Phasure NOS1 vs. Pacific Microsonics Model Two

[PeterSt]

how about some of the more down to the earth details.

 

10.5Kgs

 

How long is the warranty?

 

Wasn't that stated two years ? maybe it was three. I really don't care much.

Once I had to pay for a car repair because warranty was over due 3 days. I will never forget that.

 

Is it sold directly or through retailers or distributors?

 

At this moment directly only. When that changes, price will go up. Turnover will be bigger, profit probably too.

But I guess this all didn't start out like that, and preferrably it will never happen.

 

What’s the financial stability of the manufacturer to back up that warranty?

 

Zero to none.

 

Despite my funny (meant) answer, I can tell you that your focus is on the wrong subject. Well, that is my personal opinion; It would be better to investigate how many PCM1704U-K chips I could obtain today, may it be for your DAC for tomorrow. The answer I just gave above.

Some people will sell their boat when things get tight. I will sell the 1,700 PCM1704's I already have, might that happen. At double the normal price. Next I will sell my boat.

 

I hope this tells you something about the real answer. Probably not (I wouldn't dig it :-).

 

 

 

[1audio]

"And to address Demian's point of a clock linked PM-2 being asynchronous at the same time, yes I agree, to a point. The PM Model still uses SPDIF, and this requires the attendent SPDIF receiver, which I believe it is correct to say, will still add (some) jitter even in a clock linked scenario. (Not to mention the accumulated jitter caused by the clock linking itself, cable losses/reflections, signal transmitter losses, etc.)-inherently, a system using a single fixed frequency clock, adjacent to the DAC chip(s), without having to send that clock anywhere else is ultimately going to result in the lowest possible jitter-assuming equal implementation."

 

It the PM Model 2 there is a dual crystal oscillator located very close to the DAC's. It runs at the "master clock" frequency. It is divided down to the bit clock and to the word clock frequency, a process that reduces the phase noise, the jitter remains constant. The external data source when locked to the word clock should have essentially no effect on the clock if the isolation is good. The key issue becomes eye pattern and data accuracy which is essentially perfect in this scenario. The data stream is driven by the clock next to the DAC, which is again ideal. (The PM uses AES dual wire for 192, not SPDIF. This is because when it was designed there were no 192/176 capable receiver chips.) This is in effect similar to what the NOS1 is doing.

 

Different DAC architectures are more sensitive to jitter at different clock inputs. Its not obvious from the outside which is more important without a good understanding of the guts. An early R/2R ladder DAC with a sample and hold on the output would be most sensitive to the word clock, since that drive the S/H. A Delta Sigma DAC is usually most sensitive to the master clock but not always.

 

Word clock became popular for locking different Digital Audio systems together because it would keep the data aligned pretty precisely and distribution is less sensitive to cable mismatches that bit clock or "superclock" (256X wordclock).

 

 

 

[PeterSt]

Hi Demian,

 

It the PM Model 2 there is a dual crystal oscillator located very close to the DAC's. It runs at the "master clock" frequency. It is divided down to the bit clock and to the word clock frequency, a process that reduces the phase noise, the jitter remains constant. The external data source when locked to the word clock should have essentially no effect on the clock if the isolation is good. The key issue becomes eye pattern and data accuracy which is essentially perfect in this scenario. The data stream is driven by the clock next to the DAC, which is again ideal. (The PM uses AES dual wire for 192, not SPDIF.

 

You will know more about the PM M2 than I do, but I can not understand all of what you are saying here.

 

It the PM Model 2 there is a dual crystal oscillator located very close to the DAC's.

 

It is allright to have oscillators in there, but they (IMO !) will be there for reclocking purposes only. Or some anynchronous SRC.

 

The data stream is driven by the clock next to the DAC, which is again ideal. (The PM uses AES dual wire for 192, not SPDIF.

