Subs... Giving them another try

[Carlman]

OK so.. my basement project came to a standstill when I dislocated a finger and there's no better therapy than shopping, right?! haha.

Do I 'need' a sub... no.  Do I love bass? yes.  It gives emotion and impact to music that's very important to me, especially for rock.  However, it has to be very good bass... otherwise it sounds synthetic and completely ruins the emotion of the music... so, it's a tricky thing to get right. 

So far, I haven't heard too many subs I thought were 'good' or even 'good enough'.. I heard some VMPS huge stereo subs that I thought were pretty good... and a Piega sub that was really nice.  I could get a pair of Piega's but they don't exactly match... and while they're a good deal, I only want a matched pair of subs. 

I asked John at Black Sand about JL Audio subs because I'd read some good reviews.  He said nah.. and suggested looking into Rythmik subs.. I'd heard of them but wasn't sure.  John's had great results with them and I was wondering if anyone else had... They use an interesting 'servo' technology: http://www.rythmikaudio.com/technology.html

I'm thinking of getting a pair of sealed 12's for audio.  If I go this route, I'll probably get Brian Bunge (RAD) to build them.  I'll also get a vented 12 and build it into the platform under the seats for the .1 in 7.1.

I know nothing about crossovers at this point but I'm thinking that may be the way to go for optimum setup... Basically, I'd cut everything below 50?Hz to the Piega C8's and cut everything above 50Hz to the subs... Does that sound right?  Where's Doug S when I need him?

Thanks,
Carl

[Black Sand Cable]

You know my thoughts already so I will (more or less) stay out of this one.

I will say that the Piega's C8's are specified -3dB point of 36Hz so you could even look at 40Hz versus 50Hz but at the end of the day, there is no right or wrong. It will come down to the sound you like.

I'm also a big fan of dual subs. When you get them set-up right, it's an amazing experience to hear bass done right!

I have been a bass head for years now and have owned most of the mainstream products that are out there with mixed results. Once you get past the "Boom" it's amazing how many very highly rated subs just can't get music right.

[bpape]

I've heard very good things about the Rhythmic stuff.  The other one I'd seriously consider is ACI.  Mike makes some great stuff and some of the only subs I've ever heard that go deep, are powerful and tight, but still fast enough to keep up with things like Maggies (not an easy task for any sub).  I've heard a lot of very good subs fall flat on their face trying to blend with panels or all ribbon speakers. 

Bryan

[miklorsmith]

I forget, are you using a Mac preamp at the moment?  Do you have two separate line-outs?  Whether you want to filter your mains is a definite maybe (done that) but if you can precisely cross AND EQ your sub you're in for delightful times.  You have all the capability to do in-room measurements, pairing that with a full-on parametric EQ in the bass is THE way to go.

I'm running 40 - 120 hz on the mains and subs both but my mains are (deliberately) light in the power band.  There's no filtering on the mains.  Plus, my subs are co-located so I wouldn't assume this will work for everyone.

Bass isn't bass isn't bass.  Just because a manufacturer says their speakers go to a certain depth doesn't mean they do it well, it doesn't mean they do it flat, and it doesn't mean they do it with authority.  It also doesn't describe how they interact with your space or the rest of your gear.  It might well be that filtering the mains will free them and your main amp of tough duty (not that your Mac needs the help), which can realize benefits from the midbass on up.

John Potis' experience filtering/XOing mains 'n subs found here:

http://www.6moons.com/audioreviews/bryston2/crossover.html

He didn't go All The Way though, no EQ.

If you go the full-bore route which includes the bass EQ, it's a learning curve unless you already know how parametrics work.  I got a dbx unit which has a TacT-type computer interface which helps a ton to see what it's doing.  In my case, the EQ is only in the path from 120 hz down so I get the transparency of a "pure" path with the room-tunable benefits where they're really needed.

My Def. 2 review will go into much detail on this.

My personal, humble opinion is this is the only dependable way to get deep, flat, slammin' bass that musically integrates with the rest of the spectrum.  It surely is possible to get closer with room treatments which are always the first line of defense but even a treated room will not likely "fit" almost any real-world speaker without bass problems.  EQ won't fix all the nulls but it will give the capability to minimize them and level hump problems which are much more problematic.  I have found getting the bass "right" has positive effects throughout the sound spectrum and now I am very sensitive to bass irregularities.  Very, very few systems get bass right.

Imagine having your next issue be to figure out what in-room bass response curve you like best.  I have crossed that exact bridge and I can tell you it's a GREAT problem to have.

[Carlman]

I forget, are you using a Mac preamp at the moment?  Do you have two separate line-outs?  Whether you want to filter your mains is a definite maybe (done that) but if you can precisely cross AND EQ your sub you're in for delightful times.  You have all the capability to do in-room measurements, pairing that with a full-on parametric EQ in the bass is THE way to go...............................

I'm using a McIntosh C220 Preamp (with 3 sets of stereo preamp outs, main, 1, and 2) paired with a McIntosch MC402 amp. 

