Measurement and Review of Burson Play DAC & Headphone Amplifier

[Jimster480]

Pretty nice images man, they should make it like that from the factory honestly.
A few flaws make an otherwise great unit.... unlikely to sell well.

Maybe they can change it for the future

 

[trl]

I was able to get a couple of double-shielded cables immediately after the Low-Pass opamp and after adding in series a couple of 50kOhms resistors I got perfect unity gain, which is quite great actually, because there's no analog volume knob between the amplifier.

I found the output impedance of being around 700 ohms which kinda not perfect, because when I attached a signal generator or an external DAC the 2V RMS dropped to about 1.5-1.6V RMS; however, if I'll find a better way to "inject" audio signal into PLAY's internal amplifier then I'll post back here.

Meanwhile, I got perfect results for this Class-A amplifier that proves that "no cap is best cap"!

DUT: BURSON Play DYI amplifier's input (between the LPF and pre-amplifier opamps).
Scope: PicoScope 2204A.
Channel A (blue) is the input signal.
Channel B (red) is the headphone 6.3mm jack of the amplifier.

10 Hz sine-wave

100 kHz sine-wave

10 Hz square-wave

1 kHz square-wave

20 kHz square-wave

50 kHz square-wave

Sorry for not having a better square-wave generator; I've used the one included in my scope.

 

[Jimster480]

Is that actually a good device for testing? It looks like its only analog?

 

[trl]

Besides having only 8-bit and 50mV resolution on the lowest scale I find it quite good for what I need. However, I'd like to have a 10-bit scope or even more, but this one suits my needs.

 

[amirm]

Is that actually a good device for testing? It looks like its only analog?

Scopes are made for high-speed operation (well above audio band) and hence, their analog to digital converter has much lower depth/resolution. Even very expensive ones can't rival a simple sound card in bit depth. Even "12 bits" is a huge deal in scopes which for audio is not useful at all.

Trl was making other types of measurements like showing gain and there, it is fine. But it can't be used for much to replace the types of audio measurements we make.

 

[trl]

Awesome review Amir!
The unit is actually on "loan" from me which is on "loan" from Burson who sent it to me for me to review it.

Glad to have measurements from it, I shared the link with Burson now!

You should be getting the new PCB revision for 99$ and swap the old one. I'm expecting an increase in resolution from 16-bit up to 19-bit as per BURSON's modifications:
- increasing the ground-plane to entire PCB size (in the older revision the ground-plane was covering 50% of the PCB: the boost converters and the DAC area)
- adding a huge number of PCB joints between the ground-plane and the upper copper layer
- SMPS boost-converters have been swapped with different sub-models
- adding about 20 x through-the-hall polarised caps around power regulators (boost converters), around the I/V stage and also around the output stage and the pre-amp op-amps
- adding several SMD caps across the board

A pic showing the differences could be found here, from a fellow head-fier: https://cdn.head-fi.org/a/10094905.png.
Head-fiers already stated that background noise is inexistent on their sensitive cans now. However, I'm expecting my new board within few weeks to confirm that.

P.S.: At this moment I'm using the old PCB revision powered through a DIY external LPSU and on the RCA-out there is no noise perceived with 16-ohms IEM cans, volume to the max or min makes no difference. DAC is not getting into mute, because playing a dithered -110dB file is not increasing the background noise. Noise test conducted with Superlux 16-ohms IEM and Objective2 @3.7X gain. Max. possible volume @RCA-outputs would be 4.5V RMS x 3.7 = about 16V RMS! So quite a very good dynamic range I'd say, as this DAC is probably set for 4.5V RMS output instead of 2V RMS (Quite a dangerous background test, given the fact that a very small beep or click coming from RCA-out could make me deaf for life!).

 

[trl]

The new PCB revision v2.2 contains 20 more ELNA polarised capacitors and the ground plane has increased to about entire PCB, even nearby the output stage transistors. Also, DC-DC regulators were replaced too.

Background noise when using 32-ohms cans was virtually removed, well...with my very sensitive 16-ohms IEMs I can still hear something if the room is totally silent, but honestly...for $299 I can't think to a better combo having at least half of PLAY's power.

Also, this combo is so good for modding, probably this is why I love it so much...

 

[Jimster480]

View attachment 12900

The new PCB revision v2.2 contains 20 more ELNA polarised capacitors and the ground plane has increased to about entire PCB, even nearby the output stage transistors. Also, DC-DC regulators were replaced too.

Background noise when using 32-ohms cans was virtually removed, well...with my very sensitive 16-ohms IEMs I can still hear something if the room is totally silent, but honestly...for $299 I can't think to a better combo having at least half of PLAY's power.

Also, this combo is so good for modding, probably this is why I love it so much...

The power is entirely un-needed.
Unless they have fixed the amplified outputs and the power supply running super hot... There is no improvement.

 

[trl]

Well, the background noise when using sensitive cans has been settled down.
Meanwhile: https://audiosciencereview.com/forum/index.php?threads/burson-play-mods.3346/

 

[trl]

Headfonia was able to test both ver. of PLAY here: https://www.headfonia.com/review-burson-play/3/.

I assume they were testing boards revisions V1.6 and V2.2, which I already own myself and I was able to get the background noise difference instantly with 16 ohms IEMs, but also with some really sensitive 32 ohms cans like: AKG K550, Beats Solo2 and even with Grado SR60i if really quite environment. If my ears can feel the 3-4 dB difference between the two motherboard revisions, then these 3-4 dB in SNR really means something indeed.

