The Sound Of Hard Drive Enclosures

DarqueKnight
DarqueKnight Posts: 6,765
edited March 2017 in Going Digital
Introduction

For the time being, my entire music collection of CDs, SACDs, hi-rez downloads, and vinyl records resides on a 2 TB 3.5" Western Digital Black hard drive. CDs were ripped to 44.1 kHz FLAC files. SACDs were ripped to DSD64 dsf files. Vinyl records were rippled to DSD64 dsf files.

Running a hard drive at lower temperatures extends its life. I looked at a couple of fanned hard drive enclosures to replace a fanless and non-ventilated Vantech NexStar3 NST-360SU-BK enclosure. The The BDP-2 digital player does not "spin down" or "sleep" drives after a certain period of inactivity. Therefore any hard drives connected to the BDP-2 will spin 24/7 unless turned off by their power switches. I leave the BDP-2 on 24/7 and I leave its hard drive on 24/7.

Prior to ripping the portion of my vinyl collection that did not have digital versions, my music files resided on a 1 TB Samsung EVO 850 solid state drive installed in my Bryston BDP-2 digital player. Costs of 2 TB solid state drives are in the $500-$700 range at this time and I would prefer to wait until costs come down....way down.

The Unexpected Benefit

3-HDD%20Enc-CRP-s_zpsjcyxbjm6.jpg
Figure 1. Hard drive enclosures left to right: Sabrent EC-UEIS7 (fanned) $26, Rosewill RX304-APU3-35B (fanned) Armer $36, Vantec NexStar3 NST-360SU-BK (fanless) $30 The Sabrent's blue LEDs were so bright that they had to be covered with a piece of black electrical tape, leaving just a little bit of blue showing.

There was no perceivable difference in the sound of the same digital file played from the internal Samsung SSD or the Vantech enclosure connected via either eSATA cable or USB cable.

Surprisingly, the same file played from the Sabrent HDD enclosure's USB or eSATA connection sounded better than the internal Samsung SSD, with the eSATA connection sounding the best. The Rosewill HDD enclosure sounded worst among the Samsung SSD, Vantec enclosure, and Sabrent enclosure.

The Rosewill enclosure features a display for HDD temperature and fan speed, and displays are notorious for their electrical noise. Hard drive controllers and solid state drive controllers can also contribute to audible electrical noise. I was very disappointed that the Rosewill didn't win. It was the quietest, coolest running, best built, and coolest looking enclosure.

Digital files played from the Sabrent enclosure had more image weight, more three-dimensionality, more overall clarity and detail, and more micro details in the bass. Conversely, digital files played from the Rosewill enclosure were slightly veiled with blurred bass transients.

Only with the Sabrent enclosure could I hear a difference in music clarity and detail between a generic computer grade USB cable, a Pangea USB-PC cable ($35), and a Revelation Audio Labs Prophecy Cryo-Silver USB cable (split power and signal legs) ($549). However, the eSATA connection with a generic computer grade eSATA cable sounded better than any of the USB cable options.

Rosewill%20340%20Armer%20Enclosure%20Display-s_zpsl02ru3tk.jpg
Figure 2. Rosewill enclosure's temperature and fan speed display. My eyes loved the display, my ears hated the sound.

The Rosewill enclosure had a whisper quiet 80mm x 80mm fan that could not be heard from 3 feet away. Furthermore, the Rosewill enclosure and cradle damped the hard drive's vibrations. In contrast, the Sabrent's fan could be heard from 6 feet away and the enclosure produced a low hum when placed on the audio cabinet top.

Applying strips of Dynamat Xtreme to the inside of the Sabrent enclosure's top and bottom panels, the perimeter of the fan housing and the side panel opposite the fan side reduced the audible fan noise distance to 2.5 feet. The hum caused by placing the Sabrent enclosure on the cabinet was also significantly reduced by the Dynamat. The hum was eliminated completely by placing the enclosure on a 5" x 5" x 1" sorbothane pad.

Cooling Performance

SabrentRoswill%20Fan%20Side-Crp-s_zpslpitikj3.jpg
Figure 3. The Sabrent and Roswill enclosures both use an 80mm x 80mm fan, but the circular opening of the Sabrent enclosure does not extend all the way to the ends of the fan blades. It is 2-3/4" in diameter compared to 3-1/8" in diameter for the the Rosewill.

