Modding the DirectStream DAC MKI

In Cayman I have a 2017 GT-R Nismo RHD, 203mph is what the factory claimed but there’s nowhere on island to try it, 0-60 it’ll take any car on the island, even Iggy’s tricked out 911 and some guy with a GT-40

Interesting, I have not seen a verifiable claim the car will break 200 MPH. One cannot get a two ton car over 200 MPH with only 600 HP. It is just basic physics.

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https://www.tesla.com/roadster

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It is hard to beat 100% torque at 0 RPM and all wheel drive. :slight_smile:

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With a modified exhaust and upping the turbo boost we got 720hp on the dyno and I still think 200 is iffy. Just doesn’t have the aerodynamics as the variable resistance fluid the air is gets prohibitive. That said, I never tried it but there was a lot of headroom at 150mph seemed like 175 was a no brainer, 200 who knows

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Common sense (and courtesy) Folks…

We’re not here to rip PSA off, lets assume they aren’t either.

and Kudos to Ted for managing the sea of expectations based on his every word.
He did it right.

DS owners…
your in good hands, chill.

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Tell me another Manufacturer that engages with the Customer the way PSA do?

Everyone’s got an opinion (check Twitter) doesn’t make it right?
Were not fighting with each other here…right?
Sometimes you have to walk away from hifi Nervosa for the sake of your own Health.

Ted and PSA, way smarter than us and they have got this…
Not their first Rodeo and Directstream has been supported since it came out.

SO RELAX
They are the good guys.

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PS Audio has to be the most awesome company on earth. First of all what other company to you talk to the Engineer and CEO? Then the CEO says he does not mind if you modify the product! Holy smokes! I am not modifying mine though. I have a much better DAC anyways. Although TBH the DSS is close! That is 130 grand difference!

My GT-R is leased so it just has a tune on it. I cannot do down pipe or anything. So maybe mine has 640BHP.I did make a mistake about the 248mph. Maybe mine could go 210-215. TBH I never went over 140. 0-60 is fast though. I have not have anything close to beat me. Left brand new ZR1 in the dust. From rolling start I passed it by about 10 car lengths. I am not kidding. The thing is he could not get traction because he did not use launch control. You can’t from a rolling start. Tesla is fast but I am not ready for short range.

If it ain’t broken…don’t try to “fix” it.

I modified my Koss MassDrop ESP/95X with SoniCap 's on all the audio signal paths. and it help but swapping op-amps did improve things slightly but there’s still some things audibly “wrong” because these things scream so much detail, my ears are now sensitive to certain frequencies when played though these things. I may buy the STAX SRM-007TA/SRM-007TII tube input Amplifier which everyone says improves things 100x without having to spend $4k on the STAX SR-009S.

Of course me messing with a $250 Electrostatic Headphone “Exciter” isn’t the wisest move. But a $5k DAC ? Why would you unless you have money to burn ?

Mass doesn’t have much to do with top speed. It’s horsepower vs drag and that is mostly aerodynamic drag. Yes, weight does increase tire and bearing drag but that is minimal.

Mass does affect acceleration greatly and how long it takes to get to the vehicles top speed!

That’s the basic physics of it.

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Yes, but you still have to accelerate that mass while overcoming drag. But drag is indeed far more significant.

In any event, a GT-R is not going to exceed 200 MPH stock or mildly modified.

The all wheel drive of the Nissan makes it an car easy to launch.

But where it matters, the ZR1 is a full ten seconds faster a lap on Virginia International Raceway’s 4.1-mile Grand Course. This is an eternity when it comes to which car is faster.

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My main criteria for selecting a VCXO are it needs 100ppm pullability (for CDs) and low phase noise. The TSS will use the same VCXO as the DS since I don’t know of a better one.

If a DAC accepts TOSLink, S/PDIF or AES3 you only have two choices - use a VCXO or use asynchronous sample rate conversion. I obviously choose a VCXO. If we ignore those inputs, asynchronous USB could use a fixed frequency oscillator instead of a VCXO. (Tho the phase noise at the center frequency of the VCXO should be the lowest, so it’s not as advantageous as one might think to use a fixed frequency crystal instead of a VCXO.)

Tho I2S on many chips supports a master clock at either the source or the destination, most implementations of it over an external connection don’t allow the DAC to be the master. So you are back to a VCXO (or ASRC.)

