Review and Measurements of miniDSP SHD DAC, DSP And Streamer

[Deleted member 2944]

Anything one can do about the latency in a HT set up?

It depends upon how bothered you are by lip-syncing issues and if you have facility elsewhere in your system to correct it. (Assuming adding even further delay in the miniDSP unit won't correct it.)
Personally, lip-syncing issues irritate the shit out of me. But, I never intended to use this unit in an HT environment, so it doesn't bother me here.

Dave.

 

[Bamyasi]

Would that fact that I've actually seen two AK4490 chips inside my own unit convince you?

That sounds reassuring indeed

I was always wondering why so many manufacturers make potential customers go through loops in order to figure out what they are buying, instead of just list all essential details in the documentation? Obviously, any company not disclosing clearly what they are selling looks suspicious and with the fierce competition in the field this might as well play very strongly against them. So why so many companies still do this?

Sorry about this philosophical digression and thank you for your help!

 

[Bamyasi]

^I and many others are very happy with just the modestly priced minidsp 2X4HD, which would suit your needs with a 2.1 system well. It doesn't support Dirac, but do you really need that? Pretty normal manual IIR PEQ works well, and it understands FIR too. With REW and eg. rePhase you can semi-automatically create filter settings and have same effects as Dirac.

Initially I thought about simply buying an outboard crossover like dbx 223sx but then read about all the room correction business and thought maybe I should give it a try and miniDSP 2x4HD indeed was the device I was eyeing. But then I saw Amir's review of the miniDSP SHD and got interested in the whole Dirac thing as well. Doing more research on the net showed that there is sort of ongoing controversy about which approach is better: IIR, FIR, Dirac or simple PEQ, etc. Obviously, I've got completely confused at this point. Will have to continue researching it I guess.

 

[Deleted member 2944]

I was always wondering why so many manufacturers make potential customers go through loops in order to figure out what they are buying, instead of just list all essential details in the documentation? Obviously, any company not disclosing clearly what they are selling looks suspicious and with the fierce competition in the field this might as well play very strongly against them. So why so many companies still do this?

I'm not sure what essential details you think are missing with the SHD information and what they should be disclosing that they're not. To label this as "suspicious" is just silly.

Their "product brief" on this unit identifies more of the inner workings and hardware specifications than most manufacturers would offer on similar products. DSP type, ADC/DAC chip complement, op-amp types, etc, etc, is all there. They also give a good specification of the various voltage levels, input/output impedances, etc, etc.

https://www.minidsp.com/images/documents/Product Brief-SHD.pdf

Dave.

 

[Bamyasi]

I'm not sure what essential details you think are missing with the SHD information and what they should be disclosing that they're not. To label this as "suspicious" is just silly.

Their "product brief" on this unit identifies more of the inner workings and hardware specifications than most manufacturers would offer on similar products. DSP type, ADC/DAC chip complement, op-amp types, etc, etc, is all there. They also give a good specification of the various voltage levels, input/output impedances, etc, etc.

https://www.minidsp.com/images/documents/Product Brief-SHD.pdf

Maybe it sounds silly, I agree. However, there was a disclaimer in my post that it was a general thought, not necessarily related to a particular issue with the SHD documentation.

But it would be nice if the documentation says explicitly "2 x AK4490EQ DACs" instead of a vague phrase "we’ve added a second pair of outputs" which left one wondering what exactly and how was added. miniDSP also does not say which kind of ADC/DACs are used in their other prodcuts and do not publish THD/SINAD numbers for them, so it is hard to compare, say 2x4HD vs DDRC-24 vs SHD performance. Definitely not the worst technical documentation I've seen but not without problems either.

Note, there is nothing about the op-amps used in the technical brief you have linked. Not that I needed this sort of details but anyway.

 

[typericey]

For someone who wants to dip his toes into the room correction/DSP realm, would miniDSP products including this SHD be a good place to start?

Asking for a friend.

 

[Rja4000]

For someone who wants to dip his toes into the room correction/DSP realm, would miniDSP products including this SHD be a good place to start?

Asking for a friend.

If you want to remain in digital domain only, the older miniDsp DDRC-22D is now cheaper than before and also includes Dirac and remote control.
There is no streamer nor any analog I/Os, but I have one and it performs well.

 

[col1n]

I'm interested in the Dirac approach for vinyl and 2-ch. digital streaming, and in how the SHD would connect into my system.

For vinyl, it looks like I would insert the SHD after the phono preamp.

The streamer (Squeezebox Touch) can connect via S/PDIF coax, optical or USB. Would the SHD provide USB audio (processed) to my existing DAC (Oppo UDP-205)? (The Oppo will also take coax or optical, but I'd prefer USB.) I'm hopeful that it would, based on the following from miniDSP, but not sure if I'm interpreting this info correctly:

- USB audio recording feature (4xCH processed output via USB audio to record inputs, e.g. Vinyl)

Hypothetically, if I had multiple analogue source, could the SHD work in my amp's "tape loop"? (In reality I probably wouldn't use it this way for listening to the Squeezebox, as the Oppo already performs DAC duties, but it would help me to understand potential use cases.)

Thanks in advance for advice.

