Dspeaker Dual Core review

rodge827 · « **Reply #40 on:** 24 Oct 2012, 10:14 pm »

Full spectrum room measurement with calibration to 450hz on(red) and off(black).

DaveC113 · « **Reply #41 on:** 24 Oct 2012, 10:17 pm »

rodge, you could output those graphs to your computer, apply a bit of smoothing, then save the screen image as a .jpg and post it up...

Rclark · « **Reply #42 on:** 24 Oct 2012, 10:50 pm »

And that's two subs right or just one? What type?

rodge827 · « **Reply #43 on:** 24 Oct 2012, 10:52 pm »

Don't know how to do that yet.

Will learn how for the future.

2 Subs...Shelby + Kroll...10" Bandpass design

I have been on the phone with Tim Ryan all afternoon doing measurements and making adjustments with the Dual Core.
Most of these pics have been put up so that y'all can see what the thing does.

What we're working on now is trying to get rid of or soften that sharp dip around the 40-60hz area.

Stay tuned...

Rclark · « **Reply #44 on:** 24 Oct 2012, 11:10 pm »

From what I understand that null is ubiquitous in small rooms and about impossible to get rid of without more subs.

Rclark · « **Reply #45 on:** 24 Oct 2012, 11:20 pm »

In the review of it though, it says the device greatly reduces the decay at that null so you really dont notice it anyway.

It will be interesting to find out if dual Legends acts like 4 subs.

rodge827 · « **Reply #46 on:** 24 Oct 2012, 11:49 pm »

OK,

I moved the subs into the corners of the room and did a 500hz calibration in normal mode and this is what I got:

As you can see the dip has gotten a little smaller and a little less sharp.

rodge827 · « **Reply #47 on:** 25 Oct 2012, 01:56 am »

Turned up the volume a little more...

Room measurement to 500hz

Calibrated to 500hz

Note that the hole is getting smaller.

Rclark · « **Reply #48 on:** 25 Oct 2012, 02:46 am »

That's very impressive Rodge. Wow! Get's me all hopped up seeing that stuff.

Just paid for my Ncores this week, that thing's next!

I am willing to bet... if you added another sub or two... nullbegone. Thought about it? You could have very very flat response provided you treat your HF reflection points.

rodge827 · « **Reply #49 on:** 25 Oct 2012, 03:10 am »

Rclark,

My first reflection points are treated, but I might do it on a larger scale. Currently the side wall treatments are 2'w x 3'h as well as the ceiling. I'm looking into making those a little bigger say 3'x3' for the side walls and 6'x6' for the ceiling. The dip is from the floor bounce and now is hardly audible. It's getting late here and I'll be working over the next 2 days, so I'll mess around a little more over the weekend. As DaveC113 mentioned there is room for a little smoothing. That will all come later.
There is a learning curve to using the Dual Core and Tim Ryan at Simplifi Audio has been a big help in showing me how some of the different features work. He really knows his stuff and has helped me to dial in the bass. If you notice from the last graph, the bass is pretty flat up to 120hz. Those dips repeat themselves every 60hz or so. Apparently this is normal? Dunno...trusting Tim on that one.

Rclark · « **Reply #50 on:** 25 Oct 2012, 04:07 am »

In a rather lengthy Epic Legend thread (the sub I own), I saw a measurement graph from an owner who had a single, and that null was there, added another, null practically vanished, in that room. Now, the Legend has dual opposed drivers, so I'm hoping that two of them plus the Dual Core will get me where I want to go.

It is a gorgeous sub, keeps up with my framed maggies (no small feat), although with Ncores it will be different, I will be dropping the crossover down a lot..

In fact I want to use the Dual Core as a crossover, and see if I can, over time, totally maximize a pair of them for my room. This is going to be so much fun, and I suspect I will learn quite a lot.

medium jim · « **Reply #51 on:** 25 Oct 2012, 05:31 am »

There is no question that a pair of subs soothes out room funkiness better than one. There are nice links in the stickied helpful link thread that covers this, as well as, a thread or two that discusses the merits of multiple subs.

Jim

rodge827 · « **Reply #52 on:** 25 Oct 2012, 11:41 am »

Quote from: Rclark on 25 Oct 2012, 04:07 am

In a rather lengthy Epic Legend thread (the sub I own), I saw a measurement graph from an owner who had a single, and that null was there, added another, null practically vanished, in that room. Now, the Legend has dual opposed drivers, so I'm hoping that two of them plus the Dual Core will get me where I want to go.

In fact I want to use the Dual Core as a crossover, and see if I can, over time, totally maximize a pair of them for my room. This is going to be so much fun, and I suspect I will learn quite a lot.

