[ted_b]

PDX is the actual name and is a DAC from a small Australian developer (some say DIY but bigger than that), but getting great reviews.  W4S stands for Wyred4Sound, a Calif-based manufacturer of amps, preamps (their $2k STP-Se is a giant killer and was my go-to for awhile) and the two DACS called Dac1 and DAC2.  They are known to be leaders in value, with their Class D amps getting great reveiws and their DACs always mentioned in the $1k-$2k category.

[woodsyi]

I am OK with terms of the trade being used although it is always nice when common terms are used whenever they can be.  If I don't understand something then it's time for me to dig in and do some background research to catch up.  It's all fun stuff for us audio geeks.

Carry on gentlemen and I am just waiting in the wings to pounce on a digital front end to emerge in the end that will best my analog sources.  I am going to check out DeBussy this summer in Rockville.  I will definitely have my music on file as well as on disc to check it out. 

[bhobba]

For you guys that aren't up with some of the acronyms for DAC's that have been thrown about the PDX is a DAC made by Lenehan Audio - a small manufacturer on the Gold Coast probably most famous for their ML1 speakers.  Each speaker they make is hand tuned on their reference system which was the system used to check out the DAC's.  The WFS stands for Wyred For Sound and is one of the DAC's people speak about in the $1K-2K price range.  I have this DAC in my system right now, and it is actually quite good, but to my ears it has a slightly cold top end that other DAC's like the Traiquilty and PDX solve.  Here is a link to a review these and other DAC's:
http://www.digitalaudioreview.net.au/index.php/audio-reviews/digital-source-reviews

I was down at the Gold Coast with the owner of the reference system yesterday (Lenehan Audio) with a friend and guess what - the owner of the Audiophilleo2 was kind enough to have left it down there. The Audiophilleo was playing through my level 2 PDX (I had left it down there for that purpose - they are in such short supply even the guy that makes them aren't got one yet).  I thought it sounded very transparent and detailed - to my ears it had a slight grainy quality that I didn't mind since I thought it was probably part and parcel of the extra detail. When we put the transport on it became thinner, less convincing, and less detailed - the bass was less defined as well - but the grainy quality was absent. My friend preferred its absence in the Transport to the Audiophilleo but I preferred the Audiophilleo. Then it was realized the battery power supply was not being used on the Audiophilleo so we switched back to that and engaged the battery - the grainy quality diminished quite a bit and now everyone thought the Audiophilleo was better.

The next thing will be its comparison to a John Kenny I2S built into a PDX.

Thanks
Bill

[JohnR]

Bill, I've had to go up to Coolangatta 3 times this year already... next time I'll have to drop you a line first and see if there's any chance of syncing up, I'd love to hear some of this first-hand.

[Imperial]

What are the effects of the Audiophilleos Signal "transpose" settings?
You know, the "digital cable difference/Rise-time" simulator that I read about on their site when
you connect it directly to the BNC plug on a dac.?
Have you looked into that?

Imp.

[bhobba]

Bill, I've had to go up to Coolangatta 3 times this year already... next time I'll have to drop you a line first and see if there's any chance of syncing up, I'd love to hear some of this first-hand.

Just drop me a line and we can 100% for sure sync up.  I will be more that happy to go down to Lenehan Audio with you where you can hear this stuff first hand.  That goes for anyone else that can make it to Brisbane/Gold Coast here is Aus.

Thanks
Bill

[bhobba]

What are the effects of the Audiophilleos Signal "transpose" settings? You know, the "digital cable difference/Rise-time" simulator that I read about on their site when you connect it directly to the BNC plug on a dac.? Have you looked into that?

Sorry don't know anything about that.

Thanks
Bill

[SolidSqual]

I've been using a Mac Mini Server with a Prism Orpheus DAC for the last several months with absolutely excellent results.  The connection between the server and DAC however is firewire.  This setup was inspired by the glowing review of the DAC in 10Audio.  If you want an amazing piece of digital gear that despite being expensive is actually a steal, then check out the Orpheus.  It's awesome. 

