Buy new DSP for multi subwoofer system

[Niklasmagnus]

Hello
I need to buy a DSP for my multi (4) sub system.
My system:
NAD T777 v3 (sub preout unbalanced) - miniDSP 2x4 balanced - 2 pcs Behringer A800 (input balanced)

I just sold my minidsp since I got a good deal, so now I need to replace it. I´ve been looking at the newer miniDSP 2x4 HD version since it´s unbalanced and I did have some problems with noise floor using the older 2x4 bal., in my point of view and troubleshooting due to mixing unbalanced and balanced from NAD to minidsp or just bad (too little knowledge) gain structure.
But the miniDSP 2x4HD is ~300 dollars so I´ve been searching the internet for alternatives and found the t.racks DSP 4x4 mini, ~100 dollars. Its unbalanced though, but maybe will work better with my NAD. Unfortunately fewer PEQ band to play with but I guess you get what you pay. I´ve been running MSO software to set up the subs using 6 bands with good results so don´t see the need for 20 band (or something like that) in the 2x4hd.
Any suggestions?

Thanks!

 

[kiwifi]

Quite a few DSP options on AliExpress, for example...

US $192.06 ShennDare ai408 4 Input 8 Output 32-bit DSP Digital Audio Processor Professional Speaker Management System Audio Processor https://a.aliexpress.com/_mMUJity

 

[Niklasmagnus]

Okey thanks.
I did some testing by connecting receiver pre-out directly to sub power amp (Behringer A800) to rca input and 6,3mm input with rca adapter and I get same noise as before when using minidsp 2x4 bal. Just that gain knob is pointing at different “clock” when getting same dB output running test tone. The delta dB is same between test tone and “mute”=noise floor.
No change in noise dB when changing volume at receive, only with increasing/ decreasing gain at amp.
And I have same problem on SUB 2 pre-out and FL pre-out. Maybe it’s grounding noise, I don’t know how that sound or if this is something else.

Any suggestions before I order a DSP?

 

[HarmonicTHD]

Okey thanks.
I did some testing by connecting receiver pre-out directly to sub power amp (Behringer A800) to rca input and 6,3mm input with rca adapter and I get same noise as before when using minidsp 2x4 bal. Just that gain knob is pointing at different “clock” when getting same dB output running test tone. The delta dB is same between test tone and “mute”=noise floor.
No change in noise dB when changing volume at receive, only with increasing/ decreasing gain at amp.
And I have same problem on SUB 2 pre-out and FL pre-out. Maybe it’s grounding noise, I don’t know how that sound or if this is something else.

Any suggestions before I order a DSP?

Noise or better hum from ground is at either 50 or 60Hz depending on your countries energy grid.

 

[Niklasmagnus]

Noise or better hum from ground is at either 50 or 60Hz depending on your countries energy grid.

I did a RTA measuring and found that 50, 100, 200 Hz are dominant so it looks like a ground loop issue. I did place an order for the DSP 4x4 mini but will also order a DI box with gnd lift and hopefully it will fix the problem.

 

[datrumole]

...But the miniDSP 2x4HD is ~300 dollars so I´ve been searching the internet for alternatives and found the t.racks DSP 4x4 mini, ~100 dollars. Its unbalanced though, but maybe will work better with my NAD. ...

unless i'm misreading, the 4x4 mini is balanced, i'd make sure your gear is going to be able to work with it properly

you may be able to mod it with a sparkfun THAT 1646 which will do unbal to bal conversions