This new version includes a graphical tool to draw the cabinet and models the diffraction effects of the baffle. With this capability, PSD_Lite now provides a fairly comprehensive set of tools for designing multi-way passive speakers, and it is designed to be intuitive and easy to use.
This is still a Beta release, and I'm looking for some help with debugging and feedback on how to improve it. So please give it a try and comment in this thread or via PM. Thanks.
Here is a draft spec sheet for the program:
Http://www.audiodevelopers.com/Software/PSD_Lite_spec_sheet.htm
This is still a Beta release, and I'm looking for some help with debugging and feedback on how to improve it. So please give it a try and comment in this thread or via PM. Thanks.
Here is a draft spec sheet for the program:
Http://www.audiodevelopers.com/Software/PSD_Lite_spec_sheet.htm
Yes. There is a "Pro" version (PSD) that will be available for purchase, which will include driver, component and amplifier databases that make the design effort easier. It will also include some advanced functionality for optimizing the crossover and some additional analysis tools. Plus, it will create a Bill of Materials and support on-line parts ordering. There is another version (ASD) for designing active speakers, and for providing real-time control of DSP chips. All 3 programs share the same box modeler, baffle diffraction modeler, Amp/EQ modules and Driver Input modules.
PSD_Lite by itself provides all of the essential functionality for designing state of the art 2-way and 3-way loudspeakers. It is free and it is not crippled in any way--it simply lacks some of the cool features of the Pro or active versions.
What kind of optimization? Imo this is the only acceptable reason for another new free software.
There are a number of curve-fitting algorithms that can be used to identify a constrained number of poles and zeros needed to implement a specific target slope. I haven't gotten that far yet, but I don't see developing an optimizer as a major challenge.
PSD-Lite is a versatile framework that can be used to implement such features. PSD-Lite provides:
- A driver input module to read, edit and condition driver measurement data
- A good box model to predict low-frequency response, where measurement data isn't sufficient
- A baffle model to calculate diffraction and to calculate driver offsets
- An Amp/EQ model to predict the response of active components in the system
- An object model to specify the system components, attributes and their state
- Charting tools with auto-scaling and zoom
- Schematic drawing primitives for displaying the crossover
- A modular architecture with well-documented interfaces between modules
BTW, the original program was architected without a Crossover Module--passive crossover module was added later, and has never been the primary focus of this effort. PSD-Lite is a spinoff of the Active Speaker Designer (ASD), which is used to model DSP and can provide real-time control of various DSP chips and related circuitry via a USB interface (for example, this program can be used to design active speakers using a miniDSP board and can directly control the ADAU1701 chip on the miniDSP).
The top-level architecture is shown in the graphic.
For free software it isn't so. For non-free software, yes, but it must at least surpass any of the freewares.
Many of us don't really care if we have to use more than one or two software. But we really like to use the best software for its purpose. For MLTL there is the software, for vented box there is the software, for T/S measurement there is the software, for crossover design there is the software...
So for a new passive speaker designer, the software must be able to provide what the rest cannot, at least the ease of use. The optimization tool will be imo the most important tool. It is one of the tool that make a good crossover can be made accurately and quickly.
Simulator is simulator. It cannot make a good speaker/crossover. The designer can, but the software must provide the correct and accurate tools.
I can't make much sense of your "argument", but let me point out a couple of features that you would see if you actually tried the program. Maybe this response will serve as an antidote to your negativity and encourage some other people to evaluate the program.
First, each of the individual modules are as good or better than anything else available in "freeware". For example, the Woofer Box model uses the same accurate Benson model that Jeff Bagby used in his excellent WBCD Excel program. In fact, the first version of the Woofer Box model was simply a translation of his Excel program to .NET. But the user interface is vastly improved--you can quickly select values by rolling the mouse wheel, and in the full version of the program you can select from large databases of drivers and components. The Woofer Box module has an integrated graphical splicing tool that is very easy to use and that automatically populates the Crossover Module data. Similarly, the Baffle Diffraction tool is similar to the Edge program (same sort of ray-tracing routine), but it takes into account 1/R^2 loss to provide a more accurate model, and it models roundovers. And it goes well beyond Edge by providing a volume calculator that is integrated with the other tools. The Crossover Module provides the same filter types as the PCD program, but you can use the mousewheel to very quickly zero in on your target response. The use of background threads makes the user interface much quicker and more productive than PCD. And so on.... I think you will find that each module in PSD-Lite is either more accurate, easier to use or has more features than any other comparable "freeware" tool.
Second, an enormous amount of effort was put into making the program easy to use. Most of the code--probably over 80% of it--is for the user-interface rather than "calculations". Just about every textbox allows using a mouse wheel to select from lists of standard values. For example, the Crossover Module textboxes are tagged with a component code (resistor, inductor or capacitor), and the mouse wheel cycles through the standard values for that component that are available at PE or Madisound. And there is extensive use of drawing routines to help visualize the design--for example, the Crossover Module redraws the schematic whenever a new filter section is added. The end result is a user interface that is responsive, intuitive and more productive.
Third, this program integrates the various modules to provide unprecedented ease-of-use. For example, you can slope the front baffle in the side view and it will calculate the offsets to the measurement point and automatically add the appropriate delay to the driver measurements in the Crossover Module. Or you can check a box to add the calculated baffle step response to the Crossover Module. Or you can use the drawing tools to outline the box and the calculated volume gets sent to the Woofer Box module. Also, the Baffle module will subtract the calculated port volume from the box internal volume, and there are many other "cross-module" information flows. This integration makes loudspeaker design quicker and more convenient.
And finally, the program was designed from the beginning to be "open" and extensible. The extensible architecture allows me to add new modules in the future and to refine the existing ones with new features. You seem to think that the program has no value without a crossover circuit optimizer, but the architecture supports that capability and at some point it will get added and it won't require any significant redesign to support that capability. I heard the same complaint about needing a routine to extract minimum phase (Hilbert transform), and eventually added that capability in the Response Editor. This extensibility and open design is unique and isn't found in other freeware or commercial products. Take a look at the XML file created when the program is saved and you will see how comprehensive the object model is. I think the software architecture by itself is enough to get excited about, as there is finally an open framework in the DIY community for making more user-friendly, more accurate and better integrated loudspeaker design tools. You may not appreciate that open/extensible design feature, but others do. I intend to write an article on the Loudspeaker Object Model to help evangelize this design in the near future, as I hope to make this object model an open standard. I've also modeled the architecture using Enterprise Architect, so it will be possible share this architecture with others and allow integrating "third-party" tools. This program is actually very useful and convenient in its current state, but it is just the start of a much larger effort.
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No. My primary interest was always active systems, and PSD was a spin-off the Active Speaker Designer (ASD). ASD is still an active software venture, but it has evolved to where there is no longer much commonality between ASD and PSD. PSD is no longer maintained.
The biggest challenge with maintaining PSD was keeping the driver and component databases up to date. Not only are the databases out of date, the underlying database (Windows SQL-CE) has been deprecated. A new version of ASD-Lite introduces a better way of dealing with driver data--see this post.
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