[jkeny]

Hi Bill,
I see you are putting this around on various forums - I certainly am hoping my JK I2S Hiface lives up to the challenge

Whatever wins out on the audition, I believe your headline message is correct - USB audio is now as good as a reference transport & what's more at the higher sampling rates, sounds even better than CD playback (as you would expect)

[TomS]

What are the effects of the Audiophilleos Signal "transpose" settings?
You know, the "digital cable difference/Rise-time" simulator that I read about on their site when
you connect it directly to the BNC plug on a dac.?
Have you looked into that?

Imp.

My Audiophilleo 1 has that "feature" but I've never tried it...

[bhobba]

Hi Guys

Well the comparison has now been done.  I can give you a link to the posts on SNA (Stereo Net Australia) where it was written up but to save you wading through it all I will post a sort of edited cut down version with the main points.

First a post of a person (Kdoot) that was at the comparison to set the scene:

I just got back from an evening spent comparing the AP2 to jkeny's modified HiFace using a PDX. The AP2 was plugged into a BNC socket on the back and going through a Cirrus Logic SPDIF receiver chip which converts to I2S, whereas the modded HiFace provided I2S directly. The AP2 was using my NiMH AA battery pack and the HiFace had a very prototype-quality LiFePO4 battery source.

- on initial listening, all except one person in the room greatly preferred the AP2 to the HiFace, and they really did sound different
- even a Wadia CD spinner via SPDIF was preferred by some over the HiFace, early on
- the HiFace was perceived by most to be "warm", "dark", "lacking energy", "technical"
- the AP2 was perceived by most to be "fuller", "more present", having better "body" and being more engaging

A surprise result, no? But wait, there's more!

We changed amps. Disconnecting the McIntosh 501 monoblocks, we first swapped in my Rega Elicit with the PDX connected to the power amp stage. Suddenly the general consensus swung towards the HiFace, as the Rega presented the sound in a more "musical" way but highlighting the modded HiFace's advantage in detail over the SPDIF-constrained AP2. Then a Trafomatic 8W SET valve amp got a chance to play, and offered up a Diana Krall live recording with absolutely stunning quality. You wouldn't want to throw anything too dynamic at it, but oh my god the HiFace/PDX/Trafomatic/ML3 combination did something magic together.

My personal opinion is that by bypassing the Cirrus receiver chip and all the inherent challenges of SPDIF, the I2S battery-powered internal HiFace delivered a cleaner, more accurate I2S data stream to the DF1704's input. The initial perceived lack of performance was, in my opinion, a problem in the analogue parts of the system - and we seemed to confirm that when we then swapped amps around and found a preferred tonal balance albeit with a compromise in resolution, control and/or dynamic power.

Hopefully there'll be some testing shortly to see whether swapping out the Cirrus SPDIF receiver chip for a TI or Wolfson one gives a boost to the AP2 performance.

Bottom line: the AP2 is still bloody excellent, it's completely simple, tidy, backed by warranty and available "off the shelf". It works with any DAC that has a BNC or RCA SPDIF input and delivers top-quality results. However it's still hampered by the inherent weaknesses in the SPDIF protocol and can be beaten in careful implementations by avoiding SPDIF and going straight to I2S.

Ok now my take.  I agree entirely with the conclusion the AP2 is likely delivering some euphonics due to its SPDIF implementation - it is not in the AP2 but rather the receiver in the DAC.  I beleive the AP2 is rated at 8ps jitter but the receiver chip used is 50ps.  But after hearing the pairing of the Traformatic SET and JK its the JK for me.

Regarding the comparison to a transport we managed to wrangle a Wadia which is the best transport we know of out our way - it even beats the hotted up Marantz that was being used previously.  Some preferred the Wadia - but to my ears the Wadia was left far behind.  I was actually at another comparison with a friend who is getting the PDX with the JK built in and we carefully compared the Wadia and JK. Mike Lenehan explained carefully to my friend what was going on - pointing out the distortion and lack of detail in the Wadia - for example you could hear the foot pedals in the piano with the JK but not the Wadia. After that it was obvious the JK was the winner hands down. However to be fair a couple of very knowledgeable and experienced listeners who did not need any 'hand holding' by someone like Mike still preferred the Wadia. Exactly what is going on there I don't know - other than of course different strokes for different folks - but the majority of people - especially after they have had it explained to them - preferred the JK. 

Thanks
Bill

[jkeny]

Bill,
There's no doubt that these two devices are both achieving high levels of performance & can now compete with some of the best CD playback sources.

