• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required. There are many reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

Suggestions for three-way crossover filters?

Hello OP @DanieIT

Just for your reference, my multichannel multi-driver (multi-way) multi-amplifier fully active L&R stereo audio project with OKTO DAC8PRO and software DSP (XO/EQ) "EKIO" (very nice and simple GUI) would be of your interest.

You would please find details of my latest system setup here.

I prepared hyperlink index here and here for my project thread.

"EKIO" on Windows PC enables very much flexible (even on-the-fly) GUI XO/EQ settings and also delay (time alignment) tuning in 0.1 msec precision which really "matters" for the amazing total sound quality including the disappearance of SPs, as shared here.

"EKIO" can work as system-wide one-stop XO/EQ center (unlimited numbers of input/output channels) receiving audio signals from JRiver MC, Roon, Adobe Audition, AudaCity, internet browsers, etc. through ASIO4ALL (free) and VB Audio Virtual Cable (free).

If you would be seriously interested, I will be more than happy sharing with you the test tone signals I prepared for precision measurements/adjustments of time alignments as well as for measurements of SP transient characteristics.

I use OKTO DAC8PRO in my multichannel project, but now you can do exactly the same with TOPPING DM7, I believe.
I think this is the Gold Standard for a fully active DIY. I appreciate how well you have documented your journey. Next iteration of my active 3-way system I am going to take a similar path as @dualazmak. Thank you.
 
Try Audiolense, its fully automated fairly easy to use and seem like the more advanced options out there.
 
Excellent, thanks for all the answers.:D

Now I got more energy and desire to start DIY. I had intended to start earlier this year but was delayed due to, among other things, a lumbago from hell at the beginning of May. I had to work that out. After that, I prioritized painting and fixing general maintenance on the house. But it doesn't matter, I'm really in no rush. Plus, now I have something to look forward to, something fun.:)

I feel like a child about to open Christmas presents. :p
Summary, so far on suggestions:
(I may have missed a suggestion but I will definitely study this thread more closely so nothing escapes)

*Camilladsp with raspberry pi
*Topping DM7
*miniDSP in various variants
*DCX2496
*Jriver's DSP engine
*OCTOBER DAC8PRO
*DSP EKIO
*OpenDRC kit
*Deer Creek Audio
*Audiolense

Very interesting. I will study what is proposed closer, in more detail. I mentioned the active crossover LD X-223 earlier. I'll post some pictures of it. It was such a good offer so I couldn't resist buying it. Without having really thought the whole thing through, mostly I had, or maybe have thoughts about someday using it together with sub-speakers. Crossover then around 80 Hz. But I might be able to use it, mostly to test as a crossover between bass-midrange in my three-way DIY speakers. Don't really know how accurate it will be between the channels when you screw manually and set the crossover points, see picture.Have also read that some say that such an active crossover can be a bit noisy, but that's just for me to try.:)

LD X -223 reminds me a lot of this:

 

Attachments

  • IMG_20220811_063648.jpg
    IMG_20220811_063648.jpg
    184 KB · Views: 61
  • IMG_20220811_063711.jpg
    IMG_20220811_063711.jpg
    176.3 KB · Views: 52
  • IMG_20220811_063800.jpg
    IMG_20220811_063800.jpg
    170.9 KB · Views: 62
  • IMG_20220811_063800.jpg
    IMG_20220811_063800.jpg
    170.9 KB · Views: 76
Last edited:
If i was to do something like that, i would totally go for raspberry pi with camilladsp to the new topping dm7. Total cost ca 700 eur. and 2 unused channels if one day you want to add subs.
But:
I am not sure anyone has confirmed yet the DM7 works well in such a system.
You will need all your amps balanced.

No need to know any programming. Have a look here:




That's the beauty of the topping DM7: it is a multichannel dac AND a preamp. You just need to plug your power amps to it, adjust the different gains in camilladsp and the DM7 gives you master volume control with volume knob and remote control.... a dream for your project IMHO.

Get a second hand DCX2496. Or, you already have a MiniDSP, get another one.

CamilaDSP has a web interface nowadays, so is much more accessible.

