Burl B2 Bomber DAC Review: Holy Sh**, This is Good

Discussion in 'Digital: DACs, USB converters, decrapifiers' started by purr1n, Jul 14, 2020.

  1. Gungrave

    Gungrave Rando

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    Any updates on the burl bopa8 ?? Is it still narrow soundstage ?!?
     
  2. Clemmaster

    Clemmaster Friend

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    No, it expanded to where it was before.

    Depth is still better, and so is focus. It's not quite as sharp as it was out of the box.

    I've been listening to the Rockna pretty much exclusively the past week, though. That's a sign.
     
  3. beemerphile

    beemerphile Friend

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    Do we need to change our FOTM sign? This one is going to be expensive!
     
  4. Clemmaster

    Clemmaster Friend

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    Switch back to the BOPA1, after running the BOPA8 for over a week.

    I maintain what I said in my first impressions. BOPA8 is clearly more 3D, sharp and incisive and better in the technical aspects of sound reproduction, but it loses some of that magic "Burl tone".
    I bet many would give the latter up for all the improvements, though.

    Coming from the BOPA1, I would recommend the upgrade, unless (for some reason) the sound is already on the incisive side in the system.
    For those who already have the BOPA8, I would only recommend the BOPA1 if the sound is too sharp/incisive. Even then, you'd be giving up quite a bit.

    BOPA1 is more easy going, slightly rounded.
    BOPA8 is more technical, sharper.

    All the above should be taken with a grain of salt - until confirmed/disproved by @purr1n - as my ears I could very well be full of shit.
     
  5. Collusion

    Collusion Friend

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    A random observation: the original IEC C14 power socket on the Burl has an inbuilt EMI filter. Replacing it with a standard off-the-self part worsens the sound quality by a little bit: now everything sounds marginally more sizzly, even if the unit is powered directly from a Furman AC-210E power conditioner. Maybe the unit bleeds back into the power line without the filter? I've got my SPL preamplifier in the same power outlet.

    If you are wondering how I came up with an idea to switch it to an another, it's simply because snap-in mount gave up and the power socket won't stay put anymore. It seems there's no easy way to re-attach it anymore (at least one that won't look like an obvious DIY solution).

    The original part is manufactured by Te Connectivity / Corcom and goes by the part number of 3EAS1. Instead of the original inlet I've planned to replace it with a 3EEA1 instead - it has an external mounting flange and similar enough electrical characteristics.

    20200828_200757.jpg

    20200828_205322.jpg

    3eea1.png
     
    Last edited: Aug 30, 2020
  6. Gungrave

    Gungrave Rando

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    hear ye, hear ye ! we await @purr1n First Impressions and Final Judgement !
     
  7. bixby

    bixby Friend

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    These input filters can make quite the difference.

    An elec engineer friend had modded a mid priced chifi tube preamp. It sounded good but one of the last things he tried weeks later was a ground choke on the input power ground. We had all gathered at my friends place and heard the preamp for many tracks then let the ee solder in the choke real time.

    And then we listened again. Yes! better. Placebo? maybe but I think it helped. Cost a whopping $5 plus freight.

    https://www.mouser.com/ProductDetail/Schurter/DENO-25-0001/?qs=A5k8bsa1loDfpdVSyZOXZg==
     
    Last edited: Oct 15, 2020
  8. FreezerBurn

    FreezerBurn Rando

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    I have a Burl B2 Bomber DAC and have been listening to it since December 2018 using Dante with the BOPA1 and have upgraded to the BOPA8 by calling Burl and ordering a pair. I'll say your observation is pretty close to mine. The BOPA8 needed a little break in time but it does have more depth and is sharper. It changes the attitude of the DAC by quite a bit for the better I think. Still the BOPA1 did sound much warmer or saturated if that's the word, but while it did sound great still in comparison to the BOPA8 audio images were better defined and effects crackled with texture better than the BOPA1 at -10 or -12.

    I've found the Dante Via to be a pretty great sounding way to send Dante signal in Windows 10 to the D/A, I have the performance slider all the way up, and it works on 48khz. For some strange reason I might prefer it to the WASAPI driver, not just cause I don't need to manually change the sample rate all the time but maybe cleaner jitter? (I'm not sure if it's jitter) either way I've been really enjoying the B2 DAC. I've wondered if an external clock is worth a try, Will at Burl advised against it, maybe I should just chill and enjoy the music longer.

    Windows 10 Pro -Dante-> Burl B2 Bomber (BOPA8) -XLRtoRCA(float pin 3)-> ATC CA2 mkii -XLR-> ATC P2 amp -10gauge Monoprice-> Magnepan 1.7i
     
    Last edited: Dec 7, 2020
  9. penguins

    penguins Friend, formerly known as fp627

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    Borrowing from @Clemmaster - wasn't going to say anything at first, but initial impressions after about 1.5hr of warmup and 15 min of listening - wow... this thing is good. Will refrain from reading too much of the other posts above for now.

