Home > General > Full Potential of Buffalo II at Last!

Full Potential of Buffalo II at Last!


For over two years, I’ve been trying of figure out why I was getting unlocks with the DPLL bandwidth setting at “LOW” and “LOWEST” with I2S input. I had attributed this to jitter from the interface. I’ve tried different interfaces (within my budget), tried modding the power sections of the interfaces, tried using different player software and whatever the audio community was experimenting at the time.

I think I am finally able to use the “LOWEST” DPLL setting without any unlocks. The latest “mods” consist of further shielding and vibration damping. This is starting to look like the type of mods people used to do to their CD players: damping, shielding, power cord/filter mods… I never thought those mods would make a difference…

The reason to go after the DPLL bandwidth setting “LOWEST” is to maximize the jitter rejection capability of the DAC. With this setting you can achieve the ultimate performance that the DAC was designed for.

Although I am not sure how repeatable the results are, here they are nonetheless:

Put some damping material on top of the clock (I think it is some kind of office-type of erase-putty)

Here is the additional shielding: a thin copper plate with two female pin connectors affixed to the plate and plugged into the exposed GND pins of the AVCC module

The following graphs record the number of unlocks per each 10-minute interval for 24 hours. During the first 60 minutes, the DAC will unlock many, many times. During this time the clock (etc) is stabilizing. Diyaudio wisdom indicates that it will take ~one hour for a good crystal to stabilize [link] so this is consistent with observation. Thus, for the Buffalo DAC, it will sound its best at least one hour after power-on

After the “warm-up time, the unlocks are seen clustered in bursts. One burst of 3 unlocks at 9:00 PM (I was listening the music at the moment and they happened within a few seconds of each other). The next two groups of unlocks during the second 6-hour interval and third 6-hour interval were recorded while I was sleeping or away, and they do seem to show up as a burst of unlocks.

I captured more data for another 6 hours (for a total of 30 hours). There were no unlocks in the last 6-hour interval


After that I did some focused listening comparing the sound between DPLL bandwidth set at MID-LOW (my previous reliable setting) and LOWEST. I used the track “Happy Now” of Poncho Sanchez’s “Conga Blue” album. After repeated non-blind A/B listening sessions, I am able to distinguish subtle differences. In particular LOWEST produces a “sharper”/”less soft” sound on certain instruments (for example, the sound from the cowbell). I think people call this “more focus” and “more layered” music.

More sensitive listeners may find bigger differences, but for me the differences are very subtle. In “normal” listening I would not have heard any differences.


The shield a bit modified

Heat exhaust holes

Making sure nothing is shorted by the shielding cage

  1. Florin
    March 18, 2012 at 09:18

    Great findings, it made me reconsider the topic of shielding in DACs

    • BlogGeanDo
      March 18, 2012 at 23:31

      Yeah, shielding gives undeniable improvements when using DPLL low and lowest settings. I don’t think my home environment is “polluted” with noise. I live in a newer residential complex and I only get one bar from the cell towers

  2. Chang LH
    March 18, 2012 at 23:58

    I do not fully understand the theory and you are discussion mainly for I2S, but recently I uploaded your latest BII arduino program (ver 10b) into my set. The new software is great and I use the 6 “inputs” to configure different settings for the same single input SPDIF. I found that if the DPLL is set to high or HST especially, the SR figure is not stable – it changes every few seconds or so, and jumps from one figure to another (between42,xxx to 53,xxx) which is strange – does it mean it can’t lock?. If i set the DPLL to low, LST or BST the SR figure is stable at a constant 44,095. I only use the SPDIF input direct from TEAC cd as a transport.
    And what about the quantization setting? I am lost – which should be set? 6bT, 7bP, 7bT, 8bP etc…
    Thanks anyway for the good job

    • BlogGeanDo
      March 19, 2012 at 01:53

      Hello Chang LH,

      I have seen the sample rate jump around too when the DAC cannot unlock to the signal. For SPDIF, it should always work with LOWEST for 44.1k material. Does it happen when the DAC is cold?