I didn't ask this on SNA but I'll ask it here - I presume you were comparing files stored in 16/44 format Vs CD playback via the Marantz? Did you listen to high-res files? These should easily surpass CD playback

[jkeny]

TomS,
I meant to ask you two things:
- what improvement did you notice in using an external 5V supply on the AP1?
- Did you ever try the jitterSimulator & how would you describe the sound of th extra jitter?

One thing I've been suggesting for a while now is to use RF attenuators on SPDIF devices. I suggested on SNA is to try an RF attenuator on the AP2. I (& lots of others) have found that these devices work to reduce any digital glare - it is thought by reducing reflections. Sometimes, we don't even notice this until it's gone. There's a good write-up on the technical aspects of these on this forum http://www.audiocircle.com/index.php?topic=90454.0

[TomS]

TomS,
I meant to ask you two things:
- what improvement did you notice in using an external 5V supply on the AP1?
- Did you ever try the jitterSimulator & how would you describe the sound of th extra jitter?

One thing I've been suggesting for a while now is to use RF attenuators on SPDIF devices. I suggested on SNA is to try an RF attenuator on the AP2. I (& lots of others) have found that these devices work to reduce any digital glare - it is thought by reducing reflections. Sometimes, we don't even notice this until it's gone. There's a good write-up on the technical aspects of these on this forum http://www.audiocircle.com/index.php?topic=90454.0

Actually, it depends. I have a dual linear supply, with 12v feeding the Alix (USB source). The Alix then provides the 5v to the USB bus through a little onboard switcher. With the Alix and a wall wart and stock 5v switcher there is a bit of an edge though I wouldn't go so far to call it glare. I used the wall wart and a linear 5v to the AP1 only very briefly and it eliminated some of that. With a clean linear to the Alix it doesn't really matter whether I use the switcher from the Alix or the isolated 5v linear to the AP1. Sound is great, not a hint of edge/glare at all (either way), so I don't use the 5v linear at all now. The linear supply on the Alix itself had the most impact in my system so it has stayed. The other variable there is I have a Wireworld USB cable that goes direct from the Alix to AP1 when using the switcher, so nothing fancy, but the cable is not broken in the middle and going through 2 extra USB connections and a second USB cable in series as it is with the linear 5v supply. I'm sure that has some impact but I wasn't inclined to just hack up the WW cable to find out.

Sorry, I have not tried the jitter simulator and cable length settings at all. I'm more inclined to listen to music than go through all the tweakable permutations for sport. Just doesn't interest me much as it will only degrade the sound.

I've actually read quite a bit about the attenuators and haven't gone that route after talking with Philip about it at length. I suspect I am lucky enough to have a near ideal match of the AP1 and the Bryston BDA-1 receiver input and cable such that S/PDIF "error" is having little or no influence on the sound. No real way to tell in a comparative sense, but it sounds very good to me. Of course, other situations and results may be totally different as Bill's listening group discovered.

[jkeny]

TomS, I don't really follow the permutations of you PS but it's late here so I'll read it tomorrow.

I was just suggesting the JitterSimulator to get a handle on what some jitter sounds like - as a service to readers

I wouldn't dismiss the RF attenuators - for $20 they're worth it.

I hear what you're saying about listening to music though & forgetting about all this tweakin

[bhobba]

There's no doubt that these two devices are both achieving high levels of performance & can now compete with some of the best CD playback sources.  I didn't ask this on SNA but I'll ask it here - I presume you were comparing files stored in 16/44 format Vs CD playback via the Marantz? Did you listen to high-res files? These should easily surpass CD playback

Good question and we did.  We played Ella and Louis in Hi Res and down-sampled to regular 44.1/16.  This is one of the first times I heard a difference in favor of the Hi Res - not much mind you - but it was there.

Thanks
Bill

[jkeny]

Good question and we did.  We played Ella and Louis in Hi Res and down-sampled to regular 44.1/16.  This is one of the first times I heard a difference in favor of the Hi Res - not much mind you - but it was there.

Thanks
Bill

Was the Ella & Louis a true high-res recording & not just a 16/44 upsampled? Too many of these recordings being sold as high-res have been shown, on analysis, to have a sharp cut-off at 20KHz - signifying a brickwall filter!

