'Analog Dinosaur' succumbs to the joys of FBA : enter Raspberry Pi 2/IQ-Audio DAC+!!

[Marco]

Hi Richard,

Sorry, that might have been a bit vague - What I meant was that I'm enjoying the new DAC so much that the Naim DAC could be in serious danger of being sold on, which means I'll have the funds for a cartridge upgrade ;-).

Ah, gotcha now. Nice one

One thing I noticed, and I guess this is the same trouble you've had Marco - is that when you disable the mixer, that seems to lock the volume at whatever it was set to last. The fresh Volumio install set the voume somewhere around 54% which is probably wise to avoid anyone blowing their speakers if they're going straight into a power amp, but I expected that disabling the mixer would have locked it to 100% volume without having to do anything else, but it looks as if you have to manually set the volume to the level you want it to be locked at first.

Yeah, that's exactly the case (as a friend with a Pi/IQ-Audio DAC has confirmed it), although I haven't tried it yet. Therefore, it looks like what Mike said earlier was wrong...

That said, even with the bad recordings, this DAC seems to be pulling everything out, so you find that you're never really getting distracted or focusing on the bad bits, but because the whole picture is being presented to you, there's always something interesting going on. Time will tell whether I start to shy away from the poorly recorded stuff. I have a feeling I won't because this isn't what I would call a 'warts and all' presentation, merely a clean window into the recording

Yup, the honest, 'open window' style of its presentation, coupled with its inherent musicality (as you say, making all styles of music and recordings interesting to listen to in their own right) is precisely what I like about the Pi/IQ-Audio combo.

There's also no 'glare' or 'edge' to the sound, such is normally the case when one listens to digitally reproduced music, but neither is it even remotely 'rounded off', so leading edges have all the requisite attack, in order to preserve the full quota of the music's fundamental 'excitement', thus encouraging long listening sessions into the small hours of the morning!

I think you're experiencing a similar thing...

Interesting that the Pi/IQ0Audio DAC is outperforming your considerably more expensive Naim. I'm not surprised though, as this little thing is undoubtedly capable of outperforming many much more expensive DACs and 'audiophile-badged' FBA sources.

It is, quite frankly, ridiculously good for the money - or indeed many multiples of money more than it. As such, more folk really do need to jump on and enjoy the ride aboard the Pi bus!!

Marco.

[Jimbo]

"There's also no 'glare' or 'edge' to the sound, such is normally the case when one listens to digitally reproduced music, but neither is it even remotely 'rounded off', so leading edges have all the requisite attack, in order to preserve the full quota of the music's fundamental 'excitement', thus encouraging long listening sessions into the small hours of the morning!"

Thats what you generally get with ripped CD via FBA system. Sounds much more pleasant

[Marco]

I do agree, Jim. However, the effect is more fundamental and unique to this particular combination, which I suspect is mostly down to the design and technical/sonic accomplishments of the IQ-Audio DAC.

Sonically and musically, it really is a very special piece of kit, at a (frankly) bonkers low-price....

Marco.

[Tim]

Thats what you generally get with ripped CD via FBA system. Sounds much more pleasant

Yup, spot on James - people who dismiss it because it's digital are missing out, it sounds nothing like a normal CDP.

[Qwin]

I did a bit of digging, so here goes with a non too technical explanation of what makes this thing tick.

The audio is handled by an i2s serial bus (data transfer method), this only handles audio and is not busy handling lots of other traffic. Most systems use i2s but hand the audio over to the USB bus for output. The USB bus also handles traffic from other devices running at the same time, so I think you can see the benefit of using the cleaner path by using only i2s.

i2s usually shunts audio data around from chip to chip on the PCB and USB is more about shunting data from device to device, that would be the simplest way of looking at it.

To take best advantage of the Rpi system you need to use the piggy backed DAC that plugs directly into the i2s bus. If you use an external DAC connected by the USB you are not really benefitting over any other PC based system.

USB can handle up to 24bit 96kHz in one direction.
i2s can handle up to 64bit 192kHz in one direction and 64bit 96kHz bi directional.
So in theory i2s is better placed for handling high quality audio files. I don’t know if it is fully utilized on the Rpi but in theory it is a good way to go for HQ audio.

The second area where benefits are likely being gained, is that the Rpi is a simple piece of computer hardware, with fewer things going on to get in the way of running audio. One of the things that builders of PC based FBA systems do, is strip out all the unnecessary parts of the system, removing things that get in the way or are a drain on resources and not needed for running audio files, removing both hardware and software routines. No need to do that on the Rpi its allready stripped down to the basics.

So those seem to be the advantages, which I can see how they might contribute to quality audio.

[Darren66]

Have been reading through all this with great interest. At the moment I use flac and wav files on HDD into laptop running jriver 20 into DAC,then into Cambridge Audio 840a amp. So with the pi2/IQ-Audio DAC+ People are talking about connecting to pre amp or power amp.Does any one know if you connect to a intergrated amp you loose some of the benefits of this set up. I'm new to this so if it's a stupid question I apologise.
Thanks Darren.

