TeraDak DC-30 Linear Power Supply - Review

DarqueKnightDarqueKnight Posts: 6,569
edited February 26 in Going Digital
Introduction

Very good results were achieved by replacing the stock generic "wall wart" power supply of my music library's hard disk drive enclosure with a lower noise iFi Audio iPower power supply ($49). Although the iPower power supply facilitates better sound than the stock power supply, it is still a switch mode power supply like the stock power supply. Accordingly, the quality of DC power supplied by it is affected by AC noise components. Linear power supplies are more suitable for audio applications due to their significantly lower output noise and isolation from AC line noise. The TeraDak DC-30 ($150) offers high build quality and high performance.

Background

This review is the fourth addendum to my review of the Bryston BDP-3 digital player. Music files for the player are contained in a 6 TB hard disk drive, which is contained in a Rosewill Armer RX304-APU3-35B external hard drive enclosure. This review will be more meaningful if the BDP-3 review, and first three addendums, are read first.

The original BDP-3 review is here:

https://forum.polkaudio.com/discussion/comment/2471987#Comment_2471987

The first addendum, a review of the iFi Audio iPower power supply used with BDP-3's external hard drive enclosure is here:

https://forum.polkaudio.com/discussion/comment/2474000

The second addendum, a review of the iFi Audio Mercury3.0 USB 3.0 cable, used between the external hard drive enclosure and the BDP-3, is here:

https://forum.polkaudio.com/discussion/comment/2477644

The third addendum, a review of the Seagate 5 TB 2.5" hard disk drive, is here:

https://forum.polkaudio.com/discussion/185455/seagate-5-tb-internal-hard-drive-for-bryston-bdp-3-digital-player-review

My listening evaluation methodology and the musical selections used are discussed in detail in the original BDP-3 review, therefore they will not be rehashed here.

At the end of the Seagate 5 TB hard drive review, I noted that I heard no difference between music files played from either the internal Seagate drive, or the external Western Digital Black 6 TB drive in its upgraded enclosure. However, when the external enclosure's upgrade USB 3 cable and upgrade power supply were taken away, music from the internal Seagate drive sounded better. The addition of the TeraDak linear power supply caused the external drive's sound performance to leapfrog over that of the internal drive.

Physical Overview

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Figure 1. The DC-30 is encased in a high quality machined aluminum chassis. TeraDak recommends a break in period of one week. Clarity and detail improved after 24 hours. I did not hear further improvements due to additional playing time after that.

All those ventilation holes are not there for show. The DC-30 gets hot. Linear power supplies have lower efficiency than switch mode power supplies, therefore more of a LPS's energy is converted to heat. The top cover was 120 degrees Fahrenheit within a few minutes of being turned on. In comparison, the heat sinks of my Pass Labs X600.5 power amplifiers are in the range of 125 to 130 degrees Fahrenheit after an hour of playing at moderate levels (~85 dB-C). Temperature was measured with a Fluke model 561 infrared thermometer.

The DC-30 measures 4.25" wide by 6.5" long by 2.375" high and weighs 2.1 pounds.
Aluminum panel thicknesses are as follows:

Front panel: 0.12"
Rear panel: 0.08"
Side panels: 0.155"
Top and bottom panels: 0.1"

Panel thicknesses were measured with Mitutoyo model CD-6 CSX digital calipers.

2avyx2wa26a1.jpg
Figure 2. DC-30 rear panel. Output is 12 volts at 2 amperes, same as the Rosewill enclosure's stock power supply.

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Figure 3. The fuse compartment below the IEC power cord inlet has a spare fuse (the fuse closest to the rear).

tt4roaq2tp29.jpg
Figure 4. The interior of the DC-30 is dominated by the Audiophonics R-core transformer. The transformer might be a custom design as I did not find this model (R20-DS3853) on the Audiophonics website. The DC-30 is marketed as an upgrade power supply for the Musical Fidelity V90 DAC.

R-core transformers offer some of the sonic advantages of toroidal transformers at a much lower cost.

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Figure 5. A 1 meter DC power cable and 1.5 meter 18 gauge IEC power cord are included.

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Figure 6. I didn't look closely enough at the picture of the DC-30's DC cable on the TeraDak website to notice it was a little bit too skinny. Standard size in the U.S. is an external barrel diameter of 5.5 mm and an interior diameter of 2.1 mm. The power plug of the cable I received was substantially smaller, as shown in figure 7.

mbmzzviwuo5o.jpg
Figure 7. The DC-30's DC power plug (bottom) was too small (3.46 mm barrel diameter) for the Rosewill enclosure's DC power port. I ordered two different color Switchcraft plugs #762 (black) and #763 (red) from Mouser. I couldn't decide which color I liked best prior to ordering.

TeraDak confirmed via email that a 5.5 mm x 2.1 mm plug is available, but it, like the input voltage, needs to be specified at the time of ordering.

The Sound

In summary, the spatial improvements were spectacular.

A playlist was made of twenty songs, ten pulled from the internal Seagate drive and the same ten pulled from the external Western Digital drive. Music from the external drive, with the TeraDak LPS, had the following differences:

1. More weight and more of a sense of space around sound images.
2. Increased tactile sensation: More sound pressure against my chest and upper arms corresponding to bass beats.
3. On some songs, some sound images were raised 6 inches to 1 foot higher.
4. On some songs, depth was increased by the sound stage moving forward up to1 (or more) foot in the center and up to 2 feet (or more) at the sides.
5. Piano notes had more detail, sustain, and decay, and more airiness and "sparkle" in the high notes.
6. More detail in bass micro-rumble and micro-growl.
7. Lowered noise floor as evidenced by the music sounding louder, but not actually measuring louder.
8. More dynamics.
9. Sharper transients.

