8x 18" LMS 5400 Ultras Sealed to 27 Cube 15hz Ported Build - Page 20 - AVS Forum | Home Theater Discussions And Reviews
Forum Jump: 
 71Likes
Reply
 
Thread Tools
post #571 of 614 Old 07-29-2016, 06:25 AM
AVS Forum Addicted Member
 
LTD02's Avatar
 
Join Date: Oct 2003
Posts: 21,157
Mentioned: 835 Post(s)
Tagged: 1 Thread(s)
Quoted: 2914 Post(s)
Liked: 3610
out of curiousity, i looked around for a power cable and couldn't find one. is 240v powercon really that uncommon in the u.s.?

Listen. It's All Good.
LTD02 is offline  
Sponsored Links
Advertisement
 
post #572 of 614 Old 07-29-2016, 07:51 AM
Advanced Member
 
gixerking's Avatar
 
Join Date: Jan 2012
Posts: 877
Mentioned: 17 Post(s)
Tagged: 0 Thread(s)
Quoted: 294 Post(s)
Liked: 472
Quote:
Originally Posted by notnyt View Post
Hm, what could these be for?

Nice! These, as in plural?
gixerking is offline  
post #573 of 614 Old 07-29-2016, 08:51 AM - Thread Starter
AVS Forum Addicted Member
 
notnyt's Avatar
 
Join Date: Dec 2008
Location: Long Island, NY
Posts: 10,193
Mentioned: 313 Post(s)
Tagged: 0 Thread(s)
Quoted: 3728 Post(s)
Liked: 3697
Quote:
Originally Posted by LTD02 View Post
out of curiousity, i looked around for a power cable and couldn't find one. is 240v powercon really that uncommon in the u.s.?
It's like speakons, you can just get the end and make your own.
notnyt is offline  
Sponsored Links
Advertisement
 
post #574 of 614 Old 07-29-2016, 08:52 AM - Thread Starter
AVS Forum Addicted Member
 
notnyt's Avatar
 
Join Date: Dec 2008
Location: Long Island, NY
Posts: 10,193
Mentioned: 313 Post(s)
Tagged: 0 Thread(s)
Quoted: 3728 Post(s)
Liked: 3697
Quote:
Originally Posted by gixerking View Post
Nice! These, as in plural?
yeah, for a pair of sp2-12000s

the joys of silence.
notnyt is offline  
post #575 of 614 Old 07-29-2016, 10:08 AM
Advanced Member
 
gixerking's Avatar
 
Join Date: Jan 2012
Posts: 877
Mentioned: 17 Post(s)
Tagged: 0 Thread(s)
Quoted: 294 Post(s)
Liked: 472
Quote:
Originally Posted by notnyt View Post
yeah, for a pair of sp2-12000s

the joys of silence.
Awesome man! Frees up amps for more subs! Lol
gixerking is offline  
post #576 of 614 Old 07-29-2016, 10:10 AM - Thread Starter
AVS Forum Addicted Member
 
notnyt's Avatar
 
Join Date: Dec 2008
Location: Long Island, NY
Posts: 10,193
Mentioned: 313 Post(s)
Tagged: 0 Thread(s)
Quoted: 3728 Post(s)
Liked: 3697
Quote:
Originally Posted by gixerking View Post
Awesome man! Frees up amps for more subs! Lol
rofl, selling the FP14000s. I don't have any more outlets to run them
notnyt is offline  
post #577 of 614 Old 07-29-2016, 02:15 PM
AVS Forum Addicted Member
 
LTD02's Avatar
 
Join Date: Oct 2003
Posts: 21,157
Mentioned: 835 Post(s)
Tagged: 1 Thread(s)
Quoted: 2914 Post(s)
Liked: 3610
Quote:
Originally Posted by notnyt View Post
It's like speakons, you can just get the end and make your own.

with speakons, there are countless companies that sell the cables. same thing with 15/20 amp powercon. i was just kind of surprised that when i looked around that i didn't see *any* 240/250v 30/32a powercon given that a 30 amp breaker must have a 30a receptacle according to the n.e.c. maybe i just wasn't using the right search terms or something.

