or Connect
AVS › AVS Forum › Audio › DIY Speakers and Subs › 6 DIY eD A7S-650 kits with FP14K clone
New Posts  All Forums:Forum Nav:

6 DIY eD A7S-650 kits with FP14K clone - Page 6

post #151 of 249
"LTD is basically claiming that all DACs are exactly the same and send an exact copy of the input signal to the output jacks..."

that is not what i said dave. i said "the dac conversion rates that modern gear run at do not degrade bass signals."

if the gear is rolling off your frequency response such that you can't get 2hz out of your system, that is a different matter.

analog gear can just as readily roll-off frequency response, but you know that.
post #152 of 249
Quote:
Originally Posted by MKtheater View Post

Hey, what is that graph showing?

It shows a bi-quad curve for a specific sub with +10dB of boost and alteration of the naked knee in a loopback measurement. One is using the Berry DCX, one is my SEQSS, one is the Marchand Bassis and one is the MiniDSP 2x8.

It's answering bass addict's Q. Yes, you can successfully use a shelf and several additional PEQ filters to get very close to a bi-quad, but I wanted to show that all of those solutions has a different roll off result. Many digital PEQ solutions have a roll off that eats into the shelf, so I didn't include those because the answer in those cases would be 'no'.

LTD,

My answer showing roll off variance was directed to bass addict and had nothing to do with my answer to your claim that all DACs are the same. There are variations in DAC architecture and the results have not been tested in the case of a subwoofer. The introduction of noise would be my 1st area of investigation. There is already nearly zero available information for below 20 Hz reproduction and absolute zero is the case for Delta Sigma converters, much less the rest of the components in a $300 do-it-all outboard digital EQ.

There are a huge majority who say that limiters are 100% transparent, the fact that they constantly and infinitely change FR is irrelevant and DSP is also transparent, especially so in the subwoofer passband. They also apparently agree that the values chosen for DC blocking caps is arbitrary and that that approach is 100% acceptable.

I believe I've done more research on the subject than anyone. My conclusion is that known and unchanging preset curves is better than limiter-induced infinitely and constantly changing curves and analog is the more transparent way to achieve the goal vs digital. I'm not going to say more than that (as I did in years past regarding everything else I was constantly put on trial for and had to slog through, over and over) because I don't have the time or the inclination. Folks believe what they want and like to hear what they want to hear anyway.
post #153 of 249
Thread Starter 
Quote:
Originally Posted by bossobass View Post

Yeah, I was assuming you did not use a shelf with the CHTs but rather cut the top end to get flat to 5 Hz because it was the logical conclusion after looking at the graphs and your comments. Adding the shelf to the current system is the method I prefer (obviously). If you get a chance, do a close-mic at one of the drivers without and with the shelf at the same output level, all the way down to 2 Hz.

So the DCX rolls off the most, no wonder I can never get to 3hz. My graphs always drop under 6hz.
post #154 of 249
Thread Starter 
BTW guys, here is the reason why I like this system better than any others before. I turned up the spl until I hit 130 dBs or close to 10% THD. The effects of the room were crazy, the 10hz sine wave blew the theater doors open, I need to lock them during this stuff.


207.jpg

157.jpg

thd10.jpg

I hit 127.5 dBs with 10% THD but wanted to see what 130 dBs would do.

thd12.jpg

You can also see my response as well. I get lower without the DCX in the chain but I use it for EQ.
Edited by MKtheater - 11/24/12 at 9:33pm
post #155 of 249
"the 10hz sine wave blew the theater doors open"

lol, mk, you are awesome.

nice frequency response and nice set of measurements.
post #156 of 249
Thread Starter 
I have 9 dBs more output than my CHT subs at the same 11% THD at 10hz.
post #157 of 249
What mic were you using there? When I was measuring at these levels, I was hitting the limits of my wm-61a. I was also nearing the edge of the power that the MA5050s could put out. I'd measure again after the FP14000 upgrades, but don't have any mics that can give me a good reading at these levels.