 

Functionally speaking, AES will be SPDIF allright. Now, I really don't see how the data stream can be driven by oscillators in the DAC, while at the other end some oscillator(s) will be running, and *them* obtaining the data really;

If the connection would be async FireWire, yes, then I could understand.

but

Although I don't read it as such (and it will need the context of earlier posts I guess), when looked at this some other way around I don't see much what is wrong with your outlay. So, when the clock of the PM2 is connected to the original source, and *in there* the clock virtually is replaced by the one(s) in the PM2, yes. But only for theory and up to some degree, because it again (see my earlier post) depends completely on the architecture of this other source, and obviously this architecture is not under control of the PM2. So YMMV - it is nothing to depend on - users can not even check the real merits except for listening.

 

If we additionally take into account (and of course you said that yourself I think) that no word clock connection has ever been made for an application like this (better jitter specs etc.) - certainly not 10 or more years back - then I guess all we are doing is finding good reasons for an existing word clock connection of which we actually don't understand why it is there in the first place.

That all the Big Ben's jumped onto this market and that people happily buy these devices is good for them, but we may really wonder what perceived differences are really, while I'm not saying that they are not there. But as tests showed (sorry I don't have a link), all of these devices could only equal the jitter performance of the original source (IIRC but one, but now think of my "YMMV").

 

FYI (and where I stand in this), the specs (not up anywhere yet) of the NOS1 state explicitly that no word clock connection is provided because there won't be a single way it can be improved upon. It also states that the connection *is* there though, but internally, and with some DIY it can be exploited. Instead the specs also state that the oscillators can be replaced within 5 seconds (not counting the removal of the cover), might better ones become available. They could have been soldered and be more or less fixed in there, but we did not, for the better reason of being able to replace them in a whimp.

And of course this is all so because I think this is "the" way to deal with these things, or otherwise the word clock connection would have been there for commercial reasons at least.

 

 

It is divided down to the bit clock and to the word clock frequency, a process that reduces the phase noise, the jitter remains constant.

 

This may come across as nit picking, but if it were for me, then each division of the clock will result in additional jitter. Something like 6dB.

About the reduction of Phase Noise I can agree I think. But this will be merely because of the specs of the oscillator which are unavoidable for its frequency, while not using that frequency in practice (but a division of it).

I can easily be proven wrong here though.

 

Different DAC architectures are more sensitive to jitter at different clock inputs. Its not obvious from the outside which is more important without a good understanding of the guts.

 

Obviously (to me) this is completely true, and just what I said myself. So, I'm sure we don't disagree much.

I also don't want to know it better for someone who never even has seen a PM2 from the outside.

So let's wrap this up by me saying that I have my own ways, but also that I certainly don't know everything and all.

 

Thanks,

Peter

 

[1audio]

"It the PM Model 2 there is a dual crystal oscillator located very close to the DAC's.

 

It is allright to have oscillators in there, but they (IMO !) will be there for reclocking purposes only. Or some anynchronous SRC."

 

Reclocking can mean many things. In the model 2 the oscillators are used to drive the DAC's. When used as a master they are free running with no outside influence. When used as a slave they are phase locked to the external clock source, either from word clock in or from the AES stream. The PLL takes a long time to lock (as much as 10 seconds in some cases). This is typical of a high accuracy low jitter PLL. However in this case the clocks are running as Master.

 

"The data stream is driven by the clock next to the DAC, which is again ideal. (The PM uses AES dual wire for 192, not SPDIF.

 

Functionally speaking, AES will be SPDIF allright. Now, I really don't see how the data stream can be driven by oscillators in the DAC, while at the other end some oscillator(s) will be running, and *them* obtaining the data really;

If the connection would be async FireWire, yes, then I could understand.

but

Although I don't read it as such (and it will need the context of earlier posts I guess), when looked at this some other way around I don't see much what is wrong with your outlay. So, when the clock of the PM2 is connected to the original source, and *in there* the clock virtually is replaced by the one(s) in the PM2, yes. But only for theory and up to some degree, because it again (see my earlier post) depends completely on the architecture of this other source, and obviously this architecture is not under control of the PM2. So YMMV - it is nothing to depend on - users can not even check the real merits except for listening."