Of course I need to shill my own solution :D, if you can copy / paste and follow instructions you can install CamillaDSP on a RPi4. There is nothing resembling programming because I have done all of the hard work for you. I have not encountered anyone that has been unable to successfully install it. A DAC with remote volume control like the Okto dac8 pro or Topping DM7 eliminates tons of complexity as well, no need to worry about displays or IR receivers.

Once you have it installed usability is just as good as miniDSP, if not better as you can configure it from any phone / computer connected to the same network.

I was a miniDSP user for many years but these days it is so hard to beat CamillaDSP and a multichannel DAC if you need more than 4 output channels. Unfortunately all of the minidSP 4+ channel multichannel offerings with analog outputs are bit noisy (4x10HD, OpenDRC-DA8, DDRC-88A) although the previously mentioned hybrid solution of a miniDSP Flex + passive crossover on the mid / tweeter is a decent option.

Michael
Okay, maybe I judged CamilaDSP a little too quickly when I skimmed through the beginning of that thread. It was probably my preconceived notion that caused me to read something like this:
This looks like hardcore DIY computer skills needed....BUT if you look at it, you should be beware of preconceived notions. Or I should be beware of it.:oops: It doesn't look at all as difficult as I thought, now that I have checked the thread about CamilaDSP that is referred to.:)

CamilaDSP has now definitely become an interesting alternative for me. Thank you for opening my eyes!:D
 
Last edited:
  • Like
Reactions: MCH
If it was me I'd just but a (analog) crossover. Plug it in, twist a few knobs, and you're done! Or buy some plate amplifiers or "amplifier modules" and build a full-active speaker. (But that would probably mean building a DIY crossover.)

...I'd recommend a capacitor on the tweeter, and maybe the midrange too, to block low frequencies when something "goes wrong" or in case something is accidently wired-wrong. (That can be chosen to "cross over" at a lower frequency so it doesn't interfere with the actual crossover.)


If you are going to bi-amp or tri-amp, active has a few advantages.


P.S.
A lot of pro amps have DSP "crossovers" (filters) built-in and that simplifies things a lot. But you'd have to buy 3 new amps, and most of these amps have (noisy) cooling fans.

Minidsp is fine. You can do with (2) minidsp 2x4s with the right plug-in...

Before you spend anything, would model it all in VituixCAD. It has the filters for the minidsp and other active crossovers. If you do the protective cap on the tweeters, hiss will be less likely to be an issue. IMO, once you start doing the cap, might do the whole tweeter passively. Ofc, depends a lot on the tweeter.
Yep, capacitor on the tweeter. Definitely in the beginning so I don't risk burning the tweeters when I test different settings. That regardless of which solution I proceed with.:)
 
Excellent, thanks for all the answers.:D

Now I got more energy and desire to start DIY. I had intended to start earlier this year but was delayed due to, among other things, a lumbago from hell at the beginning of May. I had to work that out. After that, I prioritized painting and fixing general maintenance on the house. But it doesn't matter, I'm really in no rush. Plus, now I have something to look forward to, something fun.:)

I feel like a child about to open Christmas presents. :p
Summary, so far on suggestions:
(I may have missed a suggestion but I will definitely study this thread more closely so nothing escapes)

*Camilladsp with raspberry pi
*Topping DM7
*miniDSP in various variants
*DCX2496
*Jriver's DSP engine
*OCTOBER DAC8PRO
*DSP EKIO
*OpenDRC kit
*Deer Creek Audio
*Audiolense

Very interesting. I will study what is proposed closer, in more detail. I mentioned the active crossover LD X-223 earlier. I'll post some pictures of it. It was such a good offer so I couldn't resist buying it. Without having really thought the whole thing through, mostly I had, or maybe have thoughts about someday using it together with sub-speakers. Crossover then around 80 Hz. But I might be able to use it, mostly to test as a crossover between bass-midrange in my three-way DIY speakers. Don't really know how accurate it will be between the channels when you screw manually and set the crossover points, see picture.Have also read that some say that such an active crossover can be a bit noisy, but that's just for me to try.:)

LD X -223 reminds me a lot of this:

