I bought a MiniDSP 4x10HD a while ago when I built the Linkwitz LXmini+2's and have performed some modifications and optimization.
Firstly I removed the output coupling caps and added wire links as the caps are electrolytic and not biased so will most likely be generating higher distortion. I have circled the caps in RED that I removed. Also before removing the caps I checked DC offset which was negligible. The other option is to replace the EC's with MKP's or other film caps.
After living with MiniDSP for a while I found that my MiniDSP 4x10HD was clipping at the input on SPDIF and AES but not TOSLINK. To fix this I have lowered the input gain to -6dB and increased the output gain +3dB across all 4 outputs.
What I did was to decrease input gain until loud passages did not clip the input monitor, then I increased output gain until the subwoofer just clipped and backed off until no clipping occurred, then adjusted the other 3 outputs with the same additional gain as the subwoofer.
I plan to bypass the internal output DAC's using the I2S header on the PCB at some point in the future, but the shortage of components has made sourcing high quality I2S / DAC harder to come by.
Firstly I removed the output coupling caps and added wire links as the caps are electrolytic and not biased so will most likely be generating higher distortion. I have circled the caps in RED that I removed. Also before removing the caps I checked DC offset which was negligible. The other option is to replace the EC's with MKP's or other film caps.
After living with MiniDSP for a while I found that my MiniDSP 4x10HD was clipping at the input on SPDIF and AES but not TOSLINK. To fix this I have lowered the input gain to -6dB and increased the output gain +3dB across all 4 outputs.
What I did was to decrease input gain until loud passages did not clip the input monitor, then I increased output gain until the subwoofer just clipped and backed off until no clipping occurred, then adjusted the other 3 outputs with the same additional gain as the subwoofer.
I plan to bypass the internal output DAC's using the I2S header on the PCB at some point in the future, but the shortage of components has made sourcing high quality I2S / DAC harder to come by.
I've been using the 4x10 in a three way active setup for a few years now. I've been trying to find the next upgrade for an 8ch DSP/DAC but not many solutions. I've always been hesitant to attempt a mod as I have no immediate backup and could not be without my system for long. Looking forward to hear more about integrating with the I2S. Would you mind highlighting the header pins so I can have a closer look at mine next time I lift the hood?
What do you think about potential mods to the power supply components? I've been powering mine with an Sotm SPS500 supply.
What do you think about potential mods to the power supply components? I've been powering mine with an Sotm SPS500 supply.
I too looked for a solution to a 4 way crossover and there is not very much available and what is out there is very expensive. A friend of mine uses the NanoDIGI which is 2x8 digital in and out but this is NLA and MiniDSP's replacement is the Flex which is only 2x4, so totally useless.
At the front left of the PCB under the ribbon cable is a 30 pin header with another to the left of it these contain the I2S input/output pins. I can't remember which is which off the top of my head, but MiniDSP used to have an I2S PCB so there is documentation on which pins are which.
The MiniDSP's all have onboard SMSP so powering them with LPS is not going to gain anything. The SMPS is on trhe RHS of the PCB (in the pic) between the large EC's.
At the front left of the PCB under the ribbon cable is a 30 pin header with another to the left of it these contain the I2S input/output pins. I can't remember which is which off the top of my head, but MiniDSP used to have an I2S PCB so there is documentation on which pins are which.
The MiniDSP's all have onboard SMSP so powering them with LPS is not going to gain anything. The SMPS is on trhe RHS of the PCB (in the pic) between the large EC's.
This is something I thought might be possible a couple of years back but apparently it is not. I do the occasional search to see if someone has found a non destructive (read: easy) method to do it but it seems not. The devteam over at MiniDSP have condemned the idea a few times on their forum:
https://www.minidsp.com/forum/hardware-support/12499-10x10hd-using-off-board-output-dacs
"No such thing as getting digital out to DAC with the 10x10. The nanoDIGI is the only platform with multichannel support for SPDIF."
It's very frustrating as the Flex is a couple of channels short for what I want and they discontinued the NanoDIGI so the dream is scuppered!
Do keep us updated on any progress though 🙂
A friend of mine has a MiniDSP car audio 8x12 that has had the internal DAC's bypassed by taking the I2S to higher quality external units with better analog driver section so it's doable. Whether it's worth the effort is the other question.
This are exactly what I need albeit a little more expensive than MiniDPS. But due to component shortages are unavailable
https://analog-precision.com/
This are exactly what I need albeit a little more expensive than MiniDPS. But due to component shortages are unavailable
https://analog-precision.com/