thomann t.racks DSP 4x4 Mini Review

[rvsixer]

I had one, I would rather use one of those cheap Behringer equalisers. And I read a review somewhere of someone else who would as well and tried both with better results with the EQ. They were also a fraction of the price as well it's a shame they discontinued those. Those little EQs are better than those miniDSPs as well, another overhyped product.

Why take analogue and convert it to digital and then back to analogue again? I can get to adjust it but just buy an inline analogue EQ.

I love all the sarcasm here ...

 

[bennybbbx]

I love all the sarcasm here ...

his opinion is ok for the point when not want a subwoofer or a butt shaker or never want try out diffrent EQ settings and want easy compare which sound best. to get better sound out of subwoofer is usefull to have it. I also need delay my main speakers to subwoofer. I have no real subwoofer and use the jbl 104 as near field monitor 70 cm distance because they are coaxial and have the best directivity steareo image at this distance from all speakers i have. so i use the focal alpha 65 as the subwoofer back on my desktop and on the wall.

because there can not read much about damped room results i write much more to explain better.

I have damped my room around 2.5 meter width 2 meter height front and back wall and 3.5 meter x 2.5 meter ceiling with 5 cm basotect. my room is L size and i do only this region. this i find is key to HIFI heaven. on side i have very few damped. room sound not dull(this was my gretest fear) and bass is much more clarity and tighter and even the boom bass range i like. damping bring so much better sound, even when in nearfield 70 cm away and even my not subwoofer speakers are more than 70cm away from walls .I do not more, are ~18 qm damp material and cost around 380 eur. my whole room is 17 qm do all cost alot more money. but because of my tracks dsp i can get this 3 speakers work good together.

without the ability to compare diffrent correction i was not able to reach my hifi heaven. my subwoofer is around 1,8 meter away and speakers 70 cm. before i damp i hear that bass come from more behind even at low crossover freq. but now it is tight and great. also the jbl without sub sound as if it has lots more bass as before.
here are my dsp settings and the FR i get. because all together give the resulting sound i can tolerate more eq and diffrences until it find it bad in compare to headphone. now i think headphone are worser in compare and so i have hifi heaven . about the FR i think it is only around 4 db precise to measure. to get better precision need compare with headphone and look if the peaks in the measures in music are really louder as in a measured headphone or if you can hear a diffrence. i dont trust multi point measure software. but i use math room roomeq and measure and compare the diffrences. use dsp only and wide Q eq give better clarity

this is the jbl 104 without sub and no EQ. measure was not on same day a little diffrent microphone pos so fr is not good same as before

 

[rvsixer]

Great info, and exactly what these DSP devices are fantastic for.

But nothing yet about the analogue EQ devices that are better and cheaper and faster to implement this kind of thing than these overhyped ADC->DSP->DAC gizmos ...

 

[bennybbbx]

which analog EQ devices that are cheaper you mean ?. when use subwoofer need 2 EQ and delay. all 31 band eq cost over 120$ and so more expensive as the tracks mini. this low price stuff have very short potrange that are open and sooner or later get problem with dust. even if new it is not easy to set near same EQ level for left and right channel. and when use them longer there can assume pots crackle problems so left and right channels differ even more. 10 band graphic EQ are not so usefull. there is the larger behringer FBQ 6200 HD ultra graph. this cost over 200$ and need much space.

IF you like a blind test do with foobar abx blindtest then i can send you a song you like to test thru the dsp and record it with 24 bit. i dont believe that can hear diffrence even if there are AD DA AD converting. mostly diffrence happen when signal is at diffrent level as original . i make sure all signal is leveled that it is same.

 

[rvsixer]

which analog EQ devices that are cheaper you mean ?

I am not sure why the explanation and questions of DSP use to me. I am the one who sent this device in for testing, and understand it's use case.

Did you miss @Westsounds post, where he dismissed the value of these "overhyped" ADC->DSP->DAC devices and refers to an inline analogue EQ device as being cheaper and better to accomplish the types of tasks both you and I use DSP devices for?

I am waiting for his reply on this cheaper and better analog device, AFAIK it does not exist:
#120

 

[bennybbbx]

Great info, and exactly what these DSP devices are fantastic for.

But nothing yet about the analogue EQ devices that are better and cheaper and faster to implement this kind of thing than these overhyped ADC->DSP->DAC gizmos ...

and i thought you mean me with the second sentence
I search dsp behringer eq compare and i find this. there is talk about FBQ3102 cost around 170$ . the guy who own this is not so happy with his anlog. but can be a general problem. too much EQ change phase and results in weaker transients and this small bands bring even more trouble https://www.hometheatershack.com/threads/dsp-vs-analogue-eq.56842/

I have kirchhoff EQ available and i test out diffrent analog simulation. it is intresting because it show the curves of it. when choose a Q the result is often a much softer EQ as the digital have. so when choose digital Q2 in anlog you get it as Q 4 . there is trail version work forever add sometimes noise here https://www.threebodytech.com/en/products/kirchhoffeq so you can try out the high price analog eq and see the curves they do.

