Need Help 2x4 Balanced very very low output - 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 23rd January 2015, 01:28 PM   #1
almat is offline almat  France
diyAudio Member
 
Join Date: Nov 2008
Default Need Help 2x4 Balanced very very low output

Hi everybody,

I received yesterday a pair of 2x4 balanced and a pair of miniDIGI to stack on.

The output level, on both boards, is very very very low, some mV despite the high level output seen on the monitor.
Same thing on analog and digital input.
-3dB output level gives 10mV.

Any clue ?

TIA
Alain
Attached Images
File Type: jpg Levels.jpg (49.2 KB, 69 views)
  Reply With Quote
Old 23rd January 2015, 03:11 PM   #2
diyAudio Member
 
Join Date: Mar 2007
Location: California
Do you have the volume control enabled but don't have a potentiometer connected? That can cause this exact problem. Read your documentation again.
__________________
"Hardware eventually fails. Software eventually works" - Michael Hartung
  Reply With Quote
Old 23rd January 2015, 04:25 PM   #3
almat is offline almat  France
diyAudio Member
 
Join Date: Nov 2008
Hello Charlie,

Thanks for the fast reply

No pot and not Enabled

When I received the boards I first checked it.
Plugged it into a Meanwell 12V power supply.

On one of the boards the little tiny blue LED was not flashing at all, tried the reset button, unplugged, plugged ...
Imho the board is out, I can connect to but for example a +16dB EQ gives a measured +3,5dB at the output ...

Tried the other one with and without the miniDIGI, Analog and I2S Input, same thing, a very low output, typically 10mV for a -3dB monitor.

I have a 2x8 and had some 2x4 nothing to compare.

Alain

A view of the boards while checking

Click the image to open in full size.
  Reply With Quote
Old 23rd January 2015, 05:10 PM   #4
diyAudio Member
 
Join Date: Mar 2007
Location: California
What master/slave jumper settings are you using on each board. I use a pair of miniDIGI + 2x4 balanced in some active speakers I built but it took me a long time to figure out the jumper settings. The manuals are totally confusing, and even the miniDSP forum and emails to the techs was no help. I'm fed up with miniDSP after that frustrating episode.

If you look in the Hardware forum on the miniDSP web site, you will see many posts about people having problems getting this pair of products working. There is a long thread from me sometime last year, but more recently. I would not bother posting there, as you have to wait one or two weeks for a reply if you are lucky enough to get one at all.

Anyway, I set both jumpers to "slave" and that seems to work for me.

It's certainly possible that one of your board is dead...
__________________
"Hardware eventually fails. Software eventually works" - Michael Hartung
  Reply With Quote
Old 23rd January 2015, 05:31 PM   #5
almat is offline almat  France
diyAudio Member
 
Join Date: Nov 2008
Hi Charlie,

I think the jumpers affair is "clearly" fixed, not explained, in the Jumper chart - 4way configuration :
https://www.minidsp.com/images/docum...figuration.pdf

Jumpers are set to Slave on both miniDSP and minDIGI.
That's the way I use it.

It's certainly possible that one of your board is dead...
I am pretty sure indeed

Alain
  Reply With Quote
Old 24th January 2015, 06:32 PM   #6
Davey is offline Davey  United States
diyAudio Member
 
Join Date: Dec 2001
Location: Bremerton, WA.
Quote:
Originally Posted by CharlieLaub View Post
Do you have the volume control enabled but don't have a potentiometer connected? That can cause this exact problem. Read your documentation again.
Actually, no. If the volume control is enabled in software and you have an attached control at CCW or a disconnected control, the output channel indicators will drop to reflect the actual (low) output voltage.

Alain,

Are you sure you don't have a connection issue on the outputs? If using an unbalanced interface, you would utilize the "S" and "+" outputs. Is that how you're configured??

Dave.
__________________
"Where's the Caddy?" "I traded it for a microphone." "Okay, I can see that."
  Reply With Quote
Old 24th January 2015, 08:01 PM   #7
almat is offline almat  France
diyAudio Member
 
Join Date: Nov 2008
Hi Davey,

Quote:
Originally Posted by Davey View Post
Alain,
Are you sure you don't have a connection issue on the outputs? If using an unbalanced interface, you would utilize the "S" and "+" outputs. Is that how you're configured??
Dave.
Absolutely.
S and - wired, unbalanced signal between S- and +, inputs and outputs
And I also measured S+ and S- of each of the four outputs without any wire

Did it with I2S input too.

I try again 5 minutes before this reply, analog and I2S inputs, same result.

It's very strange that the both boards act as the same.
I am pretty sure that the "unflashing led" board is out, so it should lead to non operational outputs, but the other one is quite a mystery.

My 2x8 is working nicely on balanced outputs.
Attached Images
File Type: jpg Balanced.jpg (105.1 KB, 49 views)
  Reply With Quote
Old 27th January 2015, 12:30 AM   #8
Davey is offline Davey  United States
diyAudio Member
 
Join Date: Dec 2001
Location: Bremerton, WA.
Just for grins, I would try removing the S/- jumper, and make your connection just to the S/+ connections. There's no reason for that jumper on the output connectors.....only the inputs.

Dave.
__________________
"Where's the Caddy?" "I traded it for a microphone." "Okay, I can see that."
  Reply With Quote
Old 27th January 2015, 09:02 AM   #9
almat is offline almat  France
diyAudio Member
 
Join Date: Nov 2008
Hi Dave,

Thanks for replying.

As I previously told I have also measured all the S+ and S- without any wire on
Same result.


I think I'll buy a 2x4 in a box at my French reseller site to compare with these boards.
  Reply With Quote
Old 27th January 2015, 09:09 PM   #10
Davey is offline Davey  United States
diyAudio Member
 
Join Date: Dec 2001
Location: Bremerton, WA.
Sorry, yep you did mention measuring individual connections.

Still very puzzling that you would have two boards fail in (seemingly) the same way.
Since the output indicators in your plugin indicate a good signal, it would seem the issue is external to the DSP chip and located somewhere in the analog output circuitry.

Dave.
__________________
"Where's the Caddy?" "I traded it for a microphone." "Okay, I can see that."
  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 2x4 low gain problem Freecrowder Digital Line Level 5 4th September 2014 03:44 PM
2x4 output impedance, DC filter help? SunShade miniDSP 1 29th January 2014 04:47 AM
Mini dsp 2x4 output buffer Beau miniDSP 9 28th April 2013 03:00 AM
Question on Balanced minidsp 2x4 quinnling miniDSP 2 11th December 2012 12:53 PM
Have a balanced 2x4... where to go from here RockLeeEV miniDSP 7 22nd September 2012 07:10 PM


New To Site? Need Help?

All times are GMT. The time now is 03:53 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2015 DragonByte Technologies Ltd.
Copyright 1999-2015 diyAudio

Content Relevant URLs by vBSEO 3.3.2