The reason I ask is because I notice a significant difference with true high-res material but I haven't down-sampled it to 16/44

[bhobba]

Was the Ella & Louis a true high-res recording & not just a 16/44 upsampled? Too many of these recordings being sold as high-res have been shown, on analysis, to have a sharp cut-off at 20KHz - signifying a brickwall filter! The reason I ask is because I notice a significant difference with true high-res material but I haven't down-sampled it to 16/44

To the best of my knowledge it was true Hi Rez and the difference was more than I notice with up-sampled stuff - I use up-sampling all the time and know well what it does.  Yes it was better - night and day better - no - but better for sure. 

Thanks
Bill

[bhobba]

Hi Guys.

Mike Lenehan just completed the results of his evaluation - the John Kenny won out.  His write-up will be attached at the and of the post.

Thanks
Bill

Hi All I have just finished over 9hours of comparitive listening using the standard Mac Mini with standard USB cable as source into the following Audiophilleo2 ! Audiophilleo2 battery powered by 4 of 1.2volt NiMH ! KennyHiFace direct to I2S. ! Wadia WT3200 CD Transport.

We all conducted the initial comparative listen on Friday night using ML3Reference which were fitted with Mundorf Silver oil capacitors which were brand new ! (Silver oils don't sound good when their new they need to be hit pretty hard for about 3 to 400hours before that they produce a strange combination of sweetened presence range and lower treble coarseness ! some people love the sound and get hooked on it then when they run in and improve many audiophiles have changed their system sufficiently to not notice.) In any case I swapped to ML1Reference and Tunestands which were in a run in and more neutral state.

I would liken the results ! and in this order to be just like walking up a flight of stairs . first step MarantzCD95 disc transport ! Wadia WT3200 disc transport ! Audiophilleo2 ! Audiophilleo2 Battery ! JKennyHiFace I2S.
For SPIDF input comparisons we can only compare directly the disc spinning transports with the Audiophilleo2 which also ran on the same CS8416 reciever chip . (more on another higher performing reciever chip from Clay Geisler the PDX designer in the form of an attachment at the bottom of this post)

The CD95 was just wonderfull untill I heard the AP2 (remember both on SPDIF) lay down mezzere I'm afraid ! the smoothness, resolution and bass articulation of the AP2 made me question why I loved the CD95. The Wadia WT3200 closed the gap about one third of the way toward the AP2 but still had saw tooth distortion on the leading edge of heavily struck middle C and above piano notes. Bass from the disc spinners is to my mind indistinct slow and just unable to keep up with the signal. Vocals also seem to have a mild ragged bloom to them (could we just use a larger countershaft sprocket and spin the disc at higher RPM ? silly Joke )

The AP2 on batteries sounds a tad faster and more tactile ! less bloomy if you like ( sometimes that bloom sounds goooooood though !! is this a touch of jitter being sent down the USB cable on the non battery powered AP2 doing this ? )

The JKenny Hiace on I2S rules ! I'm saying this not so much because of the comparo on Friday night where we were using the Mundorf Silver Oil equipped ML3Reference(the new Silver Oils were slightly skewing results) but because over the next two days with the Duelund equipped ML1's the I2S device showed it's true character !! in other words None !! No bloom no lean mids no slow bass just JUST music. This new technology is just what my ref system requires because it is neutral NEUTRAL with a capital N You will of course be required to set your system up so it has even less glitches than before ! less leeway for errors brothers ! With these new source devices the audio world is your oyster just dont cut yourself whilst shucking. This new experience may be like jumping out of a hot

I hope we don't start getting posts like ! I don't like accurate sound it's too clinical for me ! or I prefer a more tonally fleshed out mid or a bit more bass. I've always believed in making an audio system sound as much as possible like live unamplified acoustic instruments and vocals not the way I may have subjectively prefered the sound at any given time. Kdoot pointed out to me on friday night that I had said to him last year that I tune a system to sound like real live music and not nessessarily something that is true to the source ! I guess thats true ! but then last year the source was not up to it in many ways and perhaps ! just perhaps ! I saw no other options at that time. Well I'm here to tell you fellow OCD's that paradigms have changed. Best Regards Mike Lenehan
LenehanAudio

[TONEPUB]

That Wadia you are mentioning is ancient....  Not a terribly valid comparison.