OK...Added 2 HSU ULS-15Mk2 subwoofers To My System

After unboxing , I put one next to each speaker on the outside edge just to get started.
Followed the directions to get a base point on adjustments and then I listened to a couple of very familiar  Lp`s

I found that these subs are VERY distracting.....In a good way 
Naturally (at least to me) when someone adds a couple of 15" subs to a setup they have a tendency to focus their attention on bass and all that.
But I was hearing  many new sounds and DETAIL too that I had never picked up on before.
These sounds are not 'bass territory'... how does a Triangle image so much further out to the side now ?  

The next morning I dragged my Adcom 575 CD player from the garage system and powered up the subs only and put the RHCP`s Californication on repeat for about 12 hours or so.

Then did the crawl and moved the subs around and listened on and off over a week or so and then did another crawl and made changes to the settings on the subs too.
Getting better for sure. I think HSU recommends 30 hours for break in.

So far I absolutely love these HSU subs for what they are doing for my music !

I`m also finding that the numeric volume display on the Tortuga Preamp is down a bunch from my usual levels.

So, I now have 3 15" sealed subs in the room, the HSU`s and my Revel Ultima 15

Lindsey Stirling's` Shatter Me' has never sounded so good !

Mo subs is mo betta.

When the bass is lacking we tend to turn the volume up more. That's because we don't hear low bass with anywhere near the sensitivity we hear midrange and treble. See: Fletcher-Munson curves. Now you no longer need to over-drive the rest of your system trying to make up for the lack of bass, you're able to turn the volume down and still be satisfied. 

Some of our sense of space is derived from very low frequencies. The waves of low bass are so long, 40 ft and more, they are associated whether we know it or not with large spaces. Adding the subs got you to where now those low frequencies are finally being accurately reproduced. This creates the sense of space that accounts for why your stage seems so much wider now. 

I hereby christen ye scm, DBA. Go forth and spread the Gospel!
millercarbon    Makes total sense to me Chuck !
I`m laughing at that last sentence btw ...:) :)

Welcome Sir scm DBA  to the multiple subs believer club:-)I've got four myself.
millercarbon    Makes total sense to me Chuck !
I`m laughing at that last sentence btw ...:) :)

That's great. A good sense of humor will come in handy. If you like bass try Bela Fleck Flight of the Cosmic Hippo.
It always makes me chuckle when I hear people say that the hate subs,or there is no need for them. I think to myself that they obviously have no need to hear all the music. But hey,it’s a relatively free country. 

868 .... :D might add another...never know

millercarbon ...I get that on the humor thing ! 
Not really a bass guy, at least I wasn`t !
I`m really a 99 % vinyl guy not sure if that is available on vinyl. Is that a Flim and the BB`s deal ?
I have a CAL tubed player that I need to plug in, now that I think about it, just to wake it up.

rocray ...Yep

Bela Fleck is on vinyl https://www.discogs.com/sell/list?master_id=101431&ev=mb&format=VinylI had one for $30 in my cart but was on the fence and since then wished I got it. But not for $60! Its out there though, somewhere. Music and recording quality is pretty good but that one track is just the best bass ever. Well I say that because one time I played it for this speaker designer, the guy had rows and rows of records and CDs, had designed a really good sub, and said it was the lowest cleanest bass he ever heard. Pretty good music too. Find it on YouTube or whatever. But be aware the bass is so low in one part you will only hear it with your DBA!

Awesome!  Enjoy.  I’ll be getting more subs as I can.  Bass completely transforms the music.  I think that almost anyone on this forum would want it if they actually heard it on their systems...
I've got the ULS-15 MKII and it's a musical sub, so I'm not surprised the OP is finding more detail.  It's gotta have the best bang for buck in a 15 inch, since they upgraded it.  

Congrats on the addition!
Hello scm,

    I also want to officially welcome you to the 3-4 Sub DBA Club, "where near state of the art bass performance becomes a routine reality in any room and with any pair of main speakers you prefer."
    I didn't consider myself a bass-head either until I began using a 4-sub Audio Kinesis Debra DBA system in my system and room. Now I consider myself more of a bass connoisseur because I'm now able to hear the details of pitch, texture, initial impact, changes in volume and natural decays of all of the separate bass instruments in the soundstage clearly on all music tracks. It really adds to the realism and enjoyment of all types of music for me because I can identify and clearly follow any instrument's bass line I prefer to.  I'm not exaggerating when I state the 4-sub DBA is the best single upgrade I've ever experienced in any of my systems over the past 50 years.  
    I still believe we can describe to others how remarkably well this 3-4 sub DBA concept actually works in practice until we're blue and convince very few. But ironically, we all know about a 10 minute personal audition would convince virtually anyone.  Plus it works in any room and with any main speakers, even notoriously hard to integrate fast speakers like planar-dynamic and electrostatic types.
    I understand they don't know what they don't know, but I thought more members would be adventurous and daring enough to at least give it a try. Oh well, I guess a lack of adventure and ambition results in a lack of very good bass resolution and a lack of daring results in the apparent lack of caring about the absence of high quality bass performance.


