Mini DSP Digital Crossover Setup for my Open Baffle Speakers

[@IBuildIt]

Watch the full build video showing how I made these speakers: kzbin.info/www/bejne/oWWuf3SKZdVqhZY The speakers are fully active and use a MiniDSP 4x10 for the crossovers. In this video I quickly go over setting up the crossovers in the DSP and measuring the results. While not exhaustive, this will give you an idea of what's involved in tuning this type of speaker system. For this set up the measurement mic was 1 meter away from the right speaker on axis with the tweeter. The off-axis measurements were done at the same distance - 1 meter. The system consists of the computer I use to play music (and movies, shows, etc.) that outputs the digital signal to the MiniDSP, so all of the crossover settings (and eq) happen in the digital domain before being converted to analog. The analog output for each driver is then sent to the 12 channels of amplification I have that powers the speakers and subs - 8 for the speakers an 4 for the subs. Like I said in the video, you can look at these as 5-way speakers, with a sub, woofer, mid-woofer, midrange and tweeter on each side. This is a two channel set up, not a home theater.

[@oconnaugh]

John, I am thinking of running signal into mini dsp, filtering/tuning each channel to a specific driver, and then a dedicated small amp for each speaker. Maybe some LM3886 amps for the mids and tweeter, and a more robust amp for each bass driver. So dividing sifnal with dsp, and each driver has it's own amp. Using the UMIK to balance to the room, one could have quite a system for a modest dollar cost. Btw, I talked to a couple pro event sound engineers and they both agreed this is how arena audio systems are designed.

[@audfrknaveen2256]

This is a pains taking process for many people...but you made it look so simple 😀😀😀😀👍👍👍 great video !!!!

[@erics.4113]

This is great content. I love what you're building over there. Can't wait to get my hands on a miniDSP and start with REW for my 2.2 setups

[@chikmanso3079]

This is the modern, proper way of doing audio👍

[@willbrink]

My understanding is an active X over is the way to go, and miniDSP best choice for that. I'd like to build a two way with an active X over and see what that sounds like. I wish I knew more about the topic!

[@leslubiesdetienne]

I should have bought in to minidsp when they came out and prices were much much lower.. it does look very flexible and worth the price. Thanks for the video. Very interesting to see the process.

[@attainableaudio4533]

"Make sure that nothing evil is happening" 5:40 love it!

[@4sale125]

Do you have a video showing all the audio/video equipment you are using? Your woodworking skill has left me speechless. Awesome!

[@Take-the-Ticket]

Yay I was hoping this would be a video coming soon. I only have experience with designing with caps and stuff, haven't gotten into DSP yet. Thanks :)

[@alexz1232]

How do you like the relatively flat in-room response? In normal untreated room that usually sounds harsh and bright, but your room has a lot more treatment than most.

[@sudd3660]

fun too look at how other people does dsp. looks pretty similar to my diy speaker build, a bit different since i used another minidsp product(shd studio) and also a hypex fusionamp. dsp really is powerful tool

[@anandshah71]

How do you find the Hypex fusion dsp compared to miniDSP features and sound

[@sudd3660]

@@anandshah71 i can not compare sound directly since i used them differently, the hypex fusion amp i used as a crossover, dac and amplification, for main speakers. the minidsp shd studio i use as room correction and subwoofer dsp and integration to main speakers. main speakers with hypex plate amp was connected to minidsp by digital xlr. i can comment on the hiss noise the hypex produced, it was not something i could live with nearfield listening. but the software itself i can say more about, minidsp is easier to use, but hypex is more advanced. and having hypex as plate amp causes issues, and are not user friendly to set up and tweak. My minidsp is digital only seperate box, where i can reach it easily and do not require a compartment in a speaker or something to sit in.

[@donaldmumaw]

Very interesting but also over my head 👍

[@IBuildIt]

That's okay, it's mostly over mine too :)

[@anandshah71]

Will Dirac solve the complicated process.