Listen. It's All Good.
LTD02 is offline  
post #578 of 614 Old 07-29-2016, 02:19 PM - Thread Starter
AVS Forum Addicted Member
 
notnyt's Avatar
 
Join Date: Dec 2008
Location: Long Island, NY
Posts: 10,193
Mentioned: 313 Post(s)
Tagged: 0 Thread(s)
Quoted: 3728 Post(s)
Liked: 3697
Quote:
Originally Posted by LTD02 View Post
with speakons, there are countless companies that sell the cables. same thing with 15/20 amp powercon. i was just kind of surprised that when i looked around that i didn't see *any* 240/250v 30/32a powercon given that a 30 amp breaker must have a 30a receptacle according to the n.e.c. maybe i just wasn't using the right search terms or something.

search for powercon 32a
notnyt is offline  
post #579 of 614 Old 07-29-2016, 03:26 PM
AVS Forum Addicted Member
 
LTD02's Avatar
 
Join Date: Oct 2003
Posts: 21,157
Mentioned: 835 Post(s)
Tagged: 1 Thread(s)
Quoted: 2914 Post(s)
Liked: 3610
Quote:
Originally Posted by notnyt View Post
search for powercon 32a

yeah...not a single cable comes up anywhere.

Listen. It's All Good.
LTD02 is offline  
post #580 of 614 Old 07-29-2016, 03:27 PM - Thread Starter
AVS Forum Addicted Member
 
notnyt's Avatar
 
Join Date: Dec 2008
Location: Long Island, NY
Posts: 10,193
Mentioned: 313 Post(s)
Tagged: 0 Thread(s)
Quoted: 3728 Post(s)
Liked: 3697
Quote:
Originally Posted by LTD02 View Post
yeah...not a single cable comes up anywhere.
Oh, I see what you're saying. There just isn't as much demand for them and the plug types vary all over the place on the other end.
notnyt is offline  
post #581 of 614 Old 10-19-2016, 02:26 PM
AVS Forum Addicted Member
 
Archaea's Avatar
 
Join Date: Apr 2004
Location: Kansas City, MO
Posts: 11,042
Mentioned: 603 Post(s)
Tagged: 2 Thread(s)
Quoted: 3769 Post(s)
Liked: 3552

@notnyt - do you still have that big dip at 80hz today when you don't use smoothing? Have you tried to reverse the polarity on the subs or the speakers one or the other and measure again? That looks suspiciously a bit like something I had in my room when my mains were out of phase with the subs. When I had previously measured using 1/6 smoothing I couldn't see the problem, but when we used no smoothing it came to light quick. Luckily Desertdome discovered it while we were playing around.




Quote:
Originally Posted by Archaea View Post

One more thing. I'm embarrassed to say desertdome figured out after the meet when he was playing with his omnimic that while my eight subs were all in phase with each other --- they were out of phase with all the main speakers.

Here is a comparison of what we heard at the meet and what happened when the polarity was switched after the meet. Every speaker was in phase together, and the subs were in phase together --- just all the speakers were out of phase with all the subs --- meaning my crossover region between speakers and sub took a hit. I didn't ever consider that could be a problem, and didn't catch it when I'd measured and set things up. Audyssey didn't catch it either, on neither the Denon, or Onkyo. Worse yet, I've been using it like this the whole time I've had the sealed subs (I think), and didn't realize the issue. It was really easy to see when you use unsmoothed measurements, but I always pretty much use 1/6, which masks it to a larger degree. I learned I need to at least start with unsmoothed to more easily see something like that. Doh. Thanks DD!

