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79 Posts
Discussion Starter · #1 · (Edited)
so mosconi has a cool calculator of phase degree it's called phac(Phase Control shortcut and it is awesome.
this thing basically adjust the phase degree for getting better imaging and more precise stage.
u can learn more here:

EQ, T/A, isn't everything if u tune a system countless of times u will found everytime the instrument or the vocal doesn't sound natural something is a little bit off, even though everything else is perfect, the solution is for this situation.
most of the helix line up u have phase degree, most of the people don't use this option cuz they don't know how.
This is basically the secret sauce, the last 10% you can get from your system.
This is the closest u can get to FIR.
I was in shock after i tested this method, try and see for yourself, The stage got perfect and i mean perfect, all the sound became natural, the separation was spot on, it is the final destination.
This tutorial is an advancement tuning step, if u don't know all the other basics it won't help you.

So how we do it?
1. Download mosconi dsp tool.
2. Tune your system, Eq, Crossovers, Gains, Polarity check, ETC, (Don't T/A yet)
3. Open mosconi software and chose dsp with more Channels then yours dsp, my got 10 so i will chose aerospace 8/12, Chose work offline.
4. Import the setting from the Helix to the mosconi software - EQ and Crossovers.
5. this is the opne the freq chart
this graph calculate the phase shift after apply all the filter and the eq.
Computer Audio equipment Personal computer Font Screenshot

6. then chose the channel so u will see the phase and the phase which mark with red circles.
This is your starting point, before applying any changes, now you can close the cart.
Light Rectangle Font Slope Line

7. The order of phase degree is L + R separate and,
the woofer are our reference.
we start with mids-> woofers
tweeters -> mids
sub -> woofers
we chose "Phase Shifter"
Chose freq in the left i found that 400-1000 works the best but it depends on you settings.
Colorfulness Font Audio equipment Parallel Electronic device

8. The phac window opens, we will attached the mid L(ch3) to woofer L(Ch5) and so on, here u can see we got 81 degree change
WRITE THAT DOWN, everything the phac calculate write it so in the end u will import it to the helix/your dsp.
Colorfulness Font Screenshot Software Audio equipment

9.Then ch4->ch6(mids R to woofer R), Write that down and continue with the order from step 7,
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10. in the end the result should look like that:
All the even channels are the same and the odd channel are the same(1-2 degree doesn't matter)
* On the subs channel 7-8 i made a mistake u should correcrt the degree to the same, one of the woofer doesn't matter which so be aware, both 7-8 should be 49/59 doesn't matter which degree target u chose.
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11. U can check the cart and see the phase is much better(I moddify the graph so u could understand better, after 180 degree the graph start from the top).
As u can see 100hz-3k is look much better alot closer to each other which mean better stagin,
compare this to the graph from step 6.
Colorfulness Rectangle Slope Plot Line

12. Import the phase degree u write down though the process we just did.
be aware degree bigger then 180 decrease 180
let's say the calculator give you 250 degree shift so you import in the helix 70(since 250-180=70)
Plus the helix tend to make steps of 5.6 degree so chose the closest one.
Font Rectangle Audio equipment Parallel Screenshot

13. T/A the system, i found that the helix auto T/A works perfect after 3-4 tries, make sure to use a enough volume in the T/A to the bar will be green otherwise it doesn't work that well.
If u have another processor make it manual though REW of Smaart(Or if u short on money - OpenSoundMeter which is like smaart but free and have the thing u need for T/A) But pleaseeee don't use the lame distance caculator it will not give you anything other then disappointment , if you want top natch system make your T/A the right way.
It's what make nice system to amazing system, this is how we connect speakers and make then into sound, a real sound.
I know zapco HDSP also has the phase shifter and I'm think on chaning the dsp soon.
If u know how to tune and u miss something, this is it, the last mile.

If u have any corrections/suggestion feel free.
I don't know anyone else who does this trick other then me.
U will be amazed.

I wrote it before i got to bed so there are some mistake in the tutorial i will fix everything tomrow...

79 Posts
Discussion Starter · #3 · (Edited)
2 things..

1) you are adjusting phase based off of the electrical signal. To be honestly, I really didn't read through all of this, but based on what it seems like you are doing, you may be correcting something that is just not there.

