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SMSL RAW Pro-DAC1 Balanced DAC Review
- Thread starter amirm
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Bo Dacious
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What are the differences between the RAW Pro DAC-1 ans the SMSL SU-X? Has anyone compared the sound?
Roland68
Major Contributor
The RAW Pro-DAC-1 uses an ES9039MS PRO, and the SU-X has two ES9039MS PRO DAC chips.
The RAW Pro-DAC-1 uses switching power supplies, while the SU-X uses transformers. In the past, I wouldn't have owned audio devices with SMPS; today, I'm very skeptical of such devices with transformers.
The RAW Pro-DAC1 has a high-quality housing and is likely identical to the usual suspects: the SMSL DO400, DL400, Loxjie D40 Pro, and D60. The devices differ in their housings and displays, and, unlike the RAW Pro-DAC1, they have a very good, high-quality, true balanced headphone amplifier with 4.4 watts.
In Amir's test, the Loxjie D40 Pro had a SINAD 0.1 lower than the RAW Pro-DAC1, i.e., 123.3 versus 123.2. This is more due to device variation or measurement inaccuracy than to any real difference.
The Loxjie D40 Pro is currently available at Amazon.de for €319.99. The money saved would probably be much better spent on headphones or speakers, as you won't find any difference in sound compared to the RAW Pro-DAC-1 or SU-X.
We conducted a very complex blind comparison with several people, including the SU-10, SU-X, DO400 (identical to the Loxjie D40 Pro), and so on, and there were virtually no differences in sound or anything attributable to one device. Especially not better or worse.
antcollinet
Grand Contributor
They are both audbly perfect : Any errors are below the level of the human ear to detect.
They will both sound the same.
Decide based on price and features. Don't worry about the sound.
nanook
Senior Member
@amirm:
Thanks a lot for the review. Indeed a very nice piece of equipment.
Since this one's based on the AK4499EX I assume there are the usual parameters to choose from: clock frequency (5.6 vs 11. 2 MHz as far as I remember) and mode (measurement / sound quality).
Given the excellent THD results, I guess you were using 5.6 MHz and measurement mode?
EDIT: Ignore please. I mixed it up with the non-PRO version. Confusing....
Thanks a lot for the review. Indeed a very nice piece of equipment.
Since this one's based on the AK4499EX I assume there are the usual parameters to choose from: clock frequency (5.6 vs 11. 2 MHz as far as I remember) and mode (measurement / sound quality).
Given the excellent THD results, I guess you were using 5.6 MHz and measurement mode?
EDIT: Ignore please. I mixed it up with the non-PRO version. Confusing....
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I own an SMSL D400 PRO that is based on the same AKM AK4191 (the IC that does oversampling and Delta Sigma modulation) and an AK4499EX, which is the actual digital to analogue converter.
As with your DAC, It has four different "colors".
Most of the time I use Sound Color 2, which runs the D/A IC at 5.6 Mhz, like DSD 128.
For Rock/Pop recordings that are on the bright side, I use Sound Color 3, that gets de D/A IC a 11.2 Mhz, like DSD 256.
I Mostly listen to Hard Rock music (Van Halen are my favourite band) from the 70's, the 80's and some from the 90's, Pop music, mainly from the 80's, and I also listen to orchestral movie soundtracks, mainly by John Williams, Jerry Goldsmith, some Michael Nyman, Enio Morricone (only one, the soundtrack for The Mission on SACD) and some, very little Classical music. Regardless if the movie soundtracks or the Classical music I listen to is on Red Book, 96/24 or 192/24 PCM, or on SACD for this kind of orchestral music I ALWAYS switch to Sound Color 4 that makes the D/A IC rund at 11.2 Mhz (again, as DSD 256), that is how orchestral music sounds the best to my ears.
I don't know what these sound color work as there are two Sound Colors that gets the D/A IC rund at 5.6 Mhz, but these two (1 & 2) sound different. I don't like how Sound Color 1 sounds, despite being the default one.
And the same with Sound Colors 3 & 4. Sound Color 3 sounds great with some bright Rock/Pop music, but Sound Color 4 is great with orchestral music.
Does anybody think that these Sound Colors are just equalization presets? I don't think so.
nanook
Senior Member
These sound color modes are not equalization nor adding harmonics (the latter is what the ESS chip based DACs often offer (just dialing in more or less extreme values for the distortion compensation h2 and h3)).
The AK4499EX offers 2 different frequencies the actual DAC runs at and they offer to choose between "measurement-mode" and "sound quality mode". The latter seems to change the behaviour of the DWA (data weighted averaging) that reduces the nonlinearity and thus distortion.
