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perito industriale
2009-12-05, 08:40
Hello,
i turn to the technicians and designers of the apparatus, serebbe very nice if we could clarify some of my questions because I think the subject very interesting.
Any answers will be posted on other forums as Italians were no reports of common interest, there is great excitement around music liquid!



I'd like to understand the quality of the program used as a player and, above all, on what software rev ...

compete as a player is quality compared to PC player like Foobar 2000 + driver on Vista or WASAPI Seven, or an iTunes on MAC?

What kind of HardDisck support and what capacity?
They also support all USB HD 1TB?

perito industriale
2009-12-05, 15:44
is understandable my English?

bingcrosby
2009-12-05, 19:18
For people without knowledge of Italian, sarebbe = it would be.

For the most part, it is clear what you mean, capisco la maggioranza delle cose che hai scritto. If you look under the topic "Change power supply" there is some information about the hard drive support.

Ciao.

JohnSwenson
2009-12-05, 19:24
I think we are a little unclear about what you want to know. None of the squeezbox products use "normal" player software such as foobar etc.

The software is divided into two parts a server (Squeezebox Server) which runs on a separate computer of some sort. (except for the touch, which can run its own server) This server reads the files and sends the data over the network to the player, which has a fairly simple player which reads the data from the network and sends it to the internal DAC ship and to the the S/PDIF output circuit.

Yes there are versions of the server software and of the "firmware" running on the hardware, but they have no relationship to a version of any other software player such as foobar.

The software (both server and firmware) can pass data through unchanged (bit perfect). The players do have a digital volume control which can change the bits if you set it to less than 100%.

The Touch supports up to 24bit 96KHz so no sample rate conversion is done unless you are reading a file that has a sample rate higher than 96KHz. In such a case the sample rate conversion is performed in the server.

As to sound quality of the software its hard to compare to PC based software since the touch is not a PC. Hardware wise its closer to a small low power computer such as a FitPC slim. Since it runs linux a good comparison would be MPD running under linux on a FitPC slim. I have actually done this comparison and they are very close.

Since a number of people have done the comparison with MPD on a slim compared to foobar and other players on various PCS with various windows optimizations and almost always find MPD on the slim sounds significantly better than any of the PC configurations, the conclusion is that the touch is probably one of the best platforms out there.

Note this does NOT mean its the best sounding device on the planet, the DAC and clock jitter etc are very good but not the best on the planet. The S/PDIF out IS extremely good and probably one of the best out there. Its also possible by playing some games with the linux configuration to hook a USB DAC up to the USB port and this is one of the best USB connections for audio out there.

My personal opinion is that the Touch used from its audio outs is very good, definitely much better than you would expect from its price, but from its digital outs its phenomenal.

If that doesn't answer your questions let us know.

John S.

miab
2009-12-05, 23:36
John, when using Squeezebox server and Flac files does it decode the Flac files and then send the stream as pcm(or something else). Or does the Squeezebox server send out the stream as Flac and the Touch do the decoding?

pfarrell
2009-12-05, 23:41
miab wrote:
> when using Squeezebox server and Flac files does it decode the
> Flac files and then send the stream as pcm(or something else). Or does
> the Squeezebox server send out the stream as Flac and the Touch do the
> decoding?

All Squeezebox units since the SB-2 will natively process flac data. So
the server sends the flac and the unit decompresses it.

This saves a lot of wifi bandwidth, as flac are about half the size of
PCM. And if you have multiple hops, it can save four times the traffic.


--
Pat Farrell
http://www.pfarrell.com/

Themis
2009-12-06, 00:47
This saves a lot of wifi bandwidth, as flac are about half the size of
PCM. And if you have multiple hops, it can save four times the traffic.

Moreover, as it sounds different from PCM, you can use FLAC compression to act as a tone control. Ten different compression levels = ten different setups ! :D

Phil Leigh
2009-12-06, 00:52
Moreover, as it sounds different from PCM, you can use FLAC compression to act as a tone control. Ten different compression levels = ten different setups ! :D

:-)

Mnyb
2009-12-06, 01:17
Sssh don't :-) :-) even your joking can contribute to the myth that lossles formats sounds different ( which they per definition can not).

