• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required as is 20 years of participation in forums (not all true). Come here to have fun, be ready to be teased and not take online life too seriously. We now measure and review equipment for free! Click here for details.

miniDSP HD: unbalanced input usage

Joined
Feb 11, 2020
Messages
50
Likes
34
Location
N. Atlanta
#1
Thinking through a setup I'm planning.
Question - Is there any benefit to feeding the miniDSP with a digital input (from a laptop) vs feeding the miniDSP from the unbalanced output of a separate DAC? (Assume the other DAC is doing a much better job than the miniDSP and that the DAC does NOT have a digital output on it).

(DAC is used to feed headphone amp...for headphones. miniDSP is feeding amps for speakers)

The alternate plan is to feed both the miniDSP and DAC with the laptop's USB....but this would lose my ability to then use the DAC as a preamp for volume control.

and.....in using the unbalanced input on the miniDSP, does that in any way limit me from any of its functionality/features? (I'm guessing no)
 

stevenswall

Senior Member
Forum Donor
Joined
Dec 10, 2019
Messages
365
Likes
197
Location
Orem, UT
#2
Don't bother with the separate DAC... It's just an extra device with no audible advantage. Feed the MiniDSP HD from the laptop USB. Use any remote with the MiniDSP to control volume.

No, none of the inputs will limit the functions of the MiniDSP.
 
OP
ck42
Joined
Feb 11, 2020
Messages
50
Likes
34
Location
N. Atlanta
Thread Starter #3
One of the other things I'm trying to find out is if I feed a minDSP with an anlaog input, is it doing an A/D before it processes the signal (for Xover and other functions, and then another D/A out? Or is the analog input used for processing...in which case the miniDSP does no A/D or D/A at all?
 

stevenswall

Senior Member
Forum Donor
Joined
Dec 10, 2019
Messages
365
Likes
197
Location
Orem, UT
#4
All DSP products I know of that are modifying the signal will convert analogue inputs to digital, and then back to analogue if you're using that output.

That being said, these things are typically made so that it's done transparently.
 

Alobar

Member
Forum Donor
Joined
Jan 2, 2020
Messages
24
Likes
29
Location
Alaska
#5
If you wish to eliminate a ADC/DAC conversion, feel the mini digital. I did with my 4X10HD after I got the analog feed out of the chain and found it sounded better, (or so I thought).
 

exaudio

Member
Forum Donor
Joined
Jun 11, 2018
Messages
46
Likes
71
#6
From the manual:
One of the three stereo input sources is selected by the user and passed to the input channel processing blocks. The stereo analog input is converted to digital form. These blocks include input gain, level metering, and parametric EQ.

The processed input channels are fed into a 2-in 4-out routing matrix. The routing matrix enables the 2x4 HD to be used in a number of different applications. Section 6.4 provides a configuration guide for several common applications.

The outputs from the routing matrix are processed through a comprehensive set of DSP functions--crossover filters (high pass and low pass), parametric EQ, FIR filtering, and individual gain and delay adjustments. You can configure these as needed according to your particular application. Finally, the four output channels are converted to analog so they can be fed to your power amps and/or subwoofers.

2020-02-20_19-23-251080.png
 

RayDunzl

Major Contributor
Central Scrutinizer
Joined
Mar 9, 2016
Messages
9,962
Likes
8,380
Location
Riverview FL
#7
and.....in using the unbalanced input on the miniDSP, does that in any way limit me from any of its functionality/features? (I'm guessing no)
A 2x4HD?

I'd enhance their block diagram like this: (excuse my scribblins)

1582245383635.png
 

TomB19

Active Member
Joined
Oct 13, 2019
Messages
110
Likes
79
#9
The 2x4HD is a decent enough DAC. It's noticeably better than the old 2x4.

I would go the other way. The more DACs and devices you have in your signal path, the more you're going to have a mess of wires and a bunch of power bars and wall warts laying behind your system. It can get pretty gross with digital processing, IR remote extenders, network switches, etc.
 

phoenixdogfan

Addicted to Fun and Learning
Joined
Nov 6, 2018
Messages
683
Likes
580
#10
The miniDSP does have I2S headers, so it should be possible to do a DIY project that taps them and sends their output to spidf outputs, and from there to any four channel dac of your choice. The DAC on the 2 x 4 HD has a SINAD of around 90 db which would place it in the second from bottom quartile of Amir's ratings.