"So hot it burns Mice!"~DK
"Polk SDA-SRSs are hopelessly out of date both sonically and technologically... I see no value whatsoever in older SDA speakers."~Audio Asylum Member
"Knowledge, without understanding, is a path to failure."~DK
"Those who irrationally rail against something or someone that is no threat to them, actually desire (or desire to be like) the thing or person they are railing against."~DK
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Comments

  • DarqueKnightDarqueKnight Posts: 6,569
    edited February 26
    Measurements

    Time domain (sine wave) and frequency domain (Fast Fourier Transform) measurements were taken with a Tektronix TDS-2012 digital oscilloscope.

    The TeraDak LPS was plugged into a PS Audio PowerBase noise gate/isolation platform, which was plugged into a PS Audio P10 AC regenerator, which was plugged into a dedicated 20 amp AC circuit terminated with an in-wall PS Audio Soloist SE passive power conditioner.

    yw0fr4rgnanf.jpg
    Figure 8. Sine wave plot of passively filtered open circuit AC voltage from the wall. The waveform shows flattened peaks due to harmonic distortion and other power line noise.

    5t3a8njfowlx.jpg
    Figure 9. Sine wave plot of regenerated open circuit AC voltage measured at the output of the PS Audio PowerBase: A near perfect sine wave shape.

    6zpodqc1o8l9.jpg
    Figure 10. FFT plot of passively filtered open circuit AC voltage from the wall. The only signal of value is the large spike on the left, which represents the 60 Hz power signal. Everything else is harmonics, the power company's 470 Hz signaling tone, and noise.

    z9dfjurw73uc.jpg
    Figure 11. FFT plot of regenerated open circuit AC voltage measured at the output of the PS Audio PowerBase: Drastic reduction in harmonics and noise.

    9w4x2j6o7j06.jpg
    Figure 12. FFT plot of open circuit AC voltage measured at the output of the Rosewill enclosure's stock Flypower switch mode power supply. This power supply generates even order harmonics, which were not present in the original voltage signals from neither the wall nor the AC regenerator.

    hz0dfsr0v7u3.jpg
    Figure 13. FFT plot of open circuit AC voltage measured at the output of the iFi Audio iPower switch mode power supply. No even order harmonics were generated, but the odd order harmonics are significantly greater in amplitude in the voltage from both the wall and the AC regenerator.

    sas9pbpcv3e7.jpg
    Figure 14. FFT plot of open circuit AC voltage measured at the output of the TeraDak LPS. In stark contrast to the switch mode power supplies, no AC artifacts at all.

    Tweaks

    After preliminary listening evaluations were completed, attention was turned toward tweaking. The first thing to address was the DC-30's very bright LED.

    exgh09omq32j.jpg
    Figure 15. Something needed to be done about that "red sun" LED.

    m1mui1yaodds.jpg
    Figure 16. Even with the audio equipment cabinet door closed, the red sun still shined brightly.

    zo9hgactm38b.jpg
    Figure 17. A double layer of blue film reduced the red sun to a warm, mellow red glow.

    If you have had good results with audio grade fuses and audio grade power cords, and if you are interested in this, or another, linear power supply, an upgrade power cord and audio grade fuse is worth auditioning.

    mq8rw1rqyzex.jpg
    Figure 18. The stock 18 gauge power cord was replaced with a Signal Cable MagicPower 10 gauge power cord ($79) that was in my box of spare power cords.

    x9rbtrbsd488.jpg
    Figure 22. After some audio grade fuse trials, the stock 5 mm x 20 mm Miro R054 1A, 250V slow blow fuse ($0.25), was replaced with one of the HiFi Tuning SilverStar 1A fuses ($40) I had on hand.

    Off To Work

    I took the Teradak LPS to audition in my system at work. The internal Seagate 5 TB hard disk drive had already been placed in a Rosewill Armer RX304-APU3-35B external enclosure in order to take advantage of the Rosewill's drive spin down feature. The iPower power supply formerly used in my two channel system had been transferred to the work system. The improvements were immediately obvious and similar to what I heard at home. A second TeraDak LPS was ordered for the work system.

    "So hot it burns Mice!"~DK
    "Polk SDA-SRSs are hopelessly out of date both sonically and technologically... I see no value whatsoever in older SDA speakers."~Audio Asylum Member
    "Knowledge, without understanding, is a path to failure."~DK
    "Those who irrationally rail against something or someone that is no threat to them, actually desire (or desire to be like) the thing or person they are railing against."~DK
  • DarqueKnightDarqueKnight Posts: 6,569
    edited February 26
    Comparison To Network Attached Storage (NAS)

    A NAS is used by some audio enthusiasts to host their music libraries. Ethernet is a low noise transmission protocol due to the fact that Ethernet ports are galvanically isolated (transformer coupled). Therefore, there is no direct electrical connection between devices on an Ethernet network. Accordingly, most of the electrical noise in a device does not get transmitted to other devices over an Ethernet cable. A small amount of noise does get transferred over, but it is usually negligible in amplitude and usually inaudible.