Archaea's 9.8.4 Home Theater Room
(13) JBL CBT 70j-1 | Denon x7200wa | Sherbourn PA 7-350 amplifier | (8) Ultimax 18" sealed subwoofers | (4) iNuke DSP 6000 amplifiers | (4) MB Quart 12" subwoofers mounted direct mounted to Berkline theater chairs BOSS style | Epson 5040UB Projector | Jamestown 144" acoustic transparent 2.35:1 screen w/ Seymour XD fabric
Archaea is online now  
post #582 of 614 Old 10-19-2016, 02:27 PM - Thread Starter
AVS Forum Addicted Member
 
notnyt's Avatar
 
Join Date: Dec 2008
Location: Long Island, NY
Posts: 10,193
Mentioned: 313 Post(s)
Tagged: 0 Thread(s)
Quoted: 3728 Post(s)
Liked: 3697
Quote:
Originally Posted by Archaea View Post

@notnyt - do you still have that big dip at 80hz today when you don't use smoothing? Have you tried to reverse the polarity on the subs or the speakers one or the other and measure again? That looks suspiciously a bit like something I had in my room when my mains were out of phase with the subs. When I had previously measured using 1/6 smoothing I couldn't see the problem, but when we used no smoothing it came to light quick. Luckily Desertdome discovered it while we were playing around.
it's just a null in front of the lp where it's easier to measure. i often disconnect the fronts when taking measurements.
notnyt is offline  
post #583 of 614 Old 10-19-2016, 05:37 PM
AVS Forum Addicted Member
 
BassThatHz's Avatar
 
Join Date: Apr 2008
Location: Northern Okan range (NW Cascades region)
Posts: 10,632
Mentioned: 221 Post(s)
Tagged: 0 Thread(s)
Quoted: 3678 Post(s)
Liked: 4169
Quote:
Originally Posted by Stharlingny84 View Post
I went to Rob place the other day to demo his Home Cinema and it was an Extraordinary experience, The sound quality is just out of this world, the level of detail is unlike anything i ever heard, the dynamics are instant, the extension is incredible, the force and pressure of the midbass is tremendous, i mean i don't even have enough words to describe how PERFECT the sound quality was, it was like heaven on earth lol, Rob cinema is one of the most exquisite audio experiences anybody can have, his system can pleasure the most discriminating audiophile, and i been to some High end Room like for example Steinway Lyngdorf, the room was 130,000$ worth in equipment and don't get me wrong it sounded really good but if i have to pick i'll pick Rob system because is simply more superior, also i Demo the JBL M2 professional monitor speakers and i have to say the Rob Mains 4722 sounded superior to me, the imaging was right in the center and i felt the performers were right in front of me, the separation the instruments were excellent and the vocals of the performers were super natural.

But the best and my favorite part was the BASS (UNREAL), i have DUAL SVS PB-13 ultras and they are little toys next to his 8 LMS ultra 18 woofers, the best Demo was the incredible Hulk the last scene when hulk fell from the helicopter and hit the ground to fight abomination, the bass had the most greater definition and accuracy i ever heard in my entitled life, the bass was effortless and way beyond any subwoofer i ever heard at any price point, is funny how some People say the JL gotham (12,000$) is the best subwoofer ever lol, well is beautiful don't get me wrong but it can't touch Rob bass department.

If you want to get the best Home Cinema experiences in your life you have to get in contact with Rob and ask him for a demo, it is a must for any HT enthusiasm to experiences this level of Performance at least once in a lifetime, because i don't think you ever get this kind of Performance and especially BASS in anywhere else.

Well Done Rob and Congratulations.
I would say that is true of most DIY subs that are 18's or bigger.

But especially so for the LMS-18, FTW-21 and SI-24 drivers. By the time you bottom them out the cops are banging on the door with guns drawn. (and if not, add more... LOL)

Especially when you throw them into a Horn, where you gain 6-10db across the board and 12-16db near tuning (per cone...) as per modelling and data-bass charts:

When I converted 1 of my 4 sealed LMS-18's into a HzHorn it was just as loud as the remaining 3 subs and their connected amplifiers, COMBINED...

