Recommendations needed for a replacement for a miniDSP active crossover

[dualazmak]

Hello again, dear OP,

Even though we definitely need intensive microphone measurements, near field and at our listening position in our room acoustics, in the final stage of XO(Fq, slopes, type of filters)__EQ(if needed)__Delay(time-alignment)__PhaseReverse(inversion) tuning, we should and we can trust our ears and brain at the final stage(s) of our audio exploration, then our final measurement(s) would hopefully just confirm and support your subjective final tune-up, as I recently wrote here.

And,,, the flat (or near flat) Fq response would not always gives us best subjective sensation and/or best subjective sound quality since subjective impression/feeling greatly varies depending on characteristics of SP drivers and our complex room modes/acoustics at listening position.

And our hearing ability (age dependent hearing decline, more or less) would also somewhat "matter", I assume. Whether we would compensate it by relative gain controls for SP drivers (similar to tone control) or not would be fully your choice and preference (ref. here).

I do hope much good luck in your audio gradeup project. I believe you would very much enjoy it and lean a lot through it; you can be always relaxed since many of ASR colleagues will be more that happy to assist/help you on the way once you would decide and share which path and direction to go.

 

[Old Hi-Fi Guy]

That sounds like an unusually small three-way...one with a sub driver 8" or less, unlless maybe on a sloped baffle ???
......3-4" depth differences between acoustic center is pretty tight.......


Haha...you're not so old as you allude to...
Or rather I should say, these contemplations keep this old goat in his 70's, awake occasionally too.

Well spotted - each speaker uses two 6.5" woofers in order to reduce the width of the baffle.

I'm not far behind you!

 

[Old Hi-Fi Guy]

Hello again, dear OP,

And our hearing ability (age dependent hearing decline, more or less) would also somewhat "matter", I assume. Whether we would compensate it by relative gain controls for SP drivers (similar to tone control) or not would be fully your choice and preference (ref. here).

Your assumption is correct and is why those of us of advanced years can not rely on our ears, except to tell us when something is wrong with them. When your system starts sounding rather dull and lifeless, it's time to get your ears checked for wax and your hearing tested for the typical high-end roll-off that comes with age.

The solution for me is to produce a generally flat FR by measurement, but with a slight roll-off towards the top end, and then to ask my wife and a friend - both of whom have excellent hearing - to listen to a few test tracks. When I think the FR is about right, I use music to help me to tell my audiologist when she's got my hearing aids right. So I do use my ears, but not in the way that is usually meant.

Incidentally, I would like to check out the audiology software you mention in the last link in your post - do you have a reference?

 

[dualazmak]

Incidentally, I would like to check out the audiology software you mention in the last link in your post - do you have a reference?

Sorry, I usually use very simple and convenient online web hearing test which my friend otorhinolaryngologist recommended me for simple
weekly test;
https://www.signia.net/en/service/hearing-test/
I just tested it at my office (not perfectly quiet, though) with my headphones (in almost max gain as suggested by the preparatory part of the web test) ; fortunately the result is;

I sometimes also use more advanced audiometer software but it is only in Japanese language and can run on Windows 11 of Japanese setup.
I believe you can find suitable and rather advanced free online (web tool) or off-line audiometer software by web search.

Twice in a year, I visit my that friend otorhinolaryngologist's clinic (he is one of my audiophile friends) for detailed precise hearing test over 10 Hz to 22 kHz; this is highly recommended for you too!

 

[dualazmak]

The solution for me is to produce a generally flat FR by measurement, but with a slight roll-off towards the top end, and then to ask my wife and a friend - both of whom have excellent hearing - to listen to a few test tracks. When I think the FR is about right, I use music to help me to tell my audiologist when she's got my hearing aids right. So I do use my ears, but not in the way that is usually meant.

Yes, I can understand well your point, even though I myself fortunately have fairly nice hearing ability beyond the average of my age group.

And, our discussion point here is one of the main reasons that I have implemented "safe and flexible on-the-fly (while listening to music) gain controls" for my SP drivers especially supertweeters, as I shared in detail in my post here and here. I believe this feature would be one of the invaluable pros/merits of DSP-based multichannel multi-driver multi-amplifier fully active audio setup.

 

[Old Hi-Fi Guy]

Sorry, I usually use very simple and convenient online web hearing test which my friend otorhinolaryngologist recommended me for simple
weekly test;
https://www.signia.net/en/service/hearing-test/
I just tested it at my office (not perfectly quiet, though) with my headphones (in almost max gain as suggested by the preparatory part of the web test) ; fortunately the result is;
View attachment 320077


I sometimes also use more advanced audiometer software but it is only in Japanese language and can run on Windows 11 of Japanese setup.
I believe you can find suitable and rather advanced free on-line (web tool) or off-line audiometer software by web search.

Twice in a year, I visit my that friend otorhinolaryngologist's clinic (he is one of my audiophile friends) for detailed precise hearing test over 10 Hz to 22 kHz; this is highly recommended for you too!

Sadly, I can no longer hear anything over 10 kHz (and probably considerably less).

 

[dualazmak]

Sadly, I can no longer hear anything over 10 kHz (and probably considerably less).

"Sadly?!", no not at all; I believe you can still very much enjoy music if you can hear up to around 5 kHz or 7 kHz. Several of my audiophile friends have similar hearing decline like you, but they are very much enjoying their audio enthu life of DIY audio and intensively enjoying listening to their preferred music using very unique really HiFi setups.