    It has a pretty different sound from pretty much most of the DACs that have been mentioned here, including the R2R stuff, a few of the more pro audio oriented DACs (CS Solaris loaner, DM Convert 2 w/ the brief listening I had, Bricasti M3 loaner) and some of the other more popular consumer stuff (ADI2, Chord, iFi, etc.).

    Summary of the sound - this is super cheesy, but in short this DAC was aptly named - it feels like it's trying to bomb you with a lot of sound at once... but not so much that things get completely obliterated - else this would be a B52 or Tupolev, not just a B2. Certain parts of the sound seem to be deliberately exaggerated, more prominent, and slightly distorted at times... but not in a "this is lo-fi" way. This DAC won't be for everyone and it can be a bit much on some tracks. But still very good.

    Will share more later after more listening.
     
  10. Clemmaster

    Clemmaster Friend

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    @penguins : did you leave the BOPA-8 in?

    Most of the previous impressions were with the original BOPA-1.

    Also, it’s worth setting up Dante on your source (if possible) and set the DAC to internal clock ;)
     
  11. penguins

    penguins Friend, formerly known as fp627

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    BOPA-8 and tos input for the B2 and EC AF for amp. Will setup Dante later this week when time permits but I’m already excited for it. Stellaris will come later this week as well.
     
  12. penguins

    penguins Friend, formerly known as fp627

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    Update after a little more time with the B2.

    Disclaimer: I was busier than expected the last 1.5 weeks and somehow, this DAC was a bit harder for me to properly characterize vs most other DACs I've heard. Hence, this isn't my best review ever, but I'm proceeding with it while it's still fresh in my mind.

    SUMMARY:
    My opinion hasn't changed, this is a very good DAC. Definitely deserves the SBAF 2020 SD award that it won. It has a very clear and clean sound unless you pushed the circuitry inside - then the sound was slightly distorted (many of you know this is common with electronics though). Very hard hitting as mentioned above. After a little more listening, I realized my initial comment "Certain parts of the sound seem to be deliberately exaggerated, more prominent..." from above was just because of the hard hitting nature.

    If you don't have a problem with hard hitting, then very similar to the 2541, I didn't really hear any real problems with the sound. However, because this DAC hits hard, I would imagine that for most, myself included, synergy is even more important here than most of the popular SBAF DACs and you will need to invest some time in finding a setup that works for you. Keep in mind that although this DAC is hard hitting, it does NOT sound artificial or exaggerated like the Convert2 does to me at times. More amazingly, I did not have any listening fatigue after 4 hours of listening with HE6se despite both being hard hitters.

    Also, this DAC does not fix or make aspects of the sound "more palate-able" for you. I don't really know how to describe it any better, but when I heard the Morpheus, Yggdrasil, or the 2541, they seemed to do this to some degree. The CS Solaris and this DAC do not. Not that the first set of DACs horribly distort the music or make it too bloomy, too unrealistic, etc... just that they somehow clean the sound up slightly whereas these 2 don't.

    SETUP:
    Did not roll to BOPA-1 op amp as I was busier than expected last and this week. pi2aes / optical / started fiddling with Dante (built in network streamer) but there seems to be a software issue and I haven't had enough time to troubleshoot yet and may not get to it before I have to return it to Clemmaster. BAL to SE transformers as needed as B2 only has BAL out and my current headphones.

    SOUND:
    - Resolution and detail retrieval - Good, maybe at about same level as 2541 to me if I really listen for it, but because this hits hard, it could get lost if you didn't specifically listen for it. Same story with the plankton - it's there, but you have to listen for it. Regardless, it is not at the level of a Yggdrasil or other "very resolving" DAC (although Burl did a good job considering there is only 1 AKM chip inside).
    - Macrodynamics - as mentioned, if you up the volume knob on the DAC and play songs with BIG swings or BIG drops, those will be a little distorted as I suspect the op-amps or some other component/s are being pushed close to their limits (the "no distortion limit", not like a safe operating limit). There also seems to be something else going on beyond a mild distortion when the volume is pushed - not quite sure how to describe it though. Despite this distortion, I didn't hear noticeable clipping.
    - Stage - Big to the point where I mostly forgot about staging in a very good way. However, it's not artificially expanded and things do not get artificially separated or lost. No vague zones or blobs or wrap around weird shapes.
    - Layering - OK with optical in, better with AES in. Dante pending. Not the best I've heard, but good.
    - Transients - Clean, relatively crisp. Probably 5.5/10 speed. Also, although this DAC hits hard, transients are properly tamed and are not overshot or artificially cut short, etc.
    - Texture - Slightly lacking, but not bad. It may have been there and I just don't know how to hear it in the hard hitting sound.
    - Nothing wrong with highs, mids, lows, tonality, timbre, or other sonic traits we often talk about here. No issues with busy music.
    - There may have been a slight warmth to the sound
    - I don't know how to describe this properly, but although there wasn't a thick sound or poorly separated lows, the lows definitely sounded more "full". Add-on: OK, went back and read the other impressions now and I see on the first page Purrin mentions saturation or a vintage saturated sound. I suspect I'm hearing the same thing and this is the same thing I heard in the above "macrodynamics" section when the DAC is pushed. I'm generally a quieter listener though so this didn't happen too much for me.
    - Regarding the hard hitting - it's more at the beginning of any note, but as mentioned above, it doesn't overshoot, become artificially loud, ring excessively, etc. It just somehow sounds more "there".