Yes, the DBX does look similar.
Yes, two of these crossovers plus six amps could be used to implement a 3-way active (these are stereo for 2-way, mono for 3-way...)
However, you will only be able to set crossover points and levels. You won't have flexibility on the slopes (I haven't read the manual but it doesn't look like that crossover has adjustable slopes).
Something like a MiniDSP will allow all sorts of slopes, in this case LR 24dB/octave but there are a bunch of alignments.
1660196173039.png

What the analog crossover really cannot do is implement detailed driver corrections (OK, they can but it is a bit less straightforward, see for example https://www.linkwitzlab.com/filters.htm). Examples are a shelf to compensate for the baffle transition from half to free space, or a notch filter to deal with a cone breakup mode.
1660196539691.png

These are MiniDSP screenshots, but they are not unique features, and these could be implemented exactly using @dualazmak system. In fact, I could fly to Japan with my speakers (no electronics) and insert them into his system, configure his crossover with my settings, and be up and listening to his music collection in an afternoon! It would take some fiddling with the gain since his amps are not the same as mine, but that is not a big deal. And his room is undoubtedly different, and that is a big deal. So that would need to be dealt with, but then there is REW, etc. Pretty quickly, either he or his family would have to kick me out!:)

And then you can buy one of the mobile DSP and do your car too.;)
 
Simulate the tweeter to mid with software + DSP and make a passive filter, IMO. Save the DSP/active for the bass filter. Passive bass filters tend to require large and more expensive components.

This also gives protection for the tweeter and may lower distortion and compression a tiny bit if you drive the tweeter with a higher resistance.
 
I would start with a cost effective analog,there's lot's out there if you can solder some cables.As long there's a lot of test to be done analog maybe will not be the most easy but it will be safe and as long as you already have a preamp you will not have any limitation to sources or many conversions.
After you settle you can go for an Okto and be done with it.
 
"Protection of our treasure midrange drivers, tweeters and super-tweeters" is always one of the critical features in multichannel multi-amplifier active audio system!

I highly recommend you to use "proper" protection capacitors for your treasure mid-range drivers, tweeters and super-tweeters.
I use these, 68 microF Caps for Be-midrange squawkers, 10 microF Caps for Be-Tweeters and metal horn super-tweeters;
WS000636 (1).JPG


WS000817.JPG


And, I carefully compared the Fq responses in SP level signal "before and after" the protection capacitors as shared here and here; I confirmed that these protection capacitors have little (or no) audible Fq effect.

Also please note;
- Elimination of magnetic susceptible metals in SP signal handling: #250, #013(remote thread)
- VCT (vinyl Cabtyre) multicore flexible cables (AWG10, AWG12) for amplifiers into speaker drivers: #028, #137

As for "protection of SP drivers", shutdown sequences and ignition (startup) sequences for the total system should be carefully considered and implemented.

Even though I know many people use 5 - 12 VDC trigger function(s) of DAC(s) and amplifier(s) for simultaneous ignitions all together, IMHO, it should be avoided from safety point of view.

And, at least your "master volume" should be off or minimal (minus infinity dB position) at the system ignition. I myself believe all of the digital and analog SP gains should be also off or minimal at the ignition to protect our precious SP drivers from unexpected clipping and/or possible ignition pops.

Just for reference, at least I myself am always much careful in "shutdown sequences" and "ignition (startup) sequences" in my multichannel multi-amplifier setup, as I shared here.

And so on, and so on...

We have several "common" critical issues/features for building our multichannel multi-amplifier active audio system. Whatever hardware and/or software you would select and implement, therefore, you would please carefully look at, prior to your first step, the hyperlink index (here or here) for my project thread which well covers almost all of the critical issues, I assume.
 
Last edited:
The DBX PA2 can do that, and has a relative good working auto function with the optional measurement mic. It's probally the best option if you don't want to make it to techincal complicated. But it's no free lunch neighter, there is still some knowledge and tinkering needed.

If you want full digital in, you need the much more expensive Venue 360, but it can do the same.
 
Hello again OP @DanieIT,

In case if you already have your 3-way stereo SP (SP drivers), multiple amplifiers (preferably capable of XLR balanced input), and Windows 10 (or 11) Pro PC, all you need to simulate my latest system setup is to purchase software DSP LUPISOFT "EKIO" (US$ 149) and 8-Ch DAC TOPPING DM7 (US$ 599).

