Advice on tuning ASW750 sub

[bigburner]

I own a pair of CDM9NTs and a single ASW750, configured for 2-channel audio.

If I take the specs for the CDM9NTs, how do I work out the optimal low pass frequency setting for the ASW750?

[bigburner]

Having had no feedback from this forum I've done some research and this is the result.

I've wired the ASW750 so that the output of the pre-amp goes to the input of the sub, and the output of the sub goes to the input of the power-amp. This enables the high-pass filter on the 750 to limit the frequencies being sent to the CDM9NTs to 80Hz and above (this is pre-set on the 750), thereby taking bass load off the 9NTs. I've set the low-pass filter on the 750 to 80Hz so that the sub only plays 80Hz and below. I've found that this results in the best stereo image because the sub isn't duplicating frequencies being played on the 9NTs.

Earlier I wrote to B&W to seek their advice. They suggested I set the low-pass filter to between 60Hz and 80Hz. In my opinion, at 60Hz this would mean that no frequencies between 60Hz - 80Hz would get played out of any speaker, effectively leaving a large 'hole' in the sound. If anyone disagrees with this assessment, I'd really like to know.

Putting the techie stuff aside, I have to say that the 750 has made a big improvement to my system. Real bass at last. How songs are mixed is a current interest of mine, and I now have a system that is far more revealing in that regard. Slow Blues in 'C' by Alvin Lee sounded like a new song. Overall a great upgrade.

[Ash]

bigburner,

I'm sorry that you didn't get feedback, but it seems that things are slow here these days.

I don't have much knowledge about sub setup, but I'm in the search for a sub right now. However, I was always interested in the topic of sub set-up because I could never get good bass from my current sub ASW1000. So I decided that I want to change the sub and go for either ASW 750 or ASW 825.

Anyway along my sub search I came across this sub set-up guide. I hope it helps, and if I had better knowledge of subs I would have gave you my comments.

http://www.audioholics.com/techtips/setup/loudspeakers/bassmanagementbasics.php

You will find a few links to sub articles here. It looks very detailed. I didn't get a chance to read this because I'm very busy these days. Tell me if you found it helpful.

One more thing did you compare the ASW750 to other subs??

[bigburner]

Ash, I listened to the 850 but it was out of my price range. The 750 and 850 were the only two models that my B&W outlet had connected. In New Zealand the 750 costs only 33% more than the 675. The 750 looks like a bargain compared to the closest models in the range.

Thank you for the set-up guide. I'll read it after I escape this forum!

[Ash]

How did the 750 compare to the 850?? Was there a significant difference?

[bigburner]

Ash, the 850 was set up with a pair of 800 fronts, and I was drooling so much over the 800s I hardly paid any attention to the sub. Sorry!

[BlazeMaster]

probably not as much difference as say 703s compared to 800s.