Melco recently announced the Melco EX series platform – this finally solves the problems caused by trying to Browse and Search music collections which have incomplete or inconstant metadata and permits browsing by any tag in any order, rather than the conventional (and very restrictive) ‘browse by Artist, Album, Song’.
We have created other documents highlighting the benefits of this advanced and unique technology (including the blog post here), but the purpose of this short post is to clarify the EX situation for existing Melco owners.
Melco EX upgrade on existing N1 Mk1 & Mk2
The current Melco N1 platform must be upgraded to the EX platform in order to accept the EX firmware. This is not a hardware change and can be applied to both Mk1 and Mk2 N1 machines. It is all software, but because the HDDs will need a total rebuild, the update can only be carried out by Melco or approved service points.
We will issue full details shortly, but the plan is to be able to offer upgrades from March 2020 - possibly sooner, dependant on the availability of some software tools.
All Melco dealers and distributors will have full details of how the service will be offered in each market in December, at the time of the EX hardware launch, so please speak to your dealer at that time.
Melco N1 EX machines released in December will be a higher price than current Mk2 machines, because of all the extra software licenses etc. So the EX upgrade will also carry a charge - this will be nominal for machines purchased after the EX announcement at Munich this year (May 2019) and for older Mk2 will be comparable to the price difference between Mk2 and EX.
Mk1 machines can also be upgraded - the costs will be confirmed in December and all Melco dealers will be aware of these.
The new Melco EX Platform includes both Melco Intelligent Music Library (MIML) and VTuner for Internet Radio when using USB-DAC and Melco Music HD app. The Melco Music HD app has recently been updated to include the VTuner capability when used with EX platform machines and this is visible to all users - but any Melco not running firmware V4.xx cannot use VTuner.
Melco N1 Mk1 and Mk2 without EX upgrade
N1 Mk1 and Mk2 that are not updated to EX platform V4.xx will continue to receive support updates to FW V3.xx.
For example, there will be a firmware release V3.92 which will include an Installer for MinimServer2 Starter Edition and SongKong Lite. Although these two installations do not match the functionality of EX, both can be upgraded by payment of license fees to the full versions. (You can purchase the MinimServer upgrade here. The SongKong full license can be purchased from here).
V3.92 will therefore allow for SongKong Lite and MinimServer Lite to be installed, but EX upgrade is necessary to give full EX functionality including front panel OLED control and Internet Radio.
We hope this helps clarify how to benefit from the EX platform – please do contact your dealer with further questions and as noted above, they can help with upgrades when the time comes.
The magic of DSD
There are many urban myths surrounding Direct Stream Digital (DSD), so I thought it might be interesting to look at DSD in detail and dispel some untruths. It may be simplified a little, but the following should give an insight into this remarkable format, in the context of Melco, of course, and is also applicable to USB-connected DACs as well as Ethernet streamers.
What is DSD?
Remember bitstream audio? It was used to indicate an elegant digital path in the mastering of LPs before CD was launched. It was a single-bit digital ‘stream’ and was considered a really useful digital format because decoding (D/A conversion) did not depend on high-precision resistive ladders etc. as used in DACs for PCM – at the time, 16-bit DACs were costly and had compromised performance.
PCM requires that the DAC has the ability to differentiate levels approximately 1/65,000 of peak level for 16 bits; more precision required for more bits. This requires an extremely precise ladder DAC or similar technology, whereas DSD is pulse density or delta-sigma modulation of a single bitstream; the decoding requires no special amplitude resolution and is, therefore, easier to implement.
Move the clock forward a few years and SACD uses the same digital stream with good results, making bitstream effectively a consumer format. With the advent of CD – a 16-bit PCM format – DACs have moved on in leaps and bounds since the ‘80s, but still there is the requirement to have extremely precise DAC implementation for 16, 24 or even 32-bit, or to use extreme oversampling/ clever data techniques to get around the basic problems of a PCM ladder DAC.
