System #45 (Monolith IIIx, SL3XC, Sequel II)

[karma]

HI,
WOW!!! WOW, what a nice system. I thought I was the master of complexity but I have much to learn from you. Very impressive. I'll bet it is a sonic champ too.

Question 1: I noticed that you decided to go with infinite baffles for your subs. Since the drivers will get no help from the enclosure, the free air resonance must define the low frequency limit of the drivers. I assume these have been carefully determined. Can you put your hands on the the low frequency limit data on the subs and post it?

Question 2: Since the Monoliths have good low bass response by themselves, do you limit the contribution of the sub? If so, what are the bandpass frequencies? I'm only guessing but I would bet the subs operate at infrasonic frequencies.

Thanks, Sparky

 

[JonFo]

HI,
WOW!!! WOW, what a nice system. I thought I was the master of complexity but I have much to learn from you. Very impressive. I'll bet it is a sonic champ too.

Question 1: I noticed that you decided to go with infinite baffles for your subs. Since the drivers will get no help from the enclosure, the free air resonance must define the low frequency limit of the drivers. I assume these have been carefully determined. Can you put your hands on the the low frequency limit data on the subs and post it?

Question 2: Since the Monoliths have good low bass response by themselves, do you limit the contribution of the sub? If so, what are the bandpass frequencies? I'm only guessing but I would bet the subs operate at infrasonic frequencies.

Thanks, Sparky

Sparky, thanks. It is indeed at the outer edge of complexity. My goal for the future is to start reversing that trend.

To your question #1, the IB concept is that you remove the enclosure entirely from the equation. By segregating front and rear waves into equal loads, we can maintain a more linear excursion pattern (no log compression at max excursion). However, max excursion is what ultimately limits an IB driver, which is why one picks models that have huge xMax (23mm in the case of mine).

The FS(hz) of the AV15 is 22.3 Hz, but will play below that with no problem (see the FAQ link for more).
My measurement rig is not accurate below 20hz or so, but I’m flat to 20hz.

Using the Thigpen rotary woofer test disc, I’m definitely moving tons of air (and the room) at 15hz, but at 5hz, while the cones are moving substantially, the coupling of cones and the air breaks down and while there is some sensation, it’s not what one would get with the Rotary. BTW- A rotary is in my future; as soon as they drop under $5K that is

Each of these AV15 drivers displaces 3.82 liters (p-p) so four of them gives 15.3 liters of displacement. Considering most commercial 18” subs only do 2 to 3 liters, you can see how not only will this one go deep, it can go very loud while at the same time maintaining very, very low distortion.


The FAQ for IB’s:
http://home.comcast.net/~infinitelybaffled/

Here is the Frequency response of my SL3XC Center + Sub, pretty darn good for an in-room at 5meters. Note that it’s flat down to under 20Hz. (this is both pre and post room treatments).

On to your Question #2. The ranges that the Monolith woofers run at is 81Hz to 315Hz (using the new woofers designed for higher freq.). Sub runs at 80Hz and below (using 24db / Octave slopes).
But a picture speaks 1K words; here is a shot of the DR260 crossover settings:

 

[JonFo]

Updates to personal web site

Just to let you know I totally re-did the (lame) web site with new tools and a new look. Now looks a little better.
Feedback welcome.

I still need to add a nav tree on the left for all the sub-levels in the Home theater section.

I also still need to add more recent pics. But digital camera just busted due to exploding batteries (yuck, what a mess), so new one arriving this weekend

Pic updates should happen Monday the 22nd.

Here's the link: http://www.jonathanfoulkes.com/Home_Theater/HomeTheater.htm

 

[STV]

Very sweet setup John Those towering Monoliths are awesome! Wow, you have a lot of impressive audio/video gear. Very nice!

 

[JonFo]

Finally got new camera, so here is a 3 Qtr shot of the rear of the room as seen from the right front Monolith:

 

[JonFo]

And a view straight back from in front of the projector:
You can see the acoustic treatments on the rear wall. That's RPG skyline straight ahead and Auralex 2D diffusers behind the Sequels.

 

[JonFo]

A full frontal shot. It's so hard to get a decent picture in this bat-cave. So some of the luma is blown out a bit, but you can see the business end of the theater:

 

[JonFo]

^^

PS- that SL3 there on the right is the 'left over' from my center channel project. Makes a very nice light stand now :haha1:

 

[Pcar928fan]

Jonathan,

VERY NICE DUDE! Man we are just having ML theaters showing up all over the place now! LOVE IT!