Colin

EDIT - Just found their FAQ. Apparently it's not possible to connect a USB DAC to the SHD

 

[Dj7675]

Just an FYI regarding the Minidsp SHD, Dirac 2 has been released. In addition, in their newsletter they also mention an exciting new streaming option. I’m hoping for Roon, but we will see.
https://www.minidsp.com/aboutus/newsletter/listid-1/mailid-71-minidsp-q3-2019-newsletter

 

[BeepPeep_61]

Happy Sunday to all,
I have a question for Armir (which I thank deeply for the very great and very interesting work done), in your conclusions on the MiniDSP SDH, regarding the measurement of jitter and noise. You write:
"Better power supply decoupling and shielding would go a long way toward better performance".
I have just purchased this device, and I wanted to ask you if you would recommend making a 24V DC linear low ripple power supply in an external cabinet to replace the power supply from the original switching type inside the MiniDSP.
In your opinion, could this change improve the situation displayed in the jitter and noise graph?
Thanks
Gigi

 

[DNM]

Why bother when the jitter is at or below -120db?

 

[BeepPeep_61]

A couple of other measurements before I send the unit back.

First, testing S/PDIF input and Balanced output to see if jitter changes:

View attachment 15903

As noted on the graph, the response is almost identical. So this is intrinsic to the unit and internally generated noise and jitter interference.

Excuse me for repeating the message but I hope that in this way Armir will see it !!
I have a question for Armir (which I thank deeply for the very great and very interesting work done), in your conclusions on the MiniDSP SDH, regarding the measurement of jitter and noise. You write:
"Better power supply decoupling and shielding would go a long way toward better performance".
I have just purchased this device, and I wanted to ask you if you would recommend making a 24V DC linear low ripple power supply in an external cabinet to replace the power supply from the original switching type inside the MiniDSP.
In your opinion, could this change improve the situation displayed in the jitter and noise graph?
Thanks
Gigi

 

[Dj7675]

For those using the minidsp shd or those interested, the Minidsp SHD, roon is now officially supported. To enable, first update by going to settings>system>check for update>then apply the update. Then
go to... Settings>My Music and then under the "functionalities control" there is an on/off for roon ready. Seems to work ffine. The only thing I haven't figured out is the volume appears to be fixed. Not sure if there is another setting somewhere or if this is how it is or not, but I have sent minidsp a support ticket to find out.

 

[DNM]

For those using the minidsp shd or those interested, the Minidsp SHD, roon is now officially supported. To enable, first update by going to settings>system>check for update>then apply the update. Then
go to... Settings>My Music and then under the "functionalities control" there is an on/off for roon ready. Seems to work ffine. The only thing I haven't figured out is the volume appears to be fixed. Not sure if there is another setting somewhere or if this is how it is or not, but I have sent minidsp a support ticket to find out.

This is good news but doesn't sound like an official Roon Ready release. MiniDSP would normally make a big announcement about something like this but they don't appear to have done so. Neither have Roon.

 

[DNM]

Yep, defo not official, its using AirPlay, not Roon RAAT. Works fine though.

 

[Dj7675]

Yep, defo not official, its using AirPlay, not Roon RAAT. Works fine though.

View attachment 35781

If you upgrade the just released Volumio, it is roon ready.

 

[DNM]

Ah, I hadn't enabled Roon Ready in Volumio. Its appearing under 'Networked' now and running Roon RAAT which is good. But as you can see its "uncertified" which means it's not official and I would hope the official version will allow volume control of the SHD's DAC within Roon, which it currently doesn't.

Hopefully this means the official version is close. Thanks for the heads up.

 

[Jukka]

But it would be nice if the documentation says explicitly "2 x AK4490EQ DACs" instead of a vague phrase "we’ve added a second pair of outputs" which left one wondering what exactly and how was added. miniDSP also does not say which kind of ADC/DACs are used in their other prodcuts and do not publish THD/SINAD numbers for them, so it is hard to compare, say 2x4HD vs DDRC-24 vs SHD performance. Definitely not the worst technical documentation I've seen but not without problems either.

This is valid point. Some of the pro usb interfaces (discussion on the other topic) state in their specs that THD+N is for outputs 1+2 only and outputs 3+4 are of lesser quality, for example no power on pop control. I hope this is not the case with miniDSP SHD. It would be great if @amirm would check in future measurements that all channels are up to spec. Measuring the "last" channels on addition to the "first" channels is probably enough, if time is critical.

 

[Dj7675]

Ah, I hadn't enabled Roon Ready in Volumio. Its appearing under 'Networked' now and running Roon RAAT which is good. But as you can see its "uncertified" which means it's not official and I would hope the official version will allow volume control of the SHD's DAC within Roon, which it currently doesn't.

Hopefully this means the official version is close. Thanks for the heads up.

View attachment 35789

Just heard back from Minidsp:
1-They have submitted to Roon for certification
2-Once approved there will be a new firmware which will allow volume control. Volume control via Roon will be adjusted through the master volume control in the minidsp.

 

[DNM]

Just heard back from Minidsp:
1-They have submitted to Roon for certification
2-Once approved there will be a new firmware which will allow volume control. Volume control via Roon will be adjusted through the master volume control in the minidsp.

Great, thanks for the update. This is how they indicated it would work. Looking forward to loosing the remote!