Audiophilleo 1 and 2 USB to S/PDIF transport - Page 50

My transport is based on the original Hiface 1, but still would be interesting to see if the new hiface uses a hardware buffer.

Quote:

Originally Posted by drez 

^ Very interesting, I think I have seen a couple of DAC's that use internal hardware buffer, but this seems to be more common in the very expensive models.  Audiophilleo certainly seems to be ahead in terms of hardware and measured performance - I would certainly like to compare one to my modified Hiface with ultra short USB cable.  Only problem is I feel compelled to save for the full-blown purepower package rather than buying the standard AP2 and upgrading later.  Still would be interesting to compare a stock AP2 purely for a perspective of price/performance between the units.

 

You may be right in that the HiFace uses software buffer rather than hardware.  If one has a look at the PCB one may be able to notice the presence or absence of memory - or I could email HiFace to ask - but either way I'm sure the hardware is not nearly as powerful as the Audiophilleo and is several years old.

I have never quite understood why more DACs don't use an internal buffer.

There are only two drawbacks to having a buffer in the DAC:

1) The buffer will necessarily introduce delay. Since the data is arriving at the DAC at a fixed rate controlled by something else (with all except asynch USB), the buffer has to be big enough that it can store enough data that it won't run out if the source clock is running a tiny bit slower than the DAC's clock. (With asynch USB, or the buffer inside a CD player, the buffer can "call for" more data is it runs low...) Since you have to fill the buffer before you start playing, there will have to be a delay before you start playing equal to the size of the buffer - but we're only talking about a few seconds delay on each track.

2) Obviously, if you have a buffer in the DAC, then the DAC has to have its own clock; and, if the DAC supports multiple sample rates, it will have to be able to recognize which clock to use, and then have a clock available at each sample rate it needs.

The benefits, however, are huge. Quite simply, if you have a buffer, and your own clock, then you are TOTALLY immune to jitter. Since you're entirely discarding the original clock, the only jitter you're going to have is the jitter that your own clock has - which is under your control and will be source-independent.

The first issue (delay) would be a big deal for a recording studio, where you need to time-match things, but shouldn't matter at all to an audiophile.

ok, I'm an idiot.  I've long been ignoring these products but I just decided to try them out.  I almost ordered the ap2 with pure power until I realized I was looking for a COAX reclocker but the AP doesn't take a COAX input.

I use my OPPO as my media controller so I guess this is out.
 

Quote:

Originally Posted by tme110 

ok, I'm an idiot.  I've long been ignoring these products but I just decided to try them out.  I almost ordered the ap2 with pure power until I realized I was looking for a COAX reclocker but the AP doesn't take a COAX input.

 

I use my OPPO as my media controller so I guess this is out.
 

Empirical's Synchro Mesh will do that for $599. No need for a battery supply either.

http://www.6moons.com/audioreviews/empirical4/1.html

Any updates from AP owners who have gotten the Pure Power modification?

Quote:

Originally Posted by DaveBSC 

Empirical's Synchro Mesh will do that for $599. No need for a battery supply either.

 

http://www.6moons.com/audioreviews/empirical4/1.html

yea, there's a couple 'converters' that will do it but that's a new one so I'll check it out.

My PurePower just came in today. It might take me a day or two to be able to get a good listening session in, but here is a picture of it installed. It's the blue box next to my DAC. You can see it connecting to the AP2 directly.

Quote:

Originally Posted by Sid-Fi 

The PurePower is an awesome little unit. It feels really substantial and durable with a great chassis and nice fit and finish. As others have reported here, it's a notable step up from the AQVOX (which was in itself a nice improvement over AP2 stock). Coming straight from the AP1/2 to the PurePower would seem like an awesome improvement without having had the Aqvox in between.
The additional improvements are similar to those the AQVOX brought, only better. I am getting a very black background, effortless low level detail, and an organic/musical touch that adds much more of an immersive experience to my ears. Compared to my setup sounding awful while the AP2 was away getting modded, it sounds glorious right now.
I'll have to post my AQVOX in the for sale forums tomorrow and save some lucky chap an arm and a leg in shipping from Germany. It cost me $75 to ship the dumb thing from Germany this last Christmas :0.

Have you tried the purepower with and without the aqvox?  I am interested if there is a difference as from my understanding purepower powers the clocks and SPDIF output but not the USB receiver, probably for a good reason but still would be interesting to see if there is a difference.

I think I will buy Purepower and AP2 once I sell my NFB-10 SE - transients in my system are still not quite clean enough as it is.  Empirical Audio will soon have an interesting device that sorts out computer ground related issues, might be a good alternative to galvanic isolation.