Horns also have very low amounts of chuffing because the mouth is so big, which helps keep THD lower than ported.

Going from sealed to ported you gain about 10-14db near tuning, and less then ~1db above 45hz. (Data-bass needs to measure more ported subs...)


The problem with 15-20hz horns is that they are big and hard to build... and they are totally useless above 80-120hz, unlike ported and sealed which remain musical to ~250hz. (There is no free lunch...)
Attached Thumbnails
Click image for larger version

Name:	7657.jpg
Views:	529
Size:	140.3 KB
ID:	1724817  
BassThatHz is offline  
post #584 of 614 Old 02-03-2017, 12:46 PM
Advanced Member
 
Jsin_N's Avatar
 
Join Date: Dec 2009
Posts: 756
Mentioned: 9 Post(s)
Tagged: 0 Thread(s)
Quoted: 442 Post(s)
Liked: 194
I don't see it listed. What is the width x height of one section of your ports? I see length of 55". I'm assuming this is centerline length?

Edit: Never mind. I see it in the pictures.

Last edited by Jsin_N; 02-03-2017 at 12:53 PM.
Jsin_N is offline  
post #585 of 614 Old 02-04-2017, 01:02 AM - Thread Starter
AVS Forum Addicted Member
 
notnyt's Avatar
 
Join Date: Dec 2008
Location: Long Island, NY
Posts: 10,193
Mentioned: 313 Post(s)
Tagged: 0 Thread(s)
Quoted: 3728 Post(s)
Liked: 3697
just took some impedance measurements...

Scott Simonian likes this.
notnyt is offline  
post #586 of 614 Old 02-22-2017, 04:35 PM - Thread Starter
AVS Forum Addicted Member
 
notnyt's Avatar
 
Join Date: Dec 2008
Location: Long Island, NY
Posts: 10,193
Mentioned: 313 Post(s)
Tagged: 0 Thread(s)
Quoted: 3728 Post(s)
Liked: 3697
I'm wondering if I wired the vc's in parallel and dropped the impedance, if it would be too low for the speaker power amps, or if they'd hit current limitations to make it not worth doing. Emailing Brian
notnyt is offline  
post #587 of 614 Old 02-22-2017, 04:38 PM
Bass Enabler
 
Scott Simonian's Avatar
 
Join Date: Oct 2001
Location: Clovis, CA
Posts: 21,509
Mentioned: 200 Post(s)
Tagged: 0 Thread(s)
Quoted: 5985 Post(s)
Liked: 5114
Quote:
Originally Posted by notnyt View Post
I'm wondering if I wired the vc's in parallel and dropped the impedance, if it would be too low for the speaker power amps, or if they'd hit current limitations to make it not worth doing. Emailing Brian
Have you been running each cab as 8ohm this whole time?
Scott Simonian is offline  
post #588 of 614 Old 02-22-2017, 04:39 PM - Thread Starter
AVS Forum Addicted Member
 
notnyt's Avatar
 
Join Date: Dec 2008
Location: Long Island, NY
Posts: 10,193
Mentioned: 313 Post(s)
Tagged: 0 Thread(s)
Quoted: 3728 Post(s)
Liked: 3697
Quote:
Originally Posted by Scott Simonian View Post
Have you been running each cab as 8ohm this whole time?
No, each cab is 3 ohms, see impedance graph above
notnyt is offline  
post #589 of 614 Old 02-22-2017, 04:42 PM
Bass Enabler
 
Scott Simonian's Avatar
 
Join Date: Oct 2001
Location: Clovis, CA
Posts: 21,509
Mentioned: 200 Post(s)
Tagged: 0 Thread(s)
Quoted: 5985 Post(s)
Liked: 5114
Quote:
Originally Posted by notnyt View Post
No, each cab is 3 ohms, see impedance graph above
Right.