    I transferred 7 DSD64 songs to the Synology DS918+ NAS in my home theater system. The seven songs' titles were edited to include the acronym "NAS" at the end. A share was set up on the BDP-3 digital player's NAS interface. A playlist was made of the NAS songs and their counterparts on the external drive attached to the BDP-3. Songs from the NAS sounded identical in every way to songs from the external drive with its enclosure's upgraded power supply and upgraded USB 3 cable.

    The first trials were done with songs streamed wirelessly via the following transmission chain:

    Synology NAS ==>Ethernet Cable==>Wireless AC Range Extender #2 ==>Wireless Air Interface==>Wireless AC Range Extender #1==>Ethernet Cable==>BDP-3

    With wireless streaming from the home theater NAS, I experienced occasional 1-2 second dropouts and stuttering. This was surprising, since wirelessly streaming 2K and 4K Blu-rays to any of my home's other televisions never experience any dropouts or stuttering. The home theater television has a wired connection to the NAS.

    I ran a 50 foot Cat5e cable from the home theater's NAS to the two channel system's wireless AC range extender. Streaming of music from the NAS over the wired connection was flawless.

    Wired transmission chain:

    Synology NAS ==>50' Ethernet Cable==>Wireless AC Range Extender #1==>Ethernet Cable==>BDP-3.

    Summary Of Results

    The summary of results is as follows:

    1. The internal 5 TB Seagate HDD sounded better than the 6 TB WD Black HDD in the stock Rosewill enclosure.
    2. The 6 TB WD Black HDD with the Rosewill enclosure's iFi Audio iPower switch mode power supply and iFi Audio Mercury3.0 USB 3 cable sounded the same as the internal 5 TB Seagate HDD.
    3. The 6 TB WD Black HDD with the Rosewill enclosure's TeraDak linear power supply and Mercury3.0 USB 3 cable sounded better than the internal 5 TB Seagate HDD.
    4. The Synology NAS sounded the same as the 6 TB WD Black HDD with the Rosewill enclosure's TeraDak linear power supply and Mercury3.0 USB 3 cable.
    5. The internal 5 TB Seagate HDD sounded better than the 5 TB Seagate HDD in the stock Rosewill enclosure.
    6. The external 5 TB Seagate HDD in the Rosewill enclosure with upgraded USB 3 cable and upgraded power supply sounded better than the internal 5 TB Seagate HDD.

    Further Study

    The sound quality result with the Synology DS918+ NAS was intriguing. I am considering moving my music library to a Synology DS718+ NAS with two WD Red Pro 6 TB drives in RAID1 configuration. This option would cost $200 more than the current external hard drive connected to the BDP-3. However, the BDP-3 and its external hard drive are currently used as a quasi-NAS for the various computers and music players in my home. A real NAS would be a more efficient solution.

    Associated Equipment - Home Two Channel Stereo System

    Bryston BDP-3 digital player
    PS Audio PowerBase isolation platforms for DAC, BDP-3, and U-Clock
    22 pound granite slabs to couple source components to isolation platforms
    Black Diamond Racing Isolation Mini Pits and Mk IV Cones
    dCS Puccini U-Clock word clock
    dCS Debussy DAC
    Rosewill Armer RX304-APU3-35B hard drive enclosure with 6 TB WD Black hard drive
    iFi Audio Mercury3.0 USB 3 cable
    Pass Labs XP-30 line level preamplifier
    Pass Labs X600.5 monoblock power amplifiers
    AudioQuest Sky XLR interconnects
    AudioQuest Everest speaker cables
    Revelation Audio Labs Prophecy CryoSilver digital coaxial cable - RCA connectors
    Revelation Audio Labs Prophecy CryoSilver digital coaxial cable - BNC connectors
    Revelation Audio Labs Prophecy CryoSilver USB 2.0 dual leg cable
    PS Audio PerfectWave AC-12 power cords
    PS Audio PerfectWave P-10 AC regenerator
    Polk Audio SDA SRS 1.2TL loudspeakers (heavily modified)
    Salamander Synergy Triple 30 audio credenza
    Logitech Harmony One remote
    Dell 7140 tablet computer for system control

    Associated Equipment - Work Two Channel Stereo System

    Bryston BDP-2 digital player
    Bryston BDA-3 digital to analog converter
    Bryston BP-26/MPS-2 preamplifier/power supply
    Bryston 4B3 power amplifier
    Rosewill Armer RX304-APU3-35B hard drive enclosure with 5 TB Seagate hard drive
    Polk Audio SDA CRS+ loudspeakers (heavily modified)
    Douglass Connection DCF92 speaker cable
    Revelation Audio Labs 1.25m USB 2.0 split configuration USB 2.0 cable
    PS Audio Premier SC 1.5m Power Cords for amplifiers and source components
    PS Audio PerfectWave AC-12 power cord 2m For P10
    PS Audio xStream Transcendent XLR interconnects 1m
    PS Audio xStream Transcendent XLR interconnect 1.5m
    PS Audio P10 AC Regenerator
    Revelation Audio Labs power umbilical for MPS-2/BP-26
    Logitech Harmony One remote
    Dell 7140 tablet computer for system control
    Post edited by DarqueKnight on
    "So hot it burns Mice!"~DK
    "Polk SDA-SRSs are hopelessly out of date both sonically and technologically... I see no value whatsoever in older SDA speakers."~Audio Asylum Member
    "Knowledge, without understanding, is a path to failure."~DK
    "Those who irrationally rail against something or someone that is no threat to them, actually desire (or desire to be like) the thing or person they are railing against."~DK
  • headrottheadrott Posts: 5,435
    Very good info Raife. Linear power supplies greatly improve the audio signal in my experience. I love the fact that you used a Hi-Fi Tuning Silver Star fuse in the application. Many people scoff at the fact one may use an audio grade fuse in any application, but I have experienced improvements in audio output using audio grade fuses.

