Sony HAP-Z1ES Hi-Res source (new 2014) ?

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Additional High Resolution HDD Audio Player in same Sound Quality wanted

This seems to be one of the best HDD Player. A test review and measuring results are here
Sony HAP-Z1ES high-resolution file player | Stereophile.com

I am looking for more cost effective solutions with same ore nearly same sonic quality results. Important is the support of all high resolution Audio formats (like this Sony HDD audio player) and a low-jitter master clock.
Not necessary is an integrated HDD and an integrated dac, because there are a great amount of dac's on the marked. HDD docking stations like the devices under
FANTEC GmbH - HDD Docking Stations
are also good available.
OTOH - operation instructions should be possible without app's for PC's and smart phones - this means, it must be possible for an independent resp. self-sufficient operation without PC; i. e. display and RC transmitter should be present.

Are there devices in this kind on the marked?

Thanks for advices.
 
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I own a Sony HAP-Z1ES, and am not aware of anything as slick at anywhere near the price - does not mean you could not build something similar I suppose using the lastest version of the Raspberry Pi..

Or you could wait for one to show up used, the toy boys will soon grow tired of it and sell it on as part of the never ending quest for sonic nirvana.

I bought mine with the idea that I would eventually modify it, however as I got to know it over the past eight months or so my motivation waned drastically; it is very, very good.
 
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My thoughts (part 1!)

I just picked one of these up used on EBay for just over $1200 shipped. Music from the previous owner was still on it, so I even got some new music!

I've read the reviews and threads spread across the web and had it in and out of my smaller system a few times. So far, I am sufficiently impressed to strongly consider keeping it, but not so impressed that I will keep it stock.

I'm coming from a DIY'd all-in-one box using an extreme-minimized cMP/cPlay load (<15Mb for the OpSys & player software) coupled to a super-modified ESI Juli@ and an I2S-connected EUVL ES9022 DAC card. It's running an extreme-fanatic set of linear supplies including for the computer ATX/P4. Music is on an SSD and control is via an IR remote that feeds an IR-connected keyboard dongle... very convenient, it lets me control the beast with little fuss. I don't mind the hair-shirtedness of it, some of my previous digital source have included a modified PS-1 (no display, no more functionality than a turntable with the ability to skip forward and back) and a Shigaclone (similar to the PS-1, but track numbers were displayed).

All of my music is ripped from CDs, all of which I still have. I don't need have album artwork displayed or use any web-based streaming services. And I want the best sound I can achieve given my equipment and ability to modify/tweak it, so generally I shut off things like wired or wireless networking anyway.

One really nice function of the cMP/cPlay software is a good built-in volume control that sonically is very transparent... It is sonically better than my broadcast-quality passive stepped attenuator using a shunt configuration with a Vishay nude series resistor and Vishay shunt resistors. I will truly miss that with the Sony

My thoughts...

1. Usability/Functionality is pretty good. The lack of a good built-in volume control is a drawback for me, this may push me to look at remote-control volume options for that system. Also the more common 'playlist'-based setup loses some of the functionality of my cMP/cPlay setup which uses 'Cue' files. These allow me to have a recording in a single physical file yet still be able to skip forward and back through tracks. The HAPZ DOES provide fast-forward/backward via the remote, which I can use in a pinch. But compared to my cMP/cPlay setup, it is definitely a step backward and will require some adjustments like potentially upgrading my attenuator for remote and getting used to not having track-select ability on most of my already ripped music (and I REALLY don't want to re-rip!).

2. Sonically it is also pretty good. Highs are more clear and transparent than my cMP setup. Bass is similar, with the HAPZ clearer in some regions and the cMP in others. The HAPZ wins very slightly on midrange clarity, but the cMP wins definitely on listenability in my system. I find the HAPZ exhibits a bit of 'digital-itus' compared to the cMP and the HAPZ is slightly fatiguing to listen to over time. Still, the good aspects of the HAPZ sound hold a lot of promise. The engineers spent a LOT of effort designing good sound into the unit with a highly rigid and fairly non-resonant case and completely separate digital (processor, storage drive, connectivity, DSP) versus analog (clocks, DAC, output stages) power supplies all the way back to separate transformers. One nice touch is the use of SMD film caps (PPS or Acrylic, not sure which) around the DACs and output stages.

