting "both" in order for the sub to work for stereo.