iFi iPurifier: What is it? How to use it? Do I want it?

[sandyk]

Paul

Despite the claims of superior SMPS wallwarts being used, there appear to be a few failing.

Are the ratings marked on the wallwart itself ?

Alex

[Superdad]

I have a second iUSB Power unit here I cannibalized a power supply from. I thought about using my little laser power supply on it, but I wasn't entirely sure what the little beastie wants in terms on input.

 

That would be Thorlabs - LDS9 9 VDC Regulated Power Supply, 2.5 mm Phono Plug, 120 VAC.

 

I think your 220mA laser supply is not beefy enough for the iUSB. iFi's stock SMPS is rated at 1 amp. So be careful Paul. Of course in about a month you will have a 2-rail Swenson LPS from me to power whatever you wish!

 

Ciao,

ALEX

[Paul R]

I think your 220mA laser supply is not beefy enough for the iUSB. iFi's stock SMPS is rated at 1 amp. So be careful Paul. Of course in about a month you will have a 2-rail Swenson LPS from me to power whatever you wish!

 

Ciao,

ALEX

 

(grin!)

[sandyk]

Is it an advantage to have them all powered from the same Linear PSU, whether it has the capabilities or not ?

Perhaps a question for John Swenson ?

[fmak]

I think your 220mA laser supply is not beefy enough for the iUSB. iFi's stock SMPS is rated at 1 amp. So be careful Paul. Of course in about a month you will have a 2-rail Swenson LPS from me to power whatever you wish!

 

Ciao,

ALEX

 

It doesn't matter what the wall wart is rated at. USB does not draw 200mA. Try it and it should work.

[Superdad]

It doesn't matter what the wall wart is rated at. USB does not draw 200mA. Try it and it should work.

 

Uh, you should check the USB 2.0 spec. 500mA to 1A is not uncommon at all. And the specs for the iUSB as listed on iFi's web site say the device consumes a max of 9 watts. So at 9V input that's 1A.

[fmak]

Uh, you should check the USB 2.0 spec. 500mA to 1A is not uncommon at all. And the specs for the iUSB as listed on iFi's web site say the device consumes a max of 9 watts. So at 9V input that's 1A.

 

Most usb audio devices will work with 200mA. There is no harming in trying with one has got. All that is in the USB Power is a Jung type regulator which doesn't consume much in itself, and a 7th order filter.

[One and a half]

In use : ifiUSB and Purifier

 

Audiokette (I kind of like this term kette = chain, German language is great for making accurate descriptions by linking common words)

 

Mac mini USB3 --> Short blue USB cable supplied with ifi USB -->ifiUSB --> Oyaide Continental S5 USB --> Ranger 2224 USB extender --> IfiPurifier --> MPD-3 DAC. The earth on the iUSB was in the isolated position.

 

AC Power to all components was balanced 120-0-120 using wall warts for the iUSB and the 24Vdc for the Ranger.

Source music : Marialy Pacheco - Introducing 96/24. This is minimal on instruments just, piano, drums, bass, fantastic recording. The 9V wall wart of the iUSB even went through an isolation transformer additional to the balanced supply.

 

With the ifi devices installed as above, the mid to high treble attenuated, that decay on cymbals disappeared, the attack of the sticks went awol, the piano vanished somewhere in the mix beyond the grave, used to be across the whole board in front. Not what I would call an engaging performance, and hardly worth recommending. Don't bother.

 

There wasn't much joy with the iUSB before the Purifier, and the addition of the purifier didn't help at all. Do I put it down to the short USB cable supplied...tried with a Nordost Blue Heaven, no real improvement, wasn't expecting it, but you never know.

[Paul R]

I would chalk that up as your system not needing the kind of things the iFi iUSB or purifier does.

[One and a half]

I would chalk that up as your system not needing the kind of things the iFi iUSB or purifier does.

 

Ah yup, less is more!

[sandyk]

With the ifi devices installed as above, the mid to high treble attenuated, that decay on cymbals disappeared, the attack of the sticks went awol, the piano vanished somewhere in the mix beyond the grave, used to be across the whole board in front. Not what I would call an engaging performance, and hardly worth recommending. Don't bother.

 

One and a half

The "bits are bits" brigade would have serious issues with your report, especially as the binary data to the DAC is almost certainly 100% correct in both situations. It would appear that not only have you already markedly cleaned up incoming AC, but also prevented crap getting back into the mains again.

Alex

[One and a half]

One and a half

The "bits are bits" brigade would have serious issues with your report, especially as the binary data to the DAC is almost certainly 100% correct in both situations. It would appear that not only have you already markedly cleaned up incoming AC, but also prevented crap getting back into the mains again.

Alex

 

This is a classic case where what's riding on the 'bits is bits' is just about, but not completely gone, and adding in something else to overcome that is so small, it's like dividing by something close to zero, you start to gain. In this case the gain has adverse effects.