3. Getting music onto it is not as much of a problem for me as others have observed. I just take the drive out of the unit and use a separate Linux computer to transfer music onto it. So the slow transfers encountered using the networking functionality are completely sidestepped.


Kevin, I am very interested in what you had considered for mods to the unit. I spent a lot of time going over the thread by Vinnie Rossi on the AudioCircle site and what he decided to do with mods. Based on my experiences building up my current music server over the years and what he considered and does, here's what I'm planning (see part 2)...


Greg in Mississippi
 
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And now part 2...

... Here's what I'm planning:

Phase I

- Quiet the structure with surface damping of the case.

- Disconnect the power to the USB/Ethernet board, fan board, and Wifi/Bluetooth board (I've confirmed it functions ok with the power disconnected to the first 2 so far).

- Separate the AC into a dirty AC feed (digital side) and a clean AC feed (Clocks, DAC, and output stages) with seperate power cords going into different filtering regimes I already have in my setup (this is a standard part of the cMP/cPlay hardware setup)

- replace the harddrive with an SSD

- Directly connect from the output stages to hard-wired jacks using upgraded coupling caps (likely Auricaps for now, something better later if I don't come up with a solution that does not require coupling caps).



Phase II

- Rebuild/upgrade the power supply boards using better diodes, Jensen 4-Pole caps (and completely bypassing/replacing the DC-to-DC converters on the digital PS board). This will take some careful planning to retain the power sequencing and muting functions, but my initial look at the schematics suggest it is quite doable. Regulator locations for the Clocks / DAC / output stages lines will be moved from the PS boards to the output board.



Phase III

- Try some alternative I/V & output stages, such as the OPA1632 as used by Twisted Pear in their Ivy I/V stage which would allow a single-stage balanced output from I/V to output stage. Also looking at options like the OPC D1 stage, the TP Legato, and EUVL's SEN/CEN stages. Another alternative would be to retain the current I/V stages, but use a good tube stage (Unbalancer?) afterwards.



Later I might look at an adapter board to take the I2S feed from the processor/DSP & feed it to a different clock / DAC setup.


One thing that I could use assistance on is suggestions on how to identify some of the connectors, this is something I've never grappled with before. Most of the mods I have planned above will be a LOT easier if I can build them up using separate connecting cables instead of splicing into the existing ones. This would also allow me to keep much of it stock through Phase II... if I'm not pretty happy with it by that time, I could still restore it to stock and re-sell it.

I do plan to look at buying cables (and boards if appropriate) from spares vendors, but my experience is that these will be EXTREMELY expensive for what they are, hence my interest in getting replacement connectors from the typical vendors. I DO have the service manual (downloadable online from the usual suspects, just Google it), but I've not found sufficient info there to positively identify the connectors.

Thoughts on all of this? Kevin, any suggestions based on what you originally considered doing to the beast? And can anyone provide suggestions on how best to track down the connectors? And anyone else planned or have executed any mods to the Sony?


Greg in Mississippi
 
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So far VERY GOOD!

After a lot more study and thought on what I posted above, I spent much of the last three weeks digging into my HAPZ.

As typical, I haven't followed my plan as above. Part of that is laziness and doing what can be done fairly easily, part of that is better understanding the unit and its parts as I've gotten more familiar with it, and part of that is seeing what has worked well and trying to identify what else will work well.

Here's what I've done...

This first group was largely an attempt to lower digital processing-induced noise, focusing on easy hits:

1. Replaced harddrive with an SSD, with damping on the SSD and mounting (Dynamat Xtreme).

2. Disconnected the cables to the USB / Ethernet / Remote board and the Wifi boards (Note I am using it as a standalone player only, I only connect it to the network to get firmware updates).

3. Disconnected the cables to the fan and pulled the fan and mounting bracket.

4. Add a 2nd AC line relay and IEC to provide a 2nd AC feed to the analog supply transformer. As I mentioned before, I have two seperate AC paths, one for 'noisy' digital circuits with in-line filtering, the other for quieter circuits with some parallel filtering and passing though a PS Audio P10 regenerator. The digital / standby transformers AC cord would plug into the 'noisy' AC path, the analog one into the quieter path.

I really heard very little difference with these changes, only a slight reduction in the 'digital-ish' sound. That was puzzling, but I have an thought below as to why.


