• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required. There are many reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

MiniDSP DDRC-22D DIRAC measurements

Olli

Senior Member
Forum Donor
Joined
Mar 6, 2018
Messages
331
Likes
242
I have one for sale in Germay in case someone is interested.
 

guyinoz

Member
Forum Donor
Joined
Aug 30, 2019
Messages
20
Likes
9
The reduction is there to make room for some frequency boost.
So you can't expect to "correct" it in the DAC, since you'd probably overload it with corrected signal.
Thanks so much for the reply. So is there a downstream impact on amplifier? Say it has 29 dB gain so does it become 19 dB gain , everything else remaining the same?
 
OP
R

Rja4000

Major Contributor
Forum Donor
Joined
May 31, 2019
Messages
2,681
Likes
4,219
Location
Liège, Belgium
Thanks so much for the reply. So is there a downstream impact on amplifier? Say it has 29 dB gain so does it become 19 dB gain , everything else remaining the same?
The gain will remain the same.
But the source signal, on average, will be 10dB less.
And the same is true for the output, of course.

But is that a problem?
You will, most probably, listen to music with some attenuation ("volume" setting lower than maximum).
If you want average level to remain the same, you may just attenuate by 10dB less (push volume setting 10dB up).
If you're not already listening louder than 10dB below maximum level, of course.
 
Last edited:

o2so

Active Member
Forum Donor
Joined
Sep 9, 2019
Messages
250
Likes
143
Location
Sydney, Australia
The reduction is there to make room for some frequency boost.
So you can't expect to "correct" it in the DAC, since you'd probably overload it with corrected signal.
Hi and thanks for the write up.
I an thinking of using the Minidsp unit's volume control as main volume control for my system. If possible I'd like to have an understanding of the extent to which this may reduce SNR and overall performance vs using a good analogue volume pot.

Many thanks!
 

o2so

Active Member
Forum Donor
Joined
Sep 9, 2019
Messages
250
Likes
143
Location
Sydney, Australia
This is purely digital path here.
The same RME SINAD is around 113dB (around 0dBFS) when looped back with analog conversion (DAC->ADC), and this is pretty impressive.
But here, it's just used as an USB/AES converter... which is why the figures are much higher in 'no correction' mode.

So the limit, in real life situation, will be the digital to analog conversion (whatever the DAC, at around -10dBFS 1kHz) , not the DSP.
The 25dB SNR decrease is in digital domain, but digital noise level is still very low after that, so the final analog-level noise will still be mainly set by the conversion, IMO.

Said differently: the correction "consumed" 4 of the 24 bits, but current DACs can only reproduce 20 bits, so that's not an issue.

This is, basically, what I wanted to check.
Doesn't the Minidsp ddrc 22d work with 32bits internally? At least this is what the specs suggest.
 
OP
R

Rja4000

Major Contributor
Forum Donor
Joined
May 31, 2019
Messages
2,681
Likes
4,219
Location
Liège, Belgium
OP
R

Rja4000

Major Contributor
Forum Donor
Joined
May 31, 2019
Messages
2,681
Likes
4,219
Location
Liège, Belgium
Doesn't the Minidsp ddrc 22d work with 32bits internally? At least this is what the specs suggest.
I guess it does.
My 'bits' analogy was to explain that, even if the internal DSP treatment degrades the signal, we have enough left that the main degradation still comes from the DAC (and the rest of the reproduction chain, of course).
 

guyinoz

Member
Forum Donor
Joined
Aug 30, 2019
Messages
20
Likes
9
Hi, i have bought the DDRC-24 along with a UMIK-1 and done the Dirac measurements along with integrating a sub woofer through the cross over functionality of the minidsp plug-in. So far i have been happy and the process was relatively easy, although one does have to print out the DDRC-24 manual and the Dirac 2.0 addendum to do the process end to end. I am still figuring out how all the options in the minidsp plugin and the multiple sets of filters in the Dirac 2.0 software work together.
 

Willem

Major Contributor
Joined
Jan 8, 2019
Messages
3,654
Likes
5,276
I am wondering how this compares to the a third more expensive MiniDSP SHD Studio.
 
OP
R

Rja4000

Major Contributor
Forum Donor
Joined
May 31, 2019
Messages
2,681
Likes
4,219
Location
Liège, Belgium
I am wondering how this compares to the a third more expensive MiniDSP SHD Studio.
As far as Dirac processing is involved, I guess result would be very similar.
That's probably the same DSP anyway.
Note that mine is with older DIRAC version though.
So there may be a difference there.
 

AndrewDavis

Active Member
Joined
Apr 4, 2019
Messages
220
Likes
431
I am wondering how this compares to the a third more expensive MiniDSP SHD Studio.

The SHD has the capability to run Volumio and stream music, "bi directional" music playback (which I'm sure is useful in a studio application) and more I/O. Based on the specs, it looks as if the tech powering DIRAC in both is the same.

Yes, I'm aware I'm reviving an old thread but I just ordered a DDRC-22D and I'm going to need a place share. So I'll be back!
 

Trevor

Member
Joined
Nov 28, 2020
Messages
14
Likes
0
The SHD has the capability to run Volumio and stream music, "bi directional" music playback (which I'm sure is useful in a studio application) and more I/O. Based on the specs, it looks as if the tech powering DIRAC in both is the same.

Yes, I'm aware I'm reviving an old thread but I just ordered a DDRC-22D and I'm going to need a place share. So I'll be back!

Hi! Any recent thoughts about DDRC-22D? Thank you..
 
Top Bottom