Feature Request for SoundEasy V27

Found a bug? Have a feature request? This is the place to talk about it.
dcibel
Posts: 39
Joined: Sun Dec 13, 2020 6:39 am

Re: Feature Request for SoundEasy V27

Post by dcibel »

I'd argue that the system sum and reverse null on the CAD module are somewhat irrelevant, as the driver location on the baffle is not considered here. So use the CAD frequency domain and optimizer to determine crossover slope only, then adjust again for final system response using the system module.

I've always found it to be a bit disjointed how SoundEasy has two different mechanisms for plotting and optimizing. If it were up to me, Frequency/Time domain under the crossover design menu would not exist, only the system plot would exist to avoid confusion, and both the crossover/filter optimizer as well as system optimizer would apply to the system frequency domain plots.

As an added feature request, implement "all pass" for system frequency targets so that you can draw a system target line with desired slope etc similar to the system optimizer target but on the main plot. The targets under system frequency plot only allow selection of filter slopes, some selections here simply cause SoundEasy to lock up / crash so that should be investigated as well.
meloV8
Posts: 34
Joined: Thu Dec 03, 2020 10:45 am
Location: Poland

Re: Feature Request for SoundEasy V27

Post by meloV8 »

I think it could be divided into a simplified version of crossover design and extended (with the possibility of full off axis response simulation).
Observing how people I know design crossovers, I can say that in 99% of cases they work with a very simplified scheme. Speaker measurements are not combined with near field response and do not include diffraction correction. The crossover is designed only to the point from which the microphone measurements were made. This is of course a very simplified path, but it may be sufficient for simple projects.
Similarly, in SE you can take shortcuts, not using HBT to check the speaker phase, but only design the crossover based on Far Field gated measurements, if the gate is long enough and the measurement system is accurate enough.

In case of SE and wanting to use the full potential of the program, the crossover design process must go through three separate steps, i.e. Frequency/Time Domain -> Front Panel Layout -> System Optimizer.
Additionally, it's a little strange for me that while working in Front Panel Layout you can't see the CAD editor window with the crossover diagram.

This spread of all these tools may be a bit unusual.

Lukasz
dcibel
Posts: 39
Joined: Sun Dec 13, 2020 6:39 am

Re: Feature Request for SoundEasy V27

Post by dcibel »

Oh I don't know about 99%...maybe 99% of new users making their first work.

For a simplified process, simply don't take any off-axis data and keep the mic at tweeter axis for simulation is all that needs to be done. In all honesty I don't think SoundEasy was designed for the uninitiated, I would recommend perhaps Xsim is a better option for "basic", of course an understanding of phase relations will still be necessary to measure and design with accuracy.

HBT is a bit overrated in my opinion, noise floor and extended frequency response that are corrected by HBT are generally well outside of the driver pass band where the crossover would be applied anyway. If you take decent measurements to begin with at a reasonable volume, it's unlikely that HBT is going to affect the final design result for better or worse.

You can, at least open the CAD editor and System frequency plot at the same time so you can see your schematic while you adjust values on the complete system.
meloV8
Posts: 34
Joined: Thu Dec 03, 2020 10:45 am
Location: Poland

Re: Feature Request for SoundEasy V27

Post by meloV8 »

Most just take shortcuts and do so because it is easier, or lack of time or skills.

Xsim is great for a start. It is Arta/REW/HOLMImpulse and can work, but there is also a similar Xover program that can already simulate Off Axis responses based on real Off Axis measurements. It is very easy to work in it and you can work really fast.

https://www.youtube.com/watch?v=Eac-pVx ... =emb_title

If you select the CAD Editor from the Crossover Design tab, by clicking on Frequency/Time Domain you can see both windows simultaneously on the screen. And this is as natural as it should be. But if we now go to System Tools/ Front Panel Layout, the CAD Editor disappears and you do not see the crossover diagram. You have to go again to the CAD Editor window from the Crossover Design tab. But if we go to System Polar Plots, CAD Editor is displayed. The same way in System Optimizer tab we can display CAD Editor window at the same time.
I do not understand why this is done. CAD Editor window should be available for each selected function from System Tools tab.

Maybe in V26 version it is different, in my V25 version it looks like I described above.
Bohdan
Posts: 36
Joined: Mon Dec 07, 2020 8:31 am

Re: Feature Request for SoundEasy V27

Post by Bohdan »

Hi Lukas,

Select (1) "CAD Schematic Editor" from Crossover Design menu then (2) "Frequency/Time Domain" from System Tools. The Schematic will stay opened. This is how V26 and V27 work.