Bitstream never went away, though, and today it is known as DSD and offers many potential advantages over PCM.
There never was a specific physical carrier (silver disc) for DSD, so the download and digital files environment was necessary to popularise DSD. SACD is the same format but is copy protected, so the files do not move off of the silver disc carrier.
DSD exists in several forms:
There is the concept of single DSD or DSD 64 (being 64 times the sample rate of CD) and this is the original SACD standard. By doubling and quadrupling the data rate we get double DSD, DSD 128 and Quad DSD, DSD 256.
If the data was being created in the studio to master a CD, then the DSD would be 64, 128 etc. times the CD data rate. But if the data is being taken from analogue sources (microphone mixers, tape machines etc.) and is not for CD production, then the convention of 48 kHz sampling equivalent applies.
On the front of a Melco, when playing single DSD, a data rate of 2.8 MHz is shown for CD-related files and 3.1 MHz for 48 kHz related files.
How to justify record company claims ‘from the Master Tape/s’
The sample rate is a really useful clue as to the origins of the expensive download that you might have purchased and shows whether the claim, ‘Direct from the master tapes’ really applies or whether this has been lifted from CD-production data. Direct from an analogue tape will give DSD of 3.1, 6.1, 12.3 MHz etc. But, if the material was lifted from CD production data, the giveaway is the data rate of 2.8 MHz, 5.6 MHz etc.
To move DSD from one device to another, it is usually necessary to put the data into packets. This is also the case for USB and Ethernet. The packets contain the DSD data and have additional markers at the start and end of each packet to identify their place in the data queue. These markers take up around 30 per cent of the available bandwidth.
Some recent DACs and streamers can accept data without these markers. Melco supports this and tests the comms automatically. If markerless is possible with the specific DAC then there is a sound quality improvement due to the data rate dropping. There is no requirement for the user to intervene – markerless happens whenever possible; another clever Melco innovation!
DSD is really convenient but is not possible to easily edit, change levels, fade in and out of tracks etc. This requires PCM.
DXD is a 32-bit, 384 kHz (CD production) or 32/352 kHz PCM format. This is used before the finalised DSD.
Equivalent resolution DSD vs. PCM
The question always asked surrounds DSD vs. PCM resolution. They are totally different digitisation regimes and comparison is not easy, but it helps to think of SACD/single DSD/DSD 64 being something of the order of 20-bit resolution; sample rate equivalence depends on the DAC technique but it’s safe to say 96 kHz.
DSD 128 can be considered equivalent to a 24-bit PCM format.
There are several DACs that take full advantage of the DSD format. There are a lot more DACs that are based on PCM and, therefore, have to convert the DSD into PCM. Some do it well, some do not, and this is possibly the reason that opinion is divided on the merits of DSD. Conversion from DSD to PCM in the DAC is not so easy, the maths is immense.
With Melco connected to a USB DAC, you can choose! Many DSD-capable DACs are actually PCM DACs with inbuilt conversion. The Melco, however, can very precisely convert DSD into 32-bit PCM. Presenting this PCM data to a DAC designed originally for PCM is probably the best way to use the DAC with DSD.
DSD-over-Ethernet sometimes requires DoP (DSD over Packet) depending on the streamer; there are several one-time options for the Melco to communicate in the most stable way with the streamer.
Buying DSDs or DXD
As mentioned, there is no physical carrier for DSD (other than SACD which is copy-protected). But many vendors offer DSD and (in some cases) DXD downloads. If you purchase the highest resolution files you often can access the lesser files as well, making interesting sound quality comparisons.
Most telling is DXD versus Quad DSD: one uses a PCM DAC and the other a DSD DAC, so it allows a lot of insight into the performance of your hardware.
There are many vendors of DSD, but we do enjoy relationships with HighResAudio.com and Native DSD.com, plus both have samplers available for Melco owners. Particularly fine recordings are:
We hope this helps introduce you to the world of DSD – enjoy!