Quest for silence: Quiet SATA notebook hard drives

When using a notebook computer for audio applications, unfortunately it isn’t simply a matter of buying the most reliable big hard drive. Using a notebook with either a Software Defined Radio (SDR) or as a playback device when recording from external components (such as a tuner) means noise matters. Hard drives produce noise which affects concentration in critical listening applications where the signal to noise ratios are critical… especially with ‘compromised audio’, which is often characteristic of weak radio signals or old recordings.

Noise Factory © 2010 Alexander Marco

Hard drive evolution

The differences in hard drive technology are often quite obvious. Even within the last 15 years, the average person can readily compare old 3.5″ IDE hard drives to modern ones and notice the mammoth difference in audible noise, even with the software inactive (idle mode). More recently, there is often a noticeable difference between SATA drives with their increasingly rare IDE counterparts.

A decade ago, New York inventor Neil Singer suggested:

The level of noise in a disk drive is due to vibrations at particular frequencies, such as 6.6 KHz, 6.0 KHz, 5.0 KHz, 4.2 KHz, and 1.3 KHz. On the other hand, mechanical vibrations, which reduce seek time, result from vibrations at different frequencies, such as 3.3 KHz.

Today, Solid State Drives (SSDs) are generally considered to be ‘silent’ storage technologies. Problem solved, right? Perhaps, provided one has inordinate wealth! The cost associated with buying a huge SSD means these aren’t necessarily cost effective choices for radio DX applications where uncompressed audio demands may be onerous; a 6.14 MHz ‘spectrum chunk’ may consume as much as 120 GB of data per hour.

Research aids

For specific needs, the Silent PC Review (SPCR) test articles and forums are an invaluable, simple to understand resource in the quest for finding quiet hard drives, whether external, internal, desktop or laptop variants. Further, hard drive manufacturer Western Digital (whose part reliability is top notch) provides acoustic specifications in dBA on their website. Other manufacturers such as Hitachi & Seagate may also provide this data.

Much of this information (sadly, including this article!!!) becomes redundant quickly after publication. Before committing to recommended drives, it is prudent to check with manufacturers that there are not better performers that may have just been released.

Eventually the cost of SSD technology may become so affordable that it is foreseeable that there will be negligible demand for acoustic tests on the subject matter of this article. The reality is that SATA drives are older, less efficient performing drives but for now, remain perfectly appropriate choices. Drew Riley of Tom’s Hardware portal suggests:

Even though SSDs only account for 10% of the total market, growth over the next few years is expected to be explosive.

WD 2.5″ SATA drive © 2011 Matt Kieffer

Needs analysis

This blogger wanted to buy a 2 TB hard drive for a new notebook which is already furnished with a single 1TB (5400 rpm) drive, which incorporates a second bay for a secondary hard drive. SSD drives were not considered due to cost; a typical 1 TB drive costs over $600 and over half that for 0.5 TB. Although fast, external USB 3.0 drives were also not considered due to already congested desk space. Hell, there’s enough crap lying around!

Whilst affordable, those desirable 2TB SATA drives are typically considerably noisier than their smaller capacity counterparts. So significant was the increase in noise (based on the dBA specifications) this prompted a reassessment as to whether bigger was necessarily critical for the particular SDR application. If the noise is problematic, even if there are two internal bays, it’s not so easy to switch internal drives off unlike an external drive. Therefore it’s probably worthwhile to research the most appropriate internal drive, rather than be forced to tolerate a noisy drive by judicious use of headphones or a proportionate increase in playback volume!

Three top candidates

Priced from $45 including domestic shipping:
Western Digital Scorpio Blue 0.5 TB with SATA 6 Gb/s interface (WD5000LPVX)
Manufacturer specifications (dBA): idle 17, average seek 22.

Priced from $62 including international shipping:
Western Digital Scorpio Blue 0.5 TB with SATA 3 Gb/s interface (WD5000LPVT)
Manufacturer specifications (dBA): idle 17, average seek 22.
This drive won the Editor’s Choice at SPCR.

Priced from $125 including domestic shipping:
Western Digital Blue 1 TB (WD10SPCX)
Manufacturer specifications (dBA): idle 20, average seek 21.

One of the quietest 0.5 GB drives, the WD5000MPCK (idle: 15, seek: 17) was unfortunately no longer readily available. Obviously, when reading the dBA specification, lower is quieter. To convert between acoustic units please use the calculator below. It seems that manufacturer Seagate for example, cites noise measurements using bel units rather than dBA.

 

Further reading

Acoustic unit calculator

Advanced PC silencing

Benefits of Solid State Drives

Eight different 2TB hard drives, with dBA measurements

Home Studio construction

Silent Windows laptops?

