T.racks 4x4 miniDSP undressed

I just received my "Thomann T.racks 4x4 Mini DSP".
These sell in Germany and most of Europe for €119 inc. P&P.
For those frustrated by ADAU 1701 boards like the Sure/Wondom or miniDSP, this may be the thing to get what they expected from a low cost DSP.
By the way, I have some of the DSP boards that need Sigma Studio.

The T.racks 4x4 Mini DSP comes with a Windows software and plugs into USB. No messing around with Cypress interfaces and Sigma Studio Software (which is great if you like mighty, complicated things). just what you would expect from Plug&Play.

The software has all you may need for an active speaker, 2.1 setup or even a small PA system. For the last one IMO it is a must have.

To show you what you get for such littlel money, I made a bunch of pictures. Quite some value compared to others.

The case is steel and aluminum, seems close to indestructable.

PS I have no connections to "Thomann"


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Thanks. There’s a dearth of information online about this product so thank you for doing an undressing.

Adding to my cart now…

Please give us some feedback/ comments screenshot of the software, and compare/contrast with what others you may have experienced with.

Finally, and measurements of the ADC/DAC would be welcome.
 
You can download the software and use it in DEMO mode. For those interested:
https://images.static-thomann.de/pi...e_t.racks_dsp_4x4_mini_editor_v1.05_setup.exe

The software runs without any problems and contains most you may need. I need a balanced output, which makes it a match for me, but can be driven unbalanced as well.

The value of the hardware, compared to the other "low cost" ADAU products without acceptable user interface, is impressive.

I did not have time to measure, but expect noting unusual. It has been on the market for over 3 years now and there are no known problems so far. The PA community is quite picky...

Have a look into the user manual:
https://images.static-thomann.de/pi...nt/manual/448459_c_448459_v2_r1_en_online.pdf

Frequency response 20 Hz … 20 kHz –0.3 dB Total harmonic distortion (THD) < 0.008 % (1 kHz, 0 dBu) Signal-to-noise ratio > 105 dBu Crosstalk > 70 dBu 20 Hz … 20 kHz Digital signal processor 32 bit A/D-D/A converter 24 bit Sampling rate 48 kHz
 
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I own two, bought them for 77 Eur each back then:) They are really handy - I used them for quite some time for my 4 way horn stack, which is currently dismantled. The only thing I do not like is that you can get some funny noises at turn on and turn off, so the right turn on/off sequence must be done to avoid this. This might have gotten better with the latest upgrade, but I do not want to risk my speaker health to try.
 
Such devices are always made for operators with some very basic technical education. Just like cars in most countries are operated by licensed drivers which have a drivers license... which does not make all of them "car nuts".
Just as you have to find a gear in a car to get it moving, you need some matching cables and settings to make this device work. This art is not part of every ones knowledge. This explains the high acceptance of wireless devices, which can be operated by anyone, indpendent of education, like mobile phones and Kalashnikov guns. Since mobiles have become common, the number of accidental death by chocking from a telephone cables has become quite low. The development of Kalashnicov induced end of life numbers can not to be seen to develop that positive.

The amplified version is just the same DSP, in a larger casing with D-amp and SMPS. It is not high end HIFI, but quality sound for not too high power demands. It can be used as a sole DSP too, as it has line outputs. Non the less it does need some wires connected to produce noises.
 
Seem to use 2 x PCM5102A as DACs and PCM1802 as ADCs
Not sure about the DSP at all. If I can count it is a 64 package ... does not seem to be an AD device. The big ESMT chip is a 1M x 16 bit x 4 Banks SDRAM ...... ....
Is there markings on the DSP?

The funny noises at turn on/off is a bit strange as it is not that difficult to get the PCM5102A to stay quiet because of it's muting and anti pop circuits. But if they use buffers after the DAC, then this of course goes away .... is it ballanced out? .... then they for sure have to uses unbal to bal amps/buffers, which probably do not incorporate an good enough muting circuit .. it seems
 
What is suppose to be the DSP (64 legs chip on top) has it's markings removed professionally. The performance is like an ADAU1701.
I did not remove the stacked PCB, maybe there is more on the inside.
It may be something like an ADSP-BF592, would match the DACs and ADCs around it. At 3$ not too expensive.

I made these pictures, mainly to show how overpriced DSP boards like the Sure/ Wondom DSP are. This product gives you real value for your cash.

The outputs are balanced too, there seem to be some un/bal buffers. The "RT3609" IC I think is used for it, is from a Chinese company that does not hand out data of its components. It seems to be a large scale copy production, which allows Chinese producers to get around common TI parts, avoiding license fees. As anything in China is about...

The on off noise is only a problem for people seeking trouble. In any usual chain power amps are switched on as the last part and off as a first. I do not know how anyone can ignore this when buying a PA part.
You can't make it it fool proof, as some fool will find a work around anyway... also please see the price point, it was first offered for sub 90$!

If you install a muting circuit, it is the first thing an "audiophile" will cut out of his gear.

I did some measurements, this is boring stuff. It just does what it is supposed to do and distortion is as predicted, as far as my Focusrite 2i2 can measure. Curves and filters do exactly as supposed to do.

I'm building some active speakers, the plan is to use the 4x4 to find filters etc. Then, if done with the tuning, replicate them in Sigma Studio and use a cheap ADAU DAC in the final build.
 
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I just received a T.rack 4x4 and it does indeed seem to be a great value DSP and measures well with my Behringer UAC 222.
I'm using it for mid/woofer and tweeter crossover and PEQ room equalising.

I have a Dayton Audio DSP-LF for the sub which is also quite impressive, especially since it can be controlled by the I-woofer app.