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Pre Raspberry Pi delivery question please.

Also I typed "digital" in the ALSA volume window, couldn't notice any real change after the reboot, what is it actually doing?

As covered in the IQaudIO instructions manual (http://www.iqaudio.com/downloads/IQaudIO.pdf), these DACs have an 'integrated hardware volume control'.

This means that, rather than sending a lower resolution signal (i.e., removing bits to lower volume via software) to the DAC, it is possible to send a bit-perfect signal to the DAC, at full resolution, and have a computer chip adjust the volume afterwards ("almost" as if you had an analogue pre-amp to adjust volume after the dac).

This is the feature which made me go for IQaudIO devices over the competition (as most lack this capability), even though I haven't done any sound quality comparison. I'd expect it to matter most when playing at low volume...

--

As you progress into Geekdom, you may want to connect to your Pi with a PC software called Putty, and follow the instructions at
https://sites.google.com/site/picoreplayer/home/how-to-1 once there to access the alsa-mixer command mentioned in the above IQaudIO document.

Google 'PuTTY download' to install this piece of software on your PC, run the programme called PuTTY, type the IP address (192.168.x.y) in the Host Name field, set connection type to SSH and press "Open". Then type 'tc' as login, and 'piCore' (case sensitive) as password.

You then see a command prompt... type 'alsamixer' to launch that command, then type 's' and select the IQaudIODAC entry (using the arrows on your keyboard). Navigate with the arrows the various 'potentiometers' to set them as per the IQaudIO document. Once done, press the Esc key and type 'exit'... Voila!

(depending on your browser settings, the graphics in alsamixer may not look very nice, but this doesn't matter for what we are trying to do here)

Good luck!
 
EIffel many thanks for that, great advice. I will honestly digest that now and act upon it.

I will also go and put "digital" into the box again.

Is it all lower case or a capital D please?
 
It is 'D' (capital).

To see the effect this has, while alsamixer is running, try adjusting the volume in SqueezePlay, the LMS home page, or whatever you use to control volume... you should see the 'Digital' cursor move up and down when this option is enabled.
 
I think I'll have to google that one Del, all new terminology to me.

Ssh (Secure SHell) is a way to get a text-based terminal connection to a computer - allowing you to talk directly to the command line interface (shell).
Putty is a windows program that allows you to do a ssh connection from a windows computer to another computer (running ssh).
 
Ah, thanks for that. It just confused me why I need this when I was able to type prompts in to the Volume box without having it.
 
Thanks, I probably will try again next week with that. I was just a bit worried by this PCM VBR FLAC thing that Tidal shows. Yet the menu says it is playing FLAC
FLAC is 'variable bit rate', and produces PCM. So I think you're OK.

PCM is constant bit rate, for example 44100 samples of 16 bits per second, two channels, gives 44100 * 16 * 2 bits per second, 1411200 bps, which is a lot when most of them are zero. FLAC does a loss less compression, so it will turn proper silence into a very small number of bits, and not do a very good job at all with perfect noise. So the resultant bit rate varies from moment to moment, but with 16 bit music averages about half the raw PCM rate.

Some of Jim Audiomisc's threads relate to how to do better than this at no subjective cost, prompted I think by the mumbo-jumbo surrounding MQA.

Your Pi is running a Linux distribution, which is a complete general purpose operating system you may have heard of, the suppliers you have chosen have stripped out a lot of the irrelevant clutter, installed the player and library components of their choice and skinned it with a web based interface to make it easy and relatively friendly. You can however connect to the underlying OS and work with it directly, SSH is the standard protocol for doing this nowadays, and PUTTY is the standard Windows application for the user end.

I've been using a Pi2 with a Hifi Berry S/PDIF output and a huge USB disk running Volumio to supply music at home for a year or two now. It works nicely enough, although a Pi3 might manage the large disk indexing better.

The Pi has 'I2S' support, which is the chip-chip digital audio standard, (when I first got involved there was no operating system support for this, so it was necessary to build a new kernel from source on a separate host. Nowadays it's put the card in the box and it just works. ) The Pi also supports I2C, which is a chip-chip control interface. So the DAC chip is configured via I2C and then the audio is played over I2S. If you configure the volume control in the operating system to the right type of 'digital' then I2C commands will be used to tell the DAC to change the volume, which is an ideal way to do it.

It's all so easy nowadays.

Paul
 
Ah, thanks for that. It just confused me why I need this when I was able to type prompts in to the Volume box without having it.

You'll find the Putty download under links on the Picore web page. Once downloaded you will be faced with a Putty page. You just addd the IP address of the PiCoreplayer, submit, enter the Username and password and you're in. You can see the alsa etc from here. Something to learn about over time.
Del
 
Paul, thanks a million for that detailed response. I understand it more now.

Some super info. there!!

Del. I shall be attempting that this afternoon for sure. Many thanks again. I will report back:)
 
Thanks Del. Downloaded and shortcut now on desktop.

So, I go in to Putty, and enter ipCorePlayer when asked for user name or IP address..

I then press yes on the warning notice to proceed.

It then asks me to type user name which I did, ie ipCorePlayer.

Screen then shows IpCore player> IP address.........but then says password: with a green block after it.

It will not let me then type any password. Apologies for the hassle!
 
Kenny, start again.

at the command prompt (green block) type

tc

and press enter on the keyboard.

at the next green block type

piCore

this password is case sensitive and nothing will show on the screen.

when you have finished typing, again press enter on the keyboard.

Ronnie


1picore%20putty_zps9ig9hdqy.jpg
[/URL][/IMG]
 
Cheers for the lift Ronnie.
Just tried that. Typed tc at first green prompt. Text then says "tc@Ipaddress. Then same again, I cannot type anything after second green prompt.
 
then type

alsamixer

press enter and you will get a screen not like this (different card)

if you want to select from a list, press the F5 key ont the keyboard and select

2picore%20putty_zpsmele3h5a.jpg
[/URL][/IMG]

to return to the previos screen press Esc button on keyboard.

On previos verssions of Picoreplayer one had to save the settings and the set them as default on the pcp web gui.

ronnie
 
Cheers for the lift Ronnie.
Just tried that. Typed tc at first green prompt. Text then says "tc@Ipaddress. Then same again, I cannot type anything after second green prompt.

after entering the user name "tc", press the enter button on the keyboard.

there will be a flashing green block on a new line

type the password

piCore

notthing will appear on the screen, just press the enter button again
 
Try this?

SSH into the pi:

User name:
Code:
tc

Passwd:
Code:
 piCore

Type
Code:
alsamixer
, press enter.

PressF6, select card from drop-down and adjust the volume using the up/down arrows on the keyboard.

Follow these instructions from Steen;

4. Next press escape to go to command prompt

5. Then save the changes to alsas config file by: sudo alsactl store

6. Save this file in piCore in order for it to survive a reboot: sudo filetool.sh -b

In order for piCorePlayer to use this alsa config file after a reboot, you must enable "use custom alsa settings" on the "tweak page" in piCorePlayers web-page

Next reboot - and hopefully it is working for you.

Steen
atb

Ronnie
 
Ronnie I think I've flooked my way in here. Cheers for your continuing patience!!

Entered tc as you said, then the original password I set up in Icoreplayer a couple of days back.

It then took me to a screen with core player where I entered "alsamixer" and ended up here..............

IMG_0352_zpsi8qhikle.jpg
 


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