2) you can (kinda) do this in the helix software already... see below

View attachment 347814
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1. it works for me... and all my people i know with Mosconi like the phac u can try it out.
it fix the phase shift made of the crossover and eq, plus it helps with the group delay so the result should be better sound stage.

2. I forgot about it i will check it but i don't think it will help u anyways.

Checked it and it is not possible though the helix allpass display.

A demo of how it works with smaart:

79 Posts
Discussion Starter · #6 · (Edited)
1. PhaC can work
2. The frequency you put in shouldn't be an arbitrary frequency, but the crossover frequency from the drivers you want to align, f.e. when aligning midrange to midwoofers you choose f.e. 300Hz., for tweeter to midrange you type in 3000Hz (when crossing at 300Hz and 3000Hz).
3. PhaC only calculates phase based on driver specific filters.
3a. If you use the group eq to be able to use 30 bands of EQ for each driver PhaC will not work as it doesn't use the group eqs for calculations!
4. when doing it the "Mosconi way" you have to basically set T/A right at the very beginning (with safety crossovers for midranges/tweeters) with a binaural mic, otherwise results of PhaC may not be that good. I verified that with Frank Miketta.

Reason for 4 is the following:
Frank Miketta rightfully says if you set T/A it's a constant as it accounts for distances and speed of sound for both passband and stopband before you set the crossovers, i.e. the whole range of frequencies of the drivers. Crossovers and driver specific filters alter phase then in the crossover region, but passband phase stays the same, so you only have to adjust phase in the crossover region to get good alignment. All the builtin calculations are programmed for use of a binaural mic basically.

5. you really need to measure and verify it, 'cause sometimes it doesn't really work acoustically (ask me how i know!).
I respect everything u wrote and I know that already, but I found this is the best method.
I know the mosconi way, tried is several time,
and I know that they say t/a first but I found that after applying the Phac the center of the stage shifts so you need to t/a again.
and I know it meant for the crossover points but you can utilize it the align the phase as you wish and this works perfect, I don’t tend to follow the line, but try things for myself.

and for me and all myfriend the Phac works.
If you don’t know how to t/a or basic steps of tuning it won’t help you. But it give you some extra if you do.

5. When I will found free time I will try to measure it you are right, but I can ear it for sure.

79 Posts
Discussion Starter · #8 ·
Yea I agree and this was my original though that it won’t help and you should adjust everything using Smaart which there you can see the impact of the acoustic environment on the phase very precisely.
But I’ve tried it and found that it works, so you can try calculate everything into you head, but something the realty is different.
I want some one with experience to try it and then check the impact it has.

79 Posts
Discussion Starter · #12 · (Edited)
Yea I know JL Tun is awesome this is based of smaart files, confirmed by a friend that works at JL, the licences to implante it cost them a lot.

and to cathul that is why I recommended t/a afterwards cuz the stage shifted from the center To the side from me. I’ve tried all Marks methods and I like him a lot, he is a crazy meniak, but this is just my personal preference.

and yes this is faster and more easy then tries various phase degrees.
If you have the time you can make it better? Absolutely, but this method seems to give me the best stage I have had plus u can done all the tuning in less than 2 hours with it.

anyways there isn’t any decent staging guide over here so I think it can be really helpful.

79 Posts
Discussion Starter · #14 ·
If the phase on any driver is less than the driver you want to alter it to it wont work.
In your example if subs phase is -59° and woofers phase is -49° in phase you cannot use PhaC to adjust the sub to the woofer, but only the other way around, i.e. woofer to sub.
yep this guide is not dummy-proof u need to use your brain in some cases.

79 Posts
Discussion Starter · #20 ·
This is why I just do it by ear and rta
And this is why I made this guide - for people without trained ear.
Without 10 years experience.
Now they can make it too…
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79 Posts
Discussion Starter · #26 ·
But as dumdum and I both said, you are "correcting" based on the electrical signal, which may not be correct acoustically.
I heared that and I’ve answered to that already, check my comments…

79 Posts
Discussion Starter · #29 ·
Admins can u delete this thread?
Seems nobody try it and everybody sure that it is not working without trying…
So if it isn’t helpful delete it.
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