I had the DO300EX, but decided to return it. I didn't hear a difference between the D6s and the DO300EX and I like the design (and price) of the D6s more.
Moreover to my taste the DO300EX lacks a reasonable lowpass filter; there's a lot of high frequency noise (edit: well outside the audio band above ca. 70 kHz) due to noise shaping present on the XLR output when operated at 5.6MHz and in measurement mode. I could have added a higher order filter in a fully differential I/V stage, but I didn't want to fiddle with a brand new piece of equipment.
edit: I don't think this is relevant for the actual purpose listening to music ; it's rather my perfectionism that asks for improvement - I'm a circuit designer...
The AK4499EX offers 2 different frequencies the actual DAC runs at and they offer to choose between "measurement-mode" and "sound quality mode". The latter seems to change the behaviour of the DWA (data weighted averaging) that reduces the nonlinearity and thus distortion.
I had the DO300EX, but decided to return it. I didn't hear a difference between the D6s and the DO300EX and I like the design (and price) of the D6s more.
Moreover to my taste the DO300EX lacks a reasonable lowpass filter; there's a lot of high frequency noise (edit: well outside the audio band above ca. 70 kHz) due to noise shaping present on the XLR output when operated at 5.6MHz and in measurement mode. I could have added a higher order filter in a fully differential I/V stage, but I didn't want to fiddle with a brand new piece of equipment.
edit: I don't think this is relevant for the actual purpose listening to music ; it's rather my perfectionism that asks for improvement - I'm a circuit designer...
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Thanks for your reply.
And what Sound Colors/working frequencies are "measurement mode" and "sound quality mode"?
nanook
Senior Member
I can look this up when I'm back home mid of April.
The DAC frequency was displayed on the DO300EX and the measurement mode was the default mode (the stunningly low THD is only achieved in measurement mode)
From the manual of the DO300EX:
SOUND COLOR
SOUND 1(5.6M)
SOUND 2(5.6M)
SOUND 3(11M)
SOUND 4(11M)
1 and 3 were measurement mode (rotation of elements in the DWA) as far as I remember.
The DAC frequency was displayed on the DO300EX and the measurement mode was the default mode (the stunningly low THD is only achieved in measurement mode)
From the manual of the DO300EX:
SOUND COLOR
SOUND 1(5.6M)
SOUND 2(5.6M)
SOUND 3(11M)
SOUND 4(11M)
1 and 3 were measurement mode (rotation of elements in the DWA) as far as I remember.
I owned the DO300 EX and I got Amazon to get It exchanged for the more expensive D400 PRO, that for me sounds a bit better than the DO300 EX.
The D400 PRO ALSO shows, if memory serves me well as I'm not at home at the moment (and I won't be until a week or so) but I remember perfectly the different frequencies the D/A IC works depending on its sound color.
I don't like how Sound Color 1 sounds, either with PCM, at Red Book resolution of High Res, or DSD. For Rock/Pop recordings on DSD I mostly use Sound Color 2 and also for PCM, but some PCM recordings sound better to my ears on Sound Color 3 using Short Slow filter. I don't quite like how DSD sounds with Sound Color 3.
But Sound Color 4 is perfect for orchestral music, both with PCM and DSD.
So "Measurement Mode" gives the best results when the DO300 EX or the D400 PRO are tested with equipment like Amir does. But does It mean that with Sound Colors 1 & 2 It may sound better (something that is subjective) despite giving lower distorsion?
Just in case this helps, my humble sound set Up comprises of Sony's UBP X-8OO M2 UHD BD/SACD player, HDMI 2 output connected to "the Chinese HDMI audio extractor (HDMI to I2S for both PCM and DSD and S/PDIF FOR PCM and DSD output as DoP), from that, using I2S, to the D400 Pro. Integrated amp is a Marantz PM 6007, speakers are KEF's Q550 plus a B&W ASW 608 subwoofer. Both speakers and subwoofer are sealed enclosure designs.
For me the change from the DO300 EX to the more expensive D400 PRO is worthwhile. With the D400 PRO I notice better imaging, a bit better low level detail and punchier and tighter bass, in addition to a better looking case and finish, the DO300 EX felt flimsy to me.
If only I could get to do the V.2 firmware update, that is no way to get It updated.
But despite a couple of Bugs that are supposed to be addressed with the so called V.2 firmware, I think the D400 PRO sounds great for the money.
Going back to Sound Colors, which one/ones you prefer?