Then I'd imagine half that might pose issues but I don't know for sure. Interested as well.
Scott Simonian is offline  
post #590 of 614 Old 02-22-2017, 04:49 PM - Thread Starter
AVS Forum Addicted Member
 
notnyt's Avatar
 
Join Date: Dec 2008
Location: Long Island, NY
Posts: 10,193
Mentioned: 313 Post(s)
Tagged: 0 Thread(s)
Quoted: 3728 Post(s)
Liked: 3697
Quote:
Originally Posted by Scott Simonian View Post
Right.

Then I'd imagine half that might pose issues but I don't know for sure. Interested as well.
I think it'd still be over 1 ohm. DCR would be about 0.5. DCR is currently about 2 ohms, but the enclosure adds 1. I'm not sure if I'd still see the same 1 ohm increase from the enclosure or if its relative to the DCR. Any idea on that?
notnyt is offline  
post #591 of 614 Old 02-22-2017, 05:10 PM
AVS Forum Special Member
 
michael hurd's Avatar
 
Join Date: Nov 2007
Posts: 3,406
Mentioned: 22 Post(s)
Tagged: 0 Thread(s)
Quoted: 634 Post(s)
Liked: 669
Rob, don't forget as the coils warm up the DCR increases.

If I am not mistaken Ricci did a few measurements of 'hot' impedance after sweeps, you might gain some insight there, not sure if it was on Data-Bass or here.

Ask your doctor if DIY is right for you. Side effects of DIY may include anxiety, elevated blood pressure, lightheadedness, rapid heartbeat, skeletal muscle flaccidity, euphoria, psychological dependence, insomnia, confusion, blurred vision, implusivity, uncontrolled or repeated movements.
michael hurd is offline  
post #592 of 614 Old 02-22-2017, 09:27 PM
Bass Enabler
 
Scott Simonian's Avatar
 
Join Date: Oct 2001
Location: Clovis, CA
Posts: 21,509
Mentioned: 200 Post(s)
Tagged: 0 Thread(s)
Quoted: 5985 Post(s)
Liked: 5114
Quote:
Originally Posted by notnyt View Post
I think it'd still be over 1 ohm. DCR would be about 0.5. DCR is currently about 2 ohms, but the enclosure adds 1. I'm not sure if I'd still see the same 1 ohm increase from the enclosure or if its relative to the DCR. Any idea on that?
Whatever you measure as impedance is what it is. Will you rewire and run an impedance graph with the new wiring?

Would be sick if the SP amp can handle that load.

Quote:
Originally Posted by michael hurd View Post
Rob, don't forget as the coils warm up the DCR increases.

If I am not mistaken Ricci did a few measurements of 'hot' impedance after sweeps, you might gain some insight there, not sure if it was on Data-Bass or here.
Josh has done a few systems with that test on DB. Can't think of any off the top of my head though.
Scott Simonian is offline  
post #593 of 614 Old 02-22-2017, 09:41 PM
Advanced Member
 
SeekingNirvana's Avatar
 
Join Date: Dec 2012
Location: Santa Cruz California
Posts: 992
Mentioned: 9 Post(s)
Tagged: 0 Thread(s)
Quoted: 258 Post(s)
Liked: 171
I'm mobile right now....can't link. But there is talk of dropping the sp amps to 1 ohm in one of beastaudio's threads. Search "Beasts first ever "Ballin' Out" NC g2g April 5th" starts around post 572. Not sure if it is relivent in your case since you are running ported and dgage was sealed, but might give some insight.
SeekingNirvana is offline  
post #594 of 614 Old 02-22-2017, 10:47 PM - Thread Starter
AVS Forum Addicted Member
 
notnyt's Avatar
 
Join Date: Dec 2008
Location: Long Island, NY
Posts: 10,193
Mentioned: 313 Post(s)
Tagged: 0 Thread(s)
Quoted: 3728 Post(s)
Liked: 3697
Quote:
Originally Posted by Scott Simonian View Post

