The last post was about the updated LPSU board. A prototype unit of entry-level streamer was also built and briefly tested. 2 USB hub/regen cards were purchased to evaluate the SQ improvement with USB card. Windows 10 version 21H2 was launched. This post provides quick updates for each subject.
LPSU Tweaks
The updated LPSU board is gold plated, 3 oz. copper on both sides, and 2.1mm thick for better stiffness to support the weight of smoothing capacitors. It uses Texas Instruments’ LM1084 and LM1085 voltage regulators for first and second stage voltage regulations, providing maximum 5A per rail (only 5V standby is 3A rail). The 2 prototypes built earlier used TI’s LM1084 for first stage voltage regulation followed by Linear Technology’s LT1764A voltage regulators for second stage, providing 3A per rail. After serious listening and with the help from close friends who came and listened (thank you so much for your time and help), some tweaks were required to get the best sound quality. In other words, the voicing needs some improvement.
Luckily, the new LPSU board design has a daughter board for powering 5V devices such as SSD and USB card. This small board is only for second stage voltage regulation. Originally it uses LM1085 ad LM1086, but for powering USB power filter or USB card, it sounds a lot better when LT1764A is used. Hence, a new daughter board was designed and tested.
The use of 5A per rail improves dynamics and micro details compared to 3A per rail. With LT1764A used to power USB power filter or USB card, the streamer finally gets the voicing right.
The Arrival of JCAT USB XE
JCAT USB XE is considered the gold standard for USB hub / regen cards. Currently the card is still breaking in. It will be evaluated against Core Audio P24 OCXO purchased earlier. USB2 Redriver card is no longer being pursued. With the latest LPSU board, it sounds better without USB2 Redriver.
Both JCAT USB XE and Core Audio P24 OCXO were installed into the same FC10 case. The motherboard supports 1 PCIe x1 only, hence only 1 card can be used at a time. A PCIe riser was used (not shown in the above picture).
Windows 10 IoT Enterprise LTSC, version 21H2
Windows 10 version 21H2 was launch recently in Nov 2021. Windows 10 IoT Enterprise LTSC, version 21H2, provides significant SQ improvement compared to the previous versions of Windows 10 Enterprise LTSC and also the regular Windows 10. This will be the operating system used in the final product. The music streamer will ship with OEM licenses for Windows 10 IoT Enterprise LTSC and JPLAY FEMTO.
If you already have JPLAY FEMTO license, there is no need to purchase the license again. Please ask JPLAY support to transfer the license to a new motherboard.
Launch Date
The music streamer based on Streacom FC10 case is ready for in-house demo. Even without USB card, it is already at high performance level. For those with high-end and highly resolving hi-fi systems, it is recommended to use USB card since it elevates the performance to different level. JCAT FEMTO XE will be offered at special price if this music streamer is purchased directly from me. In-house demonstration is available in Klang Valley area. Please contact me if you would like to have a demonstration.
Entry-Level Streamer
The first unit of entry-level streamer was build using Fractal Design Note 202 computer case. All parts can fit it. However, the heatsink used was too small and unable to deal with voltage regulators heat management. It runs pretty hot and becomes unstable if the cover is in place. Performance wise, it sounds better than Innous Zenith Mk2 updated to the latest Innuos Sense 2.08, even when using ASRock motherboard’s USB2 port. The heat management needs some effort. Work on this is put on hold temporarily so that can focus 100% on preparation for product launch in December 2021.
Mohd Firdaus was kind enough to loan his JCAT FEMTO USB. He tested the prototype briefly but due to heat management issues, the recommendation was to stop evaluating the prototype. A better heatsink or maybe fan sink (due to space limitations) is required.
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