 

When a typical pro sound interface (Lynx, RME, Mykineros or even Juli@) is used with external clock or sync the internal clocking is locked to the external source usually with a PLL. In this mode the jitter of the data stream gets removed when the data is clocked (reclocked??) into the DAC. As long as the timing meets the requirements (set in the AES3 spec) the data will be accurate and the clock becomes that of the dac. Since the DAC is the master the buildup of Jitter in the soundcard gets removed as the data is clocked into the DAC.

 

"It is divided down to the bit clock and to the word clock frequency, a process that reduces the phase noise, the jitter remains constant.

 

This may come across as nit picking, but if it were for me, then each division of the clock will result in additional jitter. Something like 6dB.

About the reduction of Phase Noise I can agree I think. But this will be merely because of the specs of the oscillator which are unavoidable for its frequency, while not using that frequency in practice (but a division of it).

I can easily be proven wrong here though."

 

(Caution, Geek Speak ahead)This can be confusing since it depends on how jitter is defined in the context. If the Jitter is in absolute (RMS pS) then the jitter is constant (especially with a synchronous divider) with a very small penalty from the gates used. If specified in UI (unit interval) is actually is reduced as a function of the interval since its pretty constant and the interval is increased. The phase noise is reduced by 6 dB with every division for the same reason. Multiplication to higher frequencies has the reverse effect, leading to some curiosity as to how a word clock source can provide lower jitter than the internal clock. Perhaps good PLL's in those cases where it works? Or really poor clocks to start with?

 

Crystal oscillators tend to have the lowest noise at 5 MHz, increasing as the frequency goes up or down. The ultra low noise oscillators are very expensive. There is also a question as to when do the limits of the DAC prevent an improvement from improved oscillator performance. (FWIW, there are no 24 bit accurate audio dacs. There are a few slow 24 bit dacs but they are not useful for audio. A 32 bit dac is pure marketing, as the designer of one explained to me, thermal noise will prevent any meaningful output at bit depths much less than 32 bits.)

 

 

 

 

[Miska]

A 32 bit dac is pure marketing, as the designer of one explained to me, thermal noise will prevent any meaningful output at bit depths much less than 32 bits.

 

Yes and no, the thing is more complex. It reduces need for lowering the precision between DAC and prior processing stages. It also gives more flexibility to deal with noise shaping inside DAC's modulator stages. So the digital domain performance can get better.

 

At least it removes all the "losing the bits" arguments against digital volume control for RedBook formats...

 

And if you look for example at datasheet of BB PCM1795 and the -144 dB and -150 dB output spectrum figures on page 14 you'll see that things are getting scaringly close to 24-bit at certain frequencies when FFT is long enough and there's enough averaging. Just zoom enough on the PDF.

 

So it depends how you look at things, since I'm pretty much specialized in software digging out weak signals from noise I can assure you that there are ways to detect really weak non-random signals out of random noise. And any crypt-analyst could tell the same...

 

My favorite demonstration is a software signal generator mixing different types of noise and sine waves at varying levels and frequencies for people to listen at which levels the signal completely disappears in noise from human auditory system. Audacity can be also used for the purpose, generating noise and sine and mixing the two together.

 

 

[manisandher]

“I wondered if after a little more listening time, your impressions stay so positive”?

 

Yes, I remain pretty much enamored with the NOS1. There is a purity to the sound that I’ve simply never heard from any digital or analog source before.

 

My Model Two remains switched off nowadays, being used purely for ADC duties when required. As a DAC, it just can't match the NOS1. However, there is one consolation - 16/44.1 HDCD and 24/176.4 HRx commercial releases are some of the best sounding files I have in my collection and sound totally wonderful played back on the NOS1.