[4est]

Or more universally: the closer to the goal, the easier it is to make the wrong move.

This is a classic case where what's riding on the 'bits is bits' is just about, but not completely gone, and adding in something else to overcome that is so small, it's like dividing by something close to zero, you start to gain. In this case the gain has adverse effects.

[HumanMedia]

In use : ifiUSB and Purifier

With the ifi devices installed as above, the mid to high treble attenuated, that decay on cymbals disappeared, the attack of the sticks went awol, the piano vanished somewhere in the mix beyond the grave, used to be across the whole board in front. Not what I would call an engaging performance, and hardly worth recommending. Don't bother.

 

Exactly my experience with iPurifier.

And if its not making things better by removing electrical noise, then it shouldn't be affecting the eventual analog signal so negatively (as it does).

[sandyk]

Exactly my experience with iPurifier.

And if its not making things better by removing electrical noise, then it shouldn't be affecting the eventual analog signal so negatively (as it does).

 

It would be interesting to record both analogue versions in 24/192 to see exactly what has changed.

I have a sneaking suspicion though, that you will not find any differences by digital means , despite them being so audible.

I tried something similar a while back, recording in 24/96 and came up empty.

Alex

[One and a half]

Exactly my experience with iPurifier.

And if its not making things better by removing electrical noise, then it shouldn't be affecting the eventual analog signal so negatively (as it does).

 

It may gone too far with the filtering and adding more than required. This clearly means that the USB signal is affected by LCR just like any other analog waveform, debunking the bits is bits and all perfect digital signal myth. Unless the iPurifier reconstructs the whole shebang somehow and gets it wrong.

[kbkaran]

It may gone too far with the filtering and adding more than required. This clearly means that the USB signal is affected by LCR just like any other analog waveform, debunking the bits is bits and all perfect digital signal myth. Unless the iPurifier reconstructs the whole shebang somehow and gets it wrong.

hmm.. I dont know about the iPurifier but the iUSB cannot for sure make things worse. Oh.. try not isolating the ground. In my case, that was causing adverse effects. BTW, I think this is either jitter or some noise injection issue. iPurifier based on my reading it basically removes any DC component in the data lines. Are you sure the change in sound is bad ? Increase the volume than you are normally accustomed to and see if you can hear more details. You are probably already aware, with jitter, say for example, you pass a 5KHz tone in, you would get harmonics/sidebands. Getting rid of them 'quietens' the system which some times can be mistaken for lack of detail/life etc ( noisy club == fun , quite home == boring :-) )

[One and a half]

hmm.. I dont know about the iPurifier but the iUSB cannot for sure make things worse. Oh.. try not isolating the ground. In my case, that was causing adverse effects. BTW, I think this is either jitter or some noise injection issue. iPurifier based on my reading it basically removes any DC component in the data lines. Are you sure the change in sound is bad ? Increase the volume than you are normally accustomed to and see if you can hear more details. You are probably already aware, with jitter, say for example, you pass a 5KHz tone in, you would get harmonics/sidebands. Getting rid of them 'quietens' the system which some times can be mistaken for lack of detail/life etc ( noisy club == fun , quite home == boring :-) )

 

Appreciate the input here and where your'e coming from. Yes I'm sure the change in sound is bad, otherwise the report would have been glowing. The removing the DC component that the iPurifier does is interesting, I am wondering if the threshold of detection of the 0V is causing the problem, creating a false reference point and the SQ going downhill from there.

 

Maybe adding a tube in the line will overdrive harmonics and EQ the crud into nothing perceptible. Have you noticed more DACs than say a few years ago e.g. iFi Micro iTube are introducing tubes to 'tame' digital? Is the tube acting to filter something, can the tube pass RF or CM...?

 

I'm not sure if the iUSB corrects for jitter will have to research this a little more. You would have to have a reference level of some kind, maybe that was the idea of the IPurifier to at least make this stable and to clock on the real USB lines somehow. Just speculation here.

 

I tried various times to change the earthing, it didn't make much of change, but in other systems it would have a profound effect.

[kbkaran]

Appreciate the input here and where your'e coming from. Yes I'm sure the change in sound is bad, otherwise the report would have been glowing. The removing the DC component that the iPurifier does is interesting, I am wondering if the threshold of detection of the 0V is causing the problem, creating a false reference point and the SQ going downhill from there.

 

Maybe adding a tube in the line will overdrive harmonics and EQ the crud into nothing perceptible. Have you noticed more DACs than say a few years ago e.g. iFi Micro iTube are introducing tubes to 'tame' digital? Is the tube acting to filter something, can the tube pass RF or CM...?

 

I'm not sure if the iUSB corrects for jitter will have to research this a little more. You would have to have a reference level of some kind, maybe that was the idea of the IPurifier to at least make this stable and to clock on the real USB lines somehow. Just speculation here.

 

I tried various times to change the earthing, it didn't make much of change, but in other systems it would have a profound effect.