    Thanks for the thread and information.
    Relayer-Big-O-Poster.jpg
    Taken from a recent Audioholics reply regarding "Club Polk" and Polk speakers:
    "I'm yet to hear a Polk speaker that merits more than a sentence and 60 seconds discussion." :\
    My response is: If you need 60 seconds to respond in one sentence, you probably should't be evaluating Polk speakers.....


    "Green leaves reveal the heart spoken Khatru"- Jon Anderson

    "Have A Little Faith! And Everything You'll Face, Will Jump From Out Right On Into Place! Yeah! Take A Little Time! And Everything You'll Find, Will Move From Gloom Right On Into Shine!"- Arthur Lee
  • mhardy6647mhardy6647 Posts: 22,979
    edited February 27
    Seems like a P/S like that would benefit from a little more space for air circulation to help dissipate heat.

    The old (CB era) 4A regulated linear P/S I've been using lately just barely gets warm (powering a low powered but inefficient Class AB junker chip amp), but it is much larger and well ventilated.

    0qk4yc9zhhvp.png

  • mhardy6647mhardy6647 Posts: 22,979
    edited February 27
  • DarqueKnightDarqueKnight Posts: 6,569
    mhardy6647 wrote: »
    Seems like a P/S like that would benefit from a little more space for air circulation to help dissipate heat.

    I sent TeraDak a picture of the P/S, describing the amount of space all around and the case temperature. They said there no issues with the placement.

    "So hot it burns Mice!"~DK
    "Polk SDA-SRSs are hopelessly out of date both sonically and technologically... I see no value whatsoever in older SDA speakers."~Audio Asylum Member
    "Knowledge, without understanding, is a path to failure."~DK
    "Those who irrationally rail against something or someone that is no threat to them, actually desire (or desire to be like) the thing or person they are railing against."~DK
  • mhardy6647mhardy6647 Posts: 22,979
    edited February 28
    I meant the enclosure of the P/S itself. Seems a bit tightly packed to me, and your description struck me as a little warm for a 2A supply.

    Heat really is (or, at least it can be) the enemy. :|
  • Moose68BashMoose68Bash Posts: 3,597
    @DarqueKnight,

    A great review with very useful information for those of us who do not approach your level of knowledge and sophistication about these matters.

    Thank you.

    I infer from your review that I would be unlikely to experience appreciable SQ improvement if I were to replace the switching-mode stock power supply on my Synology 713+ NAS with a linear power supply. My NAS is directly connected to my PS Audio DirectStream DAC with CAT 6 ethernet cable.

    Recently, I've been considering trying this upgrade, but it does not seem likely to be worth the investment in the linear power supply.

    However, I need to think about upgrading fuses in my components.
    Family Room, PS Audio PW Transport, DirectStream DAC w/Bridge II; AQ Sky XLRs, McIntosh MC 220 Tube Pre; AQ Sky XLRs, CAT 600.2 Dualmono Amp, Morrow SP7 Speaker Cables, SDA SRS 1.2tls (RD0198s, Dreadnought, Black Hole 5, Acousta-Stuf, Dynamat Extreme, JBWeld. Vr3 Mods: "The Abbot" Monastery-Level Xovers, Custom Internal Wiring, Binding Post Plates, & SDA ICs).

    Exercise Room, Wadia 171 iPod Dock, PS Audio PerfectWave MkII DAC w/Bridge II, AQ Sky XLRs, Perreaux PMF3150 Amp, Dreadnought, Supra Rondo 4x2.5 Speaker Cables, SDA 1Cs (Vr3 Mods Xovers).

    Synology 713+ NAS on Gigabit LAN serving PW MkII DAC & DirectStream DAC.
  • DarqueKnightDarqueKnight Posts: 6,569
    I infer from your review that I would be unlikely to experience appreciable SQ improvement if I were to replace the switching-mode stock power supply on my Synology 713+ NAS with a linear power supply. My NAS is directly connected to my PS Audio DirectStream DAC with CAT 6 ethernet cable.

    I typically don't discourage anyone from experimenting, even when the expected performance gains are small. However, in the case of a Synology NAS, using a power supply other than one made by Synology is considered a "third party modification" and voids the warranty.

    In my home theater system, my amplifiers, television, and source components all demonstrated better audio and video performance after being plugged into an AC regenerator. I have not (yet) done a test to see if, and how much, the movie server NAS benefits from being plugged into the AC regenerator. While it is on my list of things to investigate, I have not done it yet because I am not as tweaky regarding video as I am with stereo.

    I have ordered a Synology DS718+NAS for my home stereo system. I will evaluate it with and without regenerated AC and against the the external hard drive solution I currently use.
    mhardy6647 wrote: »
    I meant the enclosure of the P/S itself. Seems a bit tightly packed to me, and your description struck me as a little warm for a 2A supply.

