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Old 22nd March 2013, 04:54 PM   #721
Shaun is offline Shaun  South Africa
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Mine is set to max. While it was on the table I had it set for viewing from directly in front (level with the front panel). Now I look mostly from an elevated position.
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Old 22nd March 2013, 09:48 PM   #722
chaparK is offline chaparK  Luxembourg
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Quote:
Originally Posted by Shaun View Post
Mine is set to max. While it was on the table I had it set for viewing from directly in front (level with the front panel). Now I look mostly from an elevated position.
Shaun, when you say 'max', you mean full bar displayed in the contrast menu, is that right?

How about you Steve? James? Have you also set contrast as Shaun above?

One thing you could try is a capacitor between pin 1 and 3 of the LCD module. Any moderate value should be alright, for example 10 uF. This will convert the PWM into a flat output of varying level - in case your LCD module doesn't like the PWM.
(if you use a polarized cap, then + is on pin 3)
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Old 22nd March 2013, 10:33 PM   #723
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Strangely, just as I was about to pack it up to return it - the display returned to normal. Hmmmm. Its been ok for a few hours now.

However, I have another fault! The remote behaves very weirdly. Sometimes, maybe 1 in 3, the volume control swaps over and UP makes it quieter. and DOWN, louder. I think it is just continuing to adjust in the direction it was previously going. It rights itself with a few presses. OK, it could be my remote (which works fine on the machine that it came from). Unfortunately, I had a household remote purge a few months ago so I don't have another one to try. I'll try to find one soon. But my hunch is that its Nadja playing up...?


Re the LCD. I have my contrast set to maximum. I'll try the cap at some point soon. Actually I was thinking about the display. Eventually what I'd really like is a BIG display for volume. Maybe a line or circle of leds (something artistic?) - its nice to see something from a distance even if its not the actual attenuation. Failing that, a LED for 'remote command received' would be good. Is that possible somehow?

Another question. I have an setup at the moment with 7 filters in total and a bit of delay. Its at 192k. The DSPs are both well over 90%. Is that correct? I'm slightly worried that when I get it all set up with more channels and more delay I could run out...

cheers,
james
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Old 22nd March 2013, 11:24 PM   #724
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ChaparK,

Another request!

I have an unusual horn system. The low-midbass 50-140ish is a huge 5 metre 40hz horn in the roof. But this is mono. So, I have 2 direct radiators which are stereo. I'd like to supply them with the difference between the mono and stereo signal. i.e. LEFT is L-R and RIGHT is R-L. I appreciate that I might be the only person in the world who wants this... but isn't it just 5 minutes of coding? Thanks!

james

Last edited by maravedis; 22nd March 2013 at 11:34 PM.
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Old 22nd March 2013, 11:36 PM   #725
chaparK is offline chaparK  Luxembourg
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Quote:
Originally Posted by maravedis View Post
Strangely, just as I was about to pack it up to return it - the display returned to normal. Hmmmm. Its been ok for a few hours now.
Aha That's good to hear, thanks for letting me know.

Quote:
However, I have another fault! The remote behaves very weirdly. Sometimes, maybe 1 in 3, the volume control swaps over and UP makes it quieter. and DOWN, louder. I think it is just continuing to adjust in the direction it was previously going. It rights itself with a few presses. OK, it could be my remote (which works fine on the machine that it came from). Unfortunately, I had a household remote purge a few months ago so I don't have another one to try. I'll try to find one soon. But my hunch is that its Nadja playing up...?
Hmm. So Najda implements the NEC protocol as documented in the literature. We could of course look with the scope at the pulses out of the IR sensor when you press a key on your remote and see whether it's really a NEC - but I suppose it's easier to get just another remote. There are small remotes on ebay for a few bucks - I've tested a couple and they're OK.