Whatever you measure as impedance is what it is. Will you rewire and run an impedance graph with the new wiring?
Not unless I hear something positive back from Brian. It's a lot of work to vertically unknown an LMS driver that's been stuck to the enclosure for so long. I'll wait and see what he says. It's currently wired at 2 ohms DCR giving 3 ohms in the enclosure. It would be 0.5, I just don't know how the enclosure factors in, whether it's just adding impedance, or acting as a modifier. That's the difference between 0.75 ohms and 1.5 ohms. If it was 1.5 I'd just rewire it.
notnyt is offline  
post #595 of 614 Old 02-22-2017, 11:09 PM - Thread Starter
AVS Forum Addicted Member
 
notnyt's Avatar
 
Join Date: Dec 2008
Location: Long Island, NY
Posts: 10,193
Mentioned: 313 Post(s)
Tagged: 0 Thread(s)
Quoted: 3728 Post(s)
Liked: 3697
Doing some math, the SP amps can output 126v, that gives me 5300w at 3 ohms. I don't think there's much gain to be had here.
notnyt is offline  
post #596 of 614 Old 02-23-2017, 05:14 AM
AVS Forum Special Member
 
lukeamdman's Avatar
 
Join Date: May 2011
Location: Burnsville, MN
Posts: 3,789
Mentioned: 197 Post(s)
Tagged: 2 Thread(s)
Quoted: 1385 Post(s)
Liked: 2000
The impedance will be an average of all the frequencies being played at any given time (sorry for being captain obvious), so even though your impedance minimum is around 3ohm near port tune, how often those drivers will be strictly playing just those frequencies will be pretty rare.

Your system resonance between 20 and 40hz will really raise that average because 90%+ of movie "bass rumble" content and even dubstep is in that range.

With two of my drivers paralleled per channel, my DCR is about 1.4ohm. At times I wish it were closer to 1ohm just to get more juice out of the SP amps.

I know the IPALs with a DCR of 0.7ohm are no issue at all, but the amp is really only pushing hard down to ~25hz with those cabs which is a lot easier than 15hz.
lukeamdman is offline  
post #597 of 614 Old 02-23-2017, 02:17 PM - Thread Starter
AVS Forum Addicted Member
 
notnyt's Avatar
 
Join Date: Dec 2008
Location: Long Island, NY
Posts: 10,193
Mentioned: 313 Post(s)
Tagged: 0 Thread(s)
Quoted: 3728 Post(s)
Liked: 3697
Quote:
Originally Posted by lukeamdman View Post
The impedance will be an average of all the frequencies being played at any given time (sorry for being captain obvious), so even though your impedance minimum is around 3ohm near port tune, how often those drivers will be strictly playing just those frequencies will be pretty rare.

Your system resonance between 20 and 40hz will really raise that average because 90%+ of movie "bass rumble" content and even dubstep is in that range.

With two of my drivers paralleled per channel, my DCR is about 1.4ohm. At times I wish it were closer to 1ohm just to get more juice out of the SP amps.

I know the IPALs with a DCR of 0.7ohm are no issue at all, but the amp is really only pushing hard down to ~25hz with those cabs which is a lot easier than 15hz.
It's not the low end I needed more power on, it was the upper end, 50hz+. I was hitting the clip indicator a few times

Right now I'm hitting the voltage limitations, if I drop the impedance, I'll be running into current limitations. As per Brian, power transfer is optimum between 1.7 and 2.5 ohms on these amps. They recover quicker from hitting voltage limits than from hitting current limits. As I'd only gain around 1db rewiring, it's not worth it.