    Heat really is (or, at least it can be) the enemy. :|

    I was actually alarmed by how hot the TeraDak PSU got, since it was too hot to handle and since it got almost as hot as my power amp's heat sinks. TeraDak said the heat is a consequence of the voltage regulator design they use. The perforated top cover and the all-aluminum case (which acts as a heat sink) are supposed to mitigate the potentially harmful effects of the heat.

    "So hot it burns Mice!"~DK
    "Polk SDA-SRSs are hopelessly out of date both sonically and technologically... I see no value whatsoever in older SDA speakers."~Audio Asylum Member
    "Knowledge, without understanding, is a path to failure."~DK
    "Those who irrationally rail against something or someone that is no threat to them, actually desire (or desire to be like) the thing or person they are railing against."~DK
  • mhardy6647mhardy6647 Posts: 22,979
    edited March 1
    I was, as you could tell, somewhat taken aback by the temperatures you reported for a 2A 12 volt power supply. I hope you are doing a "long term" test; it'll be interesting to see how long it holds up.

    I looked at their website to see if I could find a power consumption spec but I couldn't find this model P/S there. Is the power consumption specified on the DC-30 you have @DarqueKnight -- or did you happen to measure it?

    https://www.teradak.com/products/?id=25
    https://www.teradak.com/products/index.asp?id=25&Page=2
  • heiney9heiney9 Posts: 24,112
    Another great analysis.

    I've used a Welborne Labs linear power supply for my Squeezebox Touch for atleast the past 7-8 years. It makes a very significant improvement (to my ears) compared to the switching walwart that was supplied. Much of the what you describe is the same I experienced.

    Another great company that makes all sorts of power related gear is Keces Audio.

    http://keces-audio-usa.com/products

    I highly recommend going the route of a good linear power supply vs. a switching walwart in areas for critical musical listening, they improve the final output a great deal.

    H9
    "Appreciation of audio is a completely subjective human experience. Measurements can provide a measure of insight, but are no substitute for human judgment. Why are we looking to reduce a subjective experience to objective criteria anyway? The subtleties of music and audio reproduction are for those who appreciate it. Differentiation by numbers is for those who do not".--Nelson Pass

    Pass Aleph 30 | EE Avant Pre | EE Mini Max Plus DAC | MIT Shotgun S3 | MIT Z P/C's | updated SDA 1C| SQ Box Touch/Welbourne Labs P/S- Tubes add soul!
  • Mikey081057Mikey081057 Posts: 6,586
    I am using a TeraDak dual 12V / 6.5A Audiophile Hifi DC-200W Linear Power Supply
    power supply with my DAC and it is barely warm. Perhaps your application of the LPS is reaching or above it's upper limits?
    My New Year's resolution is 3840 × 2160

    HT:Polk LSiM 706 LSiM 705's VR3 LSiM 703's LSiM 702's| Marantz AV7704 | Sunfire TGA-7401 | Oppo UDP 203 | Sony PS4 Pro| Directv Genie HD DVR | Samsung 75" Q8 QLED | SVS PB13 Ultra | MIT EXP 2's (Fronts & Center)

    ManCave: Parasound Halo A21 | Parsound Halo A52+ | Marantz AV7002 AV PrePro | Usher Dancer Mini-x DMD's | Usher BE-616 Center | SVS Ultra Surrounds | SVS SB4000 Sub | SVS SB2000 Sub | Oppo UDP 203 | MIT Shotgun S3's | PSAudio Stellar GCD | Music Hall MMF 5.3se TT w/ Soundsmith Carmen | Mytek Brooklyn DAC+ | Lumin U1 Mini | HP Elite Slice PC | ROON'd for life | Samsung 50" SUHD TV | Sony PS4

    Patio | Polk Atrium 8's | Yamaha R-N303BL |

    Office |Cocktail Audio X14 | KEF LS50 | Peactree Nova 125SE |

    Bedroom | Focal 905's | Chromecast Audio |

    Garage | Polk Monitor 5B's

    Closet Yamaha M80 | 2 Polk MP3K subs| Yaqin MC100B with Shuguang Treasures KT 88's & CV181Z's | Tesla E83CC's | Marantz 2252B | Marantz 2385 | Bluesound Node |Polk SDA SRS 2.3 |
  • DarqueKnightDarqueKnight Posts: 6,569
    mhardy6647 wrote: »
    I was, as you could tell, somewhat taken aback by the temperatures you reported for a 2A 12 volt power supply. I hope you are doing a "long term" test; it'll be interesting to see how long it holds up.

    I am testing long term. I have ordered a second DC-30 for my system at work. Keeping the DC-30 in my home stereo system depends on whether the external HDD is replaced with the recently ordered Synology DS718+ NAS.
    mhardy6647 wrote: »
    I looked at their website to see if I could find a power consumption spec but I couldn't find this model P/S there. Is the power consumption specified on the DC-30 you have @DarqueKnight -- or did you happen to measure it?

    https://www.teradak.com/products/?id=25
    https://www.teradak.com/products/index.asp?id=25&Page=2

    There are a lot of "DC-30s" corresponding to the particular stock power supply they are designed to replace. My DC-30 is designed to replace the 12 v 2A wall wart that comes with Musical Fidelity's V90 DAC.