On topic .

One of the main points of getting an squeezebox is that its indeed independent from yoyr PC's os sound card and drivers thus works independently of any software or player on your pc, no need to fiddle with asio drivers or kernel streaming. The PC hosting the server application don't need to have audio at all. Also the squeezebox is not another soundcard.

The other biggie for audiophiles is that as it is network thing, that noisy computer can be somewhere else, in the basement or in a closet. Who needs a noisy pc close to the hifi ?

The Radio and multiroom functions is pleasant bonus for an audiophile. The non audiophile buyer might see it the other way around.
The cool thing is that it can be provided with same device :) we "only" add our favorite DAC or Processor then it's done.

c3p0
2009-12-06, 02:23
CD PLAYER: CD read by laser converted to PCM (a Data set pulses) and sent to a DAC which converts it to analog.

Several things affect the sound; the accuracy of the laser and error correction circuitry convert the CD on the fly to PCM and the DAC output stage used. All this is done in real time and the music output changes slightly each time you play the CD.

Computer: CD read and error corrected accuratly because time not important, can be BIT perfect if using the EAC program. It can now be converted to a format like FLAC. FLAC takes up less space than PCM, so you can store more music and transmit it quicker.

The FLAC can be sent to a Squeezebox by WIFI or ethernet. The electronic circuitry in the Squeezebox reconverts the FLAC to the PCM file (exact conversion: hence Lossless). The PCM is then sent to a DAC (built into the Squeezebox or external) which converts it to analog.The music output is always the same for the same music file.


CD player and Squeezebox sound different for the same Music because the DAC output stage is different and the PCM input is variable on the CD player.

With the Touch; it acts like a mini PC for handling music files and can handle up to 24/96 format, a cd is limited to 16/48.

if you attach a Hard disc to the TOUCH, it can access the music files on that disc directly.
if you connect the Touch to a network, the hard disc becomes a network disc and music files can be sent to it by other network users and even received from it.

you can simulate the Squeezebox even the TOUCH by using the free software in the download section. This will allow you to see how it handles music files and compare it to Itunes, you can even use Itunes to feed the Squeezebox (except for FLAC files).

The only thing you need for the TOUCH is some way of getting music files to it and amplifying the Sound out of it.

perito industriale
2009-12-06, 04:19
Thanks to everyone for the answers.
Probably there is some small misunderstanding but the general sense of the debate had been understood.

Foobar and iTunes, are considered the best currently available Playa completely freeware.

The quality of music reproduction really depends on:

The play that reads the file

The DAC converts

The output stage that amplifies

I am interested in using the Touch only as a player.
I wanted to know if the quality was comparable to DAC equal to that of a PC.

The speed with finding the tracks on the hard disk is important to try to see if I find the mortgage that I advised C3P0

Forgive me and google translator :-))

ModelCitizen
2009-12-06, 04:31
The speed with finding the tracks on the hard disk is important to try to see if I find the mortgage that I advised C3P0.
Google is not perfect then?

MC

perito industriale
2009-12-06, 04:59
you can simulate the Squeezebox even the TOUCH by using the free software in the download section.

Can you give me the exact link please?

c3p0
2009-12-06, 05:40
http://www.logitechsqueezebox.com/support/download-squeezebox-server.html

and follow instructions from there.

According to the Beta Testers for the TOUCH:

the audio out is very good, an improved DAC is used, better than previous versions apart from the much more expensive (Troppo Caro) Transporter.