My opinion never was that the VCXO should be close to the FPGA. It’s always been that it should be close to the point in the DAC where a clock is used for the last time: i.e. right at the point where digital becomes analog. Loosely speaking at “the last reclocker.” In the DS and the TSS the VCXO is right at the last reclocker on the analog card.

SAWs have much more phase noise than a crystal.

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Wait!

There is some sort of Audiophile Goo out there? Where can I get this Goo? Is it super expensive? :astonished:

:upside_down_face:

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Someone once told me that removing the IEC filter thingamabob makes a nice difference.
And said guy is scary smart.
I didn’t do it, though

I am now learning that VCXO is better than Femto? Is this really true? So now my big bucks MSB is not so good any more? I don’t really have room for2+ boxes unless I do major remodeling. Will there be a 30 day trial on the TSS like most PS stuff? I have a feeling it will kill the MSB. Since the DSS is already very close(stock) with good signal chain. I can still sell the MSB for more money than the TSS. Assuming the TSS is under 45 grand. Ted, is this no holds barred? As the DSS was built to a price point. The TSS has no price constraint whatsoever? You will just do the best you know how? If so it should be the best DAC in the world. For now I will have to put it on an amp rack on the floor. I think your signal chain is a bigger difference than any mod you will be able to make to the DSS. I personally did not like the Matrix spdif2 and did something else entirely. It was more expensive and involved more “boxes” but i am just loving the sound. I even added boxes to the AES3 on the CD transport and it improved it tremendously IMO.

I did not know the ZR1 was that fast. Now I feel bad. The ZR1 is half the price of my car. I really do not know why a Nissan is so expensive for only 600BHP? It is not even an Infiniti. I still like it. People compliment it all the time and I like that. Yeah, I am pretty shallow. I bet the Shelby mustang can beat it and that is only like 70 grand. TBH I really just prefer my Range Rover! It is my wife’s truck. I feel better when I drive that. Don’t have to worry curb the rims and everything. Plus some idiot hit you. I wanted to mention the thing is a dog unless in “R” mode. It should be fast when you turn it on IMO. Overall, maybe not quite worth the price. Except the 0-60. Nothing can touch 2.3 seconds. I am not sure how a 2 ton 600BHP car even does that.

Sorry for still off topic but you guy’s made me unhappy with my car!

Ted, I hope you answer the DAC questions please. Thank you

“Femto” has been used as a buzzword. There are digital clock synthesizers with excellent specs as far as jitter is concerned, but aren’t very good for audio. No single number tells you what you need to know about jitter performance for audio.
I believe that the MSB clocks are good (it’s been a while since I looked at them. But it’s the whole system that matters (not that I’m saying the MSB system isn’t good, I’m not.))
Yes PS Audio will have their customary 30 day trial.
The two boxes can be 10’s of meters apart if you want. I’d put the digital box near the digital stuff which hopefully isn’t next to the analog stuff. It won’t need a fancy base, etc. so it should be easy to place.
There are a lot of posts in the “Cost no object DAC thread” about the realities of building a product. In short I don’t want licence to spend the customer’s money on things with, say, only 0.1% improvements. Surely there are better places for customers to spend to get better sound. My first TSS design had almost twice the budget. I spent even more time on the second design spending money more carefully, and I’m sure the 2nd design will sound better for it. (It’s easy to design without cost constraints, but real engineering is being cost efficient while still meeting the goals.)
The TSS should be less sensitive to power cords, interconnects, etc. and it should be able to be configured better for a broader set of systems.

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Two questions please Ted.

Do the two boxes require a proprietary cable to connect to each other?

I was wondering what you thought about putting clocks in “ovens”?
I am pretty sure that even the MSB does not have an oven.

The cable can be bought at DigiKey, Mouser, etc. It doesn’t need connectors, just a clean cut with a razor blade to trim to length (you can buy the captured/safe blades along with the cable. Besides shorter lengths it comes on 500’ rolls so PS Audio will likely ship a medium length with the DAC and offer low or no cost lengths for those that request them.
Ovens are for long term stability, audio needs only short term stability (e.g. low phase noise.) However if you get an ovened crystal it will likely also be a good crystal with low phase noise.

Yes, that is why some companies like to use ovens. So their DAC’s last a very long time for you. Usually in pro audio though where people tend to keep gear longer. Audiophiles tend to get the latest gear. You were up pretty late :slight_smile: PS Audio is like none other. Talking to the Engineer past Midnight! I am so inept I will cut off my finger doing that lol. I guess I will figure it out. I am guessing it is an optical cable or something? I have a shop that will probably terminate it for me at no cost. Thank you Ted