 

[rvsixer]

Alles klar ....

 

[Niklasmagnus]

I bought this DSP to use with MSO and my four subs. But so far its useless due to the rough settings in Peq filters and not able to take biquads.
Every value MSO calculate will be rounded to something else by the DSPminis software. I do a finial check tonight, but I guess It will be returned to Thomann and I buy a miniDSP 2x4 HD instead.

 

[rvsixer]

I bought this DSP to use with MSO and my four subs. But so far its useless due to the rough settings in Peq filters and not able to take biquads.
Every value MSO calculate will be rounded to something else by the DSPminis software. I do a finial check tonight, but I guess It will be returned to Thomann and I buy a miniDSP 2x4 HD instead.

That's unfortunate, as I want to use this in my new setup specifically for subs/flanking subs (which means having three input capability, leaving no solution available from miniDSP). The only other device I have found is the Dayton DSP-408 as a contender, but that gets mixed reviews.

Can you point out what was particularly "rough" about the PEQ? The Thomann can set center frequency and Q in 1/100 increments, and dB in 1/10 increments. What level of precision does MSO have, and in the end does any lack of said precision *really* make any difference (in either room measurements or audible to the listener)? Or is it that 7 PEQ filters are not enough to achieve the MSO filter?

Thanks.

 

[Niklasmagnus]

Blow are some och the steps in frequencies between 20 and 160 Hz. Maybe I´m over reacting. You can download the software and run it i demo mode.

the t.racks DSP 4x4 Mini

Compact 4-Channel DSP Inputs: 4x 6.3 mm jack balanced, Outputs: 6.3 mm jack balanced, Programming via USB (Windows), Power supply via external 12 V DC power adapter (centre positive), Weight: 0.6 kg, Dimensions: 160 x 150 x 40 mm, Incl. power...

www.thomann.de

161,2
157,5
153,9
150,4
146,9

101,5
99,2
96,9
94,7
92,6

61,1
59,7
58,3
57
55,7
54,4

40,3
39,4
38,5
37,6

22,1
21,6
21,1
20,6
20,1

 

[rvsixer]

Okay I am flying blind here, having not used MSO before. The numbers above appear to only have freq/gain info, and the gain not following what I would expect (center freq should have the highest absolute gain). FYI my previous sub tuning was always to find the best places for the subs via RTA sniffing with REW (place a sub in LP, sniff for good spot, place a sub there, repeat). This got me a good room response, and then just used the minidsp for final tweaking.

But in reading up on MSO, I found this question in a post (followed by the MSO developer response just below it), where you can spit out each subs freq/Q/gain PEQ settings. Also, did you set MSO for RBJ or "classic" PEQ (not sure which the thomann requires)?
https://www.avsforum.com/threads/mso-multi-sub-optimizer-tutorial-video.3206281/post-61450295

 

[Niklasmagnus]

I used the classic Q in the DSP mini. I´ve searched the internet for the correct answer to that question but did not find any reference that DSP mini use RBJ Q so I guessed its classic. But since I don´t get the predicted simulated result when measuring I will do a test tomorrow. Did not have time tonight.
You should check out Jeff Mery youtube tutorials, they are really good. He dont go higher then Q=8.651 to avoid introducing noise so I did the same but 8,5 (closest one), if I miss the center freq to much might be the reason for my bad results.

 

[bennybbbx]

Blow are some och the steps in frequencies between 20 and 160 Hz. Maybe I´m over reacting. You can download the software and run it i demo mode.

the t.racks DSP 4x4 Mini

Compact 4-Channel DSP Inputs: 4x 6.3 mm jack balanced, Outputs: 6.3 mm jack balanced, Programming via USB (Windows), Power supply via external 12 V DC power adapter (centre positive), Weight: 0.6 kg, Dimensions: 160 x 150 x 40 mm, Incl. power...

www.thomann.de

161,2
157,5
153,9
150,4
146,9

there ae more steps between 146.9 and 101.5. you can click on frequency and you can use cursor up down key to see all

if you need really such precise eq and lots of EQ bands you can hear on this testvideo

it play a testsong with a freeform eq and diffrent smoothing. i find the most smoothing sound best.

maybe you have a headphone that is test here. so you can correct the headphone to sound linear. then measure your speakers in REW add this settings as the beginning values in DSP.
now switch to mono and compare music when you hear headphone and then speakers. mono is usefull for that case because stereo space is much diffrent between headphone and speakers. now correct ntil sound simular. even if you not like e- guitar music it is good to check for good FR because on distortion guitar can hear missing or too much best. for example at 4 minutes

the guitar should not sound muddy. in headphone compare i use currently this correction and for left and right speaker i use little diffrence now

 

[Niklasmagnus]

there ae more steps between 146.9 and 101.5. you can click on frequency and you can use cursor up down key to see all

Not on my DSP mini, I did this and wrote down the steps i Hz.


