[Vinnie R.]

Vinnie, forgive me if this is an ignorant question. Aren't the Dual Burr Brown PCM1795 d/a chips only used for playback of PCM material in PCM, not for PCM converted to DSD?

This is not correct.  The dual PCM1795 d/a chips handle BOTH the PCM and DSD conversion.

Here is a simplified block diagram (not showing power supplies):

HDD (Hard drive with your music) >> MCU (microcontroller)  >> FPGA >> PCM1795's >> Analog output stage

Also going in/out of the FPGA is an Audio DSP (digital signal processor, which is a Analog Devices SHARC ADSP-21488KSWZ-3A1).

If I am right about this, then I don't understand the talk of a transformer just at the 1795 outputs. In fact, maybe you can explain better to a layman like myself exactly how your output stage design improves upon what the HAP-Z1ES comes with from the factory.

The talk of the transformer is for the analog output stage (analog signal) in the I/V stage of the dac chips.  The Z1ES is not using a transformer.  They are doing I/V conversion via an OPA2132UA (burr brown op amp).

I am using a tube output stage (one for each channel, as there is one dac chip for each channel) in the output stage.  The stock unit is using opamps.  I am also bypassing some parts in the signal path and direct wiring from the Audio Output board to the tube stages (bypassing extra PCB traces, 2 molex connectors per channel, and the stock wiring).  And the tube output stages get their own dedicated linear power supply that I install. 

As for your quote:

...The output of the DSD engine is fed directly into the output stage which is based on high speed video amplifiers, passive filtering, including a carefully crafted high bandwidth audio transformer at the output. Unlike conventional DACS that depend on active analog output circuitry and the problems associated with them, DirectStream is purely passive.

I don't want to speak for PS Audio, but this quote has a contradiction.  See in bold above.  If it was purely passive, then it wouldn't use "high speed video amplifiers."   

Specifically, how would your output design differ in philosophy from this? Or is it even a relevant comparison?

I'm using two high bandwidth, Class A tube stages.  No transformers. 

- Vinnie

[rlabarre]

Thanks, Vinnie. Your explanations clear-up a lot for me. But what, then, does the FPGA do?

And, yes, I had noticed the same contradiction in the PS Audio quote.

[Vinnie R.]

Thanks, Vinnie. Your explanations clear-up a lot for me. But what, then, does the FPGA do?

And, yes, I had noticed the same contradiction in the PS Audio quote.

The FPGA does the signal processing for the PCM and DSD music files and and creates the I2S signals (for the d/a chips), mode control lines,
mute control, oscillator control, etc.

The raw 0's and 1's of your music files stored on your HDD cannot be directly sent to a d/a chip for conversion to analog.  They need to be formatted, digital filtered, etc. in such a way that the d/a converter accepts the bit streams.  D/A chips want a Master System Clock, Left/Right Clock, Bit clock, and data line (these are the I2S signals).  And mode control lines (so the d/a knows if it is getting PCM or DSD), mute control (so the output is muted when it powers up, or quickly muted and un-muted when it switches clock freq. based on the file you are feeding it).

Very simply put, the d/a chip says "give me clocking info, data, and let me know what data is for the left and right channels - and I'll crunch the data at the right times to create the analog waveform."  D/A chip does not want a raw music file given to it.  It needs to know how many bits are for each sample, what clocking freq. to use when converting, what data is LEFT, and what data is for RIGHT.  And it wants a very clean power supply and reference voltage to do its conversion. 

- Vinnie

[Vinnie R.]

Vinnie, this is the most informative thread about modding Z1ES so far - thanks a lot for it!

Hi Ivo,

Thanks, and thanks for all your interest!

I am a bit afraid of tubes since I have zero experience with them but will watch this place closely and who knows

Please do not be afraid.  You are just going to use the modded player like you would the stock player.  The tubes are in the inside.  They will last a very, very long time.  No ventilation issues.  It is auto-bias.  No worries.  If you want to swap tubes ("tube rolling"), you can, but you do not have to and right now with the stock JJ E88CC tubes it is sounding fantastic.  You do NOT need experience with tubes to enjoy it.  Trust me on this.