I have uploaded Part II of the previous paper.
https://www.bodziosoftware.com.au/Using ... n%20II.pdf

Chad, please feel free to use any of the papers from my website.

Best Regards,
Bohdan
meloV8
Posts: 34
Joined: Thu Dec 03, 2020 10:45 am
Location: Poland

Re: Feature Request for SoundEasy V27

Post by meloV8 »

Hi Bohdan,

Thank you for your response.

There is probably a slight mistake on the website. In the description of these tutorials it is written: "24. Using Equalizer Function Highlights and Part II".
I think it should be "24. Using Optimizer Function Highlights and Part II" ?

Do you know the approximate release date of the V27.

Lukasz
Bohdan
Posts: 36
Joined: Mon Dec 07, 2020 8:31 am

Re: Feature Request for SoundEasy V27

Post by Bohdan »

Hi Dcibel,

Here is some perspective on HBT.

The algorithm was introduced in SE about 20-22years ago. At that time, the very first PC measurement systems started to appear (IMP). DIY users had great difficulties getting phase response measured, let alone minimum-phase response. So, HBT become essential tool in getting the transfer function of the loudspeaker calculated, because without transfer function, you cannot design the crossover. Back in the day, obtaining absolute minimum-phase accuracy was of secondary importance. What mattered, was the phase response, that could be used in loudspeaker design. The world-famous LEAP software used analogue measurement system and HBT to recover phase response.

Gradually over time, the measured phase has improved, and the focus of HBT turned into getting the phase as close to minimum-phase as possible. At that time, even experienced designers were placing the FFT window so close to the IR peak, that the phase was becoming almost a flat line above some frequency. This (obvious) mistake still prompted some designers to proclaim, that they designed “linear-phase” loudspeaker. HBT + Guiding Filter concept was born and served as quite good reference for determination if the phase response was even close to minimum-phase.

HBT is irreplaceable tool in loudspeaker equalization techniques. The whole concept of Ultimate Equalizer would fall apart if it was not for the HBT.

Now-days, as you mentioned, HBT has still many uses and HBT + Guiding Filter is still a good guide for placing the FFT window around the IR, but far more advanced technique was developed – the IHBT (Inverse HBT). Personally, I do not know of any other computer algorithm, which would allow you to extract minimum-phase with the same accuracy. You can read about it on my website.

Best Regards,
Bohdan
dcibel
Posts: 39
Joined: Sun Dec 13, 2020 6:39 am

Re: Feature Request for SoundEasy V27

Post by dcibel »

I did not mean to down play the importance HBT. My comment was specifically in reference to the use of SoundEasy for speaker design. Here we have a 2 channel measurement system capable of locking a consistent FFT window start, and because of that fact minimum phase is mostly unimportant for the design purpose, in fact if anyone were to follow John K's design guide, you would see that we are applying HBT only to correct phase at the very extents of the response where the noise floor and extents of the frequency response are impacting the phase, and then adding delay back in to this minimum phase response to match up with the measured FFT window. The resulting phase in the passband where the crossover has greatest impact is mostly unchanged. With this in mind, what is important for loudspeaker design, not just in SoundEasy but anywhere you have a true 2 channel measurement with reference channel timing reference, is that the FFT window start position is locked for all measurements, mic distance remains constant, and that the start of the window is always behind the impulse.

For this purpose, HBT and minimum phase for that matter, are not really contributing much to the outcome of the design. Whether the result of the measurement is minimum phase or not is irrelevant as long as you've captured accurate relative phase between drivers on the baffle.
Bohdan
Posts: 36
Joined: Mon Dec 07, 2020 8:31 am

Re: Feature Request for SoundEasy V27

Post by Bohdan »

Problem with relative measurements is - they are relative.
So, if you want to use a perfectly well measured driver in another system, then you have a problem.
Minimum-phase phase response and SPL should be treated the same as all T/S parameters.
They characterize the driver completely.
Bohdan
Posts: 36
Joined: Mon Dec 07, 2020 8:31 am

Re: Feature Request for SoundEasy V27

Post by Bohdan »

Chad,

Here is another paper I mentioned before. Feel free to use it.
https://www.bodziosoftware.com.au/Sound_Fields.pdf

Best Regards,
Bohdan
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