Burson Audio op-amp mod.

pearsall001
pearsall001 Posts: 5,068
edited August 2010 in 2 Channel Audio
After I bought my Music Hall dac25.2 I knew I was going to have some fun with a few DIY projects with it. But first I must comment that the MH dac sounded fantastic right out of the box. No complaints here on that note.

My first fun swap was to replace the stock EH Russian 6922 tube with a NOS Amperex Bugle Boy tube. After a good 125hr burn in the difference the Bugle Boy added was not at all subtle. Everything just sounded more "alive" & more involving. Soundstage, imaging, & vocals just took on another life of their own. Things were really heating up around here with my eagerness to give my next project a go.

In steps the Burson Audio dual HD op-amp upgrade. I ordered direct from Burson & received them in 8 days. The install took all but 10 minutes. The stock op-amps simply popped right out & these guys went right in. After a good 100hr of burn in the results were simply amazing!! I couldn't believe what I was hearing. Kudo's to Burson for such a fine product.

So now between the new tube & op-amps I'm really, really satisfied with this dac's incredible sound. But as tweakers go I'm still on the fence about replacing the stock caps with some nice Auri caps. I just don't know if they would take things to even a higher level. If I do proceed with the Auri caps I can assure you that my DIY fun with this dac will be complete. Nothing like having a little fun with the gear.

What do you think...do the caps or what???? :confused:
"2 Channel & 11.2 HT "Two Channel:Magnepan LRSSchiit Audio Freya S - SS preConsonance Ref 50 - Tube preParasound HALO A21+ 2 channel ampBluesound NODE 2i streameriFi NEO iDSD DAC Oppo BDP-93KEF KC62 sub Home Theater:Full blown 11.2 set up.
Post edited by pearsall001 on

Comments

  • heiney9
    heiney9 Posts: 25,165
    edited August 2010
    I bought the Burson op-amp regulators for my Adcom dac. Also upgraded the ancient stock op-amps with new OPA627's at a cost of $100. Upgraded the power supply caps with Panasonic FC's and Nichicon and also upgraded the Op-amp coupling caps with Multi-caps and REL caps.

    Not even the same dac!!! I would have used Auricaps in the coupling position but they didn't have anything close to the ratings I needed. I have a couple Dared tubed pieces that use Auricaps standard and they sound wonderful. I am getting ready to upgrade my Norh tube integrated with Auricaps. A very worthwhile upgrade IMO.

    FYI

    http://www.polkaudio.com/forums/showpost.php?p=1306559&postcount=74

    http://www.polkaudio.com/forums/showpost.php?p=1316096&postcount=108

    http://www.polkaudio.com/forums/showpost.php?p=1316761&postcount=115

    Auricaps will take things to the next level, no doubt. My favorite medium cost signal path capacitor.

    H9
    "Appreciation of audio is a completely subjective human experience. Measurements can provide a measure of insight, but are no substitute for human judgment. Why are we looking to reduce a subjective experience to objective criteria anyway? The subtleties of music and audio reproduction are for those who appreciate it. Differentiation by numbers is for those who do not".--Nelson Pass Pass Labs XA25 | EE Avant Pre | EE Mini Max Supreme DAC | MIT Shotgun S1 | Pangea AC14SE MKII | Legend L600 | BlueSound Node 3 - Tubes add soul!
  • pearsall001
    pearsall001 Posts: 5,068
    edited August 2010
    Great info Brock! I see you mentioned that the Auri caps are your favorite medium priced cap. What other one's should I also look at as an upgrade over the stock caps if price isn't an issue? I know that one can get carried away with mods but if I make this my last mod to the unit I want it to sing.
    "2 Channel & 11.2 HT "Two Channel:Magnepan LRSSchiit Audio Freya S - SS preConsonance Ref 50 - Tube preParasound HALO A21+ 2 channel ampBluesound NODE 2i streameriFi NEO iDSD DAC Oppo BDP-93KEF KC62 sub Home Theater:Full blown 11.2 set up.
  • Face
    Face Posts: 14,340
    edited August 2010
    What values are in the signal path?
    "He who fights with monsters should look to it that he himself does not become a monster. And when you gaze long into an abyss the abyss also gazes into you." Friedrich Nietzsche
  • pearsall001
    pearsall001 Posts: 5,068
    edited August 2010
    If my memory serves me well...they are 1.3 uF. I'll have to pop the hood & take another look but I'm almost positive that this is correct. Any suggestions for the upgrade.
    "2 Channel & 11.2 HT "Two Channel:Magnepan LRSSchiit Audio Freya S - SS preConsonance Ref 50 - Tube preParasound HALO A21+ 2 channel ampBluesound NODE 2i streameriFi NEO iDSD DAC Oppo BDP-93KEF KC62 sub Home Theater:Full blown 11.2 set up.
  • heiney9
    heiney9 Posts: 25,165
    edited August 2010
    Great info Brock! I see you mentioned that the Auri caps are your favorite medium priced cap. What other one's should I also look at as an upgrade over the stock caps if price isn't an issue? I know that one can get carried away with mods but if I make this my last mod to the unit I want it to sing.