The Digital Out is very very good with very low Jitter, so feeding an external DAC is improved

As a standalone player feeding and amplifier, the TOUCH will be one of the most cost efficient ways of getting Audiophile sound up to 24/96 and if you use a better DAC it will just even better up to 24/192 and beyond (see new SIMAUDIO Moon 32 Bit DAC/Transport)


You will have to wait with the rest of us to get your hands on the TOUCH, dont think it will be under my tree this Christmas, but soon I hope.

perito industriale
2009-12-06, 06:15
the link you give me leads to this page,

Download Squeezebox™ Server

but I did not find any beta testers for the touch

sono impedito?:-))

Phil Leigh
2009-12-06, 06:30
the link you give me leads to this page,

Download Squeezebox™ Server

but I did not find any beta testers for the touch

sono impedito?:-))

The Touch Beta testers generally agree with C3P0's statements above.
(well, I certainly do.)

c3p0
2009-12-06, 08:37
There are several items to download:
squeezecentre: acts like iTunes but doesn't rip CDs
squeezeplay; simulates Touch screen visually bit also allows you to hear the music rather than just control it; ie
squeezecentre ----controls Audio to squeezebox
squeezeplay------- plays audio on pc

so look for the version that works with your PC type, windows, Linux, mac

the physical squeezebox will out perform any Pc standard audio card.

The beta testers are a group of people who Logitech gave TOUCH's too in order to road testvthem prior to launch and feedback improvements and bugs.

liffy99
2009-12-07, 01:57
So does this mean that a Touch, wired to an external Hard Drive (how noisy are the stand alone ones) would remove the need for a NAS ?
Presume not if more than one Touch is used (e.g. in another room).
Also to get files on and off the hard drive would probably mean hooking up a laptop every time.

lrossouw
2009-12-07, 02:22
So does this mean that a Touch, wired to an external Hard Drive (how noisy are the stand alone ones) would remove the need for a NAS ?
Presume not if more than one Touch is used (e.g. in another room).
Also to get files on and off the hard drive would probably mean hooking up a laptop every time.

You are right. Apparently you could go NASless/serverless. I also understand that the Touch running in this manner could act as a server to other players (SB3, Radio, Boom, Controller, Receiver & another Touch). I expect that you won't be able to run any resource intensive plugins or transcoding.

Also the webinterface would not be available on the PC.

ModelCitizen
2009-12-07, 03:19
Also to get files on and off the hard drive would probably mean hooking up a laptop every time.

Other players can access the music library held on a Touch-attached drive.
You can share the files in a Touch-attached drive to your network (via Samba)

Cool huh?

MCh

Kevin Haskins
2009-12-08, 12:32
The quality of music reproduction really depends on:

The play that reads the file

The DAC converts

The output stage that amplifies

I am interested in using the Touch only as a player.
I wanted to know if the quality was comparable to DAC equal to that of a PC.

The speed with finding the tracks on the hard disk is important to try to see if I find the mortgage that I advised C3P0

Forgive me and google translator :-))

I think people should also keep some perspective. The distortion we see in even high-end loudspeakers is on the order of 10-100 times worse than what you pick up from any of these components. Perspective can help you make good purchasing choices. ;-)

perito industriale
2009-12-08, 12:43
I think people should also keep some perspective. The distortion we see in even high-end loudspeakers is on the order of 10-100 times worse than what you pick up from any of these components. Perspective can help you make good purchasing choices. ;-)

certain but I was talking about the source in this case

Kevin Haskins
2009-12-08, 13:06
certain but I was talking about the source in this case

Sure.. I'm just pointing out that if you cannot hear a difference, then it doesn't matter. You don't get brownie points for making something less inaudible.

I think the Touch used as a server and outputting via SPDIF directly into a DSP or a DAC is the cat's meow. I see no reason why you need to spend more for that task.

perito industriale
2009-12-08, 14:19
Sure.. I'm just pointing out that if you cannot hear a difference, then it doesn't matter. You don't get brownie points for making something less inaudible.

I think the Touch used as a server and outputting via SPDIF directly into a DSP or a DAC is the cat's meow. I see no reason why you need to spend more for that task.

well,
depends that which are the quality of the speakers utilized, the environment and which is the ability to hear differences. :-)) For most people is enough quality mp3 that does not mean it's the best, the difference between an mp3 and a wav file I think it's recognizable by equipment of average quality.
Certainly if there is some component that prevents the plant to hear these differences is pointless to change the DAC
I will experiment with the internal DAC of the Touch but I think i will use the coax output to connect an external DAC like the Musical Fidelity VDAC that promises good performance at relatively low cost ....

