Review of Topping D50s, D70s and a tribute to EMU 0404 USB.

Hello and welcome to whatishifi blog.

Regular blog readers (if there is such a thing for my humble blog), know that since I discovered computer audio, I have chosen to use as a USB DAC a tweaked EMU 0404 USB with a custom made power supply plugged at a PS Audio P300 regenerator. Many years have passed, without finding anything really worth replacing it. Truth is that EMU evolved since I bought it; in the beginning it was tweaked, then I changed the power supply, then the PS Audio regenerator was added. I was about to test a battery PSU in order to replace the current PSU and the regenerator, but I became a bit lazy; even though the battery PSU was made, I didn't find the energy to make a proper blind test. I guess that I was lacking motive, you see from what I had experienced, the question that would be answered with the blind test would be if the battery PSU would be as good as the current PSU / regenerator combo - and I didn't expect any improvement. Of course I could be proved wrong, but things are what they are; the pandemic affects our psychology and I was not very enthusiast in order to proceed with my testing

A little more than a year ago me and Panos were discussing the issue of converting DSD files to PCM through Foobar, in order for the EMU to be able to reproduce them; you see, the EMU 0404 USB is a PCM only DAC. Not that we had any problems or complaints, DSD files were sounding great and in most cases better than the FLAC version for the albums that we had in both formats. We were just wondering if this process decreases the sound quality - as always with Hi-Fi, opinions would vary on this. I remember that we found a nice convenient list with virtually all the DACs available. Panos spotted the Topping D50s, the very same custom made battery PSU he had for the EMU could also be used with it, he took the blessing from our tech guru - the one that opened our eyes regarding computer audio and the EMU in particular - so he purchased it.

The order was placed end of November 2020, the item was available, but the Greek post worked it's magic so the DAC arrived mid of February 2021. We were both very curious to find out if we would face a new apocalypses regarding sound quality, so we unplugged the EMU and started listening to the D50s, connected to the same battery PSU he had for the EMU. In the beginning we couldn't for sure understand if there was any difference. The time needed between exchanging the DACs and adjusting the volume is not allowing an objective testing. So we proceeded with some convenient, on the fly A/B blind tastings; we recorded some tracks from the analogue output of both the Topping and the EMU, taking extra care to record them at exactly the same level. As usual, one of us would listen without knowing if what he is listening to comes from the EMU or the Topping and the other would assist him changing the track back and forth at the listener's command. We included both DSD and FLAC, hi-res and CD quality, jazz and rock. The outcome was not very clear, sometimes we preferred the EMU, sometimes the Topping, sometimes we couldn't hear or feel any difference. Maybe we preferred the Topping just a little more often than the EMU but still, nothing worth of advising somebody who already has the EMU to upgrade it with the D50s.

Now that I think of it, this was already a success; I mean, we had a tweaked EMU and a standard Topping which could perform out of the box wonderfully, without any tweaking.

Of course, we had plans for the D50s so Panos designed and 3D printed a base that would increase the internal space of the DAC, so our tech guru would have the freedom to experiment and do any possible tweaking. Eventually what he did was to add some caps at various power supply sections and the Topping took the place of EMU at Pano's system.

The tweaked Topping D50s

For quite some months we were discussing to repeat the recordings and the blind A/B testing now that the Topping was tweaked, but we were lazy. It is mostly my fault; I didn't expect much, I wasn't eager to upgrade my EMU; after all I was listening to the Topping at Pano's system but wasn't feeling that the music was coming better than the EMU. In the meanwhile, Panos started playing with various OP amps inside the Topping (the LME49720 that the D50s has from factory, is sitting on an OP amp socket for easy change), so the recordings and the blind testing was limited to spotting differences between the OP amps, performed all at his house and his system. We couldn't spot any differences, some more months passed, I became un-lazy, so time had come for more experiments.

Since my main question was if it would be worth for me to upgrade the EMU, Panos brought his D50s at my house, to check it at my system. At that point, the tweaking of D50s had evolved and finished. Our tech guru had strongly suggested to replace the LME49720 with nothing else but two OPA627 (plus the necessary 2 SMD to 1 TTH adapter, since the OPA627 is mono and Mouser had only SMD version available). So we did, but up to that point we hadn't conducted any testing regarding the effect that this particular OPA had on sound quality. Anyway, by using a Sony DTC-59ES DAT with Super Bit Mapping as an ADC and an Alesys Masterlink ML-9600 as a HDD recorder, we performed a new A/B blind testing. The track that we used was Limehouse Blues from the 2xHD DSD album Jazz At The Pawn Shop, with strategically inserted marks that helped us to navigate at certain parts of the song at the press of a button. As always, we took extra care so that the rec level of both recordings would be equal.

After some listening tests, we both preferred the recording coming from the Topping, mostly due to a more clear layering and focus at the 3D sound stage. The difference was not big, but it was clearly noticeable and anticipated.