 

[ScottG]

^^

PS- that SL3 there on the right is the 'left over' from my center channel project. Makes a very nice light stand now :haha1:

Ok, that's both sad and funny at the same time

 

[JonFo]

The real shame is that my pride and joy is not even visible. But boy, can it be felt and heard. Loud and very, very clear.

 

[wink]

JonFo,
That center channel is phenominal! I would give anything to hear it....well....almost anything

Dan

 

[JonFo]

JonFo,
That center channel is phenominal! I would give anything to hear it....well....almost anything

Dan

Hey, all it takes is to ask nicely and show up, and anyone can hear it.

Seriously, anyone on the club here in the southeast (or traveling through Atlanta and able to take a weekend afternoon out, can drop by).

I'd love to share it with others who love ESL speakers.

 

[wink]

Thanks for the welcome invite!:rocker: When I lived in Ohio I would have taken you up on it, but since I moved out west it would be a thousand times more difficult. Hey maybe Gayle will get to see your center channel on here and make a production model for us all to enjoy.......for that special price of course

Dan

 

[wink]

Do you happen to have a pic of your equipment rack? Or did I just overlook it on this thread somewhere?

 

[JonFo]

Equipment Rack pic 1

Here is one (fuzzy) pic. I just got the new camera and tried some shots, but they didn't come out well. I need to bring in some lights and maybe even move the Monolith to get a good shot.
Also, the bi-fold door covers a few inches of the left side stack (mostly amps), so I'd have to remove that as well for a good shot. Might do it next weekend and update these two posts.

The rack is a Salamander Designs Synergy Twin 40 + a Twin 30 stacked on top with some extra shelves added as well (to handle the large number of smaller boxes I have).
These are great racks, fully adjustable shelves and open on all sides and super strong. Worth their (high) price.
The rack is in an adjacent equipment room, normally behind the bi-fold door. There are IR repeaters and automation control through touchscreens in the HT to manage this stuff remotely.

This is the bottom half of the rack, on the left (from Bottom to top):
Buttkicker amp
Alesis MV4 delay
Sunfire Stereo
Sunfire Cinema Grand Signature
Sunfire Cinema Grand
Stack of DVD-A/SACD's in front of Niles power sequencer

The Right side (again, bottom up)
Pioneer CLD-97 Laser disc player (It's massive and It's beautiful, but so hidden down there in the dark)
Sony TAE-P9000ES Multichannel switcher / pre-amp
DBX DriveRack 260 speaker processor for Monoliths
DBX DriveRack 260 speaker processor for SL3XC Center
Behringer DCX2496 speaker processor for Sequels
Behringer MX882 Mixer for Sub signals
Behringer MX882 - in gain control multi-mono mode for adjusting levels to processors or amps
Behringer BFD1124 20 band parametric EQ for Sub and Buttkicker (each uses its own channel)
Meridian 568 pre-processor
Meridian 518 processor
Philips DVD/SACD carousel player (for PAL discs)
Bottom of Denon DVD2900 universal player

 

[JonFo]

Equipment Rack pic 2

And here is the top half.

So from top down this time:

Left side:
Sony SAT-T60 DirecTiVo DVR
Crown XLS602 1,200W amp for IB Sub
Stacks of HD DVD’s on top of
Toshiba HD-A1 DVD player
(repeat from Pic 1 list with stacks of DVD-A’s)

Right side (again, top down this time):

DirectTV HR20-700 High Def DVR
Sony PS2 (and a couple of Rally games) sitting on
Hughes HR10-250 DirecTV HD DVR
Gooseneck LED lamp clamped to shelf
JVC S700 7 input S-Video/Audio switcher
RCA S-VHS deck
Denon 2900 universal player
(repeat from pic 1 list)

 

[Kruppy]

Jonfo,
Egads, I can't imagine what your cabling looks like with all that equipment.

 

[Pcar928fan]

DAMN! And I thought I had a lot of gear...no comparison! WOW! Looking good!

 

[wink]

Thanks for the pics JonFo! Just as I thought, an awesome display of electronics hidden in the closet. My wife and I have decided to put our pro audio rack flush mounted in the wall next to the right surround. This of course is going to require redesigning the front of the house a bit. I was going to buy a single 73" pull out rotating rack for the eight pieces of equipment, but have since decided on a side-by-side unit. After seing your rack of stuff I'm glad we've decided to allow for future expansion.


Thanks again for the pics!:cheers:

Dan