The next group of changes was to improve the analog signal path. After going through the service manual more, I realized the filtering caps in the output stages were mylar and the resistors carbon. Also, I didn't see any reason to think the coupling caps were very good choices. And I didn't like the plug-in cabling from the main analog board to the single ended RCA jacks board. So I:

6. Replaced all of the output stage resistors in the SE path from the I/V stage to the output with 1/2w PRPs.

7. Replaced all of the filtering caps in that same path with Wima polyprops.

8. Replaced the SE output coupling caps with non-polar Black Gate 33uf N series.

I'll do the balanced R's & C's at some future time.

I heard a larger change here, but nothing like I expected. Sweeter, a bit more detail, not much more. Also puzzling, but a good step forward.


Next I wanted to improve the power supplies. I decided to start with the digital supply board as it was the easier one to tackle. What I did here was:

9. Replace the 2 main raw DC filter caps with larger Nichicon KG series caps while pulling the 6 remaining DC-DC converter-related caps off those boards.

10. Bypassed the three DC-to-DC converters by removing the + output leg of the diode bridges and wiring that to the + leg of the above capacitors off the circuit board. By doing this and moving the output cables from the board to the output of the added linear regulators, the DC-DC converters are completely out of the circuit.

11. Wired in two linear regulators, both using LT3080s, with one for the SSD 5v right on the SSD power connector (with a small heatsink) and two in parallel for the main 5v on a medium-sized heatsink placed on top of the three DC-DC converters.

12. Kept the turn-on sequencing by wiring in the STBY 5v and STBY POWER lines into the new main 5v regulator. This required cutting two traces on the board (which can be easily bridged to restore it to stock).

13. Retained the 5v USB power with a small plug connection at the SSD regulator. Unless I plan to use the USB and plug that board back in, this stays disconnected.

This change was a huge improvement, a revelation, a MUST DO, reducing the overall noise floor, increasing dynamics, sonic purity, naturalness, and detailing. After hearing this, I realized that why my earlier 'digital noise reduction' changes didn't make much of a difference was that the DC-DC converters must be putting enough noise into the system that it swamps the noise added by the HDD, USB, Ethernet, and WiFI. I suspect if I had done this first and then done steps 1-4, I would have heard a larger difference after doing them.

IF ONE IS CONSIDERING ANY MODIFICATIONS TO THEIR HAPZ, THIS IS A MUST AND WHERE TO START!!!


Stopping here is not a bad place, the improvement was so marked. But armed with this success, I went onto upgrading the analog power supplies. My strategy here was to move the regulators from the analog PS board to the rail feed points on the analog board to reduce the effects of the intervening cabling. But while deciding how do this, I noticed that the base current draw on the +-15v regs was 40mA, but jumped to nearly 80mA when the mute relays were energized. Since those don't impact sound quality and driving them from my upgrade regulators would push those reg's limits, I decided to keep the stock regulators for the relays and separated the feeds to the relays from the output OpAmp +-15v lines.

To do all this I:

14. Replaced the analog board 4 main raw DC filter caps with larger Nichicon KG and Fine Gold caps.

15. Pulled the regulators and caps for the 3.3v Clock and 5v DAC supplies off that board, but retained those for the +-15v for driving the relays.

16. Cut the lines on the analog board to the relays just outside of the +-15v filter caps on the analog boards and wired from the stock regs on the analog PSU board to those lines. There were a couple other small changes needed here, I can detail if people are interested.

17. Wired in new regs for the +-15v output stage supplies, Clock 3.3v, and DAC 5v and 3.3v onto analog board. I inserted them either at the connectors or at the filter caps on the analog board for each rail. Each of these analog board-side regulators had a pre-regulator and post-regulator filter cap mounted onto the regulator as an assembly. I also removed the on-board DAC 3.3v regulator (a very small SMD regulator chip) in favor of my add-on regular. The 2x 3.3v and 5v regulators were AKR75s from AckoDAC, the +-15v regulators were a small proprietary shunt regulator from a friend at one of the modification houses, but one could use Dexa, Belleson, Sparkos Lab, or Hynes units here to very good effect.

