Any measurements on the MiniDSP - diyAudio
Go Back   Home > Forums > Commercial Sector > Manufacturers > miniDSP

miniDSP Low cost, modular Digital Signal Processor (DSP) kits for the DIYer from miniDSP.

Reply
 
Thread Tools Search this Thread
Old 22nd October 2010, 12:35 AM   #1
doug20 is offline doug20  United States
diyAudio Member
 
Join Date: Mar 2009
Default Any measurements on the MiniDSP

has anyone did the measurements on the MiniDSP? Something like a simple loop back test like we do with sound cards when using measurement tools like HOLM.

I would love to see some. I curious about the MiniDSP performance overall and also what it does under 20Hz. I can use it as a SSF (Shelf filter and boost) but I need to know its measurements first.
  Reply With Quote
Old 22nd October 2010, 02:23 AM   #2
Davey is online now Davey  United States
diyAudio Member
 
Join Date: Dec 2001
Location: Bremerton, WA.
Doug,

I'm not sure what the question really is. Your question implies there is some sort of inherent frequency response limitation in the MiniDSP that would need to be understood and accounted for. It doesn't work that way.
You can assume the measured output will look exactly like the displayed curve in the MiniDSP software application.....Unless you force it into clipping with too much programmed boost or too much input voltage.

The specified 900mV output voltage limitation is accurate. I see the onset of clipping at about 905mV on my units.

The low frequency response is essentially flat to well below 20Hz. The output capacitor is a large value and should yield a near-DC turnover point with any nominal load.

Anyways, I've done quite a few measurements on mine. What do you want to see? I can program something specific if you'd like.

Cheers,

Dave.
  Reply With Quote
Old 22nd October 2010, 11:37 AM   #3
doug20 is offline doug20  United States
diyAudio Member
 
Join Date: Mar 2009
I just want to see the real response curve. All products have a inherent frequency response limitation and they all have noise floors to say the miniDSP does not work that way does not make sense since processors, Amps, DCX, Art cleanbox, SMS-1. eD EQ.2 (All products I have owned) and so on all have been measured to show the noise levels and overall response curve. Many have inherent Subsonic Filters, The Art Cleanbox rolls of serverly at 18Hz, the old version of the SMS-1 also rolled off early below 20Hz, I know of several amps and processors that have issues below 20Hz.

"well below 20Hz" is not meaningful enough when my two different sub systems (1 IB array and one multi-sealed disign) go into single digits. I want to know if the MiniDSP can be used as a manual EQ for high end sub systems that have no limits.

EDIT: I see you do comment that its near DC so that is great.

Any measurements you have done would be awesome. Im not the only one interested in seeing pretty graphs

btw, your help on all this is very much appreciated!

Last edited by doug20; 22nd October 2010 at 11:46 AM.
  Reply With Quote
Old 22nd October 2010, 02:52 PM   #4
Davey is online now Davey  United States
diyAudio Member
 
Join Date: Dec 2001
Location: Bremerton, WA.
Doug,

Well, what I was trying to say (not very well I guess) is that you can consider the MiniDSP response flat....for all intents and purposes.

Anyways, here's a frequency response measurement on one of my MiniDSP units with no crossover/EQ/delay/etc programmed.....into a 10k ohm load.
(Mine is a Rev. B board which explains the -7.9db offset.)

Noise floor (yellow) with a few other measurements as references. Stock DCX2496 outputs (red), line outputs from EMU Tracker-Pre (violet), noise floor of my measuring system (aqua.)

Hope that helps.

Cheers,

Dave.
Attached Images
File Type: png miniresp.png (138.5 KB, 1528 views)
File Type: jpg minirflr.jpg (198.8 KB, 1447 views)
  Reply With Quote
Old 22nd October 2010, 05:14 PM   #5
doug20 is offline doug20  United States
diyAudio Member
 
Join Date: Mar 2009
Thank you for the measurements. Awesome comparisons.

Last edited by doug20; 22nd October 2010 at 05:17 PM.
  Reply With Quote
Old 22nd October 2010, 07:00 PM   #6
pos is offline pos  Europe
diyAudio Member
 
pos's Avatar
 
Join Date: Feb 2008
Location: Paris
I did not expect such good measurements, given that the DCX is specified for a 119dB dynamic range (analogue in and out) whereas the minidsp in only ">98dB".

That is quite impressive indeed! Is it done with analogue inputs and outputs?
  Reply With Quote
Old 22nd October 2010, 08:26 PM   #7
Davey is online now Davey  United States
diyAudio Member
 
Join Date: Dec 2001
Location: Bremerton, WA.
Well, you have to remember the DCX can spit out signal levels quite a bit higher than the MiniDSP. The majority of folks utilize the DCX2496 improperly, which is why there's such a variation of opinion on its performance.

Anyways, with any DSP devices of this type, gain structure has to be well understood and considered to achieve the best performance. Analog circuits don't (generally) have this limitation.

The MiniDSP has terrific test bench performance and the maximum signal levels are well considered (IMHO) to allow the units to be integrated successfully into a wide variety of systems.

Cheers,

Dave.
  Reply With Quote
Old 22nd October 2010, 08:48 PM   #8
pos is offline pos  Europe
diyAudio Member
 
pos's Avatar
 
Join Date: Feb 2008
Location: Paris
Would you have measurements at full output? Lets say using the digital input for both the DCX and the minidsp, and feeding them with a 0dB digital signal?
That is the way I use my DCX (with an SPL volume8 analog control), so that is how I would also use the minidsp (and specifically the balanced version)

Would you also happen to have distortion and maybe jitter measurements?
  Reply With Quote
Old 1st November 2010, 10:39 AM   #9
theresa is offline theresa  United States
diyAudio Member
 
Join Date: Aug 2009
Default Turn down input or output?

Do I need to turn down the input and/or output level to avoid overloading? I'm using them with a Emotiva processor and amps. I don't want to set up for measuring it at the moment as I am just putting together a new system.
  Reply With Quote
Old 2nd November 2010, 05:35 PM   #10
Davey is online now Davey  United States
diyAudio Member
 
Join Date: Dec 2001
Location: Bremerton, WA.
Quote:
Originally Posted by theresa View Post
Do I need to turn down the input and/or output level to avoid overloading? I'm using them with a Emotiva processor and amps.
Probably not. The inputs/outputs of the MiniDSP modules are limited to 900mV, and that's right in the neighborhood of where most amplifiers would be delivering their rated power. So, if your MiniDSP modules are feeding the amplifiers directly I'd say your chances of clipping the MiniDSP outputs are near zero. This is what I was referring to with the "well considered maximum levels" comment. Unlike the DCX (and other commercial units) a multi-channel post-volume control is not necessary with the MiniDSP units.

The Emotiva power-amps have 32db voltage gain (which is a bit more than usual) so your MiniDSP working voltage levels would be a bit less than they would otherwise and reduce the chances of clipping even further.

Obviously, if programming large EQ boosts in the MiniDSP you might get into trouble, so you have to be aware.

Cheers,

Dave.
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
miniDSP introduction, what we do, who we are minidsp miniDSP 53 30th October 2011 01:48 PM
miniDSP New Plug-ins minidsp miniDSP 5 31st January 2011 02:08 PM
miniDSP in a BOX otto88 miniDSP 3 21st October 2010 07:53 PM
miniDSP 2x4, a new home for miniDSP minidsp miniDSP 8 27th August 2010 01:11 AM
My MiniDSP setup Kjeldsen Digital Line Level 37 5th August 2010 09:39 AM


New To Site? Need Help?

All times are GMT. The time now is 02:47 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright ©1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2