 

Right .. the ground reference is very important, Maybe you can try plugging all the components into one condtioner/power socket array. It should be ok to put the iUSB wallwart also there, atleast temporarily to debug the problem. Another possible issue might be the DAC is drawing more current from the USB lines than what the iUSB can deliver (for eg. in my case iUSB cannot feed my squeezebox touch. I dont know how in ifi docs and others manage to do this).

Re: tubes - I guess some people feel there is too much attack and too little decay in the digital world. Tubes can help in both situations (personally I am not sure tubes are high-fidelity). The attack/decay is also very noticeable when amplifying the vibrating stylus of an LP. To me LP sounds more 'real'. But then again it probably is not the actual recorded sound but a 'replay' of the original instruments (all my own arm-chair philosophising).

I dont think the iUSB has any digital circuits to correct jitter. Probably just buffering. Mainly it substitutes the USB's DC lines with a cleaner one.

[hifitubes]

I have one system using a PPA Studio USB card and it lets noise through to the DAC; readily apparent hash. The card doesn't have the same level of filtering as say the SOtM or JCAT.

 

I would be interested to hear what the iPurifier alone does on that system. The iUSB would also be welcome to that system; it has the stock SMPS Fortran powering the ATOM board.What is interesting is that the DAC I use, the Vega, does not even have the 5V pin connected at the input of the DAC - so this is riding Ground?

 

Using my Adnaco S3B, battery powered, results in a dead quiet system - in this case I would be leery of adding another component such as iPur or iUSB.

 

...food for thought

Appreciate the input here and where your'e coming from. Yes I'm sure the change in sound is bad, otherwise the report would have been glowing. The removing the DC component that the iPurifier does is interesting, I am wondering if the threshold of detection of the 0V is causing the problem, creating a false reference point and the SQ going downhill from there.

 

Maybe adding a tube in the line will overdrive harmonics and EQ the crud into nothing perceptible. Have you noticed more DACs than say a few years ago e.g. iFi Micro iTube are introducing tubes to 'tame' digital? Is the tube acting to filter something, can the tube pass RF or CM...?

 

I'm not sure if the iUSB corrects for jitter will have to research this a little more. You would have to have a reference level of some kind, maybe that was the idea of the IPurifier to at least make this stable and to clock on the real USB lines somehow. Just speculation here.

 

I tried various times to change the earthing, it didn't make much of change, but in other systems it would have a profound effect.

[tranz]

Well here is an idea as to why the iPurifier might do more harm than good. It has a stonking LED in the path. Perhaps I am missing it, but that does not seem ideal. There are little blocks over the paths on the board that look like ferrite and then short unshielded cable runs next to the LED to connect on the other end. Some pictures:

 

Inside:

 

Scope on the D+ or D- and ground with IFI iUSB (laptop on battery and iUSB on LPSU):

 

Same as above, but with iPurifier:

Hard to tell but it seemed noisier with the iPurifier.

 

Use a T-5 bit to loosen 4 screws to open.

[sandyk]

Trans

Does the Green LED light continuously as an indicator perhaps, or does it appear to be used as a higher forward voltage diode for some kind of limiting purpose ?

 

Kind Regards

Alex

[fmak]

Well here is an idea as to why the iPurifier might do more harm than good. It has a stonking LED in the path. Perhaps I am missing it, but that does not seem ideal. There are little blocks over the paths on the board that look like ferrite and then short unshielded cable runs next to the LED to connect on the other end. Some pictures:

 

Inside:

[ATTACH=CONFIG]12632[/ATTACH]

 

Scope on the D+ or D- and ground with IFI iUSB (laptop on battery and iUSB on LPSU):

[ATTACH=CONFIG]12633[/ATTACH]

 

Same as above, but with iPurifier:

[ATTACH=CONFIG]12634[/ATTACH]

Hard to tell but it seemed noisier with the iPurifier.

 

Use a T-5 bit to loosen 4 screws to open.

 

I cannot see inside because of opaque compound but the usb leads look messy. I tried to measure R,C,L across

the terminals (unpowered) but got nowhere and decided that there must be some active components.

 

Yes the iPutifier does more harm than good and may perhaps address issues with the stock wall wart, reducing hf

grit?

[tranz]

I cannot see inside because of opaque compound but the usb leads look messy. I tried to measure R,C,L across

the terminals (unpowered) but got nowhere and decided that there must be some active components.

 

Yes the iPutifier does more harm than good and may perhaps address issues with the stock wall wart, reducing hf

grit?

 

Hi fmak,

 

Cleaning up for the wallwart is a possibility as I took some interesting scope pictures of that as well. Using a cheap LPSU vs the IFI wallwart was no contest. The wallwart is far noisier.

 

Hi Alex,

 

Not sure if the LED has any other function, but it is on all the time once connected. Which means it draws its power from the 5v that I just cleaned up with the iUSB.

 

LEDs piss me off in general

[4est]

+1

LEDs piss me off in general