Got the mic, got the computer now I need some help.

[AndrewM]

A question to some of the x-over guru's here, I've been thinking about getting ETF for awhile to help get the sound of my system tweaked to another level (I've been using CARA for awhile now). So along with that I'd like to start getting into measuring for speaker design. For the near term I'm going to go with one of Jon's M8 designs for my main system. But I have a few other project's I'd like to play with, I'd like to try and get my Focal kit squared away for a music/stereo TV system for the bedroom, and perhaps I'll start with a new set of computer speakers.

The biggest question I have is in regards to modeling software, LSPCad looks to be a great value for around $125 or so for the standard edition. But what about the "pro" version with it's x-over emulator? How well does that work? If it does work I could see quite a bit of savings with not having to keep hundreds of x-over parts around. I've also been playing around with SpeakerWorkshop, and I think I've finally gotten a handle on how the software operates, how does it compare to the commercial packages out there?

Any other resources to learn about x-over modeling (other than forums such as these)? As I mentioned I've been playing with SW and have actually made my first x-over design using measurements found on PE's site, however the modeled response looked worse than running both drivers full range, so I've got a long road ahead.

[JonMarsh]

ThomasW and I have a copy of both LSPCAD standard and LSPCAD Pro. I'm going to upgrade the pro version to the new version 6 shortly. But, right now, I do 90% of my stuff with LSPCAD standard. I also have an older copy of SoundEasy, but haven't updated that in a while. Some folks really like it.

LSPCAD comes with an MLS measuring tool which works pretty well with some sound cards- if you have an external mic and preamp, shouldn't be a problem. I use CLIO, which I've had for years. If I had more bucks to spend on this, I'd probably upgrade to Praxis.


I've got a biz trip later today, so don't have time to comment much.

The biggest key to making progress with any of these tools is understanding the crossover transfer function concepts, and applying the ones you want as target transfer functions for the optimizer- I use a combination of manual adjustment and optimization, as sometimes the optimizer is dumb as dirt- it doesn't pay attention to net impedance, except in the pro version. It can wind up hitting the target, but using a combination of components that results in a bad input impedance characteristic for the amplifier.

Tell you what, while I'm out at ThomasW's next week, I'll post some to this thread with some hints for how to measure and how to use the optimizer. I've covered some of this before, but it may not be in threads which directly address this topic.

Regards,

Jon

[ThomasW]

I've had the Pro version for years (I upgraded from standard when the Pro version was first offered), but have never used the emulator function. To me the concept of 'hearing' the differences using a PC soundcard just doesn't cut it.

Note that the Pro pricing is now quite high with the release of V6.0, and is going through the roof with even higher pricing Jan 1, 2005

Either version of LspCAD comes with free JustMLS software. So no need to buy ETF if you're going to get LspCAD.

There are a couple of freware MLS programs around, I'll see if I can find some links

No program is going to tell you how to design XO's or what XO will work best. All they do is graphically so you how your proposed idea circuit will model.

Jon and I still tweak all our XO designs based on real world testing of the actual speaker. And of course that means boxes and boxes of spare parts.

Although I've never used SpeakerWorkshop it looks like a very good tool, and the price is pretty good too ...... :wink:

[JonMarsh]

I've downloaded SpeakerWorkshop to look at it, but never seem to have enough time to give it a serious whirl- that said, some folks really like it.

I think there's a tendency that once you find a tool that works for you, and get's you the results you want, at least for me, I tend to stick with it, and concentrate on the projects instead. Some day I will have to update to Praxis, but that's a measuring tool, not a design synthesis program.

The SpeakerWorkshop Speaker Project Tutorial is good to go through to get a handle on the program, but it leaves out a lot of info regarding the evaluation process (what do you expect for free?).

Download Ingemar's Ugly Duckling project at the LSPCAD site.

LSPCAD

He's re-done/re-doing his web site again, so some stuff may not access right now... the Archive doesn't seem to be working at the moment, but I have that archived at home.

If you don't have Vance Dickason's book on speaker desgin, including crossovers, it's certainly recommended.

LSPCAD 6 is a bit of a learning curve if you're used to 5, but I think it has some cool features, so I'm going to bite the bullet.

~Jon