I've long considered most systems I've heard to sound too lightweight, lacking the heft and visceral qualities heard in live music. That lack of weight is accompanied by a lack of lower-midrange/midrange tonal density: instruments are robbed of their full, complex timbral character, sounding anemic, eviscerated, "washed out". It's analogous to lack of full color saturation in photography.

I find the fact that the lower few octaves contain SO much information in such a limited range of frequencies: the bottom four octaves cover only frequencies 20Hz to 320Hz, a span of 300Hz; the top four octaves 1280Hz to 20,800, a span of 19,520! Interesting, ay?

I understand they don't know what they don't know, but I thought more members would be adventurous and daring enough to at least give it a try. Oh well, I guess a lack of adventure and ambition results in a lack of very good bass resolution and a lack of daring results in the apparent lack of caring about the absence of high quality bass performance.

As I'm sure you know, this was all new to me a year ago. Its almost exactly one year now, maybe a little more, I first learned about DBA right here from you and Duke.

Back then I was just like everyone else, maybe a little better understanding of room modes and acoustics but like everyone else stuck in the one sub rut. Only real difference being I had tried hard enough to know one sub cannot work, not the way we want it to anyway, and given up. All the evidence seemed to say its impossible. By that I mean not only that one sub cannot work, but that there was no solution. I was convinced and had resigned myself to this. 

So there was probably not a tougher customer than me. 

And yet, when Duke congratulated me on having the faith, or however he put it, to do this, as nice as he is I had to set him straight. It wasn't a matter of faith. There was no faith- or daring, nor risk, or doubt. Because the situation- the physics and the psychoacoustics- had been so beautifully explained by guys like you and Duke, and Geddes, et al. 

You guys put it all right here on this site. Sitting right there for the taking. And take I did! Read it all. Then went and built it. Because boy did I have the desire. Or as you put it, care about the absence of high quality bass performance. It had been in my estimation the weakest aspect of an otherwise compelling and very satisfying system. 

Which in one fell swoop went from weakest link to arguably the strongest. In a system that over the same year improved immeasurably across the board. That is huge. Transformative. All thanks to you guys. Well, okay, and a little initiative on my part. But I couldn't have done it without you.

Hello millercarbon,

     I remember you as being very interested in improving the bass performance in your system and room.  But also a bit frustrated with the sub solutions you had tried up to that point.
     I think you deserve credit for having an open mind, understanding well what Duke, myself and others were stating about how and why the 4-sub DBA concept was so effective and doing your own homework online about the principles underlying the concept.  You also had an adventurous spirit to not only give it a try, but you had the knowledge, ambition and wherewithal to go even further and build your own custom 4-sub DBA with upgraded drivers.
     Sure, you had a bit of help but, from my perspective, you deserve most of the credit for your own success and you earned the extremely good bass performance you can now enjoy daily for a lifetime.  I think it's also admirable that you're also now a very good advocate of the DBA concept and you consistently and constructively help others improve their in-room bass performance by sharing your knowledge and experience with the concept

Congrats and enjoy,
. b_limo ..Thanks. I think if you added a sub/subs it would be one of those 'Why didn`t I do it sooner ' type things :) 

erik_squires ..I can see why. I actually had a HSU sub years ago that I sold to my buddy and he`s been using it ever since.

213runnin ..Very musical and the best sub out there for the money comment is heard a lot. Thanks

noble100 ...Thanks Tim. I agree across the board. My buddy who I sold my HSU sub to years ago came over to hear the new subs Tuesday night.
He and his wife are audiophiles also. I filled him in on what I was hearing before putting anything on. He`s a bit of a skeptic though.

He went over to the rack and pulled a couple LP`s that he wanted to hear.

The first cut wasn`t even over before he was saying things like "Did you just hear that ?!"  
It wasn`t anything special..Tracy Chapman I think.
After the listening session was over he said it was the best $1700 improvement he`s ever heard !
He left a believer now too.

bdp24 ...You know it and I`m on board with your observation 110%

millercarbon ..Cool read Chuck ! Thanks for sharing :)

Thanks for the reply`s guys

Tracy Chapman is one of many records that has all kinds of unexpected little low bass treasures. Most common is when the bass player slides off the note at the end. There's a music term for this for sure but its like they slide their finger off at the end so the note trails off and at the same time its dying out its diving deep into subterranean bass. Without the subs it sounds like the note just goes a little deeper as it fades off but with the DBA even faint low bass is so clear you feel that and its freaking impressive. 

Everybody with a sub thinks they know what I'm talking about but only us guys with DBA really know, as I'm sure you now know very well yourself.