Fluke-561-IR-Thermo-CRP-s_zps7hmnehop.jpg
Figure 4. Enclosure temperature measurements were taken with a Fluke model 561 infrared thermometer.

The following measurements were taken after 1 hour of continuous music play:

Vantec enclosure:
Case top: 91 degrees F.
Case right side: 101 degrees F.
Case opposite side: 99 degrees F.

Sabrent enclosure:
Case top: 86 degrees F.
Case fan side: 91 degrees F.
Case opposite side: 92 degrees F.

Rosewill enclosure:
Case top: 87.1 degrees F.
Case fan side: 87.1 degrees F.
Case opposite side: 87.1 degrees F.

Digital display reading: 87.2 degrees F.

The WD Black hard drive in my home office computer runs at an average 118 degrees F (measured by Speedfan temperature monitoring software).
Proud and loyal citizen of the Digital Domain and Solid State Country!
Post edited by [Deleted User] on
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Comments

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  • DarqueKnight
    DarqueKnight Posts: 6,765
    Instead of worrying about heat, maybe buy an additional, inexpensive large external hard drive and back up your files onto it. $80-$100 at Amazon will buy a huge amount of storage.

    Thank you for your advice.

    However, this thread is about digital music servers and the hard drives attached to them...and the effects that the electrical noise produced by hard drive enclosures can have on the sound quality of digitally encoded music.

    Proud and loyal citizen of the Digital Domain and Solid State Country!
  • erniejade
    erniejade Posts: 6,321
    Why not a nas in a different room and transfer the music over Ethernet?
    Klipsch The Nines, Audioquest Thunderbird Interconnect, Innuos Zen MK3 W4S recovery, Revolution Audio Labs USB & Ethernet, Border Patrol SE-I, Audioquest Niagara 5000 & Thunder, Cullen Crossover II PC's.
  • Thorton
    Thorton Posts: 1,324
    erniejade wrote: »
    Why not a nas in a different room and transfer the music over Ethernet?

    I was wondering the same thing.
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  • DarqueKnight
    DarqueKnight Posts: 6,765
    No need for a NAS now. A good, low noise, vibration damped enclosure suffices for feeding digital music files to the BDP-2 digital player.
    Proud and loyal citizen of the Digital Domain and Solid State Country!
  • erniejade
    erniejade Posts: 6,321
    Are you going to try a different power supply on the enclosure next?
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  • erniejade
    erniejade Posts: 6,321
    Also was the same power supply used on all of them? Maybe the Sabrent had a better one and could attribute to the better sound?

    Klipsch The Nines, Audioquest Thunderbird Interconnect, Innuos Zen MK3 W4S recovery, Revolution Audio Labs USB & Ethernet, Border Patrol SE-I, Audioquest Niagara 5000 & Thunder, Cullen Crossover II PC's.
  • DarqueKnight
    DarqueKnight Posts: 6,765
    All three enclosures used the power supply that was packaged with it. I agree that the power supply of each enclosure might have affected the sound. I plan to do some noise studies on each enclosure when I have the time.
    Proud and loyal citizen of the Digital Domain and Solid State Country!
  • stevep
    stevep Posts: 335
    In the digital domain any changes in the data would be detected as read errors so what do you propose is the cause of the differences you heard?
  • erniejade
    erniejade Posts: 6,321
    My guess is power supply and even though it is an enclosure, there is still electronics inside that can produce noise. I would like to know if an Ifi or jitterbug filter would make a difference for him. @DarqueKnight if you are interested in trying a jitterbug, I have an extra one I can send to you to try out and see if that makes a difference or helps filter out some of the noise for you or makes it less of a difference between brands of enclosures.

    If your interested in trying one out, shoot me a PM and I can ship it to you. I have a spare I am not using.


    My rig is not as nice as @DarqueKnight 's but, on a cheap external drive, I have a jitterbug and I heard a difference. I have an external drive and a NAS both. I have been experimenting between the having it pull directly from the usb drive and then from the NAS upstairs. At first the NAS was walking all over the usb drive until I put in the jitterbug and that brought it much closer. The Nas is still the champ for now on my rig.
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  • DarqueKnight
    DarqueKnight Posts: 6,765
    erniejade wrote: »
    @DarqueKnight if you are interested in trying a jitterbug, I have an extra one I can send to you to try out and see if that makes a difference or helps filter out some of the noise for you or makes it less of a difference between brands of enclosures.