18. Replaced all of the other PS filter caps around the DACs and Clocks with larger Nichicon Muse.

19. Either stacked 1uf Panasonic SMD PPS caps on top of the .1uf SMD film (likely PPS, but possibly mylar) caps already around the DACs and OpAmps or added them on the nearby rail traces.

This also set of upgrades was also a huge improvement and a revelation. But I suspect it would not have been as marked without replacing the DC-DC converters above.


With all of these changes, to my ears the HAPZ is much improved with vanishingly low 'digital-ish' sound and greatly improved detailing and dynamics.

I have a few other things I plan to try, but it is so good right now I have no motivation to do so!

I know I have not provided any details here and no pictures. I will post more on this, but only if anyone is interested.

These provided a large performance lift to the unit, but realize they of course:

1. Void your warranty.

2. Must be done at your own risk.

3. Must be done by you only after you have studied the circuit and setup using the service manual and you understand what you are doing.

4. Could potentially kill your expensive HAPZ if you do anything wrong.

These are modifications only for experienced techs/modders!

Greg in Mississippi
 
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Thanks for sharing what is a very comprehensive list of mods. I'm still pretty happy with mine, but do find it can sound a bit digital in straight PCM mode, but I always run mine in DSD mode which makes a pretty big difference.

I've not made any modifications other than some minor damping to the chassis to tame that transformer buzz. Eventually I will add some further damping to the chassis.

I was considering PSU upgrades, and hard wiring in place of those cheap audio connectors you mentioned.

I also thought about getting rid of some electrolytics and upgrading some passives in the signal path.. (From experience it seems that Sony uses fairly good resistors in the audio path, I wasted a lot of money replacing the stock Rikens with Caddocks with no appreciable gain in my 777)

I've heard that getting rid of the dc to dc converters is a big win.

Did you get the service manual online (sony service?) or elsewhere - last time I checked it was not available, but it has been a while.
 
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Kevin,

Very welcome. And yes, if you do anything, replace the DC-DC converters first!

On DSD versus basic PCM versus Precision PCM, to my ear and in my setup I've always preferred PCM to DSD. That surprised me. Stock, I preferred basic PCM. Modified I prefer Precision PCM. Both sound more impactive and transients are 'harder'. Not sure if that is more like real, though. OTOH, with these mods, I do like DSD much more, just still prefer PCM.

I did (and did again tonight) find the service manual online at the usual free download sites with a Google search. OTOH, I can email it to you if you want, just PM me with your email.

I'm not sure what carbon Rs they use in the HAPZ. Def not the blue Riken I'm used to. Neither do they look like either Shinkoh tants or Takman carbons. OTOH, I don't think that's a really high-value mod, not in the same universe as the PS mods and likely not as significant as replacing the mylar filtering caps and electrolytic couplers with polyprops.

I hope to know more about that in the next week or so, I'm putting together a balanced attenuator and will listen to that path, where I've not upgraded the Rs and Cs. Of course, there are other components than the resistors there, but I should be able to get at least some impressions.

One thing I didn't mention is that I expect there is another significant improvement opportunity available. The I2S feed is direct from the FPGA. They did well in that the clocks are local to the DACs, but the I2S feed traverses at least 12" or more. Adding an interface board (like Acko's S03, but with more isolated lines and adapted for the HAPZ's connections and form factor) with post-isolation reclocking of the I2S signals is now a high-end best practice that I was surprised they left out. I expect doing that and breaking the ground connections between the processor/DSP/controls/screen side and the DAC/clocks/analog side could be very significant.

Need anything else, let me know.

Greg in Mississippi
 
Hi Greg
What an amazing report... very very interesting
My Sony is still full stock.
i would be very very interested to get a IS2 output to be able to use another DAC...
is that doable do you think ? i do have the service manual already , say the output of the FPGA etc....
anyway to add a digital out without compromising too much the quality of the Sony ?
thanks for your help !:D

Pw8888
 
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Hi Greg
What an amazing report... very very interesting
My Sony is still full stock.
i would be very very interested to get a IS2 output to be able to use another DAC...
is that doable do you think ? i do have the service manual already , say the output of the FPGA etc....
anyway to add a digital out without compromising too much the quality of the Sony ?
thanks for your help !:D

Pw8888

You can, but it is not a simple thing.