    OTHER:
    - I see on the first page that this DAC is supposed to run hot. It didn't get hot at all for me even, after 4+ hours of continuous listening. The hottest part was about as warm as or a little less than the outside of my Yggdrasil (sorry, I don't have FLIR). Not sure if this is due to BOPA-8 vs BOPA-1 op amps. My setup was placing a ream of printer paper on top of a desk and then putting this DAC on top of the printer paper. Proceed with caution and monitor temperature of gear regularly anyways, don't fry your gear via negligence.

    SYNERGIES - Keep in mind that while I am trying to speak in generalities and not only per my preferences, I am inevitably going to be biased here:
    - I didn't like my Autuers and the little I heard from other ZMFs with this DAC regardless of amp used. In short, they lost their ZMF magic and all of the weaknesses of the headphone seemed to come out. My guess is the strong initial attacks unique to this DAC may have screwed up something with the driver / wood cup interface that's mostly unique to ZMF. Focals were great. Everything else varied per setup, song, etc.
    - Most synergy with amps was surprisingly the SW51. EC Ultralinear (only briefly) and Cavalli LC were not bad either. I would want to hear this with a 3F if possible, I am guessing that would be a very good combo.
     
    Last edited: Feb 10, 2021
  13. purr1n

    purr1n Burned out

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    Like you, I found the sound of this DAC very difficult to describe. It's not a tour de-force in terms of technicalities and it's not a impressionist painting DAC.

    It just simply sounds fun and gud - and normal enough to work on music with.
     
    Last edited: Feb 11, 2021
  14. CEE TEE

    CEE TEE MOT: NITSCH

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    OK, I bought a pretty beat up, early B2 with both BOPA1 & BOPA8 cards. This one is Rev. B. The trimpots are internal rather than accessible from the back.

    Using my finally fixed 2nd Balancing Act. (Tubes: EML PX4 Mesh, TSBGRP driver).

    PROBLEM with BOPA1 cards: After a little while, BOPA1 starts to really distort (unlistenable).
    Pi2AES > AES > Burl > BOPA1 > Clock Source AES1 > BA > modded HD800

    Right now I am testing the BOPA8: Not having the same issues so far. I can change output levels and play louder with no real issue.

    BOPA8 is a little tighter/drier sounding but keeps signal integrity. I really like the BOPA1 sound (when it works) for a little while at start-up.

    Wondering if I have some kind of issue with the BOPA1 cards or interaction between BOPA1 and Balancing Act input impedance.

    Could I have an issue with the Burl BOPA1 into the 15K Penny&Giles Pot?
    I wonder if the new BOPA8 output cards were designed to play better with a greater range of input impedances.

    If anyone has any thoughts- thank you!

    My next step is to roll the BOPA1 back in and see if I can replicate issue after the BOPA8 work well for the rest of tonight and after a separate BOPA8 session tomorrow.
     
  15. Cspirou

    Cspirou They call me Sparky

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    I would think that pro DACs would be able to drive 10k loads or lower.
     
  16. CEE TEE

    CEE TEE MOT: NITSCH

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    Thanks @Cspirou . I'll keep working on it.

    Mostly all good: Super happy with my tube amps fixed and running well, the Burl Company is actually close to me, & the BOPA8 cards are working fine. So if this is the worst case scenario, I still got a great deal on the DAC and like the space and sound.

    Home and office rigs complete! :eek:
     
  17. Josh Schor

    Josh Schor Friend

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    Does anyone have a b2 bomber they could lend me? Really want to try it out to see if its my cup of tea. I only have USB output from my music server so would need to get a convertor.
    best,
    Josh
     
  18. CEE TEE

    CEE TEE MOT: NITSCH

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    ^Someone has my Burl right now...next it goes to Marv and then I think it goes on loaner @Josh Schor .
    Please keep an eye out and I will remember you asked for it.
     
  19. Josh Schor

    Josh Schor Friend

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    thank you, would love to hear this with my rig. Do you have any suggestions on what to get and how to use my USB only my music computer. Which input is best and how to do that.
    best,
    Josh
     
  20. Josh Schor

    Josh Schor Friend

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    I'm going to try this dac, my music computer is USB out only, appreciate suggestions on best sounding device to use and which inputs to use from all of you who have used it
    Josh
     

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