22-Dec-2021, 17:56
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.
@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
