designing custom passive crossovers...

[mph33]

im designing a 2-way waveguide monitor for personal use. i was wondering if there is software for designing passive crossovers. i dont want to go active. i know it would probably be easier but, i've always wanted to build a passive crossover. i'll be using a Seos15 wavegude/360 denovo compression driver and a FaitalPRO 15PR400 15" mid woofer. the enclosure will be ported at about 40" high.

http://www.parts-express.com/faitalpro-15pr400-15-neodymium-professional-woofer-8-ohm--294-1271

http://www.diysoundgroup.com/seos-15-preorder/seos15-preorder.html

http://www.diysoundgroup.com/compression-drivers/dna-360.html

[JonMarsh]

there are many packages for doing that; some paid and some shareware or free. Popular paid versions including LspCAD and SoundEasy.

On RJBAUDIO.COM there is a page for how to use the FRD Consortium tools (free) for designing speakers and crossovers. I'm a long time LspCAD user myself, though I used to use SoundEasy (from Australia) at one time.

[mph33]

there are many packages for doing that; some paid and some shareware or free. Popular paid versions including LspCAD and SoundEasy.

On RJBAUDIO.COM there is a page for how to use the FRD Consortium tools (free) for designing speakers and crossovers. I'm a long time LspCAD user myself, though I used to use SoundEasy (from Australia) at one time.

thank you for the quick reply. i will look in to LspCAD. do you think this design will be expensive and/or difficult? im pretty good at soldering, my only concern is the design.

[cjd]

Difficult? Component-wise, no. For a beginner? The learning curve is kinda steep. Lots of steps, lots of details, not all of which are always relevant.

If you don't have good measurements of any kind, you're in need of those. If you have good infinite baffle measurements, you may be able to execute the necessary steps to get reasonably close in-box data, though I'd hesitate to be guessing z-offset for those drivers. For best results, you need measurements in the final box. With the SEOS this may be your only option. Without measurements, none of these tools are going to be much help (though some come with the software to do measurements if you have the hardware.)

The easiest to get results tool for crossovers is definitely Jeff B's Excel worksheet (Passive Crossover Designer) - it's free.

That said, why not do one of the DIYSoundGroup's existing setups?

[mph33]

Difficult? Component-wise, no. For a beginner? The learning curve is kinda steep. Lots of steps, lots of details, not all of which are always relevant.

If you don't have good measurements of any kind, you're in need of those. If you have good infinite baffle measurements, you may be able to execute the necessary steps to get reasonably close in-box data, though I'd hesitate to be guessing z-offset for those drivers. For best results, you need measurements in the final box. With the SEOS this may be your only option. Without measurements, none of these tools are going to be much help (though some come with the software to do measurements if you have the hardware.)

The easiest to get results tool for crossovers is definitely Jeff B's Excel worksheet (Passive Crossover Designer) - it's free.

That said, why not do one of the DIYSoundGroup's existing setups?

i strongly considered DIYSOUNDGROUP's kits but... i didnt like the driver's used. their main focus is to target budget minded customers. im sure the components are good, but i dont like to compromise. i'd rather spend a little extra to get better results. ive also learned that Faitalpro drivers are fairly flat and easier to design crossovers overs for. now ive changed by mind on compression driver/horns. now i want to match with Faital. FAITAL PRO LTH142, and the FAITAL PRO HF140.

http://www.usspeaker.com/Faital%20Pro%20HF140-1.htm

http://www.usspeaker.com/Faital%20Pro%20LTH142-1.htm

[Saurav]

That Faital LTH142 is a Tractrix horn. Those have a reputation for sounding more 'honky' than oblate spheroid waveguides like the SEOS. I haven't personally tried either, so YMMV. If you want more waveguide options, check out 18 Sound. I've used their XT1086 in the past, and I thought it was pretty decent. I think there were some other people who'd done projcts with it, or had measured it. A search should turn up something.

[mph33]

That Faital LTH142 is a Tractrix horn. Those have a reputation for sounding more 'honky' than oblate spheroid waveguides like the SEOS. I haven't personally tried either, so YMMV. If you want more waveguide options, check out 18 Sound. I've used their XT1086 in the past, and I thought it was pretty decent. I think there were some other people who'd done projcts with it, or had measured it. A search should turn up something.

done a little more research, im going with the SEOS 15. it takes a 1" compression driver. for the money, this driver looks hard to beat(B&C DE250-8. ftr). i listen to mostly meta. ooking for good dynamics without over-revealing poor recording

[cjd]

done a little more research, im going with the SEOS 15. it takes a 1" compression driver. for the money, this driver looks hard to beat(B&C DE250-8. ftr). i listen to mostly meta. ooking for good dynamics without over-revealing poor recording

Still going to come down to a good crossover.

[CraigJ]

mph33,

Isn't the SEOS 15 and the B&C DE250 already half the kit at DIYSoundgroup? I'm sure Eric has the DE250, as well as other compression drivers (BMS or his brand) available. I don't understand your comment "their main focus is to target budget minded customers", as some extremely talented and well known designers have been involved with the group kits, including crossover design.

