The VTF3 is a little out of my price range right now.
1x VTF3 = $750 shipped vs 2x VTF1 = $1000 shipped
. Just kidding.
Would it make sense to get the VTF1 and at a later time get a second VTF1?
Here is an
AH article that talks about two lower output subs vs one higher output sub. It is an excellent writeup on this topic. In short, the primary benefit of adding a second sub is to get more even bass response across more listening positions. Contrary to popular belief, the second identical sub does not make a major impact to volume or how low the subs will play.
That said, one way adding a second sub will increase output is to stack both. To get the most of the stack, you will can keep it in a corner. As it happens, while corner placement is great for maximizing output, it is not very good for flat response across more locations. So the choices are, more volume in one or two seats or even bass with lower volume (assuming distortion is below audible level). The former is good for movies and the latter is better for music.
Now the task at hand. AH has reviewed both subs, so it is easy to compare them.
VTF1 vs
VTF3. So, can two VTF1s stacked equal one VTF3? Looking at the measurements page on both,
In max extension mode (aka play lower Hz at expense of higher volume)
1x VTF1: 80dB @ 15Hz
2x VTF1: 83dB @ 15Hz (stacked not in corner)
2x VTF1: 89dB @ 15Hz (stacked in a corner)
1x VTF3: 95dB @ 15Hz
1x VTF3: 101dB @ 15Hz (in a corner)
In max SPL mode (aka play louder at the expense of lower Hz)
1x VTF1: 102dB @ 40Hz
2x VTF1: 105dB @ 40Hz (stacked not in a corner)
2x VTF1: 111dB @ 40Hz (stacked in a corner)
1x VTF3: 107dB @ 40Hz
1x VTF3: 113dB @ 40Hz (in a corner)
That said, we are dumbing this comparison down to the point that it is a yes vs no. Unfortunately, we loose details like, how much flatter the VTF3 plays up to 100Hz (making it easier to integrate), you can add the 'Turbo' on the VTF3 and make it play even louder and deeper. Last but not the least, if the VTF3 is not pushed to limit, the distortion will be significantly lower than VTF1 (since the VTF1 will be closer to its limit).
Would you recommend any other subs? My budget for one is around $500.
SV Sound PB1000.