That project would be cheaper than buying something like an SHD Studio from miniDSP which retails for $900. And the 2 x4 HD will run FIR filters while SHD will not. Both units will also run Dirac Live 2.
 
OP
ck42
Joined
Feb 11, 2020
Messages
50
Likes
34
Location
N. Atlanta
Thread Starter #11
The miniDSP does have I2S headers, so it should be possible to do a DIY project that taps them and sends their output to spidf outputs, and from there to any four channel dac of your choice. The DAC on the 2 x 4 HD has a SINAD of around 90 db which would place it in the second from bottom quartile of Amir's ratings.

That project would be cheaper than buying something like an SHD Studio from miniDSP which retails for $900. And the 2 x4 HD will run FIR filters while SHD will not. Both units will also run Dirac Live 2.
I really like this idea!
Looking at those other threads now. From a DIY perspective, I can do this. The problem I see though with my wanting to run DSP and bi-amped speakers is, as you alluded to via the 'four channel DAC' comment, is that I'd need 4 channels of DAC in the chain to make this all work. (I want each speaker (and each DRIVER) to be able to run its own separate DSP 'corrections' / EQ / crossover). I already have a new 2 channel DAC...so I'd have to buy another...or buy a 4 channel DAC...which I didn't even know existed. :oops:

There's also the miniDSP nanoDIGI that would negate the need for soldering in the conversion modules...but for some reason, it's mini-USB interface is not used as a digital source input. :confused: The problem being that I NEED to have a USB digital input. (Guess I could just use a USB-to-SPDIF converter converter on the computer to address this issue though....but more $$$ for something decent)
[EDIT: Looks like a great solution for this for not much $ is just using a Topping D10 for USB->SPDIF)

Wondering if I should just abandon the idea of having the ability to have each speaker independently DSP'd. Too ambitious?
 
Last edited:

Alobar

Member
Forum Donor
Joined
Jan 2, 2020
Messages
24
Likes
29
Location
Alaska
#13
I really like this idea!
Looking at those other threads now. From a DIY perspective, I can do this. The problem I see though with my wanting to run DSP and bi-amped speakers is, as you alluded to via the 'four channel DAC' comment, is that I'd need 4 channels of DAC in the chain to make this all work. (I want each speaker (and each DRIVER) to be able to run its own separate DSP 'corrections' / EQ / crossover). I already have a new 2 channel DAC...so I'd have to buy another...or buy a 4 channel DAC...which I didn't even know existed. :oops:

There's also the miniDSP nanoDIGI that would negate the need for soldering in the conversion modules...but for some reason, it's mini-USB interface is not used as a digital source input. :confused: The problem being that I NEED to have a USB digital input. (Guess I could just use a USB-to-SPDIF converter converter on the computer to address this issue though....but more $$$ for something decent)

Wondering if I should just abandon the idea of having the ability to have each speaker independently DSP'd. Too ambitious?
Is it you that has a 2x4 HD minidsp? If so you already have a 4 ch DAC. If you have a biamped stereo system, yes you need a 4 ch DAC, but buying dual 2 ch dacs probably won't work right, you need another 4 ch DAC.
I'm interested in this thread because I have a active digital triamped system using a Minidsp 4X10HD and I'm looking for a upgrade path to get better performing dacs. I want the crossovers and dsp to be taking place downstream from my pc, and if the 4X10HD could, with its internal DAC bypassed, feed a digital 6 channel output to something along the lines of a Okto that could get me a good upgrade path and still use the minidsp for xovers and room treatment. This probably won't work, but it does give me a flicker of hope!
 
