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Mjölnir Subwoofers - Page 3

post #61 of 121
Your electrician is thinking about much crazier power demands that what you will actually be pulling with the 2 amps. Hence the word "appliances". Guaranteed he has no clue what type of power these amps will draw. Crown probably has a chart showing the current draw and consumption at 1/6th and 1/3rd power. Even 1/6th power is far more continuous draw than you will likely ever see in practice.

Look at how prosound outfits who these amps are designed for distribute their power to these amps.

2 of these on a single 240v 20 or 30amp line will be fine. These are not continuous drawing appliance type devices.
post #62 of 121
Thread Starter 
just got off the phone with Crown.....basically I will have to wire (2) single receptacle outlets in parallel to a terminal strip which is then connected to the 240 line. This will meet code as one cannot "loop" outlets togther like you would with a 120 line.

Little of topic....when splitting the subwoofer signal going from Onkyo 876 receiver to amp 1 and amp 2 does the signal strenght drop if one uses a y splitter?
post #63 of 121
Quote:
Originally Posted by bodhisafa View Post

just got off the phone with Crown.....basically I will have to wire (2) single receptacle outlets in parallel to a terminal strip which is then connected to the 240 line. This will meet code as one cannot "loop" outlets togther like you would with a 120 line.
Little of topic....when splitting the subwoofer signal going from Onkyo 876 receiver to amp 1 and amp 2 does the signal strenght drop if one uses a y splitter?

Here is the amp draw of an iTech 8000 @ dual 1-ohm @ -10db full excursion @ 16hz.

Looks like 7-10 amps @ 240v/60hz.

Using a y-splitter will make it sound worse; the iTech's can be daisy-chained with XLR, do that instead.

You can loop 240v, the physics supports it, one 30amp wire in parallel is the same as two direct 15amp wires; a total of 30amps is drawn from the 2-pole service in both instances, but perhaps it's just not to "official electrical-code" wink.gif

Another thing you should be aware of is that unless you flip the blue breaker at the back of the amp to the OFF position (or equivalent), the amps are still technically ON and will draw 15kW/hrs per day (yes, even when turned OFF from the front panel). I learned that the hard way... you can save yourself from the increased electrical bill.

When turned on and idling, but not actually outputting any music, it will draw 34,000watts of power per 24 hours. They are like mini space heaters in that mode.
and heaven forbid if you actually left it playing loud music for 24 hours, then it would be closer to 100,000 watts per 24 hours.

They are not very "green" amps, consider yourself warned.
Edited by BassThatHz - 11/13/12 at 12:37am
post #64 of 121
Thread Starter 
I downloaded the HiQnet System Architect version 3.3 and Iam playing with it the software to get familiar. The number 3 preset has been loaded unto amp one just waiting on the electrician to show up and then I can test the two LMS Ultras for fact. defects. Hopefully none are present.


Just to make sure when hooking up the Onkyo876 to the two amplifiers the chain goes: receiver sub pre out (rca )> Ch1 input (XLR male) >amp 1 is on Y input mode> Link out of ch.1 (XLR female)...... now going into amp 2....Ch. 1 input (XLR male). Amp2 is in Y input mode as well.
Edited by bodhisafa - 11/19/12 at 5:48pm
post #65 of 121
Thread Starter 
Just to make sure when hooking up the Onkyo876 to the two amplifiers the chain goes: receiver sub pre out (rca )> Ch1 input (XLR male) >amp 1 is on Y input mode> Link out of ch.1 (XLR female)........................... now going into amp 2.......................Ch. 1 input (XLR male). Amp2 is in Y input mode as well.

backpanel.jpg
Edited by bodhisafa - 11/20/12 at 4:56am
post #66 of 121
That wiring is correct, but you'll want to have both amps be in Y-input mode.

You want the input signal to be hovering around an average of -10db or so.

Now depending on the output voltage of your Onkyo, you may have to play with the input gain and EQ input gain and the Onkyo's output signal strength to achieve this. I was feeding mine with a Behringer EQ and a Emotive UMC-1; obvisously your equipment will be vastly different.

