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Focus Fidelity Filter Designer
#81
I am excited to get started on this but my house is full of family for the holidays so I won't get a chance to even start until after January 1st.

@markush - My speakers don't have a SAM profile so that's not in the cards at this time.
Devialet 440 Pro (two 220s)- Oracle CD transport - Kuzma Stabi S/Stogi S turntable - Von Schweikert VR-35 speakers - JPS SC3 SCs - PI Audio power conditioning -
Triode Wire Labs ICs and PCs - Roon on NUC 8i7beh running ROCK
Durham, NC USA
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#82
Have to get a new UMIK-1 and looking forward to start testing.
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#83
Can you use this also for the parameters in Devialet when you do not want to use Roon? I have a turntable also.

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#84
You mean an „export“ from Focus Fidelity to Sweet Room file?
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#85
(22-Dec-2021, 08:44)markush Wrote: You mean an „export“ from Focus Fidelity to Sweet Room file?
Yesss

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#86
To pick up on some of the recent posts here.

@paul.oorbeek - Focus Fidelity Filter Designer creates convolutions which I believe are 65536 tap length FIR filters, and hence can perform "time domain" phase correction and more. This is far more sophisticated than the parametric equalisation as used by Sweet Room. So Sweet Room is basically a configurable graphic equaliser, FFFD is far more more sophisticated.

The simple answer is no, you cannot somehow export a Focus Fidelity generated convolution into Sweet Room, they are very different things and not compatible.

Is the CI board capable of running a FFFD convolution? I am not sure, but even if it was, this would need a firmware upgrade with Devialet support to integrate. As it happens, I too have a turntable and I would love to be able to use FFFD convolutions when listening to vinyl. Someone mentioned to me a while ago that one of the MiniDSP products can run externally generated convolutions. If this is correct, then it might be possible to run this together with an external phono stage and run the result into a Devialet amp. I would need to investigate further to understand if this is even possible, and if nothing else it is getting a little complicated. Something for another day. Similarly, I was reading about someone who runs his turntable into a PC running HQPlayer with convolutions. Clever stuff, but nothing like the joyous simplicity of just connecting your TT direct to your Devialet.

@markush - You were asking about SAM % levels when taking the measurements. So far, I have been taking my measurements with SAM on, but with the SAM % set to 0. My logic here is that I want SAM to perform phase correction for my specific speakers, but I do not want SAM to add any kind of tone control / bass boost. Consider that Focus Fidelity Filter Designer will adjust levels in line with whatever target frequency curve you set, you may end up with a situation where SAM is boosting specific frequencies and FFFD is cutting, so I think it is logical to leave the frequency balance and levels to FFFD.

I have tried frequency sweep measurements with SAM at various percentage levels. If nothing else this is informative. I know with my speakers the SAM % is only influencing bass levels at very low frequencies, only noticeable below about 30Hz. So maybe the best advice is to measure your own speakers in your own room at your preferred SAM %, and then with higher and lower SAM %, just to get an understanding of what SAM is actually doing versus what your ears hear and you think sounds about right. This might be useful information to know if you get to the stage of fine tuning your own frequency "target curve".

Another way to look at the above is to change the question slightly to "what bass and treble settings should I use when making my measurements, I quite like listening with +2dB on the bass". To this question it seems more obvious that you should set the amp's tone settings to flat / 0.0dB, and correct the tonal balance with FFFD, and here I think it is much the same with SAM %, which is essentially nothing more than a finely honed speaker specific tone control.

@mdconnelly - you wrote "The one thing I really disliked about trying to use REW was the difficulty (time, expertise, effort and doubt) in making such measurements in order to compare various changes in my system and room." - These words struck a chord with me, I feel exactly the same way about REW measurements. I do not like to say bad things about REW, it is free and it is incredibly powerful software that does vastly more than just take room measurements. But if the only thing you want to do is take room measurements, Focus Fidelity Impala is much easier and vastly more intuitive to use.
1000 Pro - KEF Blade - iFi Zen Stream - Mutec REF10 - MC3+USB - Pro-Ject Signature 12
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#87
@Confused ...