I'm contemplating building a small riser for my couch. Figuring out how to decouple it from the floor while at the same time have my actuators doing work is my current hang up. I'll think of something.
notnyt is offline  
post #598 of 614 Old 02-23-2017, 03:25 PM
Bass Enabler
 
Scott Simonian's Avatar
 
Join Date: Oct 2001
Location: Clovis, CA
Posts: 21,509
Mentioned: 200 Post(s)
Tagged: 0 Thread(s)
Quoted: 5985 Post(s)
Liked: 5114
Quote:
Originally Posted by notnyt View Post
It's not the low end I needed more power on, it was the upper end, 50hz+. I was hitting the clip indicator a few times

Right now I'm hitting the voltage limitations, if I drop the impedance, I'll be running into current limitations. As per Brian, power transfer is optimum between 1.7 and 2.5 ohms on these amps. They recover quicker from hitting voltage limits than from hitting current limits. As I'd only gain around 1db rewiring, it's not worth it.

I'm contemplating building a small riser for my couch. Figuring out how to decouple it from the floor while at the same time have my actuators doing work is my current hang up. I'll think of something.
My subriser is 'sort of' decoupled from the floor and I think it works great.

Technically, there are several layers. Concrete slab, carpet pad, carpet, carpet pad and then the riser.

Some form of damped spring/coil system for yours maybe? I think this would adversely affect the Crowson though. Hmm.


What you need is to graduate up from that whimpy "receiver power" stuff, bud. Give those mains the kind of voltage they really need.
Scott Simonian is offline  
post #599 of 614 Old 02-23-2017, 04:12 PM - Thread Starter
AVS Forum Addicted Member
 
notnyt's Avatar
 
Join Date: Dec 2008
Location: Long Island, NY
Posts: 10,193
Mentioned: 313 Post(s)
Tagged: 0 Thread(s)
Quoted: 3728 Post(s)
Liked: 3697
Quote:
Originally Posted by Scott Simonian View Post
My subriser is 'sort of' decoupled from the floor and I think it works great.

Technically, there are several layers. Concrete slab, carpet pad, carpet, carpet pad and then the riser.

Some form of damped spring/coil system for yours maybe? I think this would adversely affect the Crowson though. Hmm.


What you need is to graduate up from that whimpy "receiver power" stuff, bud. Give those mains the kind of voltage they really need.
*peeks behind speaker*

oh, what's this?



Why are there two connections?

let's see where they go....

A wild stack of hypex amps appears











6 Hypex NC400s for the front stage, fully active, RME Fireface UFX+ audio interface, using Brutefir for processing. I'm using autoformers for 12db padding and 100uf caps for protection on the HF sections



I documented a lot more of it in this thread:
https://www.avsforum.com/forum/155-di...e-journey.html
notnyt is offline  
post #600 of 614 Old 02-23-2017, 04:21 PM - Thread Starter
AVS Forum Addicted Member
 
notnyt's Avatar
 
Join Date: Dec 2008
Location: Long Island, NY
Posts: 10,193
Mentioned: 313 Post(s)
Tagged: 0 Thread(s)
Quoted: 3728 Post(s)
Liked: 3697
Quote:
Originally Posted by Scott Simonian View Post
My subriser is 'sort of' decoupled from the floor and I think it works great.

Technically, there are several layers. Concrete slab, carpet pad, carpet, carpet pad and then the riser.

Some form of damped spring/coil system for yours maybe? I think this would adversely affect the Crowson though. Hmm.


What you need is to graduate up from that whimpy "receiver power" stuff, bud. Give those mains the kind of voltage they really need.
Seriously though, that 5308 is beefcake. 240w or so into 4 ohms. It got the job done. It weighs like 70 lbs, big transformer in it. That said, I have a lot more flexibility now. At some point I'll put together a 4 channel amp for my surrounds and get whatever latest and greatest pre is out when I upgrade my projector.

Anyway, re: the riser... It's tricky to have something with enough support, but remain decoupled from the floor while having the crowsons effective and not being too large. I have some ideas, I'll likely start a thread with some of them sketched out later to get some feedback. I want to minimize the height and obtrusiveness, but want the effect to still be good. It's going to be tricky. I'm willing to test a few different designs as well.
notnyt is offline  
Sponsored Links
Advertisement
 
Reply DIY Speakers and Subs

Tags
Tc Sounds Lms Ultra 5400

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page


Forum Jump: 

Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off