 

Mani.

 

 

[TimDH]

Mani,

I was hoping you could post picture(s) of the PCIe connection from the computer to the NOS DAC. Since I'm a Mac person, I'm not sure if your generic PC these days has a PCIe interface standard, or you need to configure your PC with one specially? Also, any comments on the specs of the PC you use- the question of how much computing power XXHighEnd needs?

Thanks!

TDH

 

[losingmyreligion]

 

"My Model Two remains switched off nowadays,"

 

That's quite a testimonial. We know how much you love the Model 2.

 

Mani, does this mean there's a chance one of us might be so lucky as to acquire your Model Two without being in your will? ;0

 

 

clay

 

[PeterSt]

Mani,

I was hoping you could post picture(s)

 

Hi Tim,

 

Please don't blame Mani for not doing it. I said I would do it, so he needn't to. But I guess I'm not good at doing things some half way, and at promising "pictures" I want good pictures. This is not easy, and it may take me half of a day. It needs the good light too, and blahblahblah. But I'll make a picture of that interface in a few hours time now, after sunrise.

 

Mr Commercial. Hmm ...

 

 

[manisandher]

"Mani, does this mean there's a chance one of us might be so lucky as to acquire your Model Two without being in your will? ;0"

 

Hi Clay,

 

Haha. No, my Model Two's here to stay... albeit in a purely ADC capacity nowadays. There's a 'quality' to recordings made on a Model Two that I just love. I record at 24/192 myself and then tend to upsample to 32/384 in XXHE before feeding to the NOS1. Although I have to say that even commercial 16/44.1 HDCD releases upsampled to 32/352.8 in XXHE sound particularly good on the NOS1.

 

Mani.

 

[SteveChicago]

@ Clay: Though Mani's not selling there are one or 2 for sale on Audiogon ... but you might need a bridge loan. Perhaps Mani can offer a competitive rate ... :-)

 

Q

 

[losingmyreligion]

 

 

"Haha. No, my Model Two's here to stay..."

 

I'm not surprised, but you can't blame a guy for asking, right?

 

 

 

Steve,

 

thanks, yes, I'd heard that. I'm quite happy with my current DAC - a Metric Halo LIO-8, esp at those prices.

 

Clay

 

 

 

 

 

 

 

[PeterSt]

At last ...

 

This is a not completely ready DAC. But it allows for some site-seeing.

 

 

 

The PCIe (1x) interface in the PC is in the middle of the picture here.

Some dust cleaning is needed allright.

 

 

 

And the outside of the PC ...

 

 

 

Towards the DAC ...

 

 

 

Connected now ...

 

 

 

... in some perspective ...

 

 

 

Seen from the inside of the DAC.

 

 

 

From some other angle ...

 

 

 

... in close up.

 

 

 

But back to this angle.

 

 

 

From the other side ...

 

 

 

... and from this close ...

 

 

 

... and again from another angle ...

 

 

 

... and from the outside of that.

 

 

 

From far, far away.

 

 

 

But from closer again here with a walk around.

 

 

 

And step a little to the right ...

 

 

 

... or a little back.

 

 

 

Seen from the interface itself ...

 

 

 

... in closeup.

 

 

 

Seen from that closeup.

 

 

 

And from a helicopter ...

 

 

 

... just on top if it.

(due 8 channel X-Over version, 16 chip)

 

I hope this suffices.

And isn't too much of it.

 

Peter

 

[ted_b]

look forward to the pictures. Somehow the links are gone.

 

[PeterSt]

Thanks Ted. But, strange. Here they're just visible. Also from the "outside" (a VPN).

 

But I have heard similar before ...

 

If you briefly ask for e.g. this one : http://www.phasure.com/index.php?topic=833.0

(all old stuff)

Do you see that ? (pics)

And if so, if you now refresh this thread, does it help ?