    Thanks EJ. I would be interested in trying a Jitterbug if I were using a USB connection, but I am using an eSATA connection.

    Proud and loyal citizen of the Digital Domain and Solid State Country!
  • erniejade
    erniejade Posts: 6,321
    Got ya. I don't think they make a filter for that or if they do, I haven't researched it.
    Klipsch The Nines, Audioquest Thunderbird Interconnect, Innuos Zen MK3 W4S recovery, Revolution Audio Labs USB & Ethernet, Border Patrol SE-I, Audioquest Niagara 5000 & Thunder, Cullen Crossover II PC's.
  • BlueFox
    BlueFox Posts: 15,251
    An interesting side note is that I use a direct attached USB drive to my Lumin S1. In fact, it was the same one as I used on my Bryston BDP-1. This was a 500GB Toshiba. I ended up filling up this so I bought a 1TB Toshiba USB to replace it. Anyway, as soon as I attached it and turned it on I swear it sounded better than the 500GB drive. LOL.
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  • machone
    machone Posts: 1,510
    My understanding is that USB is not always bi-directional and if unidirectional it would make error correction impossible. I don't know about eSATA but in both cases it would be better to prevent errors that correct them. Ultra quiet/ultra fast power supplies will help prevent errors.
    Mojo Audio Illuminati v3>>Quantum Byte w/LMS>>Rpi/PiCoreplayer>> Starlight 7 USB >> Mojo Audio Mystique v2 SE>>ModWright SWL 9.0 SE Signature>>Hafler DH-500 Amp+ (Musical Concepts Fully Modded)>>
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  • Absolute_Zero
    Absolute_Zero Posts: 72
    edited March 2017
    I'm running a WD My Cloud NAS with 4TB ($150), Linksys EA3500 (AC750) $19, USB AC600 with 2dBi antenna $14). So I have no physical connection to worry about, no noise due to fans etc...

    The EA3500 is in WAP mode on it's own Channel and SSID and it's been solid.

    Using JRiver and during playback I can even put the wireless into airplane mode and the music still plays for up to 20 seconds. Been a very solid and transparent setup.

    Though for 4K content it's not cutting it so I have a wired connection pulled.
  • GospelTruth
    GospelTruth Posts: 403
    @DarqueKnight. I am always impressed with the thoroughness of the reviews that are presented.

    First, if all your music is on only one drive, I would make sure you have a backup of all that on another 2TB drive. Nothing is worse than losing everything when a drive unexpectedly goes bad - especially after all the work you've done to convert your rare vinyl to digital. Or you could work on setting up a NAS with mirrored RAID to help in that regard.

    After reading the review and some of the comments it appears that it would be hard to pinpoint just what makes one enclosure better than another. There are several factors I would think that could contribute:
    • Power supply (as stated)
    • Electronic parts in each enclosure. Some may use better parts than others, but hard to tell unless you evaluate the parts.
    • I can't say that the temperature of the hard drive is a contributing factor unless you had two of the same enclosure and put a heater (or airconditioner) next to one to make it warmer (or cooler) than the other and then did a listening test. However, lower temperatures tend to contribute to a hard drive lasting longer.
    Always a good read even though sometimes it's not obvious to me why data travelling over a USB or eSATA cable would sound different. (Same thing when you reviewed different CD-Rs for sound quality upon playback). I'm a computer guy and not an electrical engineer - so how electronics colors digital transmission and therefore affects the sound is currently beyond my understanding.
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  • I've managed backup by using Amazon Unlimited Cloud Drive. My entire collection is in the cloud.
  • Paradoxex
    Paradoxex Posts: 189
    Small technical note- the first pic of the hard drives and the description beneath do not appear to line up.

    Interesting read.
  • DarqueKnight
    DarqueKnight Posts: 6,765
    Paradoxex wrote: »
    Small technical note- the first pic of the hard drives and the description beneath do not appear to line up.

    Interesting read.


    You are correct. Thanks. The first sentence under Figure 1 should have been written:

    "Hard drive enclosures left to right: Sabrent EC-UEIS7 (fanned) $26, Rosewill RX304-APU3-35B Armer $36 (fanned), Vantec NexStar3 NST-360SU-BK (fanless) $30".