Just make sure to turn the output volume to roughly -90db (near mute or disconnect the sub wires); and then starting at a very low input volume, work up from there until the input signal is hoving around -10db (or there abouts). Once you have that dialed in (at this point you'll want your main-speakers running), you can increase the output level and enjoy the extra bassy music. (I wouldn't recommend ever going much above -10db on either the input or output signal).

If your feeling "extra-adventurous", you can attempt to disable the High Pass filter (and starting at a low volume)... actually, I wouldn't recommend this unless you really know what you are doing.

post #67 of 121
Thread Starter 
email from Onkyo with relation to the pre out on the onkyo receivers.

Pre-out level at Recievers

Balanced: 1V/235 Ohm, Max output: 11.0 Vrms
Unbalanced: 1V/470 Ohm, Max output: 5.5 Vrms


Mine has an RCA so Iam looking at 5.5Vrms for my receiver.

So to start I should have the receivers volume, sub trim level (in receiver) and amp gains set as low as possbile, without the subs connected.

I then turn the volume of receiver, sub trim level and amp gain up slowly until "input/otput signal is hovering around -10db"

ounce thats done I can turn the volume of the receiver as loud as I wanted and be safe or is there a limit?

During the initial setup, how high should I have the receivers volume in order to "tickle" the -10db mark?
Edited by bodhisafa - 11/20/12 at 7:04pm
post #68 of 121
The goal is to have all the electronic devices reach their maximum level at the same time; not that you would ever run it at maximum however, but rather just be equally-levelled to that.
Basically you want to avoid having one device idling along while all the others are clipping; or any combination thereof.

Easier said than done, specially when mixing pro-gear with home-gear.
post #69 of 121
Thread Starter 
Did some lite testing over the weekend on both drivers to check for manufacturer defects, I could not hear anything that would cause concern. When placed on a pillow the driver would vibrate and make some noise but when picked up by the mounting points it got rid of the "noise". Is this normal, the floo is a suspended floor above a garage.

I have aquestion about the sensitivity (gain) settings on the amp. Looking at the screen capture above the amp is set exactly as shown. If I want the gain to be "hotter" should the input gain (db) be higher in number or lower?????
post #70 of 121
That is normal.

Your Onkyo is set to maximum sub out? Lower voltage is greater sensitivity.

If that doesn't work, increase the bandpass gain. Failing that increase the Input EQ gain.
post #71 of 121
Thread Starter 
No, the subwoofer pre out or trim level is set to +5 at the moment. What is yours set too?

This is my first time doing this, was wondering if the woofer will sound louder ounce in the box?
Edited by bodhisafa - 11/27/12 at 10:33am
post #72 of 121
Here is the LMS at the point where it begins to overheat after 4 minutes. At a few feet away the mic is being subjected to SPL in the 120-130db range (per sub).


With all 4 of yours going it should be loud enough to break some door hinges. biggrin.gif


I don't use a receiver and I don't use a LFE/sub-out channel.
My system is completely different than yours so it won't translate at all really, but... I run mine as a 2-ch hardwire and have the knob set to 70db out of 80db, my Behringer floats between -6 and -20db, and the iTech about the same. Which drives the Behringer EQ and iTech to it's fullest capabilities.
post #73 of 121
Thread Starter 
All right I will keep working on it and get it dialed in.

1) As far as boosting the low end of my sealed setup what device should I purchase?

2) Protection of drivers what should I purchase and implement in the system, and how do I bypass the filters in the Itech?
post #74 of 121
1) Boost it, why? The itech has 48db of gain at 2volts, that's more than enough to boost any signal from any decent device.

2) Why, are they giving you problems? Mine is flat to single digits with the high pass disabled. Even with this preset of 28hz (i.e -12db @ 14hz), it still goes down to 20-25hz @ -4db

Question: What input level are you getting with the sub-out set to max, on loud action movies?
post #75 of 121
Thread Starter 
What I mean is boosting the low end in the system. I read that is what people do with sealed system. I was not referring to boosting the receiver signal. And the high pass is to protect the driver from bottoming out and denting the cone.

Basically if I run the amps with your preset I'm all setup.
post #76 of 121
Quote:
Originally Posted by bodhisafa View Post

Basically if I run the amps with your preset I'm all setup.