First, as I mentioned above, Sony has the audio clocks on the audio board and these are fed back to the FPGA/DSP and used in generating the I2S signal. Going over the lines from the FPGA/DSP/Processor section, it looks as though all of the lines flow from that section to the Analog board EXCEPT the clock. So you have to keep AT LEAST the clock feed to the FPGA/DSP AND the control line from the FPGA/DSP that signals which clock (22Mhz or 24Mhz) is needed. Without these, the I2S signal generation process doesn't function.

Easiest ways to keep the clock generation process alive is to either retain the existing Analog board, but un-power/otherwise disable the existing DAC and output stages OR develop an isolated interface/clock generation/reclocking board as I mention above. This second option would be cleaner, potentially better, and more flexible, but takes someone who can design and debug that board... and sorry, I am not that person.

Then you need to consider what type of DAC you might use. Easiest would be a small-ish DAC card that can fit in the case. You could feed it the I2S lines and clock (if needed) from one of the two clock generation solutions above.

If you wanted to use a DAC outside the case, your best bet would be to use an LVDS interface (like the Twisted Pear Transporters) to carry the I2S lines and then reclock it before feeding to the DAC with something like Ian's FIFO. Of course, this can all be fit into the case too, if you are clever.

What you likely can't do is just take the I2S feed off the FPGA/DSP board and carry it over to a DAC... very tiny lines and pads to solder to, best to use the existing flat cable interface... and to use that you need some sort of interface board anyway.

It would also be difficult to add external I2S lines AND keep the existing DAC functioning. Again, you'd need an interface board of some sort. The BEST solution here is an isolated interface/clock generation/reclocking board and include a 2nd I2S takeoff (possibly into an LVDS interface) before the reclocking and use the reclocked I2S signal to feed the internal DACs. That could be done with no penalty to the current setup's sound and likely a significant improvement due to the isolation and reclocking.

Sorry, it doesn't have a simple solution! And none of these will be cheap either!

Greg in Mississippi
 
What flavor DC-DC converters in the HAPZ? TI has a couple of papers discussing noise minimization.

I should put the LT3080 through its paces for PSRR, noise, Zout and THD. I can suggest that the LT1963A is about the best sounding OEM regulator, teamed up with its LT3015 negative cousin.

(Wifey gave me the HAPZ for Christmas).
 
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Great present, Jack! What a wife!

The DC-DC converters in the Digital Supply Board are RT7256ALZSP. It looks like a proprietary Sony chip. Curious to see what you come up with. If you haven't gotten the service manual, let me know via PM & I'll email it to you so you can see the circuit as-designed

I'm very curious what you find comparing the LT3080 to the LT1963A. The latter looks like a great sub for the DC-DC converters too. I have to say that to my un-educated eyes, comparing the performance data from their datasheets suggested a slight edge to the LT1963A, but not by much. And to be clear, I only used the LT3080 because I had some built-up from earlier projects. It has been a clear upgrade from LT1084/LT1085s for me in the past, but I am sure there are better options available.

I am considering replacing those regs already anyway. I need to first see what the current draw of the processor/DSP/screen set are (I say it that way, but that really oversimplifies it... there are a number of control/signal generation components powered by that 5v rail). I'm looking for something with a much lower dropout, of which the LT1963A is a good candidate, as is OPC's LT3042 paralleled regulator board. I'm considering battery powering this side as the first step towards fully isolating the deep digital sections from the Clocks/DAC/Analog sections, inspired by Barrows' battery powered computer music server described here:

"New" LiFePO4 Powered Server

I'm considering using 2 2-cell LiFePo4 packs, one for the SSD, the other for the main 5v, but the almost 1.5v dropout of the LT3080 will severely limit the amount of available capacity that can be used out of the packs. The <.5v dropout of the LT1963A or the LT3042 would work well there... especially the LT1963A as it has several protection features that appear to be designed with a battery-powered setup in mind.

Back to noise reduction, I am a big advocate of not creating noise in the first place as any noise reduction efforts will not be perfect. That drove my unplugging a number of sections that I just don't use or won't use often (I can always open it up and plug them back in if needed) just as it did my replacement of the DC-DC converters on the main Digital Supply Board. OTOH, there are at least 4 other DC-DC converters on the various processor/DSP/screen board and almost 2x that many additional local regulators. I don't intend to touch any of those, those boards are very tightly packed AND I suspect there are some critical start-up timings that need to be observed.