Quote:
Re the LCD. I have my contrast set to maximum. I'll try the cap at some point soon. Actually I was thinking about the display. Eventually what I'd really like is a BIG display for volume. Maybe a line or circle of leds (something artistic?) - its nice to see something from a distance even if its not the actual attenuation.
Well this is going to be a lot of work as display data is now coded for HD44780 controllers on a 8-bit parallel bus... How about getting a larger LCD display? I think that the ones with white characters on black background have great contrast.

Quote:
Failing that, a LED for 'remote command received' would be good. Is that possible somehow?
Unfortunately all leds are now in use - I've already implemented the CPU overload warning led we were discussing a few posts back in this thread.

Quote:
Another question. I have an setup at the moment with 7 filters in total and a bit of delay. Its at 192k. The DSPs are both well over 90%. Is that correct? I'm slightly worried that when I get it all set up with more channels and more delay I could run out...
192 kHz is CPU hungry twice as much as 96 kHz and 4 times as much as 48 kHz.

When you load an 'empty' preset, it's actually not empty because the DSPs are managing 4 inputs and 10 outputs. That's 14 delay lines, 24 gains plus the routing section.
Adding delay will not increase the CPU load. Delay lines are already included in the 'empty' presets.

Biquads are implemented in full double precision, i.e. on the feedforward path as well as on the feedback path. This is especially important with higher sampling rates as simple precision coefficients get quickly ill conditioned as you lower the frequency of your filters.

What I could do is allow disabling some channels, so that if you use less than 10 output channels you can turn off the unused channels and recover some CPU for additional filters on the channels effectively in use.

If you have a setup with lots of filters, I recommend that you lower the sampling frequency down to 96 kHz. You can also send me your setup files on my email and I'll see if there's a way to rearrange your filters and achieve better efficiency.

Best,

Nick
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Old 22nd March 2013, 11:40 PM   #726
chaparK is offline chaparK  Luxembourg
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Quote:
Originally Posted by maravedis View Post
ChaparK,

Another request!

I have an unusual horn system. The low-midbass 50-140ish is a huge 5 metre 40hz horn in the roof. But this is mono. So, I have 2 direct radiators which are stereo. I'd like to supply them with the difference between the mono and stereo signal. i.e. LEFT is L-R and RIGHT is R-L. I appreciate that I might be the only person in the world who wants this... but isn't it just 5 minutes of coding? Thanks!

james
You can already do that. In the Input section, DIFF is defined as (Left-Right)/2.
Select the routing accordingly in the Channel Processing tab.
If you want (Right-Left)/2, you just need to invert channel polarity.

This one was easy Enjoy!
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Old 23rd March 2013, 04:29 AM   #727
Shaun is offline Shaun  South Africa
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Quote:
Originally Posted by chaparK View Post
Shaun, when you say 'max', you mean full bar displayed in the contrast menu, is that right?
Yes.
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Old 23rd March 2013, 07:19 AM   #728
paalj is offline paalj  Norway
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Quote:
Originally Posted by chaparK View Post

What I could do is allow disabling some channels, so that if you use less than 10 output channels you can turn off the unused channels and recover some CPU for additional filters on the channels effectively in use.

Best,

Nick
Hi Nick,
Great!
Yeah, and a filterbank with assignable taps so they don't get lost

Regarding LCD I use only half contrast.

I also tested a remote that suddenly adjusted the volume up instead of down. I changed the direction on my hand and it worked normal, but I changed to anoter remote that worked ok.

best,
Paal
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Old 23rd March 2013, 10:14 AM   #729
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It doesn't matter what I set the contrast to, still have missing top of 2nd text.

I am using the JVC protocol on remote.
Works on both One for all remotes I have.
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Old 23rd March 2013, 10:31 AM   #730
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I just clipped a 10uF on display pins 1 & 3.
Does indeed bring that dim top line
to darker.
I used massive passive x/o cap which seemed
to take a while to work... Need to find a smaller elecrolytic I guess.

Last edited by Speedysteve7; 23rd March 2013 at 10:42 AM.
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