    This is the product page for my DC-30 variant:

    https://www.teradak.com/products/89.html

    The face plate on my unit says "DC-30", but the website pictures say "DC-30W". I don't know what the "W" designates. I'm guessing the "W" is for 230v models and the "non-W" models are 115V. I sent an email to TeraDak asking for clarification.
    I am using a TeraDak dual 12V / 6.5A Audiophile Hifi DC-200W Linear Power Supply power supply with my DAC and it is barely warm. Perhaps your application of the LPS is reaching or above it's upper limits?

    Maybe so.

    With the unit turned on, but not connected to anything, the top cover reaches a temperature of 96 degrees F.

    With the unit turned on and connected to the hard drive enclosure with the enclosure's fan running, but the hard drive idle, the the top cover reaches a temperature of 105 degrees F.

    With the unit turned on and connected to the hard drive enclosure with the enclosure's fan and hard drive running, the the top cover reaches a temperature of 120 degrees F.
    "So hot it burns Mice!"~DK
    "Polk SDA-SRSs are hopelessly out of date both sonically and technologically... I see no value whatsoever in older SDA speakers."~Audio Asylum Member
    "Knowledge, without understanding, is a path to failure."~DK
    "Those who irrationally rail against something or someone that is no threat to them, actually desire (or desire to be like) the thing or person they are railing against."~DK
  • Mikey081057Mikey081057 Posts: 6,586
    edited March 1
    The TeraDak LPS is a nice upgrade to any DAC with a wall wart in it lowers the noise floor and improves sound quality and sound stage... They are very well made and you can find one to fit your needs
    My New Year's resolution is 3840 × 2160

    HT:Polk LSiM 706 LSiM 705's VR3 LSiM 703's LSiM 702's| Marantz AV7704 | Sunfire TGA-7401 | Oppo UDP 203 | Sony PS4 Pro| Directv Genie HD DVR | Samsung 75" Q8 QLED | SVS PB13 Ultra | MIT EXP 2's (Fronts & Center)

    ManCave: Parasound Halo A21 | Parsound Halo A52+ | Marantz AV7002 AV PrePro | Usher Dancer Mini-x DMD's | Usher BE-616 Center | SVS Ultra Surrounds | SVS SB4000 Sub | SVS SB2000 Sub | Oppo UDP 203 | MIT Shotgun S3's | PSAudio Stellar GCD | Music Hall MMF 5.3se TT w/ Soundsmith Carmen | Mytek Brooklyn DAC+ | Lumin U1 Mini | HP Elite Slice PC | ROON'd for life | Samsung 50" SUHD TV | Sony PS4

    Patio | Polk Atrium 8's | Yamaha R-N303BL |

    Office |Cocktail Audio X14 | KEF LS50 | Peactree Nova 125SE |

    Bedroom | Focal 905's | Chromecast Audio |

    Garage | Polk Monitor 5B's

    Closet Yamaha M80 | 2 Polk MP3K subs| Yaqin MC100B with Shuguang Treasures KT 88's & CV181Z's | Tesla E83CC's | Marantz 2252B | Marantz 2385 | Bluesound Node |Polk SDA SRS 2.3 |
  • mhardy6647mhardy6647 Posts: 22,979
    In fairness, 120 degrees isn't hot by any stretch -- but it is pretty warm (perhaps disconcertingly so).

    Thanks for the clarification on the model -- I couldn't find a 2A 12VDC P/S on their site at all when I looked.

  • DarqueKnightDarqueKnight Posts: 6,569
    This thread was also posted on another forum where one of the members asked me if I had compared the noise measurements of the iPower and TeraDak power supplies plugged into the wall and plugged into the regenerated AC power chain. I had not, nor had it entered my mind to do so. I have been using extensive power conditioning for so long that the thought of plugging audio and video gear directly into the wall is not even in the far reaches of my imagination.

    The noise measurements for the Flypower SMPS, iPower SMPS, and TeraDak LPS were redone with cases for plugged into the wall and plugged into regenerated AC compared.

    The following time domain (sine wave) and FFT plots are with the iFi Audio iPower power supply and TeraDak LPS plugged into a regular household receptacle and into the PS Audio AC regenerator power chain.

    All measurements were taken within a few minutes of each other.

    The regenerated AC power chain consists of the following:

    Dedicated 20 Amp AC circuit==>PS Audio Soloist SE In-wall passive power conditioner==>PS Audio AC-12 noise filtering power cord==>PS Audio P10 AC regenerator==>PS Audio AC-12 noise filtering power cord==>PS Audio PowerBase isolation platform/noise gate.

    Electrical Environment Graphs

    1eg4y4l4hlnp.jpg
    Figure 20. Sine wave plot of open circuit AC voltage from regular household AC receptacle.

    nqe2jl0ke3oh.jpg
    Figure 21. FFT plot of signal and noise spectrum of open circuit AC voltage from regular household AC receptacle.

    Incoming power from the utility company has typical total harmonic distortion in the range of 1% to 1.5%, with the lower figure occurring in the early morning hours (2am - 6am) and higher figure in the daytime and early evening hours. The total harmonic distortion figure of power from the AC regenerator is 0.1%.

    1h4tgy0jf300.jpg
    Figure 22. Sine wave plot of regenerated open circuit AC voltage measured at the output of the PS Audio PowerBase.