Again, very curious to hear what you see when you compare, Jack.

Greg in Mississippi
 
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Kevin,

Sure. A few caveats, tho...

1. I didn't take any pictures while I was doing the mods as I typically do. I had a 2 1/2 week period where I could work on this to my heart's content (my wife was visiting her family far away) and it of course, took longer to mod than I expected. So no in-process pix.

2. In that case, I'll take some pictures as best as I can now. But not much is really visible, with some connections under the new main filter caps and the heatsink covering most of the digital supply board.

3. And it is ugly! I don't do pretty mods or builds! Actually, that is not entirely true, my circuit boards look very nice, until I implement them into my ugly builds! OTOH, this uses a couple of point-to-point regulators that I built up... double-plus ugly!

So I'll take pictures as best as I can. AND I'll write a quick step-by-step. And if you don't have the service manual on hand, please let me send you a copy... it will make much more sense with that in hand.

AND it really is a pretty simple mod. One doesn't have to do much to take the DC-DC converters out of the circuit. It should work with most small regulator boards. And two small reversible trace cuts and two short connecting leads are all that are required to retain the turn-on sequencing. Oh, and you can keep the fan drive if you want with a 3rd regulator... that will take a bit of work to integrate the on/off and 2-speed switching functions, but nothing too complex there either... a single fan enable line and a single speed select line have to be integrated into the fan drive regulator.

I'll be taking my HAPZ out of the system later this weekend to check the digital 5v main current draw and try a couple more small things. I'll take the pictures then.

Greg in Mississippi
 
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I have the service manual, just trying to determine whether I currently have the manual coordination to do the required mods or should wait a little longer. Not worried about the mess or even step by step - just an idea of what I would be getting myself in for were I to proceed down this road.

I use the wifi so that is one option I can't do without, hopefully that does not render the rest pointless.
 
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Thanks for clarifying that Kevin.

I did get a chance to both take pictures AND measure the current requirements of the main 5v, both with the cabling to the I/O Board (USB & Ethernet) and WiFi disconnected (as this is how I run the unit) AND with them connected (as this is how I suspect most everyone else will run the unit).

With those boards unplugged I saw about 3mA draw with the unit plugged in, but off (important to know if one desires to use batteries to power that section), and about 600mA running (rough average) with short peaks of near 1A. Running the same check with those boards plugged in added 50mA-100mA, with the peaks hitting 1A. So Jackinnj's LT1963A would be a good choice, but remember to heatsink for the fairly high voltage drop from 13.4v-13.7v (I didn't at first and saw 70C on my regulator heatsink tabs!).

I'll organize the pictures and do a quick writeup tomorrow or Tuesday.

Oh, and I don't think using the WiFi will matter much, both from the perspective of benefits to replacing the DC-DC converters and current draw (as seen above, but different WiFi environments will likely change the current draw). I do know mine connected while I was checking the current draw as it started updating my database!

If you want to use WiFi and want to minimize the potential any impact of the associated RFI, you could keep the WiFi board disconnected as I do, but use a WiFi extender or access point connected to the unit via a 3'-6' cable to the Ethernet port (of course that board would have to be plugged in for this to work). That was a trick used by tweaky Squeezebox Touch users who noticed a significant sound quality hit using the in-board WiFi function, but needed the network to get their music and did not have a nearby wired LAN connection. See here for one account:

soundcheck's - audio@vise: Touch Toolbox 3.0 - HW and Network

Greg in Mississippi
 
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Yes, it is an expensive box, and I paid full retail for mine. (My phono cartridges all cost more than the HAP so I had to get used to the idea of an "accident" taking out one of these, so I am not too risk adverse.) I do feel there is some room for improvement, but I am pretty happy with the basic performance. I have heard better, but not for the kind of money I am willing to pay.

My system is all tube based with transformer coupling in a lot of places, room equalization and bi-radial horn mids and tweets with Onken bass bins. I run in DSD mode as I find straight PCM a bit hard and edgy sounding in my system, and the MF/HF sections have so much snap already that the edge was not a positive.

Damping the mechanical buzz from those power transformers would be a major improvement, they are well above the room and electronics noise floor even with my very efficient speaker system.
 
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