“Let our rigorous testing and reviews be your guidelines to A/V equipment – not marketing slogans”
Facebook Youtube Twitter instagram pinterest

HSU VTF-1 MK3 Subwoofer Preview



  • Product Name: VTF-1 MK3
  • Manufacturer: HSU Research
  • Review Date: November 13, 2016 18:00
  • MSRP: $399
  • First Impression: Gotta Have It!
  • Finish:  Satin Black paint
  • Front firing 10” driver with dual front firing ports.
  • 250w RMS, 1000w Short Term
  • Overall dimensions (HxWxD) 18.5" x 14.5" x 17”(excluding feet and grill)
  • Net weight 42 lbs.
  • Extension:  25Hz single ported, 32Hz double ported or sealed
  • Warranty:  7-years on driver, 2-years on electronics

Since 1991 Dr. Poh Ser Hsu, who received his PhD from MIT, has been developing amazing subwoofers at an affordable price among internet direct retailers.  Although they're not strictly internet direct since you can visit their office and showroom, make a purchase, or experience some demos at any time during business hours, most would still call them a force to be reckoned with among I.D. retailers  Every few years, many companies develop new products to appeal to consumers. HSU Research is among them, though they do not change their cost to performance ratio.  They recently discontinued their STF-2 and introduced a new product, the VTF-1 MK3.  Now HSU only has five subwoofers that they produce.  That seems like a short product line for an I.D. company as I could only think of a few other ID companies that have less subwoofers for purchase such as Outlaw Audio, Premier Acoustics, and NXG.  The VTF-1 MK3 is now $399 (a $60 decrease from the $459 it was in the past).  Shipping within the lower 48 states of the U.S. is $52, unless you purchase the sub at their office and pay no shipping cost.

VTF-1 mk3 front no grill main.jpg

So what do you lose for the $60 decrease? The satin black finish, which has been replaced with vinyl.  We think that's a great compromise for the cost savings, especially since you actually gain performance compared to the model it replaces.  The new VTF-1 MK3 model is now front-firing as opposed to the down-firing orientation of the previous model.  This is similar to what HSU has done with the VTF-3 MK5 versus the mk4 model.  The new VTF-1 MK3 has the same satin black paint finish as its predecessor as well as the same 10” reinforced paper driver.  The sub has a more powerful BASH amp.  BASH amps combine the digital efficiency and cool running of Class D amps and the sound fidelity of Class AB amps.  The VTF-1 MK3 has 250w RMS and 1000w peak power.  This is similar to or the same amp as their VTF-2 MK4, though the VTF-2 mk4 is larger with a 12” driver.  The older model VTF-1 MK2 had a 200w RMS and 800w peak BASH amp.  The plate amp has a pair of high level inputs one for right and one for left.  It also has a pair of RCA low level inputs, which you can use one for the single sub line input.  There are three knobs, which control volume, Q-Control, and the crossover setting.  There are also toggle switches that control Phase, Operating mode (EQ1, EQ2), crossover “in” or “out”, and power “on”, “off”, or “auto.”

VTF-1 mk3 amp.jpg

This dual ported subwoofer now comes with four rubber feet versus the plastic cone spikes of the older model.  It still has the hybrid technology that allows the user to customize the output and sound quality of the subwoofer based on personal preference and room characteristics.  The end-user can customize the performance by adjusting the Q-control knob along with adjusting the EQ switch.  When you adjust the Q-control knob, this adjusts the “tightness” of the driver which allows for more or less output depending on your room size and taste in sound quality. 

Caution: The only disclaimer HSU has with this is not to operate the sub with both ports open and the EQ switch set to EQ1 as this will damage the product and negate the warranty.

This subwoofer has a bass extension of 25Hz-200+kHz (+/-2dB).  One port mode has an extension of 25Hz and the two port/sealed mode extends to 32Hz.  The 32Hz two port mode is used if you have a fairly large room with no room gain or just want clean and loud mid-bass.  The 25Hz setting is used if you do not play very loud, but want deeper bass extension.  The sealed mode is meant for a smaller room that accentuates the bass due to room gain.  These characteristics are changed with the provided port plugs.  This is all explained in detail on HSU’s website or just give them a call and their great customer service reps will be glad to explain it to you.

VTF-1 mk3 rear.jpg

The one port mode at 25Hz may not sound that low to some, but if you have had experience with their subs like I have, then you'd know that in a room under 3000 cu. ft. (which is the recommended maximum room size for this sub according to HSU), this sub will most likely surprise you with the amount of output and power it can dish out.  This subwoofer should be able to produce pretty good usable output to about 20Hz and maybe even a little lower depending on the room according to the graph on HSU’s website. According to the CEA-2010 performance measurements posted on HSU’s website, in one port mode, the VTF-1 MK3 is rated at 100.2dB at 20Hz (1w/1m) as compared to the 94.9dB of the VTF-1 MK2 model.  Furthermore, with two ports open the VTF-2 MK3 is rated at 103dB at 25Hz versus the 93.9dB of the older model at the same Hz measurement.  Between 25Hz-31.5Hz with two ports open, the VTF-1 MK3 and VTF-1 MK2 average 108.2dB and 102.5dB respectively, which is a big difference and can make for a visceral experience whether you’re kicking back listening to some tunes or popping in your favorite action flick.  Depending on the tuning mode you choose to run the VTF-2 MK3, it hovers between our medium and large Bassaholic room size rating which is quite a feat for a sub of this price class!

My older model STF-2 with a 10” driver, is single tuned to 25Hz with 200wRMS and 800w peak (hence the name Single Tuned Frequency).  It gives an amazing response in my 2200 cu. ft. room, especially for movies.  I have had to dial it down a bit on the sub volume to about 9-10 o’clock.  It still gives a moving experience with room vibration at moderate volume levels especially with films like Godzilla (2014).  The STF-2 was basically the slightly smaller single tuned version of the older VTF-1.  The STF-2 is 17”H(19” w/feet) x 14”W x 17”D.  The new VTF-1 MK3 is 18.5”H(19.5” w/feet) x 14.5”W x 17”D(19” w/grill and amp knobs).  It also weighs in at 42lbs.  HSU also has a 7-year warranty on the driver and 2-year warranty on the amp.  They also have a 30-day satisfaction guarantee.


If you are looking for a strong performing high-end 10” sub that can rock a media room up to 3000 cu. ft. down to 25Hz (depending on the setting), then the VTF-1 MK3 might be the one for you.  Dr. Hsu and his “little” subwoofer company in Anaheim, CA are more than happy to assist you with any questions you have.  I know that everyone has their own opinion, but from my experience, they are very humble and understanding people.  They also are customer-oriented, as they do not try to up-sell you on something that you might not need.  As they say on their website, they are not like other companies that “sell the sizzle, not the steak.” To call the VTF-1 MK3 a “budget” subwoofer due to the fact that it is the least costly of their subs would be the only reason to call it that. After all, it is an HSU, they have been in business for 25 years for a reason.

Unless otherwise indicated, this is a preview article for the featured product. A formal review may or may not follow in the future.

About the author:
author portrait

Kevin is a blue-collar family man and A/V enthusiast who was introduced to music and movies by the age of five. He took courses on Film Music and Film History in college just for the heck of it along with receiving his BFA in Illustration from Cal State Fullerton. He grew up listening to music on vintage equipment, and soon took an interest in home theater.

View full profile