Even though I could keep on living with the EMU, I took the decision for an upgrade, partially due to sound improvement and partially due to the joy of upgrading to something new. In the meanwhile, there was a new understanding regarding the PSU of the DAC I would choose. Up to that point I was limiting myself to DACs that have a 5V input, in order to keep using the good existing PSU I had for the EMU. However, I hadn't realized a compromise; not every circuit inside the DAC works with 5V, some parts of the circuit need higher voltage and this is done by using small switching-mode power supply modules. Having already the safety net of the PS Audio P300 regenerator, I decided to expand the candidate models with ones that get a direct 230VAC feed. After a small discussion with our tech guru, I decided to go ahead for the Topping D70s, liking the linear power supply and the AKM chips. My other candidates were the D50s and the RME ADI-2, which let me point out that it no longer comes with the AKM chip, now it has ESS - you can read an interesting sound comparison between the two versions of this DAC here.

So I was lucky enough to find a D70s available - after the fire at the AKM factory DACs using AKM chips are in shortage - I ordered it and a few days later arrived. Panos came to assist me with the installation and we immediately started a listening session. After a short while, things were disappointing to say the least. Sound was harsh, lacking emotions. OK, I could spot some goodness in it regarding a beautiful soundstage, but overall listening to it was not pleasant. I listened and listened over again; I kept feeling that this was a bad decision and I should sell the DAC and get the D50s instead. I tried the various filter settings, but to be honest I couldn't make a safe conclusion. Feeling desperate I also brought the D70s at Pano's house, to give it a listen at another system trying to understand if the D70s was sounding bad or if there was a bad synergy at my system. Things were equally bad, the Analogue Productions excellent recording of The Girl From Ipanema was sounding boomy and was lacking all the warmth we knew this recording has.

The Toppimg D70s with the protective sticker still on the display; at that point I thought I should sell it.

Panos was advising some burn in, I was also considering it but I couldn't imagine that this could really help, because the damn thing was sounding really aggressive. Not having a problem to accept that buying the D70s was a bad decision, I started searching deeper at the web, since all the reviews for this DAC were positive. After a while, I found another user that had experienced same issues with me, with phrases like "Sounds great, very clear. Yet annoying", "it’s too bright for me going into the Sansui, also too much bass" & "When I first opened it out of the box and plugged it in, it was awful. Extremely harsh, metallic and blinding in most instances. I could not last more than a few songs before wanting to turn it off, leave the room, then go re-evaluate the day. Sure I could hear the top hat, but it had a sodium spotlight blazing on it" being spot on of how I felt. But in the end, after letting it play for some days, the same user was reporting that things became normal: "With it now burned in, the cringe factor is gone". So, it seems that there is light at the end of the tunnel. After all, I had nothing to lose by waiting for some burn in.

Apart from the burn in, I also ground lifted the DAC and upgraded the firmware. (Be aware that a firmware upgrade will set the output level at full, in case you are using it at the DAC + pre amp mode). Desperate and sad as I was with my purchase, I can't know if this also helped. But now I am sure, the D70s absolutely needs to burn in for at least a full couple of days before making up your mind about it. If I knew it from the beginning, I would have avoided some headache and I would have also kept a recording to compare it later, since this burn in thing includes some vague mystery; after all, why is it that things can become only better with burn in and not worse?

 

During the burn in period, I could clearly hear things evolving. Listening was becoming more and more pleasant. At songs that I have heard many times, I started noticing tunes that I hadn't noticed before. The inner rhythm of the songs was communicated in a better way to the listener. The soundstage was amazing. In the beginning the sound was too analytical, like the DAC was deconstructing the recording, but as time was passing by, everything sounded as a whole without losing detail, like all the ingredients of a food blending together at a good recipe.

Next thing after the burn in was to make a recording so we can safely compare the sound of the D70s with the sound of the tweaked EMU and the tweaked D50s. Being lazy again, some months passed by (and in the meanwhile, finding a new D70s is virtually impossible, making this post somehow obsolete) but eventually the recording was made and we started the blind test procedure. We couldn't say that the one was better than the other. The tweaked D50s is offering same level of performance like the factory D70s.

So, if you can tweak a D50s and have access to a top quality power supply, this will cost you less and offer same performance. If you need something out of the box to play with, then get a D70s. EMU is still a good choice for a low budget; it can be found used at around 50 Euro but it will need a sophisticated PSU in order to perform at full potential. Regarding MQA (only the D70s supports it) I wouldn't bother, but hey, it's just me.

Last but not least, seems like there is no reason of limiting your choices based at the ESS Vs AKM hype; what it really matters regarding the sound quality is the overall design of a DAC.

Of course, there is now another question; can the D70s be tweaked in order to get a performance boost? It will take some time to answer this question since enough is enough with testing, now it is time to enjoy some music!

As always, happy listening!

Christos