Subwoofer phase settings

[BIGBERNARDBRESSLAW]

I've had my Tannoy TS2.10 for quite some time, but I wasn't 100% sure if I had it setup properly, so I've spent a bit of time, checking I had it connected correctly, and that I had all the levels where they should be.

I'm almost happy, but there's just one thing that's still leaving me a bit confused. The receiver (Yamaha RX-A2020) has a setting where I can have either normal or reverse phase, and there is also a knob on the back of the sub where I can adjust phase from 0 to 180 degrees.

I'm presuming 180 is reverse, so what's the difference between normal and reverse phase? If I choose normal on the receiver, should the sub be set to 0 degrees, and if I choose reverse on the receiver, should the sub be set to 180 degrees?

Your help as always is much appreciated.

 

[abacus]

Leave the reciever settings on default, and adjust the subwoofer phase control until it sounds its best. (There is no specific setting)

Hope this helps

Bill

 

[ellisdj]

There is a specific setting for sub phase.

The variable phase is there to stop cancellation between speakers and sub.

You adjust the phase to do this - you will never do this by ear you have to measure.
REW is free measuring software and is a worthwhile time investment learning how to use it

 

[eggontoast]

It doesn't matter which end you adjust either leave the receiver on normal and adjust the sub or vice versa, although the sub is probably variable from 0-180 and will give more control. As to which setting try it on 0 degrees then on 180 and see which gives the better response, it will depend on the position of the sub etc. All it does is changes the polarity of the signal with reference to the main speakers, this is to stop/reduce phase cancellation of the bass frequencies.

Where is your sub relative to your front speakers ?

 

[BIGBERNARDBRESSLAW]

Thanks to all for the information.

@eggontoast

The sub is next to a wall, just in front and to the left of my seating position, which is the only place (for now anyway) that it will go, so it's close to the rear left speaker, and a couple of meters in front of the front left speaker.

 

[his dudeness]

i could be wrong but i think in general you leave the sub on zero,amp on default and the avr sorts it out during callibration.

 

[ellisdj]

There is a chance an auto setup will use the speaker distances to put them in phase with the sub

I personally wouldn't trust that though

 

[Series1boy]

This is how I've set my focal sub with the Denon x4100. Set it to 0 on the sub and let your receiver sort it on the calibration setup. My sub is downward firing and is next to a wall and sounds mint.

 

[abacus]

Recievers vary in their auto setup caparbilities, howver most will adust the volume and time align all the speakers, but will not usually EQ or phase match the sub. (Hence the reason you have manual control on the reciever)

If you wish to get the absolute optimum for your setup then you can get a proffessional in who has the appropriate knowledge and equipment to optimise it for you. (Unless you are very knowledgeable (And most Hi Fi Buffs aren't) DIY calibration will be a hit or miss affair) In addition, most systems are in the lounge which can change almost overnight if someone dosen't like the furniture layout, thus rendering the calibration worthless.

Best just to let the auto setup do its job, then play some heavy bass and adjust the Knob until it sounds its best. (If you just have a phase switch then all it takes is a couple of minutes)

Hope this helps

Bill

 

[BIGBERNARDBRESSLAW]

Thanks all for the valuable information, I now understand what phase is, and what it's for.

I've left the sub on 0, and I redid the auto calibration on the receiver yesterday, and I'm happy with the results.

I rarely, if ever used the sub, which was possibly putting an un-needed strain on my main speakers (though I did like the sound), but I felt, as it's rated as a very musical sub, I should incorporate it into the system more. I've now set all my speakers set to small, and the main front and rears are set to 60hz. I've set it at 60hz, because I like the sound of my main speakers, but I just wanted to take a little of the strain off them, and I thought this would be a good point at which to do it. My small front presence and rear surrounds are set to 100hz. I know I'll probably play around with the crossover levels, but on the whole, I'm happy. I'm currently playing Miles Davis - Porgy & Bess, which is probably not the biggest test for the new setup, but I'll give them a good test later with some bass heavy music, and some noisy scenes from a couple of movies.

Thanks again to all.

 

[ellisdj]

Getting good bass and by this I mean properly good bass is one of the hardest things to do in most domestic rooms because the rooms murder it and yet its the most important factor

Without enough bass foundation a system will never sound right.

I have learnt this time and time again.

It's an area people should focus more time effort and budget where it's normally an afterthought after buying shiny boxes first

You get can get subs integrated much higher in the freq range which gives a fuller sound which to me is more realistic - i hate a lean sound its also a more punchy dynamic sound that once you have it there is no going back.

 

[Frank Harvey]

Just using five LS50s at the moment all set to large, without a subwoofer, although if I watch something with a crazy soundtrack (Mad Max remake etc) I'll set them all to small and crossover at 40Hz just to be safe. Listening level is generally around-25/-20dB, sometimes up to -15dB.

I can't say I'm missing the sub at the moment for a majority of the films, and I've been quite surprised how well the LS50s have been coping. It's interesting, with the speakers set to 40Hz, flicking between enabling the sub and disabling the sub how it affects the soundfield, and the general sound of what you hear. I find that with some sound modes as well - some just sound wrong, and some work far better than others.

With regards to sub phase, I've rarely had to touch it, despite the amount of systems I've set up over the years. I've certainly never had to use it in my own system at home.