Of course you also need one USB 2.0 cable (I assume you already have!), several TRS(balanced)-XLR(male balanced) cables, and multicore SP cable(s) as well as protection capacitors, these are rather reasonable/cheaper ones.

Consequently, you can very easily and cost-effectively establish and test/try "highly flexible GUI based" multichannel multi-driver multi-amplifier fully active audio system; the flexible XO/EQ and time alignment capabilities as well as the total sound quality are the same or even better than the extraordinary expensive TRINNOV Altitude 32.
 
Last edited:
Just out: Flex 8

All-in-one.

Thanks for the link, I did not know.
This looks well suited to the OP's plans.
It says "Flexible I/O versions for unbalanced/balanced/digital connectivity Array", that sounds interesting... I don't see those versions yet...
 
"Protection of our treasure midrange drivers, tweeters and super-tweeters" is always one of the critical features in multichannel multi-amplifier active audio system!

I highly recommend you to use "proper" protection capacitors for your treasure mid-range drivers, tweeters and super-tweeters.
I use these, 68 microF Caps for Be-midrange squawkers, 10 microF Caps for Be-Tweeters and metal horn super-tweeters;
View attachment 223591

View attachment 223592

And, I carefully compared the Fq responses in SP level signal "before and after" the protection capacitors as shared here and here; I confirmed that these protection capacitors have little (or no) audible Fq effect.


Also please note;
- Elimination of magnetic susceptible metals in SP signal handling: #250, #013(remote thread)
- VCT (vinyl Cabtyre) multicore flexible cables (AWG10, AWG12) for amplifiers into speaker drivers: #028, #137

As for "protection of SP drivers", shutdown sequences and ignition (startup) sequences for the total system should be carefully considered and implemented.

Even though I know many people use 5 - 12 VDC trigger function(s) of DAC(s) and amplifier(s) for simultaneous ignitions all together, IMHO, it should be avoided from safety point of view.

And, at least your "master volume" should be off or minimal (minus infinity dB position) at the system ignition. I myself believe all of the digital and analog SP gains should be also off or minimal at the ignition to protect our precious SP drivers from unexpected clipping and/or possible ignition pops.

Just for reference, at least I myself am always much careful in "shutdown sequences" and "ignition (startup) sequences" in my multichannel multi-amplifier setup, as I shared here.

And so on, and so on...

We have several "common" critical issues/features for building our multichannel multi-amplifier active audio system. Whatever hardware and/or software you would select and implement, therefore, you would please carefully look at, prior to your first step, the hyperlink index (here or here) for my project thread which well covers almost all of the critical issues, I assume.
Interesting, especially when you say and demonstrate: And, I carefully compared the Fq responses in SP level signal "before and after" the protection capacitors as shared here and here; I confirmed that these protection capacitors have little (or no) audible Fq effect.

Hello again OP @DanieIT,

In case if you already have your 3-way stereo SP (SP drivers), multiple amplifiers (preferably capable of XLR balanced input), and Windows 10 (or 11) Pro PC, all you need to simulate my latest system setup is to purchase software DSP LUPISOFT "EKIO" (US$ 149) and 8-Ch DAC TOPPING DM7 (US$ 599).

Of course you also need one USB 2.0 cable (I assume you already have!), several TRS(balanced)-XLR(male balanced) cables, and multicore SP cable(s) as well as protection capacitors, these are rather reasonable/cheaper ones.

Consequently, you can very easily and cost-effectively establish and test/try "highly flexible GUI based" multichannel multi-driver multi-amplifier fully active audio system; the flexible XO/EQ and time alignment capabilities as well as the total sound quality are the same or even better than the extraordinary expensive TRINNOV Altitude 32.
I have a mix of balanced and unbalanced HiFi stuff but it should be the same across the range. I can sell if necessary. Still bought the stuff used and can buy something else, preferably used. I think you get the most for your money then. :DUnless the stuff breaks shortly after purchase, of course.:oops:

But I am not selling my Sela power amp. That is because it is part of Swedish PA history. I assume it is balanced with it, see picture below. But there is no documentation about that amp.