Finally, in spite of prior comments, Face has built a system using the SEOS12 + AE12 driver and can compare it to other hi end systems he has built or heard. IMHO, he might be worth a private message....

Cj

[mph33]

mph33,

Isn't the SEOS 15 and the B&C DE250 already half the kit at DIYSoundgroup? I'm sure Eric has the DE250, as well as other compression drivers (BMS or his brand) available. I don't understand your comment "their main focus is to target budget minded customers", as some extremely talented and well known designers have been involved with the group kits, including crossover design.

Finally, in spite of prior comments, Face has built a system using the SEOS12 + AE12 driver and can compare it to other hi end systems he has built or heard. IMHO, he might be worth a private message....

Cj

i checked out the diy site, i dont see B&C DE250 for sale. yes, Eric has mentioned several times to me that his kits were designed for budget minded diy'ers. he plans in the very near future to offer higher end components for his Alpha line. not trying to sound like a snob, i just hate to compromise. he's getting a lot more request for higher end designs.

[mph33]

Still going to come down to a good crossover.

sure will. this is my first passive crossover build. still lost lol. hell, i would pay for someone to build these crssovers

[cjd]

sure will. this is my first passive crossover build. still lost lol. hell, i would pay for someone to build these crssovers

Where are you located? That can go a long way to finding a crossover designer. The only time I don't do design work for free is if I have to build something - get the parts and box to me and it's a design I can do without having to actually build it myself, and that's a great way to feed my hobby. I'm not the only one out there, I just don't like speaking for others.

[mph33]

Where are you located? That can go a long way to finding a crossover designer. The only time I don't do design work for free is if I have to build something - get the parts and box to me and it's a design I can do without having to actually build it myself, and that's a great way to feed my hobby. I'm not the only one out there, I just don't like speaking for others.

im in atlanta. i would definitely buy the parts and ship... pay for someone to build the crossovers. i had a guy build me some crossovers for my old klipsch rf-7's. he did a killer job. made a huge difference in sound. to bad the speakers were stolen out of storage in orlando

[mph33]

well... i just learned that you need equipment to take measurements in order to design passive crossovers. i dont see how i could do this. i guess i have no other alternative but to go active

[Saurav]

You need equipment to take measurements to design active crossovers as well. Or at least, to design a proper custom crossover that's tailored to your drivers/enclosure/etc. You'll get some results with a stock off-the-shelf active crossover, but given the quality level of drivers you're looking at, IMO you wouldn't be utilizing their full potential.

[mph33]

You need equipment to take measurements to design active crossovers as well. Or at least, to design a proper custom crossover that's tailored to your drivers/enclosure/etc. You'll get some results with a stock off-the-shelf active crossover, but given the quality level of drivers you're looking at, IMO you wouldn't be utilizing their full potential.

what kind of measuring equipment do i need?

[Saurav]

A laptop or PC with a suitable soundcard, and a reasonably flat/calibrated microphone. The rest is software, and there's some very good free software, so you won't need to spend money on that for a long time. Search through threads on this forum, it's been discussed quite thoroughly. There are also several tutorials online.

The hard(er) part is knowing what to do with the measurements. Took me many months / years before I felt like I had a handle on enough of the aspects of crossover design that I could take a stab at it. I was happy with my results at that point, but I wouldn't put it up against the best of what you can find on a forum like this.

[mph33]

A laptop or PC with a suitable soundcard, and a reasonably flat/calibrated microphone. The rest is software, and there's some very good free software, so you won't need to spend money on that for a long time. Search through threads on this forum, it's been discussed quite thoroughly. There are also several tutorials online.

The hard(er) part is knowing what to do with the measurements. Took me many months / years before I felt like I had a handle on enough of the aspects of crossover design that I could take a stab at it. I was happy with my results at that point, but I wouldn't put it up against the best of what you can find on a forum like this.

build my crossovers... i'll pay you lol

[Saurav]

You'd be much better off with someone like cjd, who actually knows what he's doing Or better yet, ask here, DIY Audio, Tech Talk, etc., and see if you can find someone local.

[mph33]

You'd be much better off with someone like cjd, who actually knows what he's doing Or better yet, ask here, DIY Audio, Tech Talk, etc., and see if you can find someone local.

i asked cjd.. i guess he's to busy lol

[Saurav]

Yeah, I'm sorry, I don't have the time either. 2 young kids have a way of doing that to you Good luck on your project.

[cjd]

i asked cjd.. i guess he's to busy lol

Well, I just sold my "hobby" car and am doing some related cleanup, trying to get the new year off to a good start. Yeah, we're kinda a few weeks in but...

Anyhow, I'm open to working with you on this, and I replied. Have to figure out logistics.

I'm not sure which drivers you settled on after skimming through the thread again. Still the Seos15 wavegude/B&C DE250 and a FaitalPRO 15PR400 15" mid woofer? 4ohm or 8ohm on the FaitalPRO?