One repeated transformers question, please - are the primary Tx windings easily adjustable inside for 100/120/220V operation or they are custom build for each US/EU/JP version?

Ok - you are referring to the power supply transformer.  No, they cannot be changed from 120V  to 240V.... they are custom built.  If you wanted to use a North America (120V) version where 220/240V is used, I recommend an external step down transformer box (2:1 ratio) with a continuous rating of at least 60W (approx. 35W for the player + 15W for the tube stage power supply + some safety margin). 

Any ideas to design optional output buffer and analog volume control inside the unit so one can easily connect the power amp directly to Z1ES, please?

Yes, I wrote a post about that in this thread where I mentioned a few different volume control units that could be used.  I thought this over and have a good idea how I'd pull it off.  I haven't tried it because for the unit I am working on, the customer does not want this.

If you didn't care about having a physical volume knob on the front panel (you'd use the sony remote or the App to control it instead), then it could be done without any drilling of the front panel and the signal path would be very short and clean inside because the actual attenuation device could be mounted in the rear of the unit next to the tube output stage. 

And if you wanted an analog input that would also pass into the volume control and tube output stage, I could add a switch for that (so you could hook up an external analog source like a phonostage or iPhone/iPad for streaming Spotify or whatever). 

- Vinnie

[seadogs1]

Okay, all that has been said is all well and good the question remains: what are the advantages of your modded Sony over the PSA model?

[Vinnie R.]

Okay, all that has been said is all well and good the question remains: what are the advantages of your modded Sony over the PSA model?

I never heard the PS Audio and don't know how it compares... I'm sorry. 

[OzarkTom]

Okay, all that has been said is all well and good the question remains: what are the advantages of your modded Sony over the PSA model?

At 3x the price of a stock Sony, who cares? Do you think the PSA is 3x better sound?

[seadogs1]

 A Chevy and at 3x the price, the BMW. Do you think the BMW is 3x a better car? I do!

[Factorz]

And if you wanted an analog input that would also pass into the volume control and tube output stage, I could add a switch for that (so you could hook up an external analog source like a phonostage or iPhone/iPad for streaming Spotify or whatever). 

Vinnie can you talk a little more about this. I like the idea of having one box and being able to remove the Squeezebox from my setup.

[ted_b]

Okay, all that has been said is all well and good the question remains: what are the advantages of your modded Sony over the PSA model?

Seadogs,
Your insistence on this comparison is perplexing.  Why are you assuming that the two units have anything in common (except DSD, assuming you are speaking of the new PS Audio Directstream DAC)?  They are nowhere in the same category of functionality, position in the system or price point.  One is an all-in-one standalone player/server, and one is a new DSD-capable DAC.  As has already been enumerated, the player/server has its own storage, it's own GUI interface app, it's own cpu, it's own OS, etc.  The PS Audio DAC is a dedicated DAC that requires all the aforementioned pieces to already exist in one's system (plus cabling and power to all)...like any other DAC.  The Sony (and modded RWA Sony) is intended for an all-in simplicity...plug and play.  And all this functionality wrapped in a package priced 3X less than the PS Audio (maybe 2X once Vinnie is done   dunno).  Apples vs ashtrays.

The PS Audio Directstream DAC (I heard it last week when I spent over 2 hours with CEO Paul McGowan at his PS Audio HQ in Boulder) is to be compared to other $4k+ DSD-capable DACs (there are about 50) to be fair to any reasonable comparison discussion.   

It would be like asking if a $2K integrated digital dac/amp outperforms a $6k dedicated preamp.  Maybe due to synergy, but I doubt it..and in what function can they be compared? only switching and volume control really.   The former has amplification and digital inputs, the latter needs a DAC and amps already in place to compete and compare.

