[kyrill]

I fell in love with the low jitter figures of Audiophilleo. Not that they are really  low to begin with but also of the many positive FB and reviews on the net. However I have already a very good USB converter the very very good JKenny MK2 which I would have sold in a second if it didn'd sound as a big improvement to my modded TEAC VDRS1 CD transport with a real good clock or Wayne modded SB3 with PHynes supply

But the MK2 of Kenny blew my TEAC in the water. I didn't even bother to sell it in order not to keep the new buyer in the "dark ages".

So I took the risk of buying the AP2 not really a risk as you will have a full refund  when sending back within 30 days.

This is my short review I send to Audiophilleo
=======================================
"I have mixed feelings about the AP2, however I have only 24+hrs continuous play and that is way beyond what I consider fair playing in time.
Still I begin to hear characteristics that are beginning to "open'  and develop. But most people will have a much inferior product in the house if
any USB/spdif converter to compare the AP2 with. I have John Kenny's MK2 modded to almost Mk3 status, with an external LifFE battery.

The JKenny "MK2.5" is already very good. Slowly now the AP2 is surpassing slightly the MK2.5 in every parameter. If this continue to develop
the AP2 will be better say a 9 out of 10 compare to the 8 of the MK2.5, but there is a BIG but. Compared to the Mk2.5 the AP sounds definitely
less organic, less "soft "as in life, which translates to musicality relative to each other.. The sound of the AP2 is more pristine studio like even with acoustic instruments
and it suggests better separation of instruments as the different sound identities are drawn much more clearer against space. But as it is now  these boundaries are enhanced, slightly emphasized like the fine black drawing in coloured strip books around the objects. For instance you can draw a tree with a fine black pen a tree with many leaves. Now color all the leaves and the trunk and you have
a very beautiful tree, while the real tree has no fine black lines enhancing the different forms from each other. The AP is the tree with those boundaries, High end want the true tree that does not need enhancing

I am almost sure that this about the switching dc-dc converter and the (common mode) noise out of the PC, which will be different with the possible AP battery version
I will  listen a week further then I am close to 200 hrs playing in time.

I really need to know however if the plans to help existing owners to upgrade to a battery version will actually happen in a reasonable time frame. If yes I will never send the unit back as I am convinced it may become the best in present world, equaling or surpassing the Off Ramp of S. Nugent. I don't know about the Berkeley  Alpha USB, I believe the Alpha USB will be less If I look at their marketing narrative."
It took some days to have their answer back

Since then with another 48 hrs play on top of 24+ hrs. the difference between the AP2 and JKenny's  become more profound in advantage of the musicality of the MK2. It is not mere "liquid" sounding, it is just plain more musical as in real life. I was thinking I may have to send the AP2 back in spite of its better sounding qualities in every other aspect except the musicality.

Then I got this nice mail back which made me feel well ehh like a kid in front of a nice adventurous journey:    ======================

"Thanks very much for the detailed feedback!  Indeed I believe you are correct in all your statements including that the battery supply will resolve the issue that you do have with the ap2. I am happy to hear that the ap2 compares well to a device that uses battery power, as I believe the battery supply will provide a considerable step up for the ap2…
The battery supply WILL come out in the next weeks and it will be $399 + shipping to do the upgrade. 

Cheers"
=======================================
So If you want happy  happy high end listening go for the battery upgrade, you will also hear more micro-details bigger 3D and all those magical moments.


So what about the AP sans battery? People who hate classical music, or don't care for acoustic instruments and are more geared to pop and rock on their "pop and rock" systems the AP as it already is will sound close to perfect. To define musicality of electronic instruments is a paradox, It depends on yr system as well, if it is already shrillish or not lacking tweeter energy buy the MK3 if it sounds really neutral to "soft" buy the AP, given these two brands, but there are many others, but not necessarily sounding better

So what about the MK2?
I will sell it to a friend with Martin Logan speakers. Burson audio amps and DAC , dedicated line conditioner, a tube buffer between dac and amp and  damping feet under all his gear and who does not have a dedicated room for listening without Wife*, kids and TV ( *except that wonderful woman who prefers listening in the evening, lights out above watching TV )

The MK2 however is superseded by the MK3 which I believe will be halfway the MK2 and the AP +battery. But look at the price difference a close to 1000 dollars for the battery powered AP2 to 430 dollars for the MK3

I would not be surprised that John Kenny in due time will come up with an adequate answer

[TomS]

Very interesting development and thanks for informing us. I have been very happy with the AP1 and would continue to invest in improvements for it if available at a reasonable cost. This sounds like a great option.

[Jon L]

Could you detail exactly how you made the DIY battery supply for Audiophilleo 2?  Looks like you are using Alkaline D batteries, which are 1.5V, so you are connecting 4 in series to end up with 6V? 

[kyrill]

Could you detail exactly how you made the DIY battery supply for Audiophilleo 2?  Looks like you are using Alkaline D batteries, which are 1.5V, so you are connecting 4 in series to end up with 6V?