    I have asked a mod to make the correction.
    Proud and loyal citizen of the Digital Domain and Solid State Country!
  • DarqueKnight
    DarqueKnight Posts: 6,765
    First, if all your music is on only one drive, I would make sure you have a backup of all that on another 2TB drive. Nothing is worse than losing everything when a drive unexpectedly goes bad - especially after all the work you've done to convert your rare vinyl to digital.

    I have multiple backups including offsite storage.

    Proud and loyal citizen of the Digital Domain and Solid State Country!
  • tophatjohnny
    tophatjohnny Posts: 4,182
    The USB route is Okay and the Rosewill is a good unit. Once I realized 2TB is the largest size my Stream Magic 6 as well as my Onkyo receiver will allow, it was then I went NAS and besides seeing this thread, never looking back. Plus, it's nice seeing the Album artwork when the music is playing that you can have with using UPnP VS: USB, (as long as I am still blessed with sight) ! As far as noise....I can't hear a peep with my Synology DS215+ NAS.
    "if it's not fun, it's not worth it & remember folks, "It's All About The Music"!!
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  • K_M
    K_M Posts: 1,629
    DSkip wrote: »
    stevep wrote: »
    In the digital domain any changes in the data would be detected as read errors so what do you propose is the cause of the differences you heard?

    Like most components - noise floor. This noise carries through the chain. The signal or read errors isn't an issue.

    Jitter also plays a significant role but I'm not sure that was an issue here since the only variable was the HD enclosure.

    Not exactly. Unless you completely negate the human variable. Error/perception/bias and all that stuff.

    If one is aware of what they are using/listening to, they become a variable also.
  • DSkip wrote: »
    stevep wrote: »
    Jitter also plays a significant role but I'm not sure that was an issue here since the only variable was the HD enclosure.

    My understanding of Clock Domain boundaries and Asynchronous FIFO is that jitter on the SATA bus should be a non-issue due to multiple copy stack nature of consumer operating systems (even ones used on purpose built streamers). A little bit of buffer goes a long way :-)

    https://www.youtube.com/watch?v=-EmFg3gCVs0
  • DarqueKnight
    DarqueKnight Posts: 6,765
    edited March 2017
    K_M wrote: »
    Not exactly. Unless you completely negate the human variable. Error/perception/bias and all that stuff.

    If one is aware of what they are using/listening to, they become a variable also.

    Personal bias is only a factor if the subject is not properly trained in objective evaluation. In these trials, I had the following personal biases:

    1. I prefer solid state drives because they are smaller, they produce no mechanical noise, they produce little heat, and they can be mounted inside my BDP-2 music server. The only thing I don't like about SSDs is the current very high prices, which are about 6X the prices of comparable capacity hard drives.

    2. Prior to the evaluations, of the three hard drive enclosures evaluated, the Rosewill was my personal favorite due to aesthetics, build quality, low level of mechanical vibration, digital display of temperature and fan speed, and fan quietness. However, my personal favorite, the Rosewill enclosure, came in last place when evaluated on the basis of the stereophonic sound quality of digital files played from it.

    There are some people who erroneously believe that people cannot be trained to objectively ignore their personal biases. However, the concept of the "debiased consumer" is a long-standing area of research in the field of economics. It concerns methods by which a consumer must train themselves to objectively evaluate economic and functional value rather that aesthetic and other personal preferences. For example, there are some people who would purchase a home simply on the basis of the home's size, appearance, features, and location. A person trained in objective evaluation of homes would also consider things like maintenance costs, structural integrity, appreciation of homes in the area (future resale value), likelihood of natural disasters (fire, flood, weather, etc.), and proximity to environmental hazards.

    Another example is the area of mate selection. Some immature people choose a spouse simply on external factors such as physical appearance and income. However, those two factors are not attributes on which a long term relationship should be based. Important things such as character, integrity, personality, common interests, lifestyle, and genuine interest by both parties will determine the long term success of the relationship.

    For reference:

    "Training can effectively debias decision makers over the long term. Training, to date, has received less attention by academics and policy makers than incentives and nudges because initial debiasing training efforts resulted in mixed success (see Fischhoff, 1982 in Kahneman et al.). Decision makers could be effectively debiased through training in specific domains. For example, experts can be trained to make very accurate decisions when decision making entails recognizing patterns and applying appropriate responses in domains such as firefighting, chess, and weather forecasting. Evidence of more general debiasing, across domains and different kinds of problems, however, was not discovered until recently. The reason for the lack of more domain-general debiasing was attributed to experts failing to recognize the underlying "deep structure" of problems in different formats and domains. Weather forecasters are able to predict rain with high accuracy, for example, but show the same overconfidence in their answers to basic trivia questions as other people. An exception was graduate training in scientific fields heavily reliant on statistics such as psychology."

