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Introducing the Buffalo III-SE-Pro 9028/9038

"That should be doable - I would probably use two Placid HD-BP if I had space. Also you would need a fair bit of shunt current to handle transients I would shunt something like 200-250ma per pair of Mercs."

1. Russ, I suspect the above means the Mercury is not running in class A?

2. I assume you are suggesting to plan on 200 mA per rail consumption for a single (stereo)
Mercury set up, right?
 
"That should be doable - I would probably use two Placid HD-BP if I had space. Also you would need a fair bit of shunt current to handle transients I would shunt something like 200-250ma per pair of Mercs."

1. Russ, I suspect the above means the Mercury is not running in class A?

2. I assume you are suggesting to plan on 200 mA per rail consumption for a single (stereo)
Mercury set up, right?

1. It is similar in behavior to IVY in regard to power consumption - just a lot more :)

2. Correct. I will get more specific later - but that's a good ballpark guess.
 
Probably. It appears to be a through-hole part, so you will need to figure out how to mount it without making the trace lengths to long.

You can wire in any compatible clock you like via the header or the uFL connector. Simply omit the trident that powers the on-board clock.

Would you consider making installing Pulsar Clock easier on next Buffalo III board revision (e.g.: prepared holes like in Ians reclocker) ... ?

I thought about monster build: Buffalo III 9038Pro + Plusar Clock 100Mhz + Mercury.
 
dual mono 9028 vs single 9038

Hi Russ,

Question between 9028 and 9038. Which would have better SQ, a dual mono 9028 implementation? or a single 9038 implementation? assuming the same I/V stage? since the difference in these two are just the current output, I figure one 9038 would be a simplier implementation and could even sound better.
 
Hi Russ,

Question between 9028 and 9038. Which would have better SQ, a dual mono 9028 implementation? or a single 9038 implementation? assuming the same I/V stage? since the difference in these two are just the current output, I figure one 9038 would be a simplier implementation and could even sound better.

Some DAC chips sound pretty good with 2ma, so I would think the diff between these two chips is marginal to not noticeable. The 9028 seems a better choice as you get options for I/V stage.
Perhaps its the new architechture and filters that would make this a better dac than the previous Buffalo dacs rather than the amount of current available.
 
9028 vs 9038

Some DAC chips sound pretty good with 2ma, so I would think the diff between these two chips is marginal to not noticeable. The 9028 seems a better choice as you get options for I/V stage.
Perhaps its the new architechture and filters that would make this a better dac than the previous Buffalo dacs rather than the amount of current available.

You are correct, if you are upgrading from a dual mono configuration and already have an I/V stage for it, my question however, is if one is building from scratch and have nothing at all. Building a dual mono 9028 is much more complex and costly than a simplier single 9038. I am comparing between a dual mono 9028 vs a single 9038.
 
Cronus...

Russ,

Is it possible to easily replace Crystek 100Mhz clock with OCXO Pulsar Clock 100Mhz on new 9028/9038 Buffalo III boards?

My plan is to run a Cronus board, Sync clocking the B-III PRO, using a 45.1584 Pulsar. I oversample everything to DSD 128, so will only need the single frequency XO in this cases and the Pulsar can easily be fitted to a DIP socket on the Cronus board. I have always preferred sync clocking the 9018, and do not expect that the 9038 will be any different in this regard.
Additionally, one gets better phase noise performance of the XO with the lower rate.
 
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Building a dual mono 9028 is much more complex and costly than a simplier single 9038. I am comparing between a dual mono 9028 vs a single 9038.

The Legato I/V stage (my preference vs. IVY) tweaks nicely with upgraded caps and custom resistor pairings. If that piece of the puzzle is important to you, then the choice of DAC chips is clear. I’m curious if Russ experimented with transformers for the 9038? ;)

Matt Shaw is ignoring my request for a data sheet. Any suggestions?
 
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My plan is to run a Cronus board, Sync clocking the B-III PRO, using a 45.1584 Pulsar. I oversample everything to DSD 128, so will only need the single frequency XO in this cases and the Pulsar can easily be fitted to a DIP socket on the Cronus board. I have always preferred sync clocking the 9018, and do not expect that the 9038 will be any different in this regard.
Additionally, one gets better phase noise performance of the XO with the lower rate.

Exactly I wish there was DIP socket for Clocks in Buffalo III Pro board, like it is already on Cronus board, then one would easily replace Crystek with Pulsar.

I know es908x works better in synchronous mode, but in my particular case I will use asynchronous clocking.

Russ do you think you could add such DIP socket (Rhea Module) to Buffalo III Pro board? It would give more flexibility, which is one of the key value of your designs.
 
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Exactly I wish there was DIP socket for Clocks in Buffalo III Pro board, like it is already on Cronus board, then one would easily replace Crystek with Pulsar.

I know es908x works better in synchronous mode, but in my particular case I will use asynchronous clocking.

Russ do you think you could add such DIP socket (Rhea Module) to Buffalo III Pro board? It would give more flexibility, which is one of the key value of your designs.

We discussed it. It's a lot more work to hand solder the number if Rhea boards I would have to make (tiny pins). It's really an edge case anyway, and there are other ways to add external clocks.
 
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Buy some chips? It took a couple of weeks but I did the NDA, bought a pair of 9038s, and was provided with a data sheet with my name in the watermark. Not much in there regarding IV design, though.
Bought already - attached to a TPA board. I sent another note to Shaw. There’s really no hurry.

I just want to learn everything that can be accomplished via I2C. In particular, I’m curious about the harmonic distortion corrections, wondering what kind of potential the new chip has. FIR, I assume? If so, how many taps and what base frequency? The 9018 has little more than enough processing to ably manage HF noise. If the 9028/38 can correct audible harmonic distortion, might it be possible to add either phase-aligned crossover filters or crossover phase-correction filters in the same coefficient set? It would be pretty awesome to do that right in the DAC and my existing system [with 3 BIIIse boards, one channel per amp channel & driver] could benefit tremendously.

Cheers,

Frank
 
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Matt Shaw is ignoring my request for a data sheet. Any suggestions?

I'm delighted that Matt just forwarded the data sheets! :) Interesting reading, and no, not really enough taps to take on ambitious filtering. Though I'm still interested in being able to load custom curves. I will study the suggested C code and eventually try to execute something like it in python. ...plenty of work before that stage is reached...

Cheers,

Frank
 
Thanks to Brian making quick work of getting the parts I am listening to the 1.0 version of the Mercury right now. :) I will start a new thread soon. But I will say this - it is sounding just awesome. :) - Absolutely no sweat handling the full 9038 current - full scale output from the DAC does not even come close to clipping the front end and the scope sine wave looks perfect!

There is a very small error in the Version 1.0 boards - but nothing that will throw anyone for a loop if they want Mercury now (rather than waiting a couple weeks for new boards). I will be ordering 1.1 boards soon but the only change will be fixing that error (a disconnected GND pad on the right balanced output). I will discuss this with Brian but we might go ahead and make 1.0 Mercury available now - working around the error is as simple as placing a jumper from a nearby cap GND pad to the output terminal block pad. It has zero impact on the circuit performance.

I am super excited - Mercury is a pretty serious improvement to my previous output stages on a number of levels. Not just for the 9038 but even the 9008/9018/9028 etc.

Cheers!
Russ

Thread coming soon!
 
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