[r100]

Have been reading through all this with great interest. At the moment I use flac and wav files on HDD into laptop running jriver 20 into DAC,then into Cambridge Audio 840a amp. So with the pi2/IQ-Audio DAC+ People are talking about connecting to pre amp or power amp.Does any one know if you connect to a intergrated amp you loose some of the benefits of this set up. I'm new to this so if it's a stupid question I apologise.
Thanks Darren.

The IQ Audio DAC seems to be a bit special in the way it handles its output to the amplifier. But it and other Pi based DACs just plug into the integrated amplifier or pre or passive pre, just like any source would. I'm currently using a Sabre based board into an integrated amplifier with no issues.

[RichB]

I did a bit of digging, so here goes with a non too technical explanation of what makes this thing tick.

The audio is handled by an i2s serial bus (data transfer method), this only handles audio and is not busy handling lots of other traffic. Most systems use i2s but hand the audio over to the USB bus for output. The USB bus also handles traffic from other devices running at the same time, so I think you can see the benefit of using the cleaner path by using only i2s.

i2s usually shunts audio data around from chip to chip on the PCB and USB is more about shunting data from device to device, that would be the simplest way of looking at it.

To take best advantage of the Rpi system you need to use the piggy backed DAC that plugs directly into the i2s bus. If you use an external DAC connected by the USB you are not really benefitting over any other PC based system.

USB can handle up to 24bit 96kHz in one direction.
i2s can handle up to 64bit 192kHz in one direction and 64bit 96kHz bi directional.
So in theory i2s is better placed for handling high quality audio files. I don’t know if it is fully utilized on the Rpi but in theory it is a good way to go for HQ audio.

The second area where benefits are likely being gained, is that the Rpi is a simple piece of computer hardware, with fewer things going on to get in the way of running audio. One of the things that builders of PC based FBA systems do, is strip out all the unnecessary parts of the system, removing things that get in the way or are a drain on resources and not needed for running audio files, removing both hardware and software routines. No need to do that on the Rpi its allready stripped down to the basics.

So those seem to be the advantages, which I can see how they might contribute to quality audio.

That all seems like common sense to me Ken. A good explanation.

Whether the differences are within human perception though I guess we'll only know if we try.

[Marco]

Hi Ken,

Thanks for having a dig around and uncovering some interesting points...

The audio is handled by an i2s serial bus (data transfer method), this only handles audio and is not busy handling lots of other traffic. Most systems use i2s but hand the audio over to the USB bus for output. The USB bus also handles traffic from other devices running at the same time, so I think you can see the benefit of using the cleaner path by using only i2s.

The second area where benefits are likely being gained, is that the Rpi is a simple piece of computer hardware, with fewer things going on to get in the way of running audio. One of the things that builders of PC based FBA systems do, is strip out all the unnecessary parts of the system, removing things that get in the way or are a drain on resources and not needed for running audio files, removing both hardware and software routines. No need to do that on the Rpi its allready stripped down to the basics.

Indeed; all of which ably supports the mantra in audio I always champion, which is Keep It Simple, Stupid (the K.I.S.S principle). There's simply too much 'shite' going on inside most computers, in order for them to facilitate a quiet enough (and thus sonically optimal) environment for audio, and *that* is where the sheer design simplicity of the Pi/IQ-Audio DAC comes into its own!

NOTHING is in there that doesn't need to be.

To take best advantage of the Rpi system you need to use the piggy backed DAC that plugs directly into the i2s bus. If you use an external DAC connected by the USB you are not really benefitting over any other PC based system.

Again, that's precisely what my ears have (very clearly) told me. As you've outlined, the secret of the Pi/IQ-Audio DAC combo is in its simplicity, and the fact that everything has been so well thought out and implemented.

Therefore, adding an external DAC, which in all likelihood will be inferior to the IQ Audio, in this application, (not to mention interconnect cables liable to increase jitter), simply complicates matters, adversely effecting sonic synergy - and so is most likely a retrograde step.

USB can handle up to 24bit 96kHz in one direction.
i2s can handle up to 64bit 192kHz in one direction and 64bit 96kHz bi directional.
So in theory i2s is better placed for handling high quality audio files. I don’t know if it is fully utilized on the Rpi but in theory it is a good way to go for HQ audio.

I think the stats above say a great deal. As for whether or not the Pi is fully utilised for handling high-quality audio files, well if it isn't, then it'd hate to hear what it would be like if it was!!

Quite simply, this little thing, used in conjunction with the IQ-Audio DAC+ isn't outperforming vastly much more expensive equipment for nothing.

I think you're little 'synopsis' of why that might be gets pretty much to the heart of the matter, and the addition of a judiciously implemented high-quality linear PSU is only likely to further increase its efficacy, thus making the purchase of an RPi/IQ-Audio DAC combo a veritable no-brainer.

So when are you getting one?

Marco.

[Qwin]

I have a few other purchases for my system comming up but I can see me getting one of these fairly soon.