[DARTH AUDIO]

Seadogs,
Your insistence on this comparison is perplexing.  Why are you assuming that the two units have anything in common (except DSD, assuming you are speaking of the new PS Audio Directstream DAC)?  They are nowhere in the same category of functionality, position in the system or price point.  One is an all-in-one standalone player/server, and one is a new DSD-capable DAC.  As has already been enumerated, the player/server has its own storage, it's own GUI interface app, it's own cpu, it's own OS, etc.  The PS Audio DAC is a dedicated DAC that requires all the aforementioned pieces to already exist in one's system (plus cabling and power to all)...like any other DAC.  The Sony (and modded RWA Sony) is intended for an all-in simplicity...plug and play.  And all this functionality wrapped in a package priced 3X less than the PS Audio (maybe 2X once Vinnie is done   dunno).  Apples vs ashtrays.

The PS Audio Directstream DAC (I heard it last week when I spent over 2 hours with CEO Paul McGowan at his PS Audio HQ in Boulder) is to be compared to other $4k+ DSD-capable DACs (there are about 50) to be fair to any reasonable comparison discussion.   

It would be like asking if a $2K integrated digital dac/amp outperforms a $6k dedicated preamp.  Maybe due to synergy, but I doubt it..and in what function can they be compared? only switching and volume control really.   The former has amplification and digital inputs, the latter needs a DAC and amps already in place to compete and compare.

Well put!!

[seadogs1]

I'm Bad! You're Right!

[Vinnie R.]

And if you wanted an analog input that would also pass into the volume control and tube output stage, I could add a switch for that (so you could hook up an external analog source like a phonostage or iPhone/iPad for streaming Spotify or whatever). 

Vinnie can you talk a little more about this. I like the idea of having one box and being able to remove the Squeezebox from my setup.

Hi Factorz,

Welcome to AC and the RWA forum!

If a volume control is added, then you can connect directly to a power amp (no need for a preamp if you don't want to use one).  But, if you have another analog source, such as the output of a phonostage, then I can add an analog input and a switch on the back.  The switch will choose between the Z1ES, or the external analog source.  Both would go through the remote volume control and the tube output stage.  More than one analog IN and OUT could be installed because there should be enough room on that rear panel. 

Since the optional volume control and optional input select switch would both be installed in the rear of the unit and close to the tube output stage, the signal path will still be very clean and low noise.  With an external battery option, it would be very low noise and even better. 

I want to offer a base mod, and then some options that people can pick or not pick, based on their wants/needs.  Right now I'm finalizing the base mod.  Then I'll be exploring some other mods and options.   :

The modded Z1ES is sounding marvelous!  It pulls you in and if you are doing late night listening, it could be trouble because you will be low on sleep the next day. 

I'll report more about it later.   

[kngale1]

It would be like asking if a $2K integrated digital dac/amp outperforms a $6k dedicated preamp.  Maybe due to synergy, but I doubt it..and in what function can they be compared? only switching and volume control really.   The former has amplification and digital inputs, the latter needs a DAC and amps already in place to compete and compare.

For me, I only care about sound quality.    In stock form, Directstream is PROBABLY superior due to it's discrete analog output stage.    But after Vinnie's mod, who knows.    It's VERY VERY possible HAP-Z1ES will be superior to Directstream.   

Just the fact PS Audio is more expensive, no guarantee it's superior in performance from my experience in this hobby.

[ted_b]

Sure...could be...Vinnie is a genius.....but that wasn't my point.  And yes, we all should know by now that price is often not the sonic differentiator.

[OzarkTom]

For me, I only care about sound quality.    In stock form, Directstream is PROBABLY superior due to it's discrete analog output stage.    But after Vinnie's mod, who knows.    It's VERY VERY possible HAP-Z1ES will be superior to Directstream.   

Just the fact PS Audio is more expensive, no guarantee it's superior in performance from my experience in this hobby.

If you want a Direststream, all of April orders are sold out according to their website. PS Audio is now taking May orders.

If I were going to buy a Directstream, I would also buy the 1K Lightspeed USB cable, a $500 power cord, and a $2-3K power conditioner. Hopefully the sound would be great and probably will. Now I am  looking at over $10K for the package plus the computer. With Vinnies tube and battery mods on the HAP vs. PS Audio at my house, I know which one will win.