Last edited:
OP
ck42
Joined
Feb 11, 2020
Messages
50
Likes
34
Location
N. Atlanta
Thread Starter #14
Is it you that has a 2x4 HD minidsp? If so you already have a 4 ch DAC. If you have a biamped stereo system, yes you need a 4 ch DAC, but buying dual 2 ch dacs probably won't work right, you need another 4 ch DAC.
I'm interested in this thread because I have a active digital triamped system using a Minidsp 4X10HD and I'm looking for a upgrade path to get better performing dacs. I want the crossovers and dsp to be taking place downstream from my pc, and if the 4X10HD could feed a internal DAC bypassed digital 6 channel output to something along the lines of a Okto that could get me a good upgrade path and still use the minidsp for xovers and room treatment. This probably won't work, but it does give me a flicker of hope!
No, don't have a miniDSP HD.....yet.
Even if so, I'm not wanting to use the DAC in that unit. I really just want it for all the other capabilities it has.
Re-vamping my whole office listening system and trying to figure things out. And as usual, it starts off simple and has quickly gotten out of control. :p
 

TomB19

Active Member
Joined
Oct 13, 2019
Messages
110
Likes
79
#15
I will be watching this space closely, also. If this is somewhat easily doable, I will jump on it.

From reading the miniDSP forum, I get the impression digital out could be available on future products. That is based on nothing more than the devs being vague about digital out in response to several people asking for it.

I'd like to be able to route two channels to my sub via the built in DACs and two channels to a better quality DAC for full range (nearly) service. Since I can't do that, I just use the built in DACs for full range. Is that really so unthinkable?

I'm not so sophisticated as to find 90dB SINAD unlistenable. Sure, I will upgrade in 18 months when miniDSP, or anyone else, comes up with a DRC solution that will either allow me to use a better DAC or it will have better specs itself. When that day comes and I do upgrade, I'm confident I will not notice the difference. It will be a great opportunity to brag about a SINAD above 100dB, though. In the mean time, I'm enjoying a dramatically improved system with the miniDSP helping to tame some pretty angry room problems.
 

Alobar

Member
Forum Donor
Joined
Jan 2, 2020
Messages
24
Likes
29
Location
Alaska
#17
I will be watching this space closely, also. If this is somewhat easily doable, I will jump on it.

From reading the miniDSP forum, I get the impression digital out could be available on future products. That is based on nothing more than the devs being vague about digital out in response to several people asking for it.

I'd like to be able to route two channels to my sub via the built in DACs and two channels to a better quality DAC for full range (nearly) service. Since I can't do that, I just use the built in DACs for full range. Is that really so unthinkable?

I'm not so sophisticated as to find 90dB SINAD unlistenable. Sure, I will upgrade in 18 months when miniDSP, or anyone else, comes up with a DRC solution that will either allow me to use a better DAC or it will have better specs itself. When that day comes and I do upgrade, I'm confident I will not notice the difference. In the mean time, I'm enjoying a dramatically improved system with the miniDSP helping to tame some pretty angry room problems.
I'm pretty much in the same boat as you. Willing to invest another thousand in my system to replace the 4X10HD minidsp, even though I am not fully convinced I'll actually hear an improvement. It's that wondering what's being left on the SQ table that drives us audiophiles!
 

TomB19

Active Member
Joined
Oct 13, 2019
Messages
110
Likes
79
#18
Amen, brother. Amen.


On the other hand, a quick read through the miniDSP manual for the 2x4HD leads me to think it might not be too bad and might work the way I would hope. There are seperate I2S streams for outputs 1/2 and 3/4. I'm going to guess the 4x10HD will be an extremely similar architecture, likely with 5 x I2S output streams.

I direct you to page 17 of the 2x4HD manual.

https://www.minidsp.com/images/documents/miniDSP 2x4 HD User Manual.pdf
 
Last edited:

Worth Davis

Member
Forum Donor
Joined
Apr 8, 2019
Messages
82
Likes
109
#20
A 2x4HD?

I'd enhance their block diagram like this: (excuse my scribblins)

View attachment 51048
Nice! I own this , the Dirac version, and the SHD - they all work the same for main audio path. The xover can be used for simple sub setup or full blown driver crossovers with multiple flavors of crossover. To do more channels you need a 4x10 instead of a 2x4.
 
Top Bottom