I wonder if the question that @paul.oorbeek asked wasn't more about using the new beta Focus Fidelity measurement software (Impala) as a means to help determine how best to apply equalization changes within Sweet Room. It would not be direct, but I suspect it would be quite insightful. But, to be honest, I've yet to give Impala a try so I may be mistaken.
Devialet 440 Pro (two 220s)- Oracle CD transport - Kuzma Stabi S/Stogi S turntable - Von Schweikert VR-35 speakers - JPS SC3 SCs - PI Audio power conditioning -
Triode Wire Labs ICs and PCs - Roon on NUC 8i7beh running ROCK
Durham, NC USA
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#88
(22-Dec-2021, 18:45)mdconnelly Wrote: @Confused ...

I wonder if the question that @paul.oorbeek asked wasn't more about using the new beta Focus Fidelity measurement software (Impala) as a means to help determine how best to apply equalization changes within Sweet Room. It would not be direct, but I suspect it would be quite insightful. But, to be honest, I've yet to give Impala a try so I may be mistaken.
Yes this also party of my question! Both thanks for the reply!

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#89
(23-Dec-2021, 16:46)paul.oorbeek Wrote:
(22-Dec-2021, 18:45)mdconnelly Wrote: @Confused ...

I wonder if the question that @paul.oorbeek  asked wasn't more about using the new beta Focus Fidelity measurement software (Impala) as a means to help determine how best to apply equalization changes within Sweet Room.  It would not be direct, but I suspect it would be quite insightful.  But, to be honest, I've yet to give Impala a try so I may be mistaken.
Yes this also party of my question! Both thanks for the reply!

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I mentioned in my earlier post that REW is very powerful and can do a lot more than the much easier to use for room measurements Focus Fidelity Impala.

I think this is the case with trying to optimise PEQ settings in sweet room. The link below was originally posted in the Sweet Room thread:

https://pbxbook.com/other/devialeteq.html

This indicates how you can use REW measurements to create PEQ settings that could then be used in Sweet Room. So you can do it with REW, but it is not exactly straight forward and intuitive.

What I do not know is if the EQ filter creator in REW would work with Impala loaded measurements. I do know that Impala measurements can be loaded into REW and viewed and compared with REW measurements in terms of SPL versus frequency, but the Impala measurement lose functionality versus "native" REW measurements.

Would Impala measurements work with the REW EQ filter creator? I do not know, but I might try some experiments to find out when I have some spare time.

EDIT: I have just tried loading an Impala created measurement into REW to see if it works with the REW filter creator. The good news is that it appears that it does. The bad news is that going back to REW, PEQ and individual frequency gains and Q's etc. seems to be extremely clunky and very hard work in comparison to FFFD. Also, Impala will generate multiple measurements for the left and right speakers. You can only use one measurement in the REW EQ filter creator, so only one left or only one right measurement in REW. A work around for this might be to perform the measurements in Impala with the Devialet set to mono. (which you can do by selecting the balance control on the remote) I am not sure if this messes up the measurements to a degree, but I guess it is ok for for making basic PEQ measurements.

So in conclusion, yes it will work, but creating far more sophisticated convolutions in FFFD just seems so much easier in comparison.

I remain convinced that for vinyl replay some kind of hardware solution that will actually run room correction convolutions is what is required, creating PEQ in Sweet Room just seems like too much hard work for what will ultimately be inferior results.

Consider that with Focus Fidelity, I can create a convolution, listen to some music and think, this has too much bass, or is too bright or whatever. I can then create a new convolution with a slight adjustment to the target curve, load this up into HQPlayer and be listening again in less than 10 minutes. Imagine just how long a similar process would take with Sweet Room, it would be very hard work.

So, is there a simple hardware solution that will run 65536 tap length FIR filters? As far as I know there is not. Maybe one day. You could build one yourself of course, maybe PC based and running HQPlayer, but we are back in the realms of very hard work again.
1000 Pro - KEF Blade - iFi Zen Stream - Mutec REF10 - MC3+USB - Pro-Ject Signature 12
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#90
The length of the filter, number of taps generated by FFFD is selectable, choosing the 0.743/0.683 seconds option (on the view filter screen) will mean it generates 65536 taps for sample rates of 88200 and 96000. The generated files for sample rates 176400 and 192000 will be twice as many taps, 44100 and 48000 half as many.
Modern PCs can EASILY run filters of these lengths at these sample rates doing 64-bit double-precision math.
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