We are waiting for your review, so how does it sound? The best ever? Better than before? Meh? wink.gif
BTW, What were you upgrading from?

Have any pictures, videos or measurements of it working? We all want to see those four LMS's pumping in unison.
post #77 of 121
Thread Starter 
Sorry about the delay, I have been working none stop (even weekends) for the past month and haven't had a lot of time to devote to the project. It's close though. I need to paint and stuff the cabs. Also I'm working on a DYI AV cabinet, that's needs to go in a wall hopefully today after work.

Electrician hasn't showed up still, so everything is on wait at the moment. I need to hack the plugs of the amplifiers and install 240 volt, I believe they will be NEMA 6-20. Instead of what's on there at the moment.

I hoping all this will payoff in the end, my only reference point will be a single JTR Orbit Shifter which I owned for about 8 months. So hopefully 4 LMS ultras will be and upgrade.

By the way if anyone is looking to sell their LMS Ultras I'm looking for two
post #78 of 121
Thread Starter 
I need to source good 10 or 12 gauge wire as well as good quality binding posts.
post #79 of 121
Quote:
Originally Posted by bodhisafa View Post

I need to source good 10 or 12 gauge wire as well as good quality binding posts.

Personally I like these binding posts: http://www.soniccraft.com/products/connections/bindingpost/vampire_bp15hex.htm I have never had one strip and you can tighten them down with this: http://www.musicdirect.com/p-227-audioquest-binding-post-wrench-bpw.aspx

For wire Monoprice carries a decent 12 awg and bluejeans cable has the Belden 12 and 10 awg wire which is good as well.
post #80 of 121
Those vampire binding posts used to be a lot cheaper so maybe you can google them for a better price. I bought a bunch of them when they were about half the price they are listed for now.
post #81 of 121
Quote:
Originally Posted by bodhisafa View Post

I need to source good 10 or 12 gauge wire as well as good quality binding posts.

May have missed something, but why not speakONs as mentioned earlier? I personally love speakONs and a cable like Canare 4s11 (11ga. when paralleled). Super-clean install, especially with 90deg connectors, no muss, no fuss. And a lot cheaper/easier/cleaner/reliable than boutique binding posts and bananas. There's probably good reason pros use them almost ubiquitously.
post #82 of 121
Thread Starter 
I've had some "time" off the past few days (been sick) but I haven't been able to work on the cabs to be able to finish them, all that is needed is paint. Like a few members lately I have contemplated changing my original idea of 4 LMS Ultras vs 8 SI's. But it would seem that my space is rather limited.

I could squeeze in (2) cabs per side but that would mean having two woofers directly behind L R channels(could these be bad for the sound) as well as having to push the L and R channels forward some.

The mess on the floor will be cleaned up after I install my in wall av cabinet...sorry for the mess.

What do you gents suggest.




post #83 of 121
Unless you have a HUGE room then I would rather have 4 LMS Ultra than 8 SI 18's or Dayton HO 18's.

I used to have a pair of LMS Ultra's and now have a multiple sub system which includes (4) Dayton HO 18's, (8) 12" sealed and (8) 10" sealed and soon another 4 SI 18's. I can shake my room and house better than my buddy with quad LMS Ultra's but I have to admit that his setup sounds cleaner.

If I was you I would finish up the LMS Ultra build and later on add another 2 or 4 SI or Dayton 18's in another part of the room if you think it's needed. Doesn't look like you have a huge room though so I would be surprised if you are not impressed unless your sitting in a null.
post #84 of 121
Quote:
Originally Posted by mjaudio View Post

I can shake my room and house better than my buddy with quad LMS Ultra's but I have to admit that his setup sounds cleaner.
Yeah no kidding man!! Youre room is the definition of TACTILE FEEL!!!! biggrin.gif
post #85 of 121
Hold on a minute here!!! Something isn't right... Where are your Ultras? Where are the iTech's? I thought you were basically done? eek.gif
This looks like an old pic.

That room is barely large enough to house or contain the output of quad Ultras.
I'm getting somewhere between 110db to 114db with just 1/4th of your rig in a 4000cubic foot room.

I could understand that you may not be "accustomed" to hearing the lack of distortion eminating from the subs, the inverse of which contributes a large degree in the perception of "loudness".