Here are the simulation and result, Try5:

And config8:

Config8 is a bit tighter but have higher GD.

Maybe one cannot expect better finial measured result compared to simulation????
Or can one if possible to hit exact FR with correct Q and gain??

 

[bennybbbx]

Not on my DSP mini, I did this and wrote down the steps i Hz.


Here are the simulation and result, Try5:
View attachment 268281
View attachment 268284

And config8:
View attachment 268282
View attachment 268283

Config8 is a bit tighter but have higher GD.

View attachment 268290


Maybe one cannot expect better finial measured result compared to simulation????
Or can one if possible to hit exact FR with correct Q and gain??

this is with no speaker and you plug the dsp output to the input of your soundcard and input for rew measure AND use no cal file ? .this look really strange maybe you have a feedback loop or maybe your sweep time is too short. to get such a sweep measure impulse resolution you want . the Eq do not more as 12 db but you have more as 12 db which Eq settings you use on every try . I do verify it the next days when you tell me the parameters your tests use. I have done some tests some months ago.

the steps it have above 101,5 you not write
is
103,9
106.3
108.8
111.4
114.0
.........
i am too lazy to write more. it is not exact but it is fine enough to correct good. choose the nearest step.

 

[Niklasmagnus]

I have HDMI between PC and NAD T777 V3 receiver, and also use a Umik-1 USB mic.
You are correct about the steps above 101.5 Hz, I get same when stepping up with "key up". But it is 2,6 Hz between 111,4 and 114 Hz so you will miss the peak up to 1,3 Hz. If that´s an issue I´m not sure? Guess it depends on Q.

I have uploaded my MSO och REW files on link, if you want to have a look:
Files on my drive

 

[bennybbbx]

I have HDMI between PC and NAD T777 V3 receiver, and also use a Umik-1 USB mic.
You are correct about the steps above 101.5 Hz, I get same when stepping up with "key up". But it is 2,6 Hz between 111,4 and 114 Hz so you will miss the peak up to 1,3 Hz. If that´s an issue I´m not sure? Guess it depends on Q.

I have uploaded my MSO och REW files on link, if you want to have a look:
Files on my drive

In bass range ears are not very sensitiv. it is around 1 octave. smoothing that is more simular to ears you can choose in REW with graph menu on top and choose ERB or psychoacoustic . this you can enable and do correct. but best is when for final correction compare with headphone how i write in earlier post.

you can also change in rew EQ the values to that values the tracks dsp offer. then you see that there is no diffrence. have you hear the smoothing compare video. do you like the less smoothing sound more ?

if you try eq settings from rew and measure again and get not linear measures this is normal. place microphone 5 cm from hear position left or right it also change alot. hearing is very complex and the brain do lots of sound correction and also phase correction. I have around 18 qm basotek foam in my room and also get no perfect measure but overall it sound much better as undampet

 

[grogi.giant]

How can one connect the t.racks to unbalanced subs? Do the RCA adapters https://www.thomann.de/gb/the_sssnake_1820_adapter.htm do the trick? On the input side this should not be an issue, but on the output?

 

[rvsixer]

How can one connect the t.racks to unbalanced subs? Do the RCA adapters https://www.thomann.de/gb/the_sssnake_1820_adapter.htm do the trick? On the input side this should not be an issue, but on the output?

The linked adapter may or may not work, depending if your use case is okay with the balanced end having ring and sleeve tied together.

Pick your use case, match the adapter cable needed:
https://crookwood.com/blog/dealing-with-unbalanced-gear-in-the-studio/

 

[grogi.giant]

The linked adapter may or may not work, depending if your use case is okay with the balanced end having ring and sleeve tied together.

Pick your use case, match the adapter cable needed:
https://crookwood.com/blog/dealing-with-unbalanced-gear-in-the-studio/

That's why I am asking here, to figure out which use case I'm dealing with - which use case it is. 3 or 5.

Are the outputs of the T.racks 4x4 Mini floating balanced or hard balanced? The subs are floating unbalanced (PSU are double insulated, no mains ground present).

With floating balanced outputs you can use such adaptor, with hard balanced not at all and you'd cause a short.