Velodyne MiniVee Measurements and Analysis

I measured the Velodyne MiniVee in my office space using the antiquated but accurate Linear X LMS measurement system.  No smoothing was used unless otherwise indicated.  I also used the new Dayton Audio OmniMic system to measure system distortion. 

Velodyne MiniVee Nearfield Frequency Response

I measured the MiniVee at various output levels using the groundplane technique at 3 inches from the front driver.  The output was scaled -19dB down to give the actual SPL output I could hear at my listening position which was roughly 4 feet away.  The subs highest output is centered around 50Hz but rolls off significantly below 30Hz where there is a deliberate HPF employed to protect the drive unit and keep things from getting ugly.  I was a bit surprised to see about 5dB of rolloff at 80Hz even with the subs internal crossover bypassed.  I could only surmise that the inductance of the large voice coil and heavy cone of this smallish driver was contributing to this phenomenon.  It certainly explains why I opted to use no bass management at all on this sub when mating it with my EMP 41-SE/B desktop speakers.

Unlike the MicroVee that drops off like a rock below 50Hz, the MiniVee has about a 10Hz true usable extension advantage.  I was able to hit 106dB SPL at my listening seat with this potent little sub which was about 5dB more output than I measured on the MicroVee at 50Hz and whole lot more below 50Hz as you will see in my comparative measurements below.  Velodyne claims the -3dB point of the MiniVee is 28Hz.  Because of the bump at 50Hz, it’s a bit hard to give an exact figure here.  I would say its more like 30-32Hz.  At high SPL however where the sub compresses and the limiter kicks in, we see a 38Hz -3dB point with about an 18dB/Oct roll off.  This is very respectable performance for a product smaller than a shoebox. 

I found it to be revealing to compare the output of the Velodyne MiniVee to the smaller but more expensive MicroVee model.  I tested both subs identically using in-room nearfield groundplane scaled to the listening position 4ft away.  

Editorial Note about Continuous Sweep testing vs CEA Burst Testing
Our sweep tests were conducted at a constant input level across the entire bandwidth whereas CEA burst tests are typically conducted at discrete frequencies (ie. 20Hz, 25Hz, …etc) by varying input voltage until max SPL per a fixed distortion limit is achieved at each test frequency.  Our tests reveal max SPL where the subwoofers begin to compress but there is typically more output left above the compression point of each subwoofer if the subwoofer under test is not amplifier limited. For more info on this, read our 2010 Subwoofer Shootout Measurements Overview article.

Velodyne MiniVee (left pic); Velodyne MicroVee (right pic)

As you can see the MiniVee pwnes the MicroVee below 60Hz with a whopping 24dB output advantage at 20Hz.  Only above 70Hz does the MicroVee exhibit appreciable (+3dB) more output than the MiniVee.  The MiniVee is just a whole lot more sub than the MicroVee but it's also almost twice the size.

Velodyne MiniVee Distortion @ Max Output

At moderate listening levels which would equate to about (81dB @ 40Hz) at my listening position, I measured under 1% distortion below 60Hz on the MiniVee.  It wasn't until I ran the sub to its max output that you could see distortion rise appreciably.  At 31Hz max usable output, I measured 17.68% which is actually quite excellent for a subwoofer driver.  Distortion below 30Hz dropped thanks to the HPF system limiter doing what its supposed to do to protect the driver and ensure you can't hear any audible distress.

I measured distortion of the Velodyne MiniVee sub used in conjunction with my EMP 41-SE/B bookshelf speakers as you can see below.

Velodyne MiniVee + Speakers System Distortion vs Frequency

If you subtract the frequency response curve (brown) from the distortion curve (blue), you can calculate THD +N. using the table below:

So in our case, above 200Hz we see 80dB SPL level - 40dB distortion level yielding 1% THD + N.  The overall distortion profile of this system from 20Hz to 20kHz is quite excellent which explains why I enjoy listening to my desktop system often moreso than any other system in my home.  It plays plenty loud and clean with great bass extension thanks to the MiniVee.  What else could anyone want from a desktop system?

 

Velodyne MiniVee + EMP 41-SE/B In-Room System Frequency Response
Green Trace: 41-SE/B; Red Trace: MiniVee + 41-SE/B

As you can see in the measurement above, my little EMP 41-SE/B speakers don't have much usable bass below 80Hz.  Adding the Velodyne MiniVee into the picture was like giving that system a shot of Red Bull.  With the MiniVee playing in my little office, I had true mid 20Hz extension at my listening seat.