Looks like I'm in for a learning curve... From what I've experienced, the 'full-on' parametric EQ'ing is the way to go.  I do however, want something analog enough that I can dial it in and use with all sources.  I have a tuner and phono that will use the stereo subs.  So, if there is a device (like an eq) that can work similarly to the old school tape loop method, that'd work for everything.

I'm looking forward to the Def2 review.. sounds like I need to start learnin'.  Or better yet, ever think of taking a vacation to beautiful Raleigh/Durham NC?

-C

[miklorsmith]

Money's tight at chez Smith till the older kid heads off to kindeegarden.  Frickin daycare is damned expensive.  We really wanted to take the kids to Disneyland this year but it won't happen till next.   

If you go all-out, the EQ will take a separate feed off the preamp and you'll be able to use it for all sources.  My dbx unit has 100 presets for different venues (it's a pro unit) which can be different settings for TT, movies, acoustic tunes, whatever.

I'm only sketching on the review at the moment.  I have a feeling it's gonna wind up being a mutha and will probably take a while to write.

[Carlman]

Awesome, that's the direction I'll go, then.  I hope the money's not tight due to the EQ device.   How about some links to what you're talking about?  What's the setup basically consist of?  If you email me the components/parts/flow, I can draw a diagram and then post it to see if I 'get it'.

As to the actual subs, I have considered ACI... Mike is indeed a helluva guy and his room sounded really good last year at RMAF.  I'm not ruling them out.  I just thought the servo technology was kind of neat.

-C

[miklorsmith]

Nope, brokeness isn't because of the EQ.     I'm on a gear hiatus, good thing I'm not itching for anything.

Here's the one I have:

http://www.dbxpro.com/260/260.htm

This is one of the units Zu packages with their big speaks.  It's a 6-channel unit but only two channels are used.  It can do a pink-noise self-adjustment but if your using REW I think doing it manually works better.  It's definitely more transparent during the adjustment process.

No need to PM, it's simple.  One of your pre-outs goes to the main speakers, the other to the EQ which outputs line-level to the subs.  Most EQs will let you do stereo subs separately.

When I do my EQing, I use Room EQ Wizard from Hometheatershack.  I run one channel, then the other to get them individually dialed in.  The dbx allows individual, graphic EQ channels to do this at the primary stage.  I get them "pretty close", then go through a separate parametric stage with both channels playing.  This is the fine-tuning and the part where you can decide what you want in your room.  It makes tweaking a lot easier because you only have one set of adjusters and are starting from an essentially flat room.

Just for kicks, I've used my 8 - 10" sub drivers alongside a single pair of 8"ers in homebuilt BR boxes.  Believe it or not, I was able to integrate this massive sub array with the teensy mains.  This never would have worked without Complete Control.

As to the actual sound-producing boxes, I don't have a clue.  Mine are built-in and I haven't had a separate sub since an old M&K probably 5 years ago.

[Black Sand Cable]

You can also get very good results when it comes to EQ'ing with the SMS-1 from Velodyne.

A very nice "all in one" box that works very well indeed.

http://www.velodyne.com/products/product.aspx?ID=15&sid=625w802d

[miklorsmith]

That looks like a more tailored solution that's probably cheaper.  No doubt there's a LOT of stuff on the dbx I don't need.

[Carlman]

Thank you both! Great options.

[miklorsmith]

Hey, does that Velodyne do stereo?  It has numerous references to universal subwoofer (singular) compatibility.

[Brian Bunge]

Ummm....I don't think the Velo does stereo, but I could be wrong.

I'd really like to hear the Rythmik subs myself so I'm really hoping Carl goes that way.  Of course, I'm a little biased since I'd be making a profit off of him!  But we've worked together before so he at least knows my work.  Probably going to be a curved cabinet design as well! 

I have built a couple of Rythmik subs before but they used the 350W amp and LT circuit with various different drivers.  The best sounding was the one with Brian's older paper cone 12" woofer though.  That thing was awesome for a little 16" cube.

Anyway, luckily Carl won't need them until sometime around August.  I've got a couple of guys waiting on speakers from me so they come first.  This first pair of curved speakers has been a bit of trial and error but the next few pairs should go much faster.

I'm still shopping CNC machinists for my custom mid/tweeter faceplates so that's pushing things back a bit as well.  I just can't afford dropping $2K or so on faceplates unless I know I can move them fairly quickly.

[Carlman]

I liked your setup quite a bit, Doug... the simple method you used while I was there made sense but I don't remember the details.  I plan on doing 2 12" sealed and an xover. I will also be using  third sub for HT duty that'll b built into the seating platform. 

Thanks for dropping by with your adwice! and thanks to Mr. Wolf!     

TTYL,
Carl

[miklorsmith]

I agree with Doug - it may be counterintuitive but more driving space means lower excursions which translates to less distortion and an easier feel to all that bass.  My 8 - 10"ers don't sound like they're working at all to get flat 20 hz extension (it's actually about 4 db up at 20 hz).  They're sealed too, so no port business to deal with.  I like sealed alignments best as well, with EQ you can even dial in a simulated port hump if you like boom boom.