    5z5xfuqyqug1.jpg
    Figure 23. FFT plot of regenerated open circuit AC voltage measured at the output of the PS Audio PowerBase.

    n539h3gysdqq.jpg
    Figure 24. Background noise of oscilloscope with no input. The noise floor is -27 dB (0.044 volts).

    Rosewill Enclosure Stock Flypower SMPS Graphs.

    0ea1ojnismqe.jpg
    Figure 25. Time domain plot of open circuit AC voltage measured at the output of the stock Flypower SMPS plugged into the wall.

    crr32rah366q.jpg
    Figure 26. Time domain plot of open circuit AC voltage measured at the output of the stock Flypower SMPS plugged into the PS Audio PowerBase.

    thte67dhuk7w.jpg
    Figure 27. FFT plot of open circuit AC voltage measured at the output of the stock Flypower SMPS when plugged into the wall.

    smy88mn7u984.jpg
    Figure 28. FFT plot of open circuit AC voltage measured at the output of the stock Flypower SMPS when plugged into the PS Audio PowerBase.

    iFi Audio iPower SMPS Graphs

    7o23p19hwo3w.jpg
    Figure 29. Time domain plot of open circuit AC voltage measured at the output of the iPower SMPS plugged into the wall.

    vlu09jyl72qk.jpg
    Figure 30. Time domain plot of open circuit AC voltage measured at the output of the iPower SMPS plugged into the PS Audio PowerBase.

    cdc7z490dcs8.jpg
    Figure 31. FFT plot of open circuit AC voltage measured at the output of the iPower SMPS when plugged into the wall.

    bg6zvdrm3thm.jpg
    Figure 32. FFT plot of open circuit AC voltage measured at the output of the iPower SMPS when plugged into the PS Audio PowerBase.

    TeraDak LPS Graphs

    These measurements were taken with the TeraDak's stock power cord and stock power line fuse.

    bzbwfm5y7ohn.jpg
    Figure 33. FFT plot of open circuit AC voltage measured at the output of the TeraDak LPS when plugged into the wall.

    rituah227kqm.jpg
    Figure 34. FFT plot of open circuit AC voltage measured at the output of the TeraDak LPS when plugged into the PS Audio PowerBase.

    The following measurements were taken after installing an upgrade power cord and upgrade power line fuse. The stock power cord was replaced with a Signal Cable MagicPower cord. The stock power line fuse was replaced with a HiFi Tuning SilverStar fuse.

    zwbnjllzrpa4.jpg
    Figure 35. After power cord and power line fuse upgrades: FFT plot of open circuit AC voltage measured at the output of the TeraDak LPS when plugged into the wall.

    cu9afwtyxyx0.jpg
    Figure 36. After power cord and power line fuse upgrades: FFT plot of open circuit AC voltage measured at the output of the TeraDak LPS when plugged into the PS Audio PowerBase.
    "So hot it burns Mice!"~DK
    "Polk SDA-SRSs are hopelessly out of date both sonically and technologically... I see no value whatsoever in older SDA speakers."~Audio Asylum Member
    "Knowledge, without understanding, is a path to failure."~DK
    "Those who irrationally rail against something or someone that is no threat to them, actually desire (or desire to be like) the thing or person they are railing against."~DK
  • ClipdatClipdat Posts: 7,137
    Thanks for going through the trouble of getting all these readings and measurements! Very interesting stuff.

    @K_M get your read on!
    "Electronic music is human sound adapting to indulge technology, and for some, it feels like the signature sound of energy. New and abstract sounds over hypnotic rhythms can conjure vast soundscapes for escape, pleasure, and transcendence."
  • K_MK_M Posts: 1,390
    Clipdat wrote: »
    Thanks for going through the trouble of getting all these readings and measurements! Very interesting stuff.

    @K_M get your read on!

    Just glanced, no time today to read much of anything, but looks interesting.
    Lsi15, Lsi9, LsiC,Rta11t,M5jr+,M4,SDA 3.1TL, SDA SRS 2.3TL, Rti6....Still listing stuff, a work in progress.
    B+W-Sold
    Epos-Now gone
    Infinity-Sold
    Advent-Now gone
    Yamaha A-S801
    Yamaha RX-V377
    Yamaha RX-A860
    Yamaha RX-A3060
    Harman Kardon Hk-350i
    Harman Kardon Hk-........
    Harman Kardon PM-665
    Harman Kardon HK-775
    Pioneer.......Stereo Receiver

  • delkaldelkal Posts: 568
    edited March 2

    The face plate on my unit says "DC-30", but the website pictures say "DC-30W". I don't know what the "W" designates. I'm guessing the "W" is for 230v models and the "non-W" models are 115V. I sent an email to TeraDak asking for clarification.

    The W is for watts. These use a 30 watt transformer on the input side. It shouldn't matter if the input is 120 or 230. The transformer puts out 30 watts at maximum rating.

    You Can see this in pic 4 of your op. The transformer has 2 lines out each supplying 15 watts each (15 volts x 1 amp). So combined its 30 watts.

  • mhardy6647mhardy6647 Posts: 22,979
    edited March 2
    Doesn't explain why some models have a "W" suffix & some don't.
    Just observin'.


    udmxlan4ovt7.png
  • Mikey081057Mikey081057 Posts: 6,586
    Maybe the W stands for units that will work in the bath tub?