    Experiments by Morewedge and colleagues (2015) have found interactive computer games and instructional videos can result in long-term debiasing at a general level. In a series of experiments, training with interactive computer games that provided players with personalized feedback, mitigating strategies, and practice, reduced six cognitive biases by more than 30% immediately and by more than 20% as long as three months later. The biased reduced were anchoring, bias blind spot, confirmation bias, fundamental attribution error, projection bias, and representativeness."


    https://en.wikipedia.org/wiki/Debiasing

    By definition, the evaluation of stereophonic sound requires a listener who is objectively trained in evaluating the spatial and quality aspects of a three dimensional sound field. Since the evaluation of stereo sound is an exercise that requires some training and experience, it is silly and uninformed to pose that such subjects can be swayed by sighted trials and personal bias when the only subjects that should be used are those that have been trained to ignore aesthetics and personal bias and objectively evaluate on the basis of performance.

    Saying that people must do audio evaluations blind because that is the only way to avoid bias is as silly and misinformed as saying people must choose mates blind because that is the only way to avoid being swayed by powerful influences such as physical appearance, popularity, and income/wealth.

    I presented a historical overview of stereophonic blind testing here:

    http://forum.polkaudio.com/discussion/104973/a-historical-overview-of-stereophonic-blind-testing/p1

    (Note: the author's name that is censored by the forum's software is Stanley L i p s h i t z)

    A historical overview of subjective stereophonic evaluation, using objective criteria, was presented here:

    http://forum.polkaudio.com/discussion/104701/a-survey-of-early-stereophonic-system-subjective-evaluation
    Proud and loyal citizen of the Digital Domain and Solid State Country!
  • K_M
    K_M Posts: 1,629
    K_M wrote: »
    Not exactly. Unless you completely negate the human variable. Error/perception/bias and all that stuff.

    If one is aware of what they are using/listening to, they become a variable also.

    Personal bias is only a factor if the subject is not properly trained in objective evaluation. In these trials, I had the following personal biases:

    I read your quite lengthy reply, and while interesting, I am still convinced you are a human being. :)

    You are telling me you have no normal human reactions to a music/equipment comparison, yet are a human being doing the comparison, by yourself and controlling all the variables.

    I get it was just a fun "comparison", do not mean to belittle the extensive work you did and the time involved, but if you are aware of which unit is "being used", then you are not effectively removed from the test, but are another variable.

    Kinda like comparing sodas and seeing the labels.
  • lightman1
    lightman1 Posts: 10,789
    Ray is an emotional android. He dreams of electric sheep. He exhibits human traits but has the cold calculation of a Phillip K. Dick novel character.
    Only wondering why his creator never gave him the ability to feel.
  • ken brydson
    ken brydson Posts: 8,772
    lightman1 wrote: »
    Ray is an emotional android. He dreams of electric sheep. He exhibits human traits but has the cold calculation of a Phillip K. Dick novel character.
    Only wondering why his creator never gave him the ability to feel.

    I'm offended by your Dick reference ...

  • Saying that people must do audio evaluations blind because that is the only way to avoid bias is as silly and misinformed

    I would say that doing bias controlling for a large N would be more efficient than attempting training same said group IMO.



  • lightman1
    lightman1 Posts: 10,789

    Saying that people must do audio evaluations blind because that is the only way to avoid bias is as silly and misinformed

    I would say that doing bias controlling for a large N would be more efficient than attempting training same said group IMO.



    Training a group?
  • txcoastal1
    txcoastal1 Posts: 13,300

    Saying that people must do audio evaluations blind because that is the only way to avoid bias is as silly and misinformed

    I would say that doing bias controlling for a large N would be more efficient than attempting training same said group IMO.



    Have you ever had a conversation and evaluation from an orchestral conductor, or even a trained orchestra musician?

    They are trained to hear things most people except like minded or enthusiasts.

    Have had many sit ins listening to music even with me, myself, and I. I have Multiple rigs. There are times where we point out attributes of selections, or I discover something in a passage that I have never realized before. Take those passages/songs to other rigs and they may sound better, or may not really be accentuated at all.

    It is very important that you know your favorites in music, and have heard them at there best to really critique.
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