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5.1 channel preamp
5.1 channel preamp
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Old 12th November 2019, 03:10 AM   #21
stratus46 is offline stratus46  United States
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Join Date: Nov 2009
Location: Los Angeles
I double checked this to be certain. The SW output is always low passed regardless of the
switch position.

The cheapest units with the momentary buttons default to 5.1. When feeding it plain 2 channel
stereo it will pass L and R at reduced level to the surround channels which my wife did not
like. The unit I ended up with has a slide switch, in my case a 3 position, PASS, 2CH, 5.1.
Normal for here is PASS which sends only the channels in the stream. L & R only for stereo and
5.1 when present. In all cases whenever the sub channel has signal it is always LP filtered.

My Polk powered sub has its own adjustable LPF so even if sent full bandwidth will knock
it down to lows only.

Your TPA amps have a LOT more power than mine but mine is still more than sufficient.

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Old 12th November 2019, 05:10 AM   #22
jimk04 is online now jimk04  United Kingdom
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Join Date: Jul 2018
Location: North Notts
Thankyou again. I guess we dont know what frequency the SW is filtered? I am not asking you to look into this, just wandered if you knew?

I have a Polk active sub too but the cable that feeds it is a single RCA that connects to the LFE single socket on the sub. As far as I am aware it needs to be an LF signal. There are filter controls on the SW panel also but I believe this is if feeding it a speaker level signal or using the stereo RCA inputs. I looked at the manual again yesterday to check.
My single RCA cable from my present AVR to SW is buried under the carpet. Hence me being a bit in a corner with how I feed it.
Thanks for your help again
For the cost of these and the present 11.11 offers on Aliexpress I may just try one
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Old 28th November 2019, 03:44 AM   #23
stratus46 is offline stratus46  United States
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Location: Los Angeles
I found what I consider to be a serious bug in the 5.1 software for the Arduino. In single channel volume
mode the MUTE button went to MAX volume rather than MIN. I'm sure nobody is using it besides me but
I wanted to add the corrected version before I forget.

Attached Files
File Type: txt LG_remote51T9.txt (32.3 KB, 12 views)
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Old 11th December 2019, 04:33 PM   #24
os77 is offline os77
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Join Date: Dec 2010
Location: France - Gujan-Mestras
Hello, I wish to send a big thanks to Stratus46.
Who have demonstrated that it is (relatively) easy to make myself a volume-control system with an Arduino board and its software to drive PGA2310.
I tried to recover all of your lines of code, but I failed. My brain is not big enough

So I took inspiration from them to make my complete application.
My specifications are much simple than yours, control volume is the same, just behind an active crossover, without any tone control.
So I started in the realization of the software.
The "online" support (Coder, IR remote, display, EEPROM etc...) for the Arduino IDE is really effective and helps me a lot.
Firstly I bought 14 segment displays (like yours, blue aren't disponibles
in France... White only ...) an arduino UNO board to build the software.
I will replace 14 segments AdaFruits with LCD 2 lines of 16 characters.
Now, only the prototype of this new display is created.
I still have to integrate it into the existing code. A unique C function is created.
Then, I have to create the software that controls 2 outputs trigger:
1 output to control the power up processor, and
1 output to control power up amplifiers.

I wanted to thank you for your approach because:
It is more than 4 years that I seek,(Without success, or very incomplete solution) an "intelligent" solution to replace the CHINESE KIT, whose software is very poor.
I attach some photos of the prototype board, and also photos of the new display. It's more pleasant, according to me.
When the 16x2 display and the triggers are integrated I will attach the code in this site, perhaps it may be useful to someone ?
NB: spécifications are also join to this post, in french unfortunely, but synoptics are explicits
Attached Images
File Type: jpg Volume Display.jpg (313.7 KB, 156 views)
File Type: jpg BALANCE_CENTERED_Display.jpg (222.3 KB, 164 views)
File Type: jpg Offset_Adjust_Chanel 1.jpg (246.4 KB, 153 views)
File Type: jpg Minimal_Gain_Adjust.jpg (236.5 KB, 158 views)
File Type: jpg Maximal_Gain_Adjust.jpg (207.4 KB, 160 views)
File Type: jpg Mute_minus_12dB_Display.jpg (243.3 KB, 26 views)
File Type: jpg Mute_100%_Adjust.jpg (242.8 KB, 26 views)
File Type: jpg New_16x02_lines_Volume_Display.jpg (165.7 KB, 46 views)
File Type: jpg New_16x02_lines_Balance_Display.jpg (142.3 KB, 46 views)
Attached Files
File Type: pdf Projet PGA2310.pdf (295.1 KB, 20 views)
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Old 13th December 2019, 05:33 AM   #25
stratus46 is offline stratus46  United States
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You have been successfully busy! Congratulations. I like the look of your 16 char display. The reason I
didn't use those is because I sit about 10 feet away and want to read the displays as it is for a TV set.