Jon?
I never made a DIY battery for the Audiophilleo, I did one A123 LiFe battery made of 3 pcs so total 10V for the JKenny MK2

[Jon L]

I thought this was your post.  Check out the DIY battery PS in the middle of the page.

http://www.computeraudiophile.com/files/Audiophilleo%20vs%20Evo-%20Part%20%202%20and%203.pdf

Also, why pay $400 for AP2 battery pack when battery packs can be found for around $43 like this one?  One would need to rig up a USB adapter to cut off power from computer and supply from the battery like AQVox USB supply does.

http://www.amazon.com/New-Trent-iDual-Port-IMP50D-Blackberry/dp/B003690Q42/ref=pd_sim_sbs_e_6

[kyrill]

that post was from Kamil, btw a good review too.

The problem of the AP is twofold
1) dirty grnd, dirty 5V form the USB host ànd
2) dirty RFI all over the board and probably reflected by the small aluminum enclosure by its own switching DC-DC converter

the 5V from the USB host is the easiest to cure. The grnd problem much more complex  but with floating ground coming from the PC ( so the pc itself is has no contact to wall socket grnd much more easier to accomplish with a laptop) it may sound better but not really cured, grnd loops may be avoided that way. a real cure will be provided by Vaunix http://www.vaunix.com/products/high-quality-usb-hub/overview.cfm which has "digitalized"the grnd, the ground is galvanicly isolated as well the 5V out of the PC. But they also use their own switching on board VR
2) is a major internal mod in the AP but will be cured with their battery solution.

SO the AP battery version cures 2 out of 3 problems. For some reason designers of audio  computer solutions still  do not comprehend how very very dirty everything is coming out of digital  hardware including ground.

[jrebman]

Any updates on this?  I don't see any mention of it on their web site.

Count me as very interested.

-- Jim

[kyrill]

OK it happened
See their web site for VLN Pure Power

[kyrill]

see above

[jrebman]

Thanks, Kyril.

Payment is made and I'll ship it out today.

Thanks,

Jim

[TomS]

Thanks, Kyril.

Payment is made and I'll ship it out today.

Thanks,

Jim

My AP1 is on the way back to Philip as well. Typical neat but elegant implementation from AP. I've been using a 5v linear supply for USB but the grounds are still common.

It's interesting that it will work on a non-AP USB device that has a separate supply input.

Tom

[jrebman]

Hi Tomm,

Can you do me a small favor and describe how this all goes together -- is the part that plugs into the computer another box like the ap-2 that most likely won't fit behind my mac mini?  Or is it cabled and sits off to the side somewhere?  I was also a bit confused about whether or not you could continue to use your own usb cable, or is there a custom cable harness that connects the ap-2 to the pure power box?

I'm expecting really great things from this with my Metrum Octave.

-- Jim

[TomS]

Hi Tomm,

Can you do me a small favor and describe how this all goes together -- is the part that plugs into the computer another box like the ap-2 that most likely won't fit behind my mac mini?  Or is it cabled and sits off to the side somewhere?  I was also a bit confused about whether or not you could continue to use your own usb cable, or is there a custom cable harness that connects the ap-2 to the pure power box?

I'm expecting really great things from this with my Metrum Octave.

-- Jim

Jim, I am glad to.

The USB from the Mini actually plugs directly into the PurePower VLN box.
There is a provided 12 inch USB A-B cable connecting from the VLN to AP1 or AP2.
There is a provided 18 inch threaded barrel connector cable to connect power from the VLN to AP1 or AP2.
USB is switched in with relays inside the VLN when the AP1 has not seen a signal for awhile to charge the battery pack. When AP1 is playing the USB connections are switched back out except for the processor, OLED, 12v trigger circuit.

Tom

[jrebman]

Thanks Tom -- appreciate it very much.  Guess I'll just have to see how it all goes together once I get it, though I don't see any real problems.  I suppose it won't hurt any that the mini and external fw drive are also on battery power .

-- Jim

[kyrill]

hi
My pure power AP2 is in the " mail" on its way
but is there anybody out there  with more experience now to elaborate more on the differences between  the "old" situation  and he Power update?

[kyrill]

The whole summer and autumn I was frustrated with the AP2 and  its necessary pure power addition , to make it play in JPlays hib + DirectLink. I wondered many times did I do well in selling JKennys wonderful MK3 USB/SPDIF converter?. But Philip was always very responsive and helpful, which resulted in a new driver 1.8 which I have now in its beta version. There is also a new firmware in the pipeline also in beta status.

 

The problems are over. I only had once a hick up but I could not repeat it, so maybe I did  something wrong. With driver 1.8 in pre-release version windows 8 ( have not tried on W7) AP2 plays flawlessly in JPlay hib, DirectLink and Extreme mode with long playlists, all as it should be at least in Redbook format. I have not tried 96khz yet but this may need buffer 2...