Upgrading sub to get a live feel.

I have a dual purpose main system using different amplification for pure audio vs. video, and use a pair of Hsu  VTF-15H MK2 powered subs for video only.

I have run the subs with the audio front end on occasion and they are very good indeed, not just for bass reinforcement with video. Note that they were installed using proper analytic instrumentation for location, configuration and tuning and not everyone has that available - if you just stick them wherever they fit in your room, YMMV.

wspohn:
"I have run the subs with the audio front end on occasion and they are very good indeed, not just for bass reinforcement with video. Note that they were installed using proper analytic instrumentation for location, configuration and tuning and not everyone has that available - if you just stick them wherever they fit in your room, YMMV."

Hello wspohn,

    Just to clarify for thread readers and prevent them from being discouraged or misled about incorporating one or two subs in their systems, I thought it was important to let them know the following about your post:

    While you're absolutely correct in stating that you can't expect to just stick one or two subs in your room wherever they fit in the room and expect to obtain good bass response, it's absolutely not true that they need to be installed using proper analytic instrumentation for location, configuration and tuning and not everyone has that available.
    Everybody has what's required, two ears and what's in between, and knowledge of the 'crawl method of sub positioning' to incorporate one or two subs in their system. Thread readers can refer to my previous posts on this thread or google "the crawl method of sub positioning" to learn more on the specifics of using this method.
    Your use of the abbreviation YMMV can also be misleading since their mileage will not vary. The science of Acoustics has established how the longer bass soundwaves behave in any room and this knowledge is baked into the concept and effectiveness of the 'crawl method'.
  The single most significant rationale for utilizing the 'crawl method', as an alternative to the more expensive and complicated method using analytic instrumentation, is precisely because your mileage will not vary and it can be relied upon to be just as effective in any room or system.
  I'm not claiming any of the above possibly misleading or discouraging language in your post was your intent, I just wanted to make sure a few points were clearly understood by thread readers and potential sub users.


Tim  
 

Right. As an example of just how well this DBA approach works, when my four were first installed all I did was plop them down facing the walls each one a little different distance from the corners. Instantly and without any adjustment the bass was deeper, smoother, faster and more articulate and dimensional in terms of imaging than anything I ever heard before. They have since then been tweaked down in level both dB and crossover frequency, and phase, all of it done by ear because even though I have a dB meter handy its the ears that rule.

Especially with bass. A lot of the problems people have getting this concept seem to have their roots in some really fundamental misunderstandings about how human beings hear and perceive different frequencies. We simply do not register timing with bass, for example, anywhere near the way we do higher midrange and treble frequencies.

In terms of level, meters and EQ fail to account for the way we hear bass volume. Look up Fletcher Munson curves. These graphs are not flat because unlike meters human beings do not respond to bass equally. The way we hear bass varies by volume. A lot. Look at the curves!

So as cool as it sounds and as much street cred as it might seem to get using EQ or meters or whatever other analytical doo dads one might buy, the truth is these things are more often than not used by people who don’t understand everything that is going on nearly as well as they think they do.

Go and listen. You will see.

millercarbon:
"Especially with bass. A lot of the problems people have getting this concept seem to have their roots in some really fundamental misunderstandings about how human beings hear and perceive different frequencies. We simply do not register timing with bass, for example, anywhere near the way we do higher midrange and treble frequencies."


Hello millercarbon,

     Yes, very good points about how we perceive bass sounds differently than higher frequency sounds.  
     We don't even perceive the existence of a deep bass tone sound in a room until the full cycle bass soundwave(a 20 Hz bass tone has a soundwave that's about 56' long) has been reproduced in the room, our ears have inputted the presence of a detected full cycle bass soundwave to the brain and our brain has processed this information as a perceived bass tone.  Any partial soundwave (less than a full cycle bass soundwave) presence detected and inputted to the brain is not processed as a perceived bass tone or any sound at all.
     Our brains also require the detection of multiple full cycle deep bass (below 80 Hz) soundwaves in the room to perceive a change in volume or pitch.  
     Another poorly understood aspect about how our brains process deep bass soundwaves below 80 Hz is the whole subject of psychoacoustics that come into play beginning with use of two subs and the main reason the 3-4 sub DBA concept works so incredibly well.


Later,


  


  
     

  

    

I was able to get the system to work and sounding good, that I didn’t want to mess with it for the evening. The solutions were I didn’t need to move any of the current front set up, they sounded great as they were, the JBL were made to not interact with the environment as much as other speakers, but I might be tempted in the future to move them. Two things that solve the lower mid range harshness was lowering the front subs crossover point to even lower. Bass response and imaging improved with the two new PB using the crawl method. They ended up behind the main seating position against the wall.

The SB front are set at 60Hz and the PB are set at 50 Hz
SB volume is at 50% and the PB volume is set at 35%.
Phase for all 4 is at 0.

Since it is all set now, i’ll play with the crossover points maybe a little more until I get the cleanest imaging.

Then I’ll try to push the volume up a little.

The results are larger sounding speakers, I went in with the expectation of wanting subs that created a lot of energy, if you’ve been to a proper set up room with big subs, you know how that feels. What I got from this set up was just larger speakers that are very accurate, detailed, and enhanced sense of space. It isn’t like a big game changer, but if you have a great sound going and want that extra headroom, this is a wonderful solution. It is a good incremental improvement for a very reasonable price, but I also got more value recapping the speakers. I also have a feeling that if you already have powerful speakers bass like B&W 8xx, this set up with small subs might not keep up. JBL have a very neutral bass and this fits.


As for demoing the 4367, I cannot say I can give a proper review of it. The place I went to had it set up for home theater, at 175watt per channel. The mids and bass were non existent. But to what I can hear. The 4367 have the JBL sound but just in large size. If you like the JBL presentation of music, the 4367 does them. The highs are extended and non fatiguing. I also can’t say it made me want to upgrade, as my current system sounds significantly better than what I heard, but it wasn’t a fair match. I can tell if the 4367 were done properly it would sound like what I have, but just bigger. Maybe when I have the itch to go larger, i’ll scratch, for now I am happy. I like JBL for their sound, I thought I could get significantly better sound as you go up, but the price to performance was not there.