question to Squeezebox Touch users

[chipzahoy]

If soundchek is trying to sell the mods for $300 a pop, then yes, your request would be perfectly reasonable.

Keep in mind that soundchek is offering to share his work for free. Nada. All he asks in return is a comment from those who like the mods. So why would he invest extra time, effort, or money to "sell" the mods to some random guy? I know I wouldn't.

Ironically, the commercial modding firms almost never provide measurements or concrete evidence to justify their expensive services. They are the ones you should crusade against, not a fellow Diyer.

 

[soundcheck]

Hi,

I have been following this thread about the squeezebox touch. I'm thinking of getting one.
@Soundcheck- I read about your proposed mods, if you disable the screen there is no real reason for getting the SB Touch. Is there any other device out there that would do the same job instead of the Touch?

Thanks

I summarized a thread / a discussion at SB Touch forum:

Please Build a DUET II

I guess that'll answer your question.

The Touch has a better PS and a better digital output section (I2S reclocker),
compared to the DUET. That's great.

The problem: They build so much other stuff into that box plus a Linux OS , that all this almost neutralizes the gain they made there with the new audio path.


My message: Avoid as much interferences/inter-modulations as you can, provide best power as you can you can, take everything out what's not required.

Less is more, avoid problems before they occur.

That's applied to the physical and SW side of my entire chain.


You might want to read the EC-Designs threads (e.g. SD-card player). You'll get an idea what I am talking about.

Cheers

 

[EUVL]

A friend has a DUET, and we build external supply and reclocker anyway.
So what else to mod on the DUET would you recommend ?

BTW thanks for sharing all your work with us.


Patrick

 

[soundcheck]

Keep in mind that soundchek is offering to share his work for free.

I am a Linux guy. The Linux world is a different world. It's free. It's still kind of idealistic environment in certain areas.

People spent thousands of hours on SW projects and don't ask for any return. That's common sense.

Most of the people involved work together pretty constructive, to get projects done.

Just a very, very few people do that in the (DIY-) audio world. It's rather the other way around. Even an exercise of 15minutes to apply my proposals is too much. They rather spent 300$ for a powersupply, because a hundred people are raving about it.


Not to forget though: The Linux - the heart - of the Touch is opensource-freeware too!!! Countless unpaid hours of work are in there.

There are a hundred of people who write plugins etc. at no cost "for Logitech". Though this must be considered a win/win situation. Logitech offers a reasonable priced platform.


Everybody is invited to join the club to contribute in a constructive manner.

Criticism is one thing. People being destructive another. Those people for sure discredit themselves with such an attitude.

Nada. All he asks in return is a comment from those who like the mods.

Because I am getting really annoyed of of all these destructive discussions.
I do not intend to sell these mods, by telling a thousand times what's gonna
be expected and to prove it.

I didn't describe any details what to expect after the mods on purpose.
Just to avoid biasing people.

One thing I can say. The ones who came back (THX for that) with
a comment by now, summarize pretty well what's gonna happen.

As you can see, even Sabre DACs, which are known for a pretty good jitter rejection, tell you what's going on.

Cheers

 

[psgr]

Soundcheck- Thank you for the pointers. I need to do more reading.
I do not doubt your mods, they make scene to me.
Initially when I posted, I was thinking of a device like the old Hauppauge Media MVP or the Duet, latter another device came to mind, the Dreambox dm500s. The dm500s is easy to get(online), it's inexpensive (about $100 shipped), it has ethernet and Spdif. I'm not sure what else is under the hood, and if the architecture is suitable for this application, but I know that it could be flashed with a custom kernel.

Again thanks for your input

Pete

 

[mb]

Soundcheck, thank you for sharing your experience.

I have just purchased my SB Touch, and in the past 2-3 weeks I have been checking the audio chain on linux (both alsa and pulseaudio, on ubuntu and debian).

I have found that alsa does not always retain integrity of the audio format: eg. 24-bit flac going to an integrated sound card capable of S32_LE (accepts 24-bit audio in 32-bit word) is converted by alsa to S16_LE. On the other hand, if the same audio is sent to a 24-bit capable USB card, the data is sent in full 24-bit format, as far as I can tell.

Have there been checks to verify that SB Touch does not reformat 24-bit audio to 16 bits before sending it to the hardware? Scanning the source code for squeezeplayer, I believe it uses portaudio, and my concern is that portaudio may not be 24-bit clean, and if the audio section of the SB is anything like many PCs, alsa will convert down (that seems to be the default action on alsa using S32_LE devices in hw mode) instead of reformatting 24-bit to 4-byte S32_LE.

 

[phofman]

I have found that alsa does not always retain integrity of the audio format: eg. 24-bit flac going to an integrated sound card capable of S32_LE (accepts 24-bit audio in 32-bit word) is converted by alsa to S16_LE. On the other hand, if the same audio is sent to a 24-bit capable USB card, the data is sent in full 24-bit format, as far as I can tell.

How exactly did you arrive at this conclusion? Alsa itself does no format conversion, unless it is instructed to do so. In many cases it is the application itself, e.g. mplayer was fixed only in the latest svn version.

 

[mb]

How exactly did you arrive at this conclusion? Alsa itself does no format conversion, unless it is instructed to do so. In many cases it is the application itself, e.g. mplayer was fixed only in the latest svn version.

Thanks for the clarification. Yes, you are correct, it's the applications. It would be good if 24-bit was always sent to a card in 32 bits when needed. It seems to make sense. Thanks also for the update on mplayer.

When checking out squeezeplay on debian and ubuntu without pulseaudio, I observed that a 24-bit flac would be output to the built-in soundcard in S16_LE format. Yes, not strictly an alsa issue, but my main concern is that (too) many programs appear to default back to a narrow format. Where the program allows the alsa device to be chosen, then using plughw as you have suggested to me in another post does the trick.

 

[Javin5]

Question to Soundcheck:

Maybe this is a bit offtrack, but do you have any experience with the Logitech Transporter? How would its SQ compare to the Touch (modified and unmodified) if you feed both via cable from the server? Assuming an external DAC.

I'm not sure which one I should buy at the moment. I realize that the transporter costs quite a bit more, but I read that it is also better made, for example it uses Jung Superregs inside. But would I get really better SQ for the higher price?

Thanks for any input.

 

[phofman]

When checking out squeezeplay on debian and ubuntu without pulseaudio, I observed that a 24-bit flac would be output to the built-in soundcard in S16_LE format. Yes, not strictly an alsa issue, but my main concern is that (too) many programs appear to default back to a narrow format. Where the program allows the alsa device to be chosen, then using plughw as you have suggested to me in another post does the trick.

Looking at squeezeplay source code, the device may be specified in alsaPlaybackDevice in the config file, see http://svn.slimdevices.com/repos/ji...rc/squeezeplay/src/audio/decode/decode_alsa.c . Other programs may read the sound card name from shell variable etc. You can always redefine the default device in your .asoundrc to be handled by the plug plugin.

 

[mb]

You can always redefine the default device in your .asoundrc to be handled by the plug plugin.

Thanks. I have done that (created a plug what will do the correct S24_LE to S32_LE if the card does not have S24_LE support), and mplayer, exaile, decibel all retain the audio word depth. That's good news.

Initial testing on squeezeplay one ubuntu or debian using alsa however shows the same audio file being sent out on S16_LE.

My main interest is the actual Squeezeplay Touch -- has anyone verified that the output (from SPDIF) is really 24-bit when the audio source is 24-bit? I'm sure the sample rate is correct, just concerned it truncates the word depth somewhere in the software..