However, while A/B-ing between the new revision V2.2 with 1 x standard SMPS PSU and onboard power regulators vs. the old board revision V1.6, but with 3 x external linear PSUs (original power regulators unsoldered) I was able to get a SNR improvement on the V1.6 with linear PSUs over the newer V2.2 board in original version.

 

[lardyl]

Sorry to go necro on this but does anyone know if there are harmony codes for the remote control for the Play? I've ordered one of their end of line units for $199 USD and it comes without the remote. Cheers, Ian

 

[trl]

Logitech Harmony seems to be self-learning remote, if you can borrow one and try it out might help.

I have PLAY and it's remote control, just not sure how to find out the codes. I'm thinking on using a video camera with slow motion (120fps), then try counting the codes per second, but AFAIK these are pulse code modulation. I might also check with my scope the serial transmission, but I don't really have experience with interpreting remote codes, so....if anyone has an idea how to find them out, please let me know and I'll see if I can help.

How does it pairs with your headphones? How do you find the sound?

BTW, if you have the default NE5532/5534 opamps installed, you might want to try 3xOPA1612 or 3xMUSES8920for I/V and LPF, and 2xAD797 in front of the output stage. Although, you might not get a more musical sounding, but background noise may decrease with 1-2dB (only helpful with sensitive IEMs).

 

[amirm]

Should ask the company for the codes and then supply that to Logitech.

 

[lardyl]

Thanks guys, I believe that I've got the later version of the unit as it switches the line output on when the headphones are disconnected (well when the TRS adapter is pulled out).

I'm currently in discussion with Burson as the mute switch has stopped working within a couple of days of receipt of the amplifier.

I'm using Sennheiser HD-540 Ref IIs and Alessandro MS-1s to listen along with some Musical Fidelity monoblocs and a Chinese class D amp with my Castle Sterling speakers.

 

[lardyl]

OK Burson Customer Service has been very good so far, very prompt responses and good comms. They've offered to mail out user serviceable parts to do a repair on the volume control, it's a board swap so I am told.

Burson have also advised that the IR codes for the Play are standard NEC ones, I've used my old Harmony remote to try and get the three codes, "Vol+ / Vol- / mute" with mixed results, can't find a code set that does Vol- but have a couple that do Vol+ and Mute.

For anyone that's interested this is an NEC code for NEC DVD VCR (NDT-43)

Vol+ = VCR5
Mute = VCR1
Vol- = ????

 

[trl]

It is a NEC chip inside the remote, for sure, thanks for letting us know the correct codes.

If you need to replace the rotary volume knob, you'll need force and attention to remove the plastic knob.

I'm glad this is sorted out for you now.

 

[lardyl]

Thanks. I liked this so much that I bought a Bang to replace my old Musical Fideilty X-A50 monoblocs and it sounds great.

Not got round to changing the volume control board yet. I've indulged in some Massdrop V5i dual op amps and was wondering if I might see any improvement on the pre-out sound to the bang by changing one/two of the dual op amps in the Play?

I can see there are 2 single channel and 3 dual channel op-amps but which deal with what?

I could refer to TRL's nice photo above as a guide. Cheers

 

[trl]

BANG is small and powerful enough for a small bedroom when driving normal sensitivity speakers (88-90dB/W@1m). For fitting inside a well-ventilated computer case, perhaps BANG is #1 at this moment.

X-A50 are more powerful and, being monoblocks, crosstalk might be better (at least theoretically). I think these 2 amp belong to separate use-cases after all, given the power differences and their different sizes.

In the end, all it matters is the please our ears with enough power delivery, low-enough THD and no overheating and no oscillations.

As for the PLAY, do not place V5i inside, please; they might be noisier and also unstable. Default JRC5532DD should do just fine. If you're really-really into opamp rolling, then 3xMUSES8920 + 2xAD797 will lower the noisefloor a little bit and decrease the THD, but not sure you will hear the difference with your headphones. If you like DIY, 3xAD8599 soldered onto DIP8 sockets will also be a good upgrade.

P.S.: I think I measured THD+N with several opamps, not sure I can find the pics...

 

[lardyl]

Thanks for the advice, I have the Bang driven by the Play into my old Castle Sterling 3 floorstanders, published at 91dB/watt. The Play at 20 on the output dial does more than fill the room with sound. Stock PSUs and nothing else going on.

Used to run my X-A50s as part of a bi-amp system with my lovely old X-A2 integrated amp. Both the X-A2 and one of the X-A50s were taken out by the dirty mains at our place, along with another X-A50 that I used in a surround sound system. We are two doors down from a garage workshop where I suspect their welding work has screwed the mains in my house. I've lost other PSUs (linear and SMPS) as well as the toroidal transformers on these three amps, one from a desktop workstation and several plug-in transformers over the past two years.

Most of this gear survived for decades in other houses beforehand.... sigh.....

Could be wrong but these failures all happening within a few months leaves me to suspect the supply.

 

[trl]

Might worth checking if BANG is set to lowest gain, just need to open it up and swap the two gain switches till you get the lowest amplification (maybe adjusting the dip-switches while powered off would be wiser).

You are an extremely valuable ASR member, due to the fact that you have such a poor and noisy mains (sorry for that), hence you're one of the best tester for "audio power re-generators", power conditioners, online UPS and, why not, AVR/stabilizers.

Now, seriously, a relay-based AVR shouldn't be expensive, an it might provide you a basic protection for your audio devices. Something around 1000-1500VA should handle PLAY + BANG + 2 x X-A50S without issues. Just take care to not overload AVR (e.g.: 1000VA = 660W, that means max. continuous power handled shouldn't be higher than 500W).

P.S.: Schneider iMSU (or similar devices) combined with a good RCCB should also help with your home appliances.