[@asdfasdfasdfasdeff]

@@anandshah71 Dirac will if anything complicate it even further. Dirac is icing on the cake, you do it after all of this for room correction

[@stevenvictordelrosario3454]

Woah, great video mate!

[@LaseringS]

Awesome! Can you show the final result and compare to the untweaked version?

[@zeekbruno4869]

John when are you going to look at Timing of the drivers ? Phase

[@ShainAndrews]

Sure is a heck of a lot easier to dial these systems in than it used to be.

[@robertgates3258]

Wow..youre a wiz at that software. Like watching Bob Ross do a painting.

[@michaelpiotrowicz6100]

Why do you choose not to gate the test signal. Is there some reason why you are trying to setup the crossovers to be right with room reflections included in the output? Do you want to have the crossovers different for each speaker dependent on the room and the microphone location? I would never do it on purpose but I build analogue crossovers and do not have the flexibility, is there some advantage?

[@IBuildIt]

These speakers are for this room, and not some other room that's a different size and shape. So Including the reflections / room modes in the measurements actually makes them more accurate.

[@bbfoto7248]

@@IBuildIt Nope. You're correcting/adjusting the X/O for things that the microphone hears *in your room* but your TWO Ears combined with your BRAIN are filtering out and disregard. In addition, you're not doing multiple measurements within the "listening window" and using spatial averaging, or a moving mic method for your room correction measurements. So the in-room "response" you are measuring (single point in space) is not a true representation of what you are hearing. The proper way to design your loudspeakers is to adjust your X/Os for the speaker's smooth & even response themselves (anechoic response, at least where you can down to the Schroeder Frequency using gating). Any IN-ROOM response and corrections should be dealt with AFTER the anechoic response (and Directivity) of the speakers are optimized. Use spatial averages of many measurements within your listening position's "head window", or a moving mic method, for your room correction adjustments. I also think that you are underestimating the importance of achieving Smooth & Even Directivity in your loudspeaker system "because my room is acoustically treated so well that it doesn't matter". Rubbish. Unless you are listening in the extreme nearfield with NO nearby boundaries (including floor & ceiling), or with headphones, Directivity still matters quite a bit. As it is, if you decide to change the position of your loudspeakers even just inches in the future, EVERYTHING you have done with this "X/O tuning" technique will basically be a wash. :-/ I'm assuming you have Floyd Toole's "Sound Reproduction" and Vance Dickason's "Loudspeaker Design Cookbook" and revisit them often? You can also Download the FREE *JL Audio TüN 4.x* measurement software from their website which now has libraries from *Smaart v8* integrated for real-time phase response visualization. They sell a proprietary *TüN MAX* audio interface with a high quality 5-mic measurement array that works with the TüN software, but you can use any USB measurement microphone such as your UMIK-1 with the software (albeit with some obvious limitations). The TüN software and MAX measurement system are designed for their *VXi-series* of car audio DSP/amplifiers (which includes the VX800/8i...a built-in 8-channel amplifier with 10-channels of DSP Processing, with digital Toslink Optical input, 24/96 internal processing. They also have a standalone 8-channel DSP called the TwK. Using the *TüN 4.x* software combined with the *VXi* DSP amplifiers or *TwK* DSP, you can apply manual corrections OR "Auto-Tune" corrections (if you wish) using the measurements that you perform which will automatically apply the corrections to their DSPs in real-time. This includes AllPass filters. I know that you obviously already have your DSPs and Amplifiers, but you might be interested in the FREE *TüN* software. The results of their "Auto-Tune" corrections are provided so that you can input them into just about any DSP. But the real power is the real-time phase response visualizations of Smaart 8 that you get for free. You can find excellent, in-depth tutorials for this software and hardware on the *JL Audio* KZbin channel.

[@Aswaguespack]

You have answered some questions I have been wondering about. I have only a basic knowledge of DSP and seeing you walk through these steps helps me understand that process a bit better. How much amplifier power is feeding each of the drivers in the system?