 

[3ll3d00d]

When we start introducing delays through the use of DSP filters, what sort of magnitude are they (again, for multiple drivers in a single box)?

If the same device is applying the filters to all channels then there is no difference in delay, just different filters (with correspondingly different phase responses)

 

[Old Hi-Fi Guy]

If the same device is applying the filters to all channels then there is no difference in delay, just different filters (with correspondingly different phase responses)

Just to be clear, I'm not talking about room corrections.

So if one channel has more, or more complex, filters than another channel, this won't create additional delay for that channel?

 

[ernestcarl]

Just to be clear, I'm not talking about room corrections.

So if one channel has more, or more complex, filters than another channel, this won't create additional delay for that channel?

If you are applying a chain of plugins or software/hardware processing then that really depends on the total accumulated latency/delay. One can create fairly detailed EQ with reasonably low latency:

Speaker ported vs plugged?

Ported or Plugged (sealed)... Not only the SPL but also the transient behaviors, especially the woofer's (and sub-woofer's) transient behaviors, are affected. Generally speaking, in plugged (sealed) cabinet, the inner air reacts as damper or shock-absorber (so sometimes called as "air...

www.audiosciencereview.com

I think that example has about ~3.4ms for the miniDSP itself and 10.67ms latency for the FIR filter = ~14ms delay (where there's no additional delay required for the main center channel speaker).

 

[gnarly]

Edit:Regarding delays,as it seems some people think is a big deal,here's the dirt cheap,almost legacy (all analog) behringer cx3400 (about 150 euro) which amongst it's gazillion tweaks includes delays also:

Behringer CX3400 Super X Pro V2

Active Crossover 2 Respectively: 3-Way stereo or 4-way mono, 24 dB / octave Linkwitz-Riley filter, Mono-Sub switchable, LF / HF gain regular / mutable, CD horn EQ switchable, Vertex frequency tunable, Factor switching (10x), Multi-band limiter...

www.thomann.de

Thanks for reminding me I still have a cx2300, the little brother to the cx3400 ....that I haven't used in over 20 years.
Just to see, I pulled it out to run some transfers, and check out its features.
Works fine, basic as it gets, xover..

Crazily I see both models have an adjustable delay on the LOW sections only. Worthless imo.
I've never encountered a need to delay lows.

 

[Sokel]

Crazily I see both models have an adjustable delay on the LOW sections only. Worthless imo.
I've never encountered a need to delay lows.

Don't forget it's age,more than 20 yo maybe.
Their delays are not for subs,probably more to compensate for the lengths of the mid and hi horn in a typical 2/3 way pro speaker of that time (or older).

 

[gnarly]

My experience with delays between driver sections is that they are correct when they equal the physical distances between drivers' acoustic centers.

When driver sections achieve complementary acoustic coupling, is really doesn't matter what order the crossover is.
The needed delay won't change from that physical distance.
And given that the range of crossover frequencies that can be used to achieve acoustic complementary coupling is usually pretty narrow, acoustic centers move very little with different chosen xover points, if at all.

Ime/imo, there is really only one correct set of delays between sections, and it's independent of the particular filters used....IF the speaker has the drivers set up correctly, which means complementary acoustic summations.
And it's the same set of delays for either IIR or FIR xovers.

 

[gnarly]

Don't forget it's age,more than 20 yo maybe.
Their delays are not for subs,probably more to compensate for the lengths of the mid and hi horn in a typical 2/3 way pro speaker of that time (or older).

Yep...maybe.
It's just even on old pro boxes like you describe, I've always found a need to delay the highs.

 

[Sokel]

Yep...maybe.
It's just even on old pro boxes like you describe, I've always found a need to delay the highs.

Like this one I guess,and the intended use probably.

(Renkus-Heinz ST4,a real bad boy)

 

[gnarly]

Like this one I guess,and the intended use probably.
View attachment 320178

(Renkus-Heinz ST4,a real bad boy)

Good example. Renkus-Heinz has made some really cool, innovative boxes imo.

 

[3ll3d00d]

So if one channel has more, or more complex, filters than another channel, this won't create additional delay for that channel?

I wasn't talking about room correction either, I was talking in the context of use of IIR filters. If you add an arbitrarily complex filter pipeline with a variety of different steps using different techniques (such as mixing non minimum phase FIR and IIR) on different channels then all bets are off. All of this is measurable though so not a big deal regardless (as if you can implement such arbitrarily complex filter pipelines then a bit of delay isn't going to be a problem)

 

[Sokel]

Good example. Renkus-Heinz has made some really cool, innovative boxes imo.

I have listened to them in a really nice 10-seat HC,about 90 m² made from ground up along with their subs (all invisible) and the experience was...
It's not only about level which was realistic (thunderstorm-like),they have an unusual clarity too (I'm talking about MC classical music,not film)
And the price is not bad at all ,about 5-6k each if I remember well.

 

[withoutsuit]

Is there anything that you would recommend for this application? I don't mind spending a bit more if it does a good job and I don't have to find a teenager to set it up for me.

Thanks!

May I ask in which country you live? Maybe the Nubert Nucontrol 2 would be an option, but It's a German manufacturer.

 

[voodooless]

May I ask in which country you live? Maybe the Nubert Nucontrol 2 would be an option,

How would that be a useful option?