Themis
2009-12-08, 15:07
I will experiment with the internal DAC of the Touch but I think i will use the coax output to connect an external DAC like the Musical Fidelity VDAC that promises good performance at relatively low cost ....
I'll wait until I can listen to the Touch myself, nevertheless, all information gathered around converges to one point : you will probably need a much better dac than the V-dac to outperform it. ;)

perito industriale
2009-12-08, 15:35
I'll wait until I can listen to the Touch myself, nevertheless, all information gathered around converges to one point : you will probably need a much better dac than the V-dac to outperform it. ;)

The modified VDAC
output stage and power more parties .. you point to savings from a good base.
The DAC chip used in VDAC is good the rest can upgrade

Kevin Haskins
2009-12-08, 15:36
well,
depends that which are the quality of the speakers utilized, the environment and which is the ability to hear differences. :-)) For most people is enough quality mp3 that does not mean it's the best, the difference between an mp3 and a wav file I think it's recognizable by equipment of average quality.
Certainly if there is some component that prevents the plant to hear these differences is pointless to change the DAC
I will experiment with the internal DAC of the Touch but I think i will use the coax output to connect an external DAC like the Musical Fidelity VDAC that promises good performance at relatively low cost ....


I design transducers so I can safely say, it doesn't matter how much you spend, or what the marketing department says, the very most expensive and best loudspeaker has orders of magnitude more distortion than does the DAC in the Touch. ;-)

That is my only point.

pfarrell
2009-12-08, 15:40
Kevin Haskins wrote:
> I design transducers so I can safely say, it doesn't matter how much
> you spend, or what the marketing department says, the very most
> expensive and best loudspeaker has orders of magnitude more distortion
> than does the DAC in the Touch. ;-)

A related point: Often speakers are located in the wrong place. Huge
improvements in sound can be had for no money, just move the speakers.

--
Pat Farrell
http://www.pfarrell.com/

perito industriale
2009-12-08, 15:52
I design transducers so I can safely say, it doesn't matter how much you spend, or what the marketing department says, the very most expensive and best loudspeaker has orders of magnitude more distortion than does the DAC in the Touch. ;-)

That is my only point.

But that got to do!
You're comparing 2 different things. You can not compare the distortion of the signal and the power .. :-O
Distortion then is not the only parameter on which you decide the quality of a component hifi / hiend!
is important but not the only, if you're a designer you should know

Kevin Haskins
2009-12-08, 20:52
But that got to do!
You're comparing 2 different things. You can not compare the distortion of the signal and the power .. :-O
Distortion then is not the only parameter on which you decide the quality of a component hifi / hiend!
is important but not the only, if you're a designer you should know

THD+N is pretty useless as a sole metric, that is true. Especially with loudspeakers where the on/off-axis FR measurements are more important. But... when you are splitting hairs over 0.005 THD+N Vs. 0.0001 THD+N, it is almost guaranteed that there is little audible difference between the two. Also, you have to more broadly define how it is measured. Small amounts of odd-order are very audible, higher amounts of even order harmonics much less so. Also, you would have to know where the distortion components are in relation to the frequency band. You can listen to 10% THD at 20 Hz and not tell a distorted sinewave from an undistorted one. So... yes, it is more complicated than a simple single number but there is plenty of research showing what is and what is not audible.

With transducers, we are very happy to get 1% THD+N at higher listening levels. Those distortion products are both even & odd order depending upon the mechanism causing them. I'd say we are pretty safe in saying that those non-linearities swamp those that are another 40-60dB further down. It is like saying you can appriciate the sound of your hifi while using your chainsaw. Nobody would consider that a rational exercise, yet we routinely make such comparisons when judging audio components. The rational person, turns off the chainsaw before they fine tune their audio system for best performance. The irrational person quibbles about the nuances of the performance while ignoring the chainsaw.

perito industriale
2009-12-09, 02:07
THD+N is pretty useless as a sole metric, that is true. Especially with loudspeakers where the on/off-axis FR measurements are more important. But... when you are splitting hairs over 0.005 THD+N Vs. 0.0001 THD+N, it is almost guaranteed that there is little audible difference between the two. Also, you have to more broadly define how it is measured. Small amounts of odd-order are very audible, higher amounts of even order harmonics much less so. Also, you would have to know where the distortion components are in relation to the frequency band. You can listen to 10% THD at 20 Hz and not tell a distorted sinewave from an undistorted one. So... yes, it is more complicated than a simple single number but there is plenty of research showing what is and what is not audible.