    (do NOT try this!!!)
    My New Year's resolution is 3840 × 2160

    HT:Polk LSiM 706 LSiM 705's VR3 LSiM 703's LSiM 702's| Marantz AV7704 | Sunfire TGA-7401 | Oppo UDP 203 | Sony PS4 Pro| Directv Genie HD DVR | Samsung 75" Q8 QLED | SVS PB13 Ultra | MIT EXP 2's (Fronts & Center)

    ManCave: Parasound Halo A21 | Parsound Halo A52+ | Marantz AV7002 AV PrePro | Usher Dancer Mini-x DMD's | Usher BE-616 Center | SVS Ultra Surrounds | SVS SB4000 Sub | SVS SB2000 Sub | Oppo UDP 203 | MIT Shotgun S3's | PSAudio Stellar GCD | Music Hall MMF 5.3se TT w/ Soundsmith Carmen | Mytek Brooklyn DAC+ | Lumin U1 Mini | HP Elite Slice PC | ROON'd for life | Samsung 50" SUHD TV | Sony PS4

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    Office |Cocktail Audio X14 | KEF LS50 | Peactree Nova 125SE |

    Bedroom | Focal 905's | Chromecast Audio |

    Garage | Polk Monitor 5B's

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  • mhardy6647mhardy6647 Posts: 22,979
    Maybe the W stands for units that will work in the bath tub?

    (do NOT try this!!!)

    oh, it'll work in the bath tub...

    I was wondering if "W" might mean "world" (as in "rest of the world" - ROW - ex-US)?
    Yamaha, I think (?) used to label their ROW products, somewhat paradoxically, "U" (for Universal). Or maybe the "U" meant "United States" -- I just dunno. :p

    grcqid72ewik.png
  • mhardy6647mhardy6647 Posts: 22,979
    Check that. Looks like the "U" means U-nited States. :p

    cn1si01cn59y.png
  • DarqueKnightDarqueKnight Posts: 6,569
    In addition to the missing "W". The word "ON" is spelled backwards. Now I'm wondering if this is a case of a batch of face plates with errors in engraving. I'll see if
    TeraDak will send a replacement.

    m3i839p3gay2.jpg



    "So hot it burns Mice!"~DK
    "Polk SDA-SRSs are hopelessly out of date both sonically and technologically... I see no value whatsoever in older SDA speakers."~Audio Asylum Member
    "Knowledge, without understanding, is a path to failure."~DK
    "Those who irrationally rail against something or someone that is no threat to them, actually desire (or desire to be like) the thing or person they are railing against."~DK
  • mhardy6647mhardy6647 Posts: 22,979
    Oooh, I missed that.
    Dyslexics against switch-mode power supplies: Just say "NO".

    B)

    (with sincere apologies to any reading this thread who might indeed be dyslexic!)
  • delkaldelkal Posts: 568
    In addition to the missing "W". The word "ON" is spelled backwards. Now I'm wondering if this is a case of a batch of face plates with errors in engraving. I'll see if
    TeraDak will send a replacement.

    m3i839p3gay2.jpg

    It means No......its not off.
  • DSkipDSkip Posts: 16,115
    delkal wrote: »
    In addition to the missing "W". The word "ON" is spelled backwards. Now I'm wondering if this is a case of a batch of face plates with errors in engraving. I'll see if
    TeraDak will send a replacement.

    m3i839p3gay2.jpg

    It means No......its not off.

    I don't know man, that N sure looks upside down to me...
  • ClipdatClipdat Posts: 7,137
    In addition to the missing "W". The word "ON" is spelled backwards. Now I'm wondering if this is a case of a batch of face plates with errors in engraving. I'll see if TeraDak will send a replacement.

    Keep it, it adds character.
    "Electronic music is human sound adapting to indulge technology, and for some, it feels like the signature sound of energy. New and abstract sounds over hypnotic rhythms can conjure vast soundscapes for escape, pleasure, and transcendence."
  • DarqueKnightDarqueKnight Posts: 6,569
    Clipdat wrote: »
    In addition to the missing "W". The word "ON" is spelled backwards. Now I'm wondering if this is a case of a batch of face plates with errors in engraving. I'll see if TeraDak will send a replacement.

    Keep it, it adds character.

    I will keep the erroneous faceplate as I am sure TeraDak won't want it back, but I won't keep it on the power supply.
    "So hot it burns Mice!"~DK
    "Polk SDA-SRSs are hopelessly out of date both sonically and technologically... I see no value whatsoever in older SDA speakers."~Audio Asylum Member
    "Knowledge, without understanding, is a path to failure."~DK
    "Those who irrationally rail against something or someone that is no threat to them, actually desire (or desire to be like) the thing or person they are railing against."~DK
  • mhardy6647mhardy6647 Posts: 22,979
    DSkip wrote: »
    delkal wrote: »
    In addition to the missing "W". The word "ON" is spelled backwards. Now I'm wondering if this is a case of a batch of face plates with errors in engraving. I'll see if
    TeraDak will send a replacement.

    m3i839p3gay2.jpg

    It means No......its not off.

    I don't know man, that N sure looks upside down to me...
    Clipdat wrote: »
    In addition to the missing "W". The word "ON" is spelled backwards. Now I'm wondering if this is a case of a batch of face plates with errors in engraving. I'll see if TeraDak will send a replacement.

    Keep it, it adds character.


    3wp0csgny5no.png
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