2.2 (or .more), 4.2 (or .more). Not sure that I can tell the kHz level by ear. If it is CD or better quality, to my hearing, I do not think that it matters.
All except for this: Very Good Headphone Amp (already have many good ways for that & try not to be using headphones, anyways.)
I see this a lot on these devices which makes me ponder: if I am paid $36 an hour, how much time (time is money, enjoyment, family or many other things BUT YOU CANNOT GET IT BACK) worth? For me, the frequency rates that this happens before & after the warranties': My Chinese wife (I met her in Saipan 22 years ago) says that it's not worth the waste of time & aggregation that it causes to the quality of life. Buy a more reliable brand, even if it costs more money. Have less aggravation in life (even if it might not measure as well).
And be better off more times than not.
The one in your Avatar is one of my favorite AMP's ever (design and function when the circuits are not changed but just newer caps & more modern tighter tolerance electronics are installed in those circuits).
You would be amazed what visuals do when you don't have to hide it because it's annoying to see. On the other hand, some don't care (believe it or not). Even when I did not have a wonderful wife I did care somewhat about how things looked. In the last 20 years, how things look has become pretty important to me. Ugly is absolutely NOT OK, innocuous CAN be tolerated, with the proper adjustments & nice looking just makes my life much simpler in general.
So, spending a few more of my limited $'s on how something looks (as long as it meets the functional criteria) for me, has major benefits & is a big selling point.
Thanks again for your explanation. I had no idea that DAC's with this AKM chipset combination work as 7 bit Delta/Sigma, regardless if the input is PCM, no matter the resolution, from 44.1/16 Red Book to 192/24, that is the maximum I can play with my current source, a Sony UBP X-8OO M2 UHD BD/SACD player, but also do the same when playing DSD which is 1 bit Delta/Sigma..
I don't know, with my limited knowledge on this, that 1 bit Delta/Sigma DSD could be converted to 7 bit Delta/Sigma keeping its original sampe rate, that is 2.8 Mhz for SACD's DSD 64 (I have ripped all my SACD's and extracted the tracks from their ISO's with ISOSDSD, I play them, along some of my most listened CD's and High Res files from an SSD)..
But I wonder if one has the "Fixed Volume DSD bypass/unprocessed" (or something like this, I'm not at home to have a look to the D400 PRO set Up menu), that is the option I have selected, DSD doesn't get converted to 7 bit Delta/Sigma. IS this true?
I don't think so as the AK4499EX is a 7 bit Delta/Sigma D/A converter.
Another question, as you seem to know a lot about this AKM chipset combination: when I play DSD 64 and I have selected either a 5.6 Mhz Sound Color, os a 11.2 Mhz one, does this mean that DSD 64 gets upsampled to these Sample rates, that are DSD 64 x2 or DSD 64 x4? Which are the benefits, if any, of doing this when playing DSD? With PCM I know this improves sound quality in many ways, this is good old school oversampling.
.
Changing subject, I thought that when playing DSD vía I²S with the "Fixed Volumen, DSD Unprocessed", the DSD data stream bypassed the AK4191 IC, the one that does filtering, oversampling and Delta/Sigma modulation, but having a look at the IC combo, this doesn't seem to be the case.
As I postee earlier, I owned the DO300 EX (I had the then top of the like Sabre based DO300, before It, that was never my cup of tea, I found It cold and analitycal) and after liking the sound of the DO300 EX, I decided to get the more elaborate D400 PRO, and I do find It to sound better than the DO300EX, despite sharing the same AKM chipset. I wished I had the money to get the single AK4191 plus dual AK4499EX
Thanks again for your explanation. I had no idea that DAC's with this AKM chipset combination work as 7 bit Delta/Sigma, regardless if the input is PCM, no matter the resolution, from 44.1/16 Red Book to 192/24, that is the maximum I can play with my current source, a Sony UBP X-8OO M2 UHD BD/SACD player, but also do the same when playing DSD which is 1 bit Delta/Sigma..
I don't know, with my limited knowledge on this, that 1 bit Delta/Sigma DSD could be converted to 7 bit Delta/Sigma keeping its original sampe rate, that is 2.8 Mhz for SACD's DSD 64 (I have ripped all my SACD's and extracted the tracks from their ISO's with ISOSDSD, I play them, along some of my most listened CD's and High Res files from an SSD)..
But I wonder if one has the "Fixed Volume DSD bypass/unprocessed" (or something like this, I'm not at home to have a look to the D400 PRO set Up menu), that is the option I have selected, DSD doesn't get converted to 7 bit Delta/Sigma. IS this true?
I don't think so as the AK4499EX is a 7 bit Delta/Sigma D/A converter.