With transducers, we are very happy to get 1% THD+N at higher listening levels. Those distortion products are both even & odd order depending upon the mechanism causing them. I'd say we are pretty safe in saying that those non-linearities swamp those that are another 40-60dB further down. It is like saying you can appriciate the sound of your hifi while using your chainsaw. Nobody would consider that a rational exercise, yet we routinely make such comparisons when judging audio components. The rational person, turns off the chainsaw before they fine tune their audio system for best performance. The irrational person quibbles about the nuances of the performance while ignoring the chainsaw.

The distortion of 0.0001 in the mountain can generate a much larger distortion because in our downstream facilities are amplifiers that amplify everything that goes into even the input distortion ...
The DAC is selected if you want to increase the detail or to gain a better scene to your own tastes.
You say that beyond a certain threshold rather low, (the DAC of the Touch is pretty cheap) do not feel more different.

This is not true.

Want to support that most audiophiles are deaf?
There is an explanation to this.
The human ear is an instrument that has had thousands of years of evulution.
What we feel is interpreted by the brain.
This explains why there is a DAC with the same distortion feel differently from other DAC.
Our ear is able to distinguish small changes that occur in a very short time, while great changes continue over time are not assimilated in the same way.
Here because we feel the differences between a cable and the other in the presence of a chainsaw :-))
I know that we are slightly off-topic:-D

Phil Leigh
2009-12-09, 12:14
The distortion of 0.0001 in the mountain can generate a much larger distortion because in our downstream facilities are amplifiers that amplify everything that goes into even the input distortion ...


Nonsense. The 0.0001 is a percentage. It is the ratio of distortion to sound that matters and that is constant regardless of how much it is amplified!

Themis
2009-12-09, 15:41
The modified VDAC
output stage and power more parties .. you point to savings from a good base.
The DAC chip used in VDAC is good the rest can upgrade
Why not getting a Northstar dac, or similar, used, rather than upgrading a cheap dac ?

perito industriale
2009-12-10, 07:45
Why not getting a Northstar dac, or similar, used, rather than upgrading a cheap dac ?

Apgrade only output stage, and power supply.
The vdac is a hiend product, not look at the price.
To buy something like that should be paid your price x40.
was compared with EMM Labs DAC is one of the best ever, if not the best and are very similar already without modification.

Themis
2009-12-10, 12:13
To buy something like that should be paid your price x40.
was compared with EMM Labs DAC is one of the best ever, if not the best and are very similar already without modification.
Sorry to say, if a guy thinks that a v-dac is "very similar" the EMM Labs dac, then I can see only two possible solutions :
- The guy is inventing things.
- The guy thinks that ALL dacs are the same. ;) (which can be easily proven with any AB/X test)

There's a bit more than an output stage in a dac, want it or not.

perito industriale
2009-12-10, 12:32
Sorry to say, if a guy thinks that a v-dac is "very similar" the EMM Labs dac, then I can see only two possible solutions :
- The guy is inventing things.
- The guy thinks that ALL dacs are the same. ;) (which can be easily proven with any AB/X test)

There's a bit more than an output stage in a dac, want it or not.

You can think what you want :-)
no problem.

all the DAC sound the same is not true, the ECHO for example is a good card but not at Levels of VDAC, is middle class.
The VDAC has a Hi End Audiophile setting while ECHO has a sound monitor.
It puts forward the sound and the reverberations hiding olophonia

Themis
2009-12-10, 12:34
It's your money. :)

perito industriale
2009-12-10, 12:43
It's your money. :)

yes! .. for 250.00 euro no one dies we say in Italy :-)))