      I don’t know in theory what quantization means, but in practice, it reduces the use of digital channels inside the DAC by replicating inputs resulting in lower noise (as you increase quantization). I don’t know if you could hear any differences, but it is feature that is supported by a configuration register.

  3. Anonymous
    March 19, 2012 at 14:19


    I’m checking Your blog on almost daily basis and usually just remain speechless on Your great and extremely “scientific” ways of approaching things/problems…
    And for almost 2 Years follow Your pursuit of I2S unlocks on Buffalo …
    Now when You find out and publish (!!!) Your “dumper and shielding” solution on the Bufallo I admire You even more, specially that this “solutions” seems to bit against “pure scientific” usual approach… but more /what is the proper word./. esoteric ways..You seems to be usually far away of.
    I really wonder what Russ can comment when he will see “erase-putt” on Low Jitter Crystek clock….

    All the best as usual…. keep the great work …


  4. BlogGeanDo
    March 19, 2012 at 16:07

    Hi Rosendorfer, good to hear from you šŸ™‚
    I wouldn’t say “extremely scientific”, Just “scientific enough” with my available and sometimes improvised “tools”. But it is a lot of fun chasing after those tweaks. I don’t know how much of the improvement is due to damping the clock but if you read the I2S FIFO project at diyaudio, the clock board is hanging on rubber dampers and one reader said that the same approach is used in HP measuring instruments. The other “data point” is that in at least two occasions, I’ve experienced unlocks right after turning up the volume and then after that, it settles…. – so no real “proof” yet…

  5. Anonymous
    March 20, 2012 at 17:48


    Actually just because I read Your blog since long time and have “HiFiduino way” of mounting AVCC module, already for some time(!) I do have heatsink on my 2 ESS chips… šŸ˜‰ From now on I will call it also shielding..
    And, If You will find some nice looking way of damping Crystek clocks and I’m sury You will šŸ™‚ I will go for it also…;)..
    But actually the mater hire is that there is no denying that “damping” crystall clocks possibly can change things, but from “knowing” that “something could possibly be changing something” to actually being able to really measure the change and being able to clearly show it … there is quite a difference…. and You did it..!!!
    Actually I’m really amazed and surprised, specially that it is happening in very well designed Buffalo PCB using top shelf Crystek clock…I bet somebody is scathing his head about it …

    All the best and keep great work

    • BlogGeanDo
      March 21, 2012 at 04:17

      Hi Rosendorfer, you were the only one that reported no unlocks. I think the heatsink/shield was a big factor…
      In addition, it takes 60 minutes for the clock to stabilize. I wonder if oven controlled clocks are a good candidate…

  6. Anonymous
    March 21, 2012 at 13:18


    Well actually I’m using HiFace with 2x “Guido Tent Ultra Low Jitter” clock with all separated supplies….so it could be that my Bufallo do not have to work as hard as Yours…
    I know that You “love” your Musiland but maybe You demand just “one small setting” too much from it… ;)..
    Anyway I can see You just have fantastic looking(!!) new re clocker…with 2x new super clocks… ;)..have fun..
    Are You planing to go with new “fashion” of synchronous clock scheme with Buffalo..as I heard this sounds very promising….and also solves unlocks problems.. ;).


    • BlogGeanDo
      March 21, 2012 at 19:20

      Hi Rosendorfer, Yeah, it is possible separate supplies would help. The Musiland is using USB power. Regarding the reclocker, I am going to use it in asynch mode first and then figure out a way to switch the local clock on/off first.

  7. September 14, 2016 at 16:46

    tarjetas de plastico

  8. September 14, 2016 at 19:07

    digital goods with MRR and giveaway rights for free

  1. March 19, 2012 at 09:14
  2. August 21, 2012 at 17:08
  3. December 12, 2013 at 18:26

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