When I purchased my speaker system Tim Kroll (Shelby + Kroll) suggested 2 subs to pressurize my 15w x 21l x 8.25h room properly.
The subs are a 10" bandpass design and are geared to the music lover, not so much for HT. I dialed them in as best I could with the less bass is best theory, not wanting to hear or feel the sub and not know that it is in the room. I placed the subs very close to and behind the speaker stands, almost touching them in the middle of the room, using the Cardas formula.

I first used the Dspeaker 8033s and the overall sound greatly improved. Bringing in the Dual Core helped things along even further. From the measurements Tim Ryan had me move the subs into the front corners of the room and turn up the volume considerably. I originally had the volume pots at 9:00 and they are now at 2:00. As you can see from the graphs the "hole" from 35hz-60hz has close up rather nicely and the bass does sound much better in the room. I'm not done yet, as mentioned above I will play around with the bass output a little more over the weekend. Tim said to me that my original measurement was rare since most people have the bass turned up way to high. In my case we were working from the other direction, mine was way to low.

Doing all of this tweeking and measuring does take some time. You need a near silent room to do the measurements,about 2 mins each. Then run a calibration about 12 mins at 500hz. Moving my subs to the corners was a timely project since there was some shelving that needed to be removed.

Damn, the things we'll do to gain that little bit of sonic harmony!

Crazy whacked audiophile perfectionists!

Spending hours of time on a beautiful day to prepare for when the weather turn sour?

Heck I coulda' ben workin' on my putting!

Rclark,

How are you thinking about implementing the Dual Core crossover?

Rclark · « **Reply #53 on:** 25 Oct 2012, 05:59 pm »

As of now my plan is to get Gik qrd diffusers behind my Maggie's, build some corner traps with quartered rockwool and fabric, get some Gik Gridfusiors for above my listening position (I think), buy a second Epik Legend, place both as best as possible using the Dual Core's measurements, and then finally run the calibration, full calibration to 500hz. I believe the diffusors will handle issues from there. I hypothesize that a pair of Legends will end up very flat. I then want to save that setting, connect the subs via lfe, and begin experimenting with different crossovers for them in this room.

I may also see if I can't put a wedge of quartered rockwool along that line between the corners. Just tape it up, and then another along the floor.

Rclark · « **Reply #54 on:** 25 Oct 2012, 06:56 pm »

Damn I might just do the above with this in the center
http://www.srlacoustics.com/8-ft-wide-bare-diffuser/

Gotta love this forum.

sts9fan · « **Reply #55 on:** 25 Oct 2012, 07:38 pm »

How is this better then a miniDSP with REW EQ and biquads?
Plus it's over four times the price. I have done before and "after " measurements with the old antimode and was underwhelmed.

Rclark · « **Reply #56 on:** 25 Oct 2012, 08:06 pm »

I wouldn't say 4 times, more like near twice the amount when you figure in a microphone and all the cables you need. Soundcard too.

This is both automated and manual control, so you can be a beginner like myself and be good to go out the gates, and then take it from there with the more advanced settings.

Plus the correction is reported to be more advanced than the 8088. And proof is in the pudding, all the graphs and waterfalls I've seen look very impressive.

On top of that it is a battery powered dac and preamp, with remote, and there's even a screen display on the front.

Not seeing a whole lot of downside for $1100.

roscoeiii · « **Reply #57 on:** 25 Oct 2012, 08:08 pm »

And there are full range options like manual digital EQ and channel balance that I am not sure that the sub-only versions had...

rodge827 · « **Reply #58 on:** 25 Oct 2012, 09:30 pm »

Quote from: Rclark on 25 Oct 2012, 08:06 pm

On top of that it is a battery powered dac and preamp, with remote, and there's even a screen display on the front.

The Dual core comes with a wall wort power supply and can be run in 12v DC.

Either way the thing sounds very good, but has more of a natural sounding quality (less hard) on a good 12v battery PS.

rodge827 · « **Reply #59 on:** 25 Oct 2012, 09:40 pm »

Quote from: sts9fan on 25 Oct 2012, 07:38 pm

I have done before and "after " measurements with the old antimode and was underwhelmed.

The algorithm used in the Dual Core is waaay improved over the 8033c and 8033s which I had owned.

The Dual Core will put your speakers in proper phase and adjust the crossover frequency automatically. ie: My sub is set to 100hz as the cross over point for my monitors. To me it looks like it is correct, but if I'm off by a couple of hz the Dual Core will compensate and bring the frequency into balance. As long as the frequency being corrected (calibrated) is above 100hz.

Pretty cool huh?