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Old 23rd March 2013, 10:41 AM   #731
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Scratch that, It works sometimes and not others. On volume I have all pix still.
Back to same in other menus?
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Old 23rd March 2013, 11:43 AM   #732
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Quote:
Originally Posted by Speedysteve7 View Post
It doesn't matter what I set the contrast to, still have missing top of 2nd text.
It does adjust properly just always missing the top of 2nd row on mine.

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, 11:54 AM   #733
Ryssen is offline Ryssen  Sweden
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Quote:
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.
Or get a multi control so that you can program the NEC code,and use it for your other equipment to,a little more expensive though..
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Old 23rd March 2013, 02:03 PM   #734
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Here is a pic of the display line issue

Click the image to open in full size.

I tried using the basic EQ correction today. Adding some dB's here and there.

I started with the tapped horns. This is in room and with the calibrated mic at ear position.

Before

Click the image to open in full size.

After - just adding a PEQ correction at 85Hz.
Click the image to open in full size.

Then I lifted the slight drop off at 20Hz. Deep!

The RH channel needed a cut at 90Hz.

I when through doing this on all the drivers singly and as adjacent pairs. Took a little longer as have to cycle Najda off quite often to get sound.

Changing things and measuring on the fly is clunky - I have disconnect PC to Najda before the PC will play a tone from Holmimpulse through USB to my mic preamp.
2 laptops would ease that - have to get our other one in here on Holmimpulse duty I guess, or is there another way?

Applying this method across the freq range I got a pretty flat measurement on all 4 channels + passive super tweeter.

Still more to do and learn - I've not got into the stuff some of you guys are doing yet - will no doubt and look forward to it.

The main big plus is I applied some correction to the super sensitive JBL2482 and Vitavox S2 compression drivers - making in room flatter. I can detect no degradation in SQ

Last edited by Speedysteve7; 23rd March 2013 at 02:07 PM.
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Old 23rd March 2013, 05:44 PM   #735
paalj is offline paalj  Norway
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I ordered a couple of these:

#2806 Aluminum Preamplifier enclosure /DAC case/ amplifier chassis AMP BOX | eBay

I might be hard to fit a power... We'll see how it will fit

best,
Paal
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Old 23rd March 2013, 06:20 PM   #736
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Quote:
Originally Posted by paalj View Post
I ordered a couple of these:

#2806 Aluminum Preamplifier enclosure /DAC case/ amplifier chassis AMP BOX | eBay

I might be hard to fit a power... We'll see how it will fit

best,
Paal
Look nice. I think I may need wider to fit the expansion board into though. They do a bigger one - price goes up though...

Just EQ'd a load more with 2 laptops - nice and easy

Here's the LH channel all 5 drivers, in room mic at ear position

Click the image to open in full size.

RH

Click the image to open in full size.

Both L & R

Click the image to open in full size.

The usual +/-5dB in room is good is sorted!

Listening it all sound well controlled and nothing lacking right across the rev range. More listening to be done.
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Old 23rd March 2013, 10:59 PM   #737
chaparK is offline chaparK  Luxembourg
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About contrast to max:
Quote:
Originally Posted by Shaun View Post
Yes.
When contrast is set to max (full bar displayed), then the PWM duty cycle is near to 0. We have reached the contrast limit of the display.
You can check this by connecting your scope on pin 3 of the LCD header and change contrast in the menu.
Basically I cannot increase the display's contrast any further. I've added 2 more settings but they're at the lower end.

Quote:
Originally Posted by paalj View Post
Hi Nick,
Great!
Yeah, and a filterbank with assignable taps so they don't get lost
You mean more flexibility with tap numbers vs. channels right?

Quote:
Regarding LCD I use only half contrast.
Cool, one normal LCD display out there

Quote:
Originally Posted by paalj View Post
I ordered a couple of these:

#2806 Aluminum Preamplifier enclosure /DAC case/ amplifier chassis AMP BOX | eBay

I might be hard to fit a power... We'll see how it will fit
Yup, as Steve said, they're a bit narrow. Internal width is 260 mm and Najda is 230 mm.
This one from the same supplier would suit better if you want to fit also the power supply in:
S-3207 Aluminum amplifier case / Enclosure /amplifier BOX/ PSU Case | eBay

Maybe you can even flip the rear panel to have the power socket cut on the left side

Quote:
Originally Posted by Speedysteve7 View Post
Look nice. I think I may need wider to fit the expansion board into though. They do a bigger one - price goes up though...

