Incorporating MiniDSP With Audyssey XT32

[Pogre]

Umm, kinda. A house curve will provide a rising response from about 200hz to say 20hz(or wherever you want it to roll off. Usually +5 to 10. Not a lot unlike what deq does. I prefer one standard vs a moving target so... I am gonna try the offsets though.
Try home theater shack or google, house curve help. Really good info.

I'll check that out, thanks Bill. the last chard I posted, the hybrid, is that +/- 3db from about 120hz to about 15hz? Am I reading that correctly? That's really good, right?

*Edit:

If you really want to assault your brain, read the BFD user guide at HTS. It doesn't talk much(if at all) about minidsp, but it does talk about EQing your system. I think you'll be well served by reading it.

This too, lol

 

[shadyJ]

This is what I'm going with for now. I'm gonna get stuff cleaned up and put away. I have company coming over later to watch the fight.

View attachment 22025

I'm pretty damned happy with that. I can hear the difference too and loving it. 2 things Audyssey did that it's never done before. It made me turn the gains up on both subs (both are still under half way) and it set the distance for my subs at 17ft. It usually sets them at 13.9. that's not a complaint, I like the results. It's just way different.

*Edit: That's with no smoothing. I didn't even think to see what it would look like with a little smoothing.

That is a dream of a response. There isn't really much improving on that- that is flat. People with systems that cost many times that of your system do not have a response nearly as good. That looks to me like +/- 3 dB from 15 Hz to 125 Hz, and maybe even a tighter response than that. Congratulations!

 

[William Lemmerhirt]

Yes. It's a great curve. Me jelly!

 

[TheWarrior]

Wut? lol. House curve? Isn't that what I just did?

This is just the subs running to 150 hz right? I assume they will have a lower crossover, so you still need to understand the effectiveness of your selected LFE crossover, the coupling of the other woofers, and the influence of higher order resonances that may not have been corrected that start interfering with the midrange. You're doing it right by starting 'at the bottom', but there's a lot more to do yet!

 

[ATLAudio]

@TheWarrior
"the coupling of the other woofers, and the influence of higher order resonances that may not have been corrected that start interfering with the midrange."

Alex, you'll have to break down this Star Trek techno babble.

That said, based off all the graphs he's done so far, I'm fairly certain there's very little left to do. He can run a sweep of subs and speakers up to 300hz, add a tweak or notch filter or two if that.

 

[KEW]

That is a dream of a response. There isn't really much improving on that- that is flat. People with systems that cost many times that of your system do not have a response nearly as good. That looks to me like +/- 3 dB from 15 Hz to 125 Hz, and maybe even a tighter response than that. Congratulations!

What he said!
There may be some more tweaks you can do, but I feel pretty sure your system sounds better than at least 90% of people who have more expensive systems because of your tuning efforts!
Hopefully the fight tonight is mic'ed such that you will hear the sound of a KO falling to the mat with wonderfully perfect clarity!

 

[Pogre]

This is just the subs running to 150 hz right? I assume they will have a lower crossover, so you still need to understand the effectiveness of your selected LFE crossover, the coupling of the other woofers, and the influence of higher order resonances that may not have been corrected that start interfering with the midrange. You're doing it right by starting 'at the bottom', but there's a lot more to do yet!

Dude, I just barely learned how to get rew to produce a signal through the mini to both of my subs last night.

You're talking way over my head here. I think based on the graphs I've been posting, I've been making improvements almost every time. And based on the last one, I don't think there's much left to do.

 

[KEW]

This is what I'm going with for now. I'm gonna get stuff cleaned up and put away. I have company coming over later to watch the fight.

View attachment 22025

I'm pretty damned happy with that. I can hear the difference too and loving it. 2 things Audyssey did that it's never done before. It made me turn the gains up on both subs (both are still under half way) and it set the distance for my subs at 17ft. It usually sets them at 13.9. that's not a complaint, I like the results. It's just way different.

*Edit: That's with no smoothing. I didn't even think to see what it would look like with a little smoothing.

Question:
Is this with your subs plus mains or just the two subs?

At low frequencies, the plots without smoothing just don't get so jittery as the higher frequencies (you can see that in this chart as it is very smooth from 10 to 20Hz and starts to get crazy by the time it reaches 300)!

I'm betting if you took the speed of sound, calculated how long it would take sound to travel 3.1 feet, you would get a pretty good estimate of the duration of the miniDSP's ADC, internal processing time, and DAC!

 

[William Lemmerhirt]

Yeah, you'll want to sweep with the mains to see how the XO integration is. Remember the phase trough from earlier? Otherwise it's beautiful.

 

[KEW]

I prefer one standard vs a moving target so... I am gonna try the offsets though.

This really depends on what range of volume you listen to. The beauty of DEQ is it corrects depending on the SPL. You may tune a fixed house curve perfectly for your normal -20dB (for example), but if you need to listen at -35dB so you can hear the oven timer in the kitchen go off, it will lose a lot of the fullness of the bass. DEQ is designed to meter the frequency contour to compensate for level.