Things you can do to have older laptops quiet again

Top 5 external A/V-rated drives for audio recording

World’s quietest (desktop) computer

Recording with consumer soundcards

When consumers record from analogue sources on their computer, the sound quality of the soundcard may be forgotten. Five years ago, a soundcard was purchased as a elementary step-up from Chinese soundcards integrated into a computer’s motherboard. Whilst it is rarely used, let’s crudely examine its relative quality.

This old Yamaha DS-XG YMF724 ($60) soundcard uses the SigmaTel STAC9704 / STAC9707 integrated circuit which yields a Signal-to-Noise Ratio (SNR) of typically 87 decibels (A-weighted). The minimum figure is 75 decibels. Total Harmonic Distortion (THD) is 0.02 percent. These measurements are made when the soundcard is being used with an analogue line-level input using its Analogue to Digital (A/D) converter. The accuracy of the A/D conversion is paramount whether one uses a portable digital recorder or a soundcard.

This soundcard will be compared to a more expensive M-Audio Audiophile 2496 soundcard (pictured below), based on the AK4528 integrated circuit. The M-Audio card offers a 95 decibel SNR and THD of 0.001 percent. This card costs $108, as does the Zoom H1 portable recorder with uncompressed recording from line-in (or microphone) onto a microSD card! For that sort of dough, the logical choice seems clear.

How important are these specifications? According to electrical engineer Richard Kuo:

A common way to measure the “cleanliness” of the output of a card is the SNR… SNR is measured in decibels (dB) and the higher the number, the cleaner or better the signal is. Above 90 dB is generally quite good and below 70 dB is getting down there. SNR measurements are usually only useful if you can make sure that all the measurements were done identically. Unfortunately, that’s rarely the case with sound cards. SNR figures from the manufacturer should probably be considered suspect. Your best bet is to figure out what the popular opinion about the soundcard you are considering is.

According to computer scientist Dr Qingkai Ma, inferior cards have a SNR of “30 to 50 decibels” whilst the “High-end range [is] 96 to 100 decibels”. He recommends Audio Win Bench to benchmark a soundcard.

Unfortunately, the Yamaha soundcard resamples to 48 kHz. Digital artifacts (arguably as problematic as analogue distortion) can be a byproduct of poor resampling. On this card, analogue recordings must be resampled from the fixed 48 kHz to 44.1 kHz (used in the compact disc) for the recording. The Professional Music PC website explains this phenomenon in layman’s terms:

The audio codec or engine of the card is “rate locked” to 48khz. This means that the card resamples everything to 48khz for the dsp/codec chip on the soundcard. This is a big limitation in a card because it means if your recording in 44.1 the audio is at least resampled to 48khz once on the way and and another one the way out through the card to your ears. This also applies to the digital IO as well as the analog IO, in fact the digital output on any [Creative Labs’ Sound Blaster] or ac97 card will be rate locked to 48khz meaning its impossible to output a digital signal to a stand alone cd burner at 44.1 or [Digital Audio Tape] machine or many other products which may need 44.1khz spdif.

There’s many other downsides to this resampling besides just a downgrading of the audio’s quality. Some people complain of timing problems in some software ie overdubs drift out of time and sync errors are just a few. Cards which resample generally speaking have a much higher CPU load on the computer as bus mastering is not used with these cards.

iXBT Labs is a Russia-based website dedicated to reviewing all kinds of computer hardware. Tester Maksim Lyadov revealed good audio performance with a substantially-identical OEM variant of this card, the Aopen AW754. This suggests the Yamaha consumer soundcard may provide satisfactory performance.

Whilst no primary reference is provided, Wikipedia contributors also contend that the Yamaha DS-XG YMF724 soundcard was not of poor quality:

Relative performance was good despite the typical low cost. The cards were usually equipped with good quality 18-bit Digital-to-Analogue Converters, providing similar low noise and harmonic distortion levels to those found in semi-professional hardware.

From a casual comparison of the specifications alone, there seems little doubt that audible differences from the original source will creep into the recordings undertaken on any consumer grade soundcard.

FM enthusiasts will be acutely aware of the amount of junk any computer spills into the FM band! Potentially, this flood of noise has an effect on the soundcard too. According to Richard Kuo:

The fact is, your PC is an incredibly hostile environment for a soundcard to be in. All that electromagnetic noise is bad news for a soundcard just trying to get a clean signal in or out of your system. Basically, what this all means is that in order for a soundcard to be true to the original sound, it not only has to have good hardware, it also has to be properly shielded.

In closing, the solution seems simple. Avail yourself of the above medication and you will have full confidence in your recordings! Hmmm… If only life was that easy…