[@IBuildIt]

100 watts for each of the speaker drivers and around 150 watts for each of the four subs.

[@kennethfarquhar8518]

@@IBuildIt what class amplification is implemented? All the same from tweeters to woofers and sub woofer . For instance class A, od class A/B across the board or A on the tweet , cladding D for subs . Just curious. Also was wondering g the woofer brand in your open baffle beauties ? Thanks so much for all your videos !!!

[@tubeelectron13]

Hello John, it’s very nice work and so measurments it’s a thing but lithenning it’s an other thing! Can we listhen your open baffles in new video ?

[@IBuildIt]

I made a recording of these and put it at the end of the build video: kzbin.info/www/bejne/oWWuf3SKZdVqhZY

[@Koru-Health]

Could you use the results from mini DSP and successfully translate them into a passive crossover design with identical results?

[@johankamarudin5155]

Definitely can. But with a decent components.

[@johankamarudin5155]

Definitely. That is one of the purposes of using dsp actually

[@sentinelvc9695]

In the interface, it looks like we have 10 channels (8 analog 2 digital) allowing up to 5 a way crossover. You run four 12s outside the enclosure- but those could theoretically be internal with some sort of internal digital converter? Also, the 4x10 is the 4x8 with a $ 10 USD software upgrade from miniDSP website?

[@sentinelvc9695]

Few more details on the amp? I just read the description- no need to answer my first question!

[@hazembata]

Do these speakers have passive crossovers as well? Can you show the entire setup and walk us through it? Trying to wrap my ahead around using a DSP. Thanks.

[@johankamarudin5155]

No. The dsp is doing all the passive does. Some people use dsp to design a loudspeaker xover. When they get all the setup right, they will build the passive xover for that loudspeaker.

[@Nightjar726]

Is this using only one power amplifier? How do you connect the drivers? Different connection for each? Thanks

[@johankamarudin5155]

Multi channel power amp of course.

[@TriAmpMyFi]

Very nice. 🔈🔉🔊

[@Sven-ola]

Question :) I built myself a couple of openbaffle speakers, I got a pair of minidsp 2x4 and hooked it all up, my problem is this noice, it comes from the minidsp, white noice from fullrange driver, So I had to go whithout dsp on that driver becourse of the noice... now I would like to experiment whith a tweeter, but I cant use my dsp, is yourse noicy? or can I get a better dsp? Its ok in my bass driver but whey play under 500Hz, but over 1000Hz and up its unbareble to listen to that white noice :/ any ideas? Love youre vids ! Cheers from Sweden!

[@dmitriypleskach9742]

Когда сможем послушать?

[@gregnewberry4813]

Nice video. John, I always thought that with more than one sub they had to be either very close, or up to 50ft apart to eliminate phase cancellation at lower frequencies? How does that work in a listening room like yours?

[@misterwireless5700]

Did you reduce the input before adding gain to avoid clipping?

[@KipdoesStuff]

I can follow most of what you are doing but I couldn't apply this knowledge to anything. I just set the sliders on my eq to a happy smiley face or a grumpy face. :) :(

[@abdo-dr1tu]

Why are your crossovers so aggressive? You might be increasing group delay for no audible benefit.

[@sorgunakkor1585]

How is the noise level on the MiniDSP crossover? Mine is a bit noisy on the high end.

[@IBuildIt]

Below audibility on mine.

[@UberAlphaSirus]

It may well be the power supply.

[@willleavitt7156]

I’ve had the same problem with two different Mini DSP’s , balanced. Hiss from the tweeters. Annoying as hell. If you have adjustable amplifier gain turn it down a bit. If not it may not work for you.

[@tee-jaythestereo-bargainph2120]

Why can't you be my neighbor ! Love the videos thank you

[@mrpres17]

What did you end up fine tuning to make them measure better?

[@jaiaditya4u]

I was the 606 person to watch your video. Thanks.