[kngale1]

Here's my .02 with consideration only to sound quality.

Due to it's limited input options, people view HAP-Z1ES as entry level.  Why do you need all the digital inputs if data is already on the internal HDD before play?  IMO, except for pre-loading tracks to the DAC's memory before play, it's probably superior to all external transports feeding the DAC real time. 

I heard a professional reviewer replaced the internal HDD with a SS HD with excellent results.

In stock form, it's obvious Directstream is superior due to the discrete analog output stage.  But is it a fact Directstream has superior digital processing?   With an equivalent analog output stage, is it possible HAP-Z1ES is superior overall?

[Vinnie R.]

I heard a professional reviewer replaced the internal HDD with a SS HD with excellent results.

Hi kngale1,

I want to look into this as well.  I'm thinking an equivalent sized 2.5", 1TB SSD can be had for around $500. 
Which reviewer replaced the HDD?

In stock form, Directstream is PROBABLY superior due to it's discrete analog output stage.    But after Vinnie's mod, who knows.    It's VERY VERY possible HAP-Z1ES will be superior to Directstream.   

Discrete analog output stage is not always better sounding, either.  Other factors are the power supply, clocking, board layout, FPGA, d/a converters, digital filters, choice of parts (resistors, caps, etc) .... implementation - implementation - implementation. 
Even the design of the discrete output stage, the FETs used (or BJT's or whatever), how it is biased, Class A or other - this all will have an impact on the sound.  Then there is "system matching."  In one system, it might sound great.  In a different system, the other player might sound better.

Long story short - It is similar to wine in that it is a matter of one's taste.     That is why there might be no clear winner in some comparisons.  The same is true for other components and speakers.     

And yes, sometimes the more expensive bottle of wine can't hold a candle to one of lesser cost, so price cannot tell us what is better all the time.

And speaking of opinions:

Due to it's limited input options, people view HAP-Z1ES as entry level.

IMHO, the Z1ES is very far from entry level.  But yes, when there is talk of the latest USB cable upgrade, the latest Awesome-Sounds 2.0 player to make your computer files sound better, and things like that - it is easy for some to perhaps lose perspective and the very elegant, dedicated, yet simpler design approach of something like the Z1ES design might not be noticed or appreciated.  Time will tell...

IMO, except for pre-loading tracks to the DAC's memory before play, it's probably superior to all external transports feeding the DAC real time. 

This could prove to be true - at least most of the time.  Again, we'll see.  But with the Z1ES design, Sony is really onto something! 

- Vinnie

[Vinnie R.]

With the “RWA-Z1ES-1”(Red Wine Audio Z1ES Level 1 Upgrade) completed, verified, and with A/B listening tests between the RWA-Z1ES-1 and the stock unit that I also have burned-in, it’s time for an update:

From the first listen to over 24 hours of total listening later, I find that the dual tube output stage addition has delivered a much higher level of soul and vitality to the music.  It’s not an “in your face” change that makes it sound like a totally different machine (and I wanted to retain the positive attributes of the stock unit) but definitely NOT subtle either. 

The midrange no longer has that somewhat dry character that the stock unit has.  There is more tone, more texture, and more life to both vocals and instruments.  The overall level of realism has improved with the tubed output stage doing its thing.  Be it piano keys striking, guitar strings being plucked, or hearing the body that should be attached to the person singing, everything sounds fuller and more real. 

There was another tweak that I did on the audio board (a bypass of sorts) that I found helped tighten up the low freq. bass response.  In its stock form, I was hearing a little bit of congestion around 60Hz and below region – this bit of lumpiness in the notes.  It turns out that an electrolytic cap in the signal path was solely responsible for that, and it also turns out that it was not needed anymore with the tube output stage.  So now the bass articulation is fantastic and pretty much spot on.