Another question, as you seem to know a lot about this AKM chipset combination: when I play DSD 64 and I have selected either a 5.6 Mhz Sound Color, os a 11.2 Mhz one, does this mean that DSD 64 gets upsampled to these Sample rates, that are DSD 64 x2 or DSD 64 x4? Which are the benefits, if any, of doing this when playing DSD? With PCM I know this improves sound quality in many ways, this is good old school oversampling.
.
Changing subject, I thought that when playing DSD vía I²S with the "Fixed Volumen, DSD Unprocessed", the DSD data stream bypassed the AK4191 IC, the one that does filtering, oversampling and Delta/Sigma modulation, but having a look at the IC combo, this doesn't seem to be the case.
As I postee earlier, I owned the DO300 EX (I had the then top of the like Sabre based DO300, before It, that was never my cup of tea, I found It cold and analitycal) and after liking the sound of the DO300 EX, I decided to get the more elaborate D400 PRO, and I do find It to sound better than the DO300EX, despite sharing the same AKM chipset. I wished I had the money to get the single AK4191 plus dual AK4499EX D400 EX.
Anyway, I find this AKM AK4191+AK4499EX combination as used on SMSL'S DO300 EX or the D400 PRO to sound extremely well for the money.
nanook
Senior Member
@Kiko1974
There's a thread discussing the AK4191/AK4499EX in some detail (page 3 starts to get into the innards):
www.audiosciencereview.com
One ASR member got some questions answered elsewhere:
audiophilestyle.com
It seems the AK4499EX is "just" a high quality 7 bit DAC that is meant to be operated with a SD input at 2 different frequencies.
All of the inputs to the AK4191 seem to be converted to a 5-7 bit SD stream.
The DWA takes place in the actual DAC, AK4499EX.
I'm not very much into the innards of DAC chips either. I do measurements on the DACs that I have using Cosmos ADCiso and APU.
I still need to build or order a passive LC lowpass filter, I figured when measuring the DO300EX. The hefty noise beyond 70 kHz (5.6 MHz operation) with no reasonable output filter in this unit screwed up the measurements I'm afraid).
PS: just saw that you participated in this ASR thread.
Edit: We should continue this discussion in the AK4499EX thread - here it's heavily off-topic.
There's a thread discussing the AK4191/AK4499EX in some detail (page 3 starts to get into the innards):
AKM new flagship AK4191 + AK4499EX
I just saw the SMSL has new flagship inplementing this new AKM combo. Below is the summary from goog, so can someone with expertise in this explain if this is just a gimmick (splitting into 2 chips like this)? And what is that signal from AK4191 going into AK4499EX? DSD, PCM or something else...
www.audiosciencereview.com
One ASR member got some questions answered elsewhere:
HQ Player
audiophilestyle.com
It seems the AK4499EX is "just" a high quality 7 bit DAC that is meant to be operated with a SD input at 2 different frequencies.
All of the inputs to the AK4191 seem to be converted to a 5-7 bit SD stream.
The DWA takes place in the actual DAC, AK4499EX.
I'm not very much into the innards of DAC chips either. I do measurements on the DACs that I have using Cosmos ADCiso and APU.
I still need to build or order a passive LC lowpass filter, I figured when measuring the DO300EX. The hefty noise beyond 70 kHz (5.6 MHz operation) with no reasonable output filter in this unit screwed up the measurements I'm afraid).
PS: just saw that you participated in this ASR thread.
Edit: We should continue this discussion in the AK4499EX thread - here it's heavily off-topic.
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Matt_Holland
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If you have documentation on how these tests were carried out and the results, would you mind sharing?
I have the chance to return the D400 PRO (despite liking its sound a lot) that I paid 690 Euros for It.
But It looks like this new RAW-DAC 1 from SMSL, based on the same AKM chipset may sound the same at a lower cost.
I wouldn't think about getting rid of the D400 PRO if It wasn't for the so called firmware update V2.0, that is imposible to do the update.
But It looks like this new RAW-DAC 1 from SMSL, based on the same AKM chipset may sound the same at a lower cost.
I wouldn't think about getting rid of the D400 PRO if It wasn't for the so called firmware update V2.0, that is imposible to do the update.
I have the same Tone board as well, and while I’m happy with the sound quality, I’ve had this consistent issue. Whenever I power on my active speakers *before* turning on the computer (which the KTB1 is connected to), I hear a loud and unsettling “pop” noise. Do you have the same issue?
To avoid the pop, I have to make sure all amps and speakers are turned off before powering on the KTB1.