 

I'm off and dead anyway, so I hope to read your response later.

 

Thank you,

Peter

 

[av_passion]

Peter,

 

Can you fill us in on the details of the 8 channel version? Will it allow you to implement an active crossover within the DAC like a Metric Halo Lio-8?

 

[ted_b]

Thx (and yes, your screen grabs on the installation guide thread showed up fine).

 

[manisandher]

I've just been listening to Claire Martin's "Too Damn Hot" album recorded at 16/44.1 HDCD.

 

This sounds very good played back bit-perfectly through XXHighEnd (i.e. no upsampling) and feeding the Weiss AFI1 to PM Model Two. Here, the Model Two's PMD100 filter is engaged and is decoding the HDCDC signal. However, the album sounds altogether superior through the NOS1. I've used the word before - there is a purity to the sound that is utterly beguiling. Of course, here I'm upscaling the 16/44.1 HDCD signal to 32/352.8 using XXHE's zero pre- and post-ringing "Arc Prediction upsampling". Also, importantly, I'm using XXHE's "Peak Extend" feature - although XXHE comes with an HDCD decoder as standard, I don't like the way it sounds and tend not to use it.

 

Actually, there is such a difference in performance that I'm wondering whether the AFI1 is really up to the job of serving the Model Two.

 

Mani.

 

[PeterSt]

Mani - Maybe it's a stupid idea, but why not ask Keith Johnson what he used in the past for best performance ? Of course he shouldn't come up with equipment we don't have in our homes (hence can't judge that). Anything "modern" wouldn't be helpful for an answer either I think, but since the thing will be 10 years old ... what did he use back then ?

 

Could be some Lynx ...

 

Maybe to keep in mind : It is my personal idea that all Firewire is a kind of "out of control" so to speak, be that BridgeCo based or be it DICE (Weiss afaik) based.

RME is left out of this equation, because it is proprietary.

 

You may not know about the subject, but I have been working for a year (throughput time) on a Firewire interface, but when I at last had everything together (my !) latency specs couldn't be met, and I gave up for that reason alone (apart from it's a mafia world). This was before we could use the ultra low latency in software, but I guess since we now can, the data prooves that this is just so. You were one of the first to find out ... (Jealous Guy).

 

Just speculating ...

Peter

 

[gkoones]

I might be showing my age, but the first thing that came to mind was Heathkit or Eico, but more primitive.

 

[4est]

I have yet to see a positive post from you. Are you here just to complain, or do you have something positive to add to these discussions?

 

[1audio]

Keith uses a Lynx card on a Mac running Soundblade, or a Mykerinos card on a PC running Pyramix or a Lynx on a PC running Media Monkey with a BADA DAC depending. . .

 

He doesn't use any of the above for recording.

 

[manisandher]

I'm not surprised KOJ uses Lynx cards - was there even a choice before the RME AES-32 came along? I myself have the latter, though I've no idea how it compares to the Lynx. I have however compared it extensively to the Weiss AFI1, but can't really decide which one I prefer. They certainly sound different.

 

So, KOJ doesn't use a Lynx or a newer Mykerinos for recording, hey? What on Earth does he use then? Can you reveal anything here Demian, or is it a RR trade secret? Whatever he's using, is it purchasable? (IIRC, he uses his own speakers for monitoring, which apparently are not purchasable.)

 

Maybe I should commission someone to stick an OEM ESI soundcard in my Model Two and take a I2S feed from it... works a treat in the NOS1!

 

Mani.

 

[gkoones]

I think its very positive to challenge a vendor with a financial interest in selling a product packaged in what looks like high school shop class sheet metal at 10 to 20 times its cost of goods.

 

[manisandher]

What? I have the NOS1 sitting here, and it looks nothing like you describe. And what's more, it's cost of goods is bloody high - this is obvious when you take a look inside it.

 

gkoones, you're a twat.

 

Mani.