But for now, I'd recommend Pogre just "drink in" that smooth bass and enjoy the sound of it. I think it is a bad idea to implement too many changes too quickly - for two reasons:
1) Why not enjoy several "Christmases" instead having it all at once.
2) With time, each improvement yields a better trained ear for refining/evaluating the benefit of the next improvement.

 

[TheWarrior]

Dude, I just barely learned how to get rew to produce a signal through the mini to both of my subs last night.

You're talking way over my head here. I think based on the graphs I've been posting, I've been making improvements almost every time. And based on the last one, I don't think there's much left to do.

This is a graph of the subs only, yes? With the crossover set much higher than it would normally be, yes?

Then this doesn't depict your system response. It shows what the subs can do by themselves, but you can't see if the towers are effectively taking over, and what higher order resonances are doing to the upper bass and midrange. Knowing your room modes eliminates all the guess work. Which unfortunately is all Audyssey and REW can do without being told the dimensions.

I don't know what size your room is, but based on your acoustic measurements, I'd specified some rough dimensions that should be found somewhere in your space in a previous comment. Am I right? Then have some faith that some basic math can help determine where your subs are ideally placed with their own unique DSP filters.

It's not 'rocket surgery' but is well worth the effort! And I got tired of guessing.

 

[William Lemmerhirt]

This really depends on what range of volume you listen to. The beauty of DEQ is it corrects depending on the SPL. You may tune a fixed house curve perfectly for your normal -20dB (for example), but if you need to listen at -35dB so you can hear the oven timer in the kitchen go off, it will lose a lot of the fullness of the bass. DEQ is designed to meter the frequency contour to compensate for level.

But for now, I'd recommend Pogre just "drink in" that smooth bass and enjoy the sound of it. I think it is a bad idea to implement too many changes too quickly - for two reasons:
1) Why not enjoy several "Christmases" instead having it all at once.
2) With time, each improvement yields a better trained ear for refining/evaluating the benefit of the next improvement.

Fair enough Kurt. I will fully admit I haven't given deq much of a chance. At 0 offset, it provides a satisfying bass experience, but runs my surrounds too hot. Due to that I've just run my system without, even though I could trim them back probably. I don't have any playtime currently, but will soon and actually have become quite curious, and look forward to trying the offsets.
Pogre is having lots of fun, and getting great results. I think one the full range sweeps come in, and get fixed he will be in heaven.

 

[KEW]

So where are the subs in relation to the the +/- 25ft, 19ft, and 15ft walls?

These are his guesses of dimensions corresponding to your room based on your measurements.

 

[Pogre]

Question:
Is this with your subs plus mains or just the two subs?

At low frequencies, the plots without smoothing just don't get so jittery as the higher frequencies (you can see that in this chart as it is very smooth from 10 to 20Hz and starts to get crazy by the time it reaches 300)!

I'm betting if you took the speed of sound, calculated how long it would take sound to travel 3.1 feet, you would get a pretty good estimate of the duration of the miniDSP's ADC, internal processing time, and DAC!

That's without my main speakers, just the subs. I just finished taking several measurements at different crossover points with my mains and my subs. It ain't as purty, but still with no smoothing. Seems like the less my subs are doing, the worse it gets.

I tried to do a few with only a couple of sweeps at a time so it isn't so difficult to untangle. The last overlay shows the contrast between setting my crossover point at 40hz and 100hz. I labeled all of the sweeps to make it easier.

 

[Pogre]

This is a graph of the subs only, yes? With the crossover set much higher than it would normally be, yes?

Then this doesn't depict your system response. It shows what the subs can do by themselves, but you can't see if the towers are effectively taking over, and what higher order resonances are doing to the upper bass and midrange. Knowing your room modes eliminates all the guess work. Which unfortunately is all Audyssey and REW can do without being told the dimensions.

I don't know what size your room is, but based on your acoustic measurements, I'd specified some rough dimensions that should be found somewhere in your space in a previous comment. Am I right? Then have some faith that some basic math can help determine where your subs are ideally placed with their own unique DSP filters.

It's not 'rocket surgery' but is well worth the effort! And I got tired of guessing.

Posted up some more charts addressing this.

 

[KEW]

That's without my main speakers, just the subs. I just finished taking several measurements at different crossover points with my mains and my subs. It ain't as purty, but still with no smoothing. Seems like the less my subs are doing, the worse it gets.
View attachment 22026 View attachment 22027 View attachment 22029 View attachment 22030 I tried to do a few with only a couple of sweeps at a time so it isn't so difficult to untangle. The last overlay shows the contrast between setting my crossover point at 40hz and 100hz.

Audyssey?

 

[Pogre]

Audyssey?

Audyssey is on, DEQ is off. I'm liking the 100hz crossover.

 

[ATLAudio]

@Pogre
It looks like 100hz is a good crossover for you.

Put in a notch filter at 75hz, +5dB 5Q (guessing)

I don't see any reason to view without smoothing anymore, run it at 1/12th at this point and see how it looks.

 

[Pogre]

@Pogre
It looks like 100hz is a good crossover for you.

Put in a notch filter at 75hz, +5dB 5Q (guessing)

Okay! Now we're getting somewhere. That is as soon as I figure out how put in a notch filter...

 

[KEW]

Audyssey is on, DEQ is off. I'm liking the 100hz crossover.

Those towers really do look cool!