The FaitalPRO looks like it's best suited to a 1kHz crossover max, and the size puts C2C rule within that same range. The B&C is recommended for a higher point, though I don't know what the SEOS does to change that (certainly it appears usable for a ~1kHz crossover with the SEOS15)

The box looks pretty big. I'm getting 21.5w, 40"h, 15.5" deep with 2 3" ports 5.5" long. Not something to ship assembled.

[mph33]

Well, I just sold my "hobby" car and am doing some related cleanup, trying to get the new year off to a good start. Yeah, we're kinda a few weeks in but...

Anyhow, I'm open to working with you on this, and I replied. Have to figure out logistics.

I'm not sure which drivers you settled on after skimming through the thread again. Still the Seos15 wavegude/B&C DE250 and a FaitalPRO 15PR400 15" mid woofer? 4ohm or 8ohm on the FaitalPRO?

The FaitalPRO looks like it's best suited to a 1kHz crossover max, and the size puts C2C rule within that same range. The B&C is recommended for a higher point, though I don't know what the SEOS does to change that (certainly it appears usable for a ~1kHz crossover with the SEOS15)

The box looks pretty big. I'm getting 21.5w, 40"h, 15.5" deep with 2 3" ports 5.5" long. Not something to ship assembled.

i just built a table saw station and waiting for my router table to arrive. im pretty stoked about building cabs and random stuff around the house. also waiting on a b&c 21" sub once stock is avaible through partsexpress. gonna build an othorn to match with some high efficient monitors. huh... do you think i should possibly go with a different compression driver that crosses over higher? i look forward to working with you

[Dave Bullet]

Here's a cheap and tutorial way to setup a basic measurement rig.

google claudio negro speaker workshop manual and cable jig
speakerworkshop is free and does basic measurements and crossover simulations

I run a windows 98 PC,event 1 pre-amp (phantom power) to a XLR mic (behringer ecm8000)

The most expensive part is the microphone (don't know how much they are) and if your soundcard can't provide phantom power, using a microphone preamp (ebay)

I reckon for $100 you could get underway.

The active route will still require a measurement setup anyway (plus all the active components).

[cjd]

I can NOT recommend using SpeakerWorkshop for measurements. It's a nightmare compared to ARTA (which is pay-to-save but works great), and I'd guess compared to HOLM (which I haven't used.) All this assumes you work on a Windows machine, otherwise you'd likely be looking for Fuzzmeasure on a Mac, and SOL on Linux. With ARTA the raw PIR files could be shared so anyone working on a crossover could handle gating, slice and dice, etc. 7 datapoints are likely valuable, with each woofer+tweeter pair done without moving the box or the mic at all. Woofer+tweeter wired together (both playing); on-axis woofer, on-axis tweeter; 15 degree off-axis tweeter, 15 off woofer; 30 off tweeter, 30 of woofer.

I used to spend hours trying to get clean data out of SpeakerWorkshop. Worth every penny I paid for ARTA to stop using it.

If this is likely to turn into a repeat event, investing in measurement gear is a solid choice. Longer learning curve of course.

C

[mph33]

well... here's a response from Faital. took them forever lol.

FaitalPRO Info info@faitalpro.com
2:31 AM (16 hours ago)

to me, Keith
Dear Satan,

Thank you for contacting us about your project,

After reviewing your requests with our R&D dept., we can suggest the following:

Ideally you want to create an enclosure with a NET Volume (i.e. the free volume inside the enclosure once you take out the volume occupied by the drivers, the electronic parts and the tuning/reflex ducts) of 80 Liters (2.83 cu.ft.), with 2x reflex ducts with an internal diameter of 3.5” and a length of 8.8” and a tuning frequency of 40 Hz.

As far as the models chosen, we think they are a good choice but we have a hard time suggesting a specific crossover without the physical box available for measurements and we suggest you refine the crossover once you have built the box and you are able to measure it…

[cjd]

I tune a little lower, but that's just how I find things work best. If you want more thump, their tuning recommendation sounds about right.

[mph33]

I tune a little lower, but that's just how I find things work best. If you want more thump, their tuning recommendation sounds about right.

cant wait to start this build. so i can just send you a flat pack for one cab and the speakers and you can design the crossover?

[cjd]

That'll absolutely work.

Might be worth checking with Erich if he's interested in the end combo as an offering - one of his existing flat packs may suit quite well.

[mph33]

That'll absolutely work.

Might be worth checking with Erich if he's interested in the end combo as an offering - one of his existing flat packs may suit quite well.

end combo?

[mph33]

i was just thinking... those guys over at avs has nagged the hell out of Erich to do higher cost premium kit. not bashing the kits he has available, but they tend to be more suited for ht vs hifi and or both. im sure they sound fine for music but i think the drivers i've selected for this particular monitor would excel at both. im not an acoustics engineer but ive looked over the specs for the faital 15" and it looks excellent. will play high, efficient, and plays lower than a lot of pa drivers. i think if we nail this... we just might have future diy kit. that would be cool. never thought of any thing like this