Review: OWC's ThunderBay 4 RAID 5 Edition
Trevor M. Carlee
Issue: June 1, 2015

Review: OWC's ThunderBay 4 RAID 5 Edition

MANUFACTURER: Other World Computing (OWC)

PRODUCT: Thunderbay 4 RAID 5 Edition

PRICE: $479.00

- Houses up to four SATA hard drives, SSDs or a mixture of both
- Can set up a RAID 0, 1, 4 or 5 array using SoftRAID
- Can configure the drive anywhere from 4TBs to 24TBs

I’m a huge fan of storage. Whenever I go into a computer store, I always peruse the hard drives section and convince myself that I need another drive. 
Needless to say, I have files on multiple drives spread out around my home and office. That’s why I started thinking about a more localized central storage unit that could hold a lot and also perform at great speeds. Enter OWC ThunderBay 4 RAID 5 Edition.

This little beast packs a powerful punch, with the ability to house up to four SATA hard drives, SSDs or a mixture of both. You can set up a RAID 0, 1, 4 or 5 array using SoftRAID, which also includes drive monitoring and email notification (alerting you of any issues).

You can configure the drive anywhere from 4TBs to 24TBs and it’s one of the few drives out there to take advantage of the speed of Thunderbolt 2.


The casing is black metal with a grill on the front much like the old Mac Pros (or the G-Raid hard drives, if we want to compare apples to apples). On the back you’ll find two Thunderbolt 2 ports for daisy chaining, a Kensington lock slot, a power switch, a large fan and a power plug. The power supply is internal, which means no power brick! 

The front panel has status lights at the top to indicate the status of each drive, labeled A, B, C and D, and one to indicate if it’s turned on. Additionally, there’s a lock on the front panel that comes with two identical keys.


I had my OWC ThunderBay 4 set up as a RAID 0 with 20TBs, which automatically eliminates 5TBs worth of storage. As most know, the more secure your RAID setup is, the less usable storage you have. I prefer security to size.

Currently, I have the ThunderBay storing 7TBs of 4K footage, and it’s showing no real delay when playing back the footage through AMA link in the Avid Media Composer 8.0 Symphony Edition. I also have a plethora of files, such as a 24-hour Web stream, Time Machine backups and software instrument libraries.

I initially had my instrument libraries on my main hard drive, as it’s an SSD and my machine is super fast (newest Mac Pro maxed out). That allowed for my instruments to load almost instantaneously. However, the number of libraries I own has reached such a massive level that it just took up too much space, so I had to sacrifice speed for space. 

Additionally, I did the “dangerous test” of pulling out a drive while it was being read — and luckily everything continued as it should have. 


As for the nitty gritty, instead of telling you how many MBs per second this thing can read and write (visit the company’s Website), I’m going to give you some real world numbers. My first big test was my music libraries. The first batch was about 215GBs. I transferred these from my Mac Pro’s SSD directly to the ThunderBay. I started the transfer and it said it would take “about an hour” to copy. It was about a 54-minute transfer for 215GBs. That’s pretty slow, considering it should have taken about seven minutes if the drive actually had a write speed anywhere around 500MB/s. 

My second test was the 7TBs of footage mentioned earlier. This was transferred from a G-Raid (which has Thunderbolt 1 capabilities). When I started the transfer, it told me it would take about 12 hours, and it did take that long. It also started making some weird clicking sounds a few hours in. I was perplexed, as this was nowhere near what was promised for speed. Then I realized I forgot to install the $170 SoftRAID software that essentially enables the RAID to its fullest potential. Once I installed it, I was able to transfer 123.47GBs of music libraries in three minutes from my Mac SSD to the ThunderBay. Now that’s speed I can brag about!


The first downside is the price. It’s a bit steep for my taste. Plus you have to pay $170 for software to make it work correctly — now you’ve got quite the hefty bill. Also, there’s the noise, and this thing makes a lot of it. 


I love having 20TBs (well, 15TBs) of storage. I love not having to delete something or move things around. I can edit directly off of it, which is great considering my Mac Pro only has the one SSD and forces you to work off external drives. There’s the 3rd party software, and the sound is obnoxious, but I have found it incredibly useful.  

Trevor M. Carlee is a Post Producer with Bunim/Murray Productions in Van Nuys, CA. He can be reached at:


Eileen Millard (, product promotion and brand evangelist for Other World Computing commented on Trevor Carlee’s evaluation.

1) "Plus you have to pay $170 for software to make it work correctly…”

Two things here: Although the standalone price for buying SoftRAID 5 software alone is currently $179, OWC offers bundle pricing that reduces the cost considerably, to only $64. That is the difference between a 20TB ThunderBay 4, SR 5 version ($1,479.00) and the 20TB ThunderBay 4 JBOD version ($1,415.00)
As to the ThunderBay 4 only "working correctly" when the SoftRAID 5 was installed: we offer the ThunderBay 4 in two options, one with SoftRAID 5, and one without, to give customers more choices. Depending on the type of work most commonly done, some customers prefer a SoftRAID 5 option, some do not. But both options work correctly for what they are. 

The speeds you saw when initially running the ThunderBay 4 without the SofRAID 5 installed are correct for how the machine was being run, without the benefit of SoftRAID 5. But anyone who chooses a SoftRAID 5 model of the ThunderBay 4 (which includes the SoftRAID 5 software in a very affordable bundle price) and installs the SoftRAID 5, they will see the top speeds you reported you observed with SoftRID 5 installed.  

2) "Also, there’s the noise, and this thing makes a lot of it…” 

The majority of the noise from the ThunderBay 4 is from the hard drives themselves, and not from the enclosure itself. This is always going to be true when you use 3.5-inch hard drives. There are a few things you can do about the noise:
- When you don’t need to actively use the ThunderBay, you can use OS X to eject the drive and then either power it off or disconnect the Thunderbolt cable. 

- Using a longer Thunderbolt cable to move the ThunderBay 4 further away from the recording hardware will also help. This LINK shows Thunderbolt cable options available from OWC.