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Old 16th December 2019, 03:07 PM   #26
os77 is offline os77
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Join Date: Dec 2010
Location: France - Gujan-Mestras
Hello,
I was certain that the brightness of the 14-segment displays motivated your choice.
So I set them to the minimum to not burn my eyes
I keep this software version with 14 segments display, because you are absolutely right:
we see absolutely nothing at 3 meters with LCD 16 chars.
--
OS
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Old 14th March 2020, 05:18 PM   #27
rvega is offline rvega
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Default Where to find the NJW1119A ?

Thanks for all this info, @stratus46

Can you tell me where you found the NJW1119A for purchase in small quantities?
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Old 14th March 2020, 08:13 PM   #28
stratus46 is offline stratus46  United States
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Location: Los Angeles
Quote:
Originally Posted by rvega View Post
Thanks for all this info, @stratus46

Can you tell me where you found the NJW1119A for purchase in small quantities?
I bought them back in October of 2018 and did NOT proceed with anything until I had them
in hand. If I remember correctly, they were 10 for $18 from AliExpress. This is what they
have today which is still a good deal.

new NJW1119AV TE1 NJW1119A SSOP32 NJW1159M NJW1159 NJW1159M TE1 dmp16 5pcs|Relays| | - AliExpress

What project are you working on? I can tell you the chips work well. The software to load them
took me a while but you have the Arduino code so it won't be a big deal change it for your use.
I did change the capacitor values for the bass to lower the boost/cut frequency. The data sheet
calls out 100nF but I changed it to 220nF but I also bought 180nF. I don't remember which I
installed and since SMT caps don't have any numbers printed on them, I can't tell by looking.
Most of the signal caps are 2% film and the resistors are 0.5%. The 220nF were 20%. Bypass
caps are ceramic including the 100uF caps for the NJW chips. The only 'lytics are a pair of
2200uF organic polymers off the bridge.

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Old 15th March 2020, 12:12 AM   #29
rvega is offline rvega
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Join Date: Mar 2020
Thanks for the link and the info about the capacitors!


I want to build a 6 channel mono mixer for use with my live electronic music rig which consists of a handful of synthesizers and drum machines.



I want the mixer to be as small as possible so I want to put digitally controlled equalizers so I will only need three potentiometers and one button to control the eqs for all channels. The 1119A + a micro controller should allow for this.



This sort of interaction is used in some synthesizers like the Dave Instruments Prophet where you have one "layer" of timbre controls for each voice and a separate control to switch layers.
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Old 15th March 2020, 04:17 AM   #30
stratus46 is offline stratus46  United States
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Join Date: Nov 2009
Location: Los Angeles
Quote:
Originally Posted by rvega View Post
Thanks for the link and the info about the capacitors!


I want to build a 6 channel mono mixer for use with my live electronic music rig which consists of a handful of synthesizers and drum machines.



I want the mixer to be as small as possible so I want to put digitally controlled equalizers so I will only need three potentiometers and one button to control the eqs for all channels. The 1119A + a micro controller should allow for this.



This sort of interaction is used in some synthesizers like the Dave Instruments Prophet where you have one "layer" of timbre controls for each voice and a separate control to switch layers.

Depending on how fast you need to make changes you might look into using a 4 button up/down
left/right to step through your settings and then use a pot or raise/lower to control. An issue with
pots is that they inevitably get noisy which adds processing to control. Of course with the micro,
having multiple presets is also easy. I'm only thinking this way because the TV remote has those
buttons which is how I alter the tone settings of the 6 channels.

I'm adding the latest Arduino sketch as it tweaked the code a little specifically for the left/right
up down arrows to improve usability.

As far as small goes, if you're comfortable with SMT (no choice on the chip), each 2 channel group
of the NJW chip takes about a square inch. 0805 parts are small but not difficult to install. They
are also very tight on tolerance and not expensive. 0.5% resistors less than 4 cents in 100 lot from
DigiKey.

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File Type: txt LG_remote51T12.txt (32.7 KB, 8 views)
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