Just EQ'd a load more with 2 laptops - nice and easy

Here's the LH channel all 5 drivers, in room mic at ear position

Click the image to open in full size.

RH

Click the image to open in full size.

Both L & R

Click the image to open in full size.

The usual +/-5dB in room is good is sorted!

Listening it all sound well controlled and nothing lacking right across the rev range. More listening to be done.
Looks good Steve, thanks for sharing. How many EQs?



Today I looked at this idea that Kazam talked about and I tried to put it together with Shaun's comments.

So here's what the Board Configuration dialogue could look like.

If you want to set a global level, all the sliders are disabled and the level is rated in Vrms:

BoardConfig1.png

If you'd like to set various analogue gains for the outputs, then the combobox is disabled and the gains are rated in dB:

BoardConfig2.png

This might be part of the forthcoming soft/firm revision.

Best,

Nick
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Old 24th March 2013, 07:19 AM   #738
paalj is offline paalj  Norway
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Quote:
Originally Posted by chaparK View Post

You mean more flexibility with tap numbers vs. channels right?

Yup, as Steve said, they're a bit narrow. Internal width is 260 mm and Najda is 230 mm.
This one from the same supplier would suit better if you want to fit also the power supply in:
S-3207 Aluminum amplifier case / Enclosure /amplifier BOX/ PSU Case | eBay

Maybe you can even flip the rear panel to have the power socket cut on the left side

Today I looked at this idea that Kazam talked about and I tried to put it together with Shaun's comments.

So here's what the Board Configuration dialogue could look like.

If you want to set a global level, all the sliders are disabled and the level is rated in Vrms:


If you'd like to set various analogue gains for the outputs, then the combobox is disabled and the gains are rated in dB:

This might be part of the forthcoming soft/firm revision.

Best,

Nick
Hi Nick,
Yes, more flexibility. With a 2-way I am not able to use more than about 3000 taps of 9000? available.

I didn't see the wider one OK I have to live with that now.

Great news on gain structure optimizing. I had to attenuate my tweeter digitally with 11dB. Now I can do that on the output. How would the output graphs look like then? Would you include the analog attenuation?

best,
Paal
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Old 24th March 2013, 11:40 AM   #739
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Looks good Steve, thanks for sharing. How many EQs?

>> 2 or 3 on each output. Processor at 57%. Have 4 X/O, delays on 6 outputs and the correction.

This might be part of the forthcoming soft/firm revision

>> That would be cool.

I'll see if I am up for the display swap today F1 first though
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Old 25th March 2013, 08:24 PM   #740
chaparK is offline chaparK  Luxembourg
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Quote:
Originally Posted by paalj View Post
Yes, more flexibility.
OK I'll do that.

Quote:
Great news on gain structure optimizing. I had to attenuate my tweeter digitally with 11dB. Now I can do that on the output. How would the output graphs look like then? Would you include the analog attenuation?
Well, no. The graph shows the Setup file expected outcome, meanwhile the output level is a board setting. A Setup file is a collection of DSP parameters, so analogue gains won't show up in the graph.

It's not always clear what should be seen in this graph and what should not be included.

For example, you had this FIR LR approximation with one 511-tap LF and one 255-tap HF.
We found out that it's better to take the delay into account when computing the phase otherwise the Electrical Sum looks ugly.
So I changed this and now the Sum of your FIR looks beautiful, that's great.

But that will maybe introduce problems for other users who keep to IIR filters because they use delays for another purpose. So, if you design a IIR LR4 crossover, you expect that the bands sum flat, right? But if you have added delay on one channel, then it's not going to sum flat anymore.

The above is right because we make an electrical sum. It's like if you were taking the output channels and summing them in the analogue domain - meanwhile when you add delay in a IIR setup, you do that in order to time-align your drivers.

(Anyway, that's a long talk I've been having with myself and it's not really clear to me )

Quote:
Originally Posted by Speedysteve7 View Post
Looks good Steve, thanks for sharing. How many EQs?

>> 2 or 3 on each output. Processor at 57%. Have 4 X/O, delays on 6 outputs and the correction.
That sounds good. You're more than safe re. CPU. A quick computation shows that if both DSPs are at 57%, then you still have enough resources for over 70 EQs (at 96 kHz).

Quote:
This might be part of the forthcoming soft/firm revision

>> That would be cool.
OK that's in now, all tested and seems OK. I'll throw in a few more things and we'll make the release that will include a fix for this annoying bug that you have.

Quote:
I'll see if I am up for the display swap today F1 first though
So how did it go?

(JCGA has a great LCD: DSP Xover project (part 2))
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