As far as the soundstage, there is more of it with the modded unit.  It goes from having good depth and “pretty good” width and height to something that is more expansive in all three dimensions.  With well-recorded DSD and high res PCM material, you can hear more into the room of the recording.  For example, quite a few of albums on the Chesky label were recorded at St. Peter’s Church in NYC.  I’m hearing more of that church now (same it true with CJ’s Trinity Sessions), like the subtle nuances that help trick your mind that you are “there” listening in. 

What happens with the modified player is that I want to keep listening because I get connected to the music better.  It’s that connection with the music that I found a little lacking with the stock player.  It’s not that the stock player is not enjoyable to listening to because it is, but it’s a different level of enjoyment for me with the tubes doing that voodoo that they do so well, and that is what has kept me up much too late listening on a few occasions already. When I’m in that zone, I know everything has moved in the right direction and I heard it the first evening of listening to the RWA-Z1ES-1 - and in the first track that I played (speaking of tracks, when I have more time I'd like to list some tracks that I've been testing with so hopefully some of you that know them will get a better idea where I am coming from.  But this will take some time).

The “airiness” and fine detail retrieval has not changed, neither has the overall good sense of balance that the stock player exhibits.  Now there is just more to the music that I love and the overall sound has a heightened sense of realism.  It’s juicier now, with more tone, more texture, more space.  It’s a more sophisticated presentation that I connect better with.  I found that I do lose some of that when switching back to the stock player (that already is a high achiever), and it is easy to notice when it goes away. 

I’m confident that the RWA-Z1ES-1 it will have no problem being compared to much more expensive units - and I have no reservations in making such a statement.   

-----

Where am I going from here?

1A) I need to gear up for RWA-Z1ES-1 modifications.  They will be offered for either the SE or BAL outputs.  I still need to finish up testing the balanced output version.  Pricing needs to be figured out.  A webpage on the RWA site needs to be added with more details of the modification and some pics need to be taken.  I hope to have this all set up and ready by early next week.

1B) I still need to look into add-on options such as the volume controlled output (and analog input) for those who expressed interest in feeding directly to a power amp.  This isn't a "next level" of modifications.  It will just be an added option that the user can choose based on their needs.

1C) Look into an SSD upgrade option.

2) For the next level, which would be the "RWA-Z1ES-2" I'll be focusing on improvements to the power supply sections.  Higher grade filtering and decoupling capacitors, ultra-fast recovery diodes to replace the stock diode bridges, and lower noise voltage regulators will be explored.
With better quality power feeds to the various sections, I suspect that the gains from the RWA-Z1ES-1 modification can be further realized. 

3) Beyond that, I'll be looking into a partial battery powered conversion via a customized Black Lightning LiFePO4 power supply.  Maybe it will be the "RWA-Z1ES-3".  This would feed the d/a converters, the clocks, and the tube output stages.  By replacing the analog transformer and power supply board with an external battery unit, there will be even more space inside for some other ideas that I've been thinking about!      

ALSO - I will try to be open to other things that might be on your "wish list."  Someone emailed be about a headphone stage and a lower powered amplifier stage already.  We'll see.  Keep the ideas coming.  I don't want to promise anything yet, but I will look into them. 

As you probably have gathered, I strongly believe in this unit.  It is an exceptional platform to work on and I have already proved to myself that it really takes well to modifications.  I admire its build quality, ease of use, and "sleeper" style in that it basic and not too flashy on the outside, but is serious on the inside where it really counts.  I have bought one for my own use and plan to even bring it to shows.  Even more, it now has me working in parallel on some improvements to one of my own products because I see that this modified Sony is surpassing my own!     

Vinnie 

[noiseless]

Hi Vinnie, this is great news coming from your camp - thanks for it! I feel very excited but in fact I didn't expect anything but improvement with your output I/V stage and hope it will be even bigger in "stage 2" with the modded PSUs - looking forward to it!

A side question for your tube stage, please - you already mentioned you removed a 'lytic cap from the signal path (thank God!) but will there be any other input, output, feedback caps in your output stage that can be changed for different sound presentations, please? I am sure I have an input cap on my power amp so if you have an output one it could be safely bypassed, I suppose?

Thanks!
Ivo