Axiom Home Page Forums General Discussion Home Theater Setting up my subwoofer

I should start a thread on measuring phase and walk you through it.

Measuring spl at a given frequency can get you phase aligned, but you would be extremely luck to also be in time with the same cycle.

You need to measure using a difference tool or transfter function tool to time align,

Mojo’s breakdown is terrific btw for his setup routine. Not how I would do it, but pretty clever with your sub setup. I think speaker outputs to subs hancuffs your options a bit, but I get your strategy for sure. Pretty well thought out. Thumbs up!

It would be interesting to hear what the difference dialing in phase sounds like. What results are you expecting ... room smoothing? Better efficiency? .... Also how to do it with multiple subs.

Like clean bass without overhang. Best outcome is you can run the sub level much hotter and it still sounds incredibly clean and sharp. One of those tweaks that makes a big difference with no cost.

That's a great description, Trevor. What a difference between my 600v2 and v4 subs. I can turn them right up with no loss of satisfaction. The v2 couldn't satisfy me no matter the volume.

Yeah Mojo, the mids lows on the 600 are why I love it so much. I was able to audition a 16" sub which was fun but it was a like laying in one of the those 25 cent Motel beds that vibrate... it's only good at one thing. This 600 for me is like a modern day massage chair lol. It plays best where it matters most and can still dive deep.


Is anyone else on here using REW? I've just figured out full range speaker measurements, about to start working on sub measurements. It's really good fun to compare science (SPLs) to what we think sounds good. Using REW has really made me work my room more than work my speakers (position & EQ), in fact, getting new windows now, lol, along with window treatments, and working on solutions for the fireplace.

Wow! You are really getting into this. How cool.

Trevor, look forward to your methodology on aligning phase ... I’ll have to try it and see if I can hear the difference. In the mean time I’ll google around and see if I can find some info on what’s happening and why it matters.

Download this app and purchase the Transfer function plugin. Round trip is around 100$ I think. I can walk you through it after.

https://apps.apple.com/ca/app/audiotools-db-sound-audio/id325307477

Here is the Transfer function Tutorial vid

https://youtu.be/Fbk9QLEwdZU

I have learned more from using this software and understanding sound than $100 could ever advance my system for sure (spent on gear or other items or tweaking by guess or by ear.)

You will need a long 1/8” jack audio cable to use to send test tones from the app to your equipment. Like this.

https://www.amazon.com/AmazonBasics-3-5mm-2-Male-Adapter-Stereo/dp/B01D5H8M18/ref=sr_1_3?crid=1SMKW2F4P31XS&dchild=1&keywords=1%2F8+to+rca+cable+25+feet&qid=1601507054&sprefix=1%2F8”+to+rca+cable%2Caps%2C185&sr=8-3

There may be other software suites to do this, but I have used this many times in different setups and it is fast and reliable. And just works.

I can now phase align at the cross-over by ear. My ear is now an acoustic synchroscope.

Unfortunately I only have this super-power in my right ear. I have to now train my left.

I'll be truly proud when I can do this to any tune rather than a sine wave.

If you like it leave it.