    Other choices could be

    V-cap Teflon (very expensive)
    Vishay-Roderstein
    Mundorf paper in oil
    Sonicaps
    REL caps
    Multi caps.

    Here's a link to Part Connexion; click on the film capacitors section

    http://www.partsconnexion.com/

    Many times it's about what values they come in and the big one is; will they physically fit in the space provided?

    Have fun the results speak for themselves.

    H9
    "Appreciation of audio is a completely subjective human experience. Measurements can provide a measure of insight, but are no substitute for human judgment. Why are we looking to reduce a subjective experience to objective criteria anyway? The subtleties of music and audio reproduction are for those who appreciate it. Differentiation by numbers is for those who do not".--Nelson Pass Pass Labs XA25 | EE Avant Pre | EE Mini Max Supreme DAC | MIT Shotgun S1 | Pangea AC14SE MKII | Legend L600 | BlueSound Node 3 - Tubes add soul!
  • FTGV
    FTGV Posts: 3,649
    edited August 2010

    In steps the Burson Audio dual HD op-amp upgrade.
    Interesting, are the opamps in the low pass filter/output section or the current to voltage conversion?If the former is the tube used just as a follower(buffer) after the opamps? does this DAC give the option of using either the direct output from the opamps or the tube?
    ...I'm still on the fence about replacing the stock caps ...
    Are the stock caps film's or electrolytics?
    heiney9 wrote: »
    I bought the Burson op-amp regulators for my Adcom dac.
    Cool,are they installed?
    I would have used Auricaps in the coupling position ...
    The 600 is directly coupled.
  • FTGV
    FTGV Posts: 3,649
    edited August 2010
    Not being familiar with the product for **** and giggles I googled it and found a review with pics.I see it's a nah on the option of tube or SS output,it's tube only.Too bad because with a discrete opamp of the quality of the Burson's I would wan't the option of bypassing the tube to hear Burson's directly.
    As for output coupling caps it appears there are a pair generic looking axial leaded films.
  • heiney9
    heiney9 Posts: 25,165
    edited August 2010
    Fred, I haven't gotten around to putting the Burson regulators in yet. In the Fall when things slow down I'll jump into that project and a few others. :)

    H9
    "Appreciation of audio is a completely subjective human experience. Measurements can provide a measure of insight, but are no substitute for human judgment. Why are we looking to reduce a subjective experience to objective criteria anyway? The subtleties of music and audio reproduction are for those who appreciate it. Differentiation by numbers is for those who do not".--Nelson Pass Pass Labs XA25 | EE Avant Pre | EE Mini Max Supreme DAC | MIT Shotgun S1 | Pangea AC14SE MKII | Legend L600 | BlueSound Node 3 - Tubes add soul!
  • Face
    Face Posts: 14,340
    edited August 2010
    Phil, what kind of sound are you looking for?
    "He who fights with monsters should look to it that he himself does not become a monster. And when you gaze long into an abyss the abyss also gazes into you." Friedrich Nietzsche
  • pearsall001
    pearsall001 Posts: 5,068
    edited August 2010
    Face wrote: »
    Phil, what kind of sound are you looking for?

    I was always partial to a warm, laid back sound. But not at the expense of giving up tonal accuracy & tight accurate bass. I take it that your cap suggestion will be based on my listening preference.
    "2 Channel & 11.2 HT "Two Channel:Magnepan LRSSchiit Audio Freya S - SS preConsonance Ref 50 - Tube preParasound HALO A21+ 2 channel ampBluesound NODE 2i streameriFi NEO iDSD DAC Oppo BDP-93KEF KC62 sub Home Theater:Full blown 11.2 set up.