Here is some more information, or rather thoughts, about the Sela power amp. Plus a lot of pictures when I take apart the card.


IMG_20220811_203100.jpg


Sela for midrange. For bass, I'm thinking of using my subwoofer amp, t amp E-800. :)
(it now has silent fans installed). It can probably work well if it drives bass up to around 300 Hz.
 
Last edited:
Simulate the tweeter to mid with software + DSP and make a passive filter, IMO. Save the DSP/active for the bass filter. Passive bass filters tend to require large and more expensive components.

This also gives protection for the tweeter and may lower distortion and compression a tiny bit if you drive the tweeter with a higher resistance.
Speaking of capacitor. I plugged one in when I test drove my 18 Sound XD125 compression drivers, see attached picture.

Incidentally,I'm going to test this:
XD125..... VS...
https://hificompass.com/en/speakers/measurements/sbacoustics/sb-acoustics-sb26adc-c000-4

I guess I'll see which one I like best, make the most sense with other elements/crossovers/EQ (if necessary). They have different character, FR and directivity, propagation of the sound. :)
See attached pictures.
 

Attachments

  • sb26adc-c000-4_offaxis (1).png
    sb26adc-c000-4_offaxis (1).png
    102.5 KB · Views: 63
  • 20220811_183614953.jpeg
    20220811_183614953.jpeg
    123.3 KB · Views: 61
  • 20220811_183745690.jpeg
    20220811_183745690.jpeg
    80.8 KB · Views: 56
  • 20220811_183818939.jpeg
    20220811_183818939.jpeg
    95.8 KB · Views: 63
  • IMG_20220811_204230.jpg
    IMG_20220811_204230.jpg
    157.3 KB · Views: 63
Last edited:
Just out: Flex 8

All-in-one.

It certainly seems interesting.

There are exciting suggestions in this thread. I really appreciate all the tips, suggestions and advice given! This will be a fun autumn. :)
 
More than one way to skin a cat, here is another perspective.

If I were starting all over I might go for a mini-dsp but currently I am using a 4 way DIY analog crossover https://sound-au.com/project09.htm for a tri-amp system with sub and REW / Rephase to linearize the crossover phase and do room / speaker/ phase EQ and it works and measures well. When I think about how much it would cost to switch to digital and how much work it would be and how little I could possibly gain I just leave things be. There are a few advantages to analog crossovers the 2 biggest being you only need a 2 channel DAC and I get to keep my "real analog tone controls". I think it is probably cheaper, faster, and easier as well.... just not as flexible.

Another perspective on "protection caps": To me having a clean signal path from amp to speaker is one of the main advantages of an active system. If I was using super expensive drivers maybe I would use protection caps but a cap will have some effect on phase and FR and fancy metal film caps of the size you need are expensive (more than my drivers) so I leave them out. If I was going to use them I would use bi-polar electrolytics . I have had a DIY tri-amp system for many years and despite a few small accidents never blew a driver but it could happen. I think sizing the amps appropriately is probably the best way to go.... there is no need for a 150 watt amp to be driving a tweeter.
 
Speaking of capacitor. I plugged one in when I test drove my 18 Sound XD125 compression drivers, see attached picture.

Incidentally, some I'm going to test now this autumn. XD125 vs
https://hificompass.com/en/speakers/measurements/sbacoustics/sb-acoustics-sb26adc-c000-4

I guess I'll see which one I like best, make the most sense with other elements/crossovers/EQ (if necessary). They have different character, FR and directivity, propagation of the sound. :)
See attached pictures.
There is nothing wrong with going active all the way. I used to do it but got tired of all equipment and made a passive filter for my top speakers and left active for the bass. Two power amps instead of three etc, Audyssey instead of parametric EQ etc. I think with one miniDSP filter you can arrange the bass to mid xover, baffle step and EQ for the whole range? Even if you have a passive for tweeter/mid.
 
Just out: Flex 8

All-in-one.

Yes, was going to post this. This immediately becomes the easiest and most flexible unit out there for active multi-way speaker projects.
 
Back
Top Bottom