Do you have an SPL meter? Audessy? Have you taken any measurements yet, with say... REW?
What was the output level according to the iTech's? Did the Ultra's appear stressed out or something?

You will not gain many db's more, unless you go with quad RE-18's in a IB, at max excursion. Or a line-array of JBL horns with a gigawatt eek.gif
You are already basically using the best subs money can buy. So that's all the SPL you're going to get.
Something doesn't add up here. Bad room-acoustics?
post #86 of 121
Thread Starter 
Quote:
Originally Posted by mjaudio View Post

Unless you have a HUGE room then I would rather have 4 LMS Ultra than 8 SI 18's or Dayton HO 18's.
I used to have a pair of LMS Ultra's and now have a multiple sub system which includes (4) Dayton HO 18's, (8) 12" sealed and (8) 10" sealed and soon another 4 SI 18's. I can shake my room and house better than my buddy with quad LMS Ultra's but I have to admit that his setup sounds cleaner.
If I was you I would finish up the LMS Ultra build and later on add another 2 or 4 SI or Dayton 18's in another part of the room if you think it's needed. Doesn't look like you have a huge room though so I would be surprised if you are not impressed unless your sitting in a null.

You are correct, its not a big room at all. Just trying to pack as much punch in there as possible.
Quote:
Originally Posted by BassThatHz View Post

Hold on a minute here!!! Something isn't right... Where are your Ultras? Where are the iTech's? I thought you were basically done? eek.gif
This looks like an old pic.
That room is barely large enough to house or contain the output of quad Ultras.
I'm getting somewhere between 110db to 114db with just 1/4th of your rig in a 4000cubic foot room.
I could understand that you may not be "accustomed" to hearing the lack of distortion eminating from the subs, the inverse of which contributes a large degree in the perception of "loudness".
Do you have an SPL meter? Audessy? Have you taken any measurements yet, with say... REW?
What was the output level according to the iTech's? Did the Ultra's appear stressed out or something?
You will not gain many db's more, unless you go with quad RE-18's in a IB, at max excursion. Or a line-array of JBL horns with a gigawatt eek.gif
You are already basically using the best subs money can buy. So that's all the SPL you're going to get.
Something doesn't add up here. Bad room-acoustics?

Slow down BassThatHz,

The Itechs are in the room and so are the Ultras (minus 2), just cant see them in the crappy iphone shot I took. It just has not been setup yet, cold weather + a cold + tools/materials shortage = not done yet. Its coming.
post #87 of 121
Quote:
Originally Posted by bodhisafa View Post

Like a few members lately I have contemplated changing my original idea of 4 LMS Ultras vs 8 SI's. But it would seem that my space is rather limited.
What do you gents suggest.

Ah I see now... so you were just getting cold feet; and were theorizing that you'd want even more output after you were done. wink.gif
In that case, just install as many subs as will fit in the room, like Dayton Pro 18's or RE-18's in an IB. But you might want to wait until your are done the first phase, as these four alone should age your house structurally by 10 years or so. tongue.gif
post #88 of 121
Thread Starter 
After many delays I finally have the four Ultras playing some bass. I used the presets that BassthatHz sent me, loaded them to the Itech 8000's and hit play. Considering his electronic system chain is different than mine the only change I have made is to change the input sensitivity of the Itechs. I had to turn the SW preout setting to +10 and the itech input sensitivity as high as it would go to get the calibration to be at 75Dbs.

Initial impression is underwhelming bass. I know theres is much tweaking involved, just not sure how to adjust the itechs for more performance to suit my taste and room.

I do have the mini dsp mic, so REW measurements need to be taken tonight, I need HELP on how to do this.

My equipment chain:

DirecTV hd box > Onkyo 876 > Itech8000 theres also an OPPO blu ray player in the mix
post #89 of 121
Why are you using BthatHz's preset's, if I may ask? Nevermind. Read up on it.

Awesome quad Ultra's though. smile.gif
Edited by Scott Simonian - 3/12/14 at 9:42am
post #90 of 121
Thread Starter 
^^^
Well basically he has tweaked the Itechs dsp to get the most from the LMS.

I believe he mentioned tweaking the room response to suit my taste....just don't know how to do that.
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