... first world problems ... I know.
post #158 of 249
Thread Starter 
I am using the Calibrated behringer mic and clone amp. The drivers were at their end with the 10hz sweep but I still had more in the tank from the FP14K. The amp is a beast. I love my 2100 cubic feet room. I also am running 12 of these guys so I have 4 more drivers than the CHT subs.
post #159 of 249
Yep. 130dB at 10Hz messed up the seal on one of my doors to the patio. What are you calibrating your spl levels with MK?
post #160 of 249
Wow 130DB at 10hz?!
post #161 of 249
Thread Starter 
Quote:
Originally Posted by Ricci View Post

Yep. 130dB at 10Hz messed up the seal on one of my doors to the patio. What are you calibrating your spl levels with MK?

I am using my RS meter with sub test tones. I set the mic at 106 dBs and it said I could measure up to 130 dBs. Things started to sound bad with the 10hz at 11.8% THD at 129.5 dBs. 10 % THD is about my limit for quality so I hit 127.5 dBs there. I am not sure why the dB level on the graph did not get copied. The 15hz and 20hz was a breeze though. My goal was 123 dBs reference levels clean, this surpasses that easily. Madaeel can confirm the experience since he has heard it.
post #162 of 249
How do you know what spl level the tone being sent to the meter is? I guess that is my question is what signal are you referencing the spl to?
post #163 of 249
Thread Starter 
I am not sure I understand the question. I am running the generator set to sine waves and calibrated REW with my RS meter set at 106 dBs. I then just turned up my MV to 0 dBs and then raised the LFE channel in 5 dB increments. REW showed me 5 dBs increase everytime.
post #164 of 249
Thread Starter 
I set my MV to 0 dBs and then went to my mic at the LP and measured the spl at the mic with my RS meter. I used REW's subwoofer test tone to calibrate. It measured 106 dBs and then went to the computer and put in 106 dBs for the calibrated mic and REW said this measurement was good to 130 dBs. That is when I just tuned the LFE channel up in 5 dB increments.
post #165 of 249
My ACO Pacific rig (7012 mic, 4012 pre, PS9200 power supply) is rated to 160dB, but I can't measure that high because the interface will clip, so it isn't the mic that dictates the max dBSPL.

What Josh is asking is what calibrates your rig. You answered that you use your RS meter to 106dB, but you have to be more specific. Do you place the RS meters cap at exactly the same spot to calibrate as your Berry mics cap when you measure and what frequency do you generate to read 106dB?
post #166 of 249
Thread Starter 
Quote:
Originally Posted by bossobass View Post

My ACO Pacific rig (7012 mic, 4012 pre, PS9200 power supply) is rated to 160dB, but I can't measure that high because the interface will clip, so it isn't the mic that dictates the max dBSPL.
What Josh is asking is what calibrates your rig. You answered that you use your RS meter to 106dB, but you have to be more specific. Do you place the RS meters cap at exactly the same spot to calibrate as your Berry mics cap when you measure and what frequency do you generate to read 106dB?

I placed the tips right next to each other and I used REW's subwoofer test tones so pink noise I guess. It really does not matter if I hit 130 dBs as all I know is that reference for any movie is very clean, at least from 10hz and up. I ran some sweeps and my response stayed the same up to 120 dBs. 5hz gets squashed at 105 dBs though but from 6hz and up I am good. It does sound much stronger than ever when I let it rip, I remember madaeel looking over at me during FOTR and said what the hell was that, ULF? It was the chairs shivering or wobbling. I ran it 5 dBs hot at that time.
post #167 of 249
Quote:
Originally Posted by MKtheater View Post

I am using my RS meter with sub test tones. I set the mic at 106 dBs and it said I could measure up to 130 dBs. Things started to sound bad with the 10hz at 11.8% THD at 129.5 dBs. 10 % THD is about my limit for quality so I hit 127.5 dBs there. I am not sure why the dB level on the graph did not get copied. The 15hz and 20hz was a breeze though. My goal was 123 dBs reference levels clean, this surpasses that easily. Madaeel can confirm the experience since he has heard it.

When you say sound bad, do you mean in terms of mechanical noise from the drivers (since 10hz is definitely the feel range)?
post #168 of 249
Thread Starter 
Distortion.
post #169 of 249
So you are able to HEAR the distortion at 10hz?
post #170 of 249
Damn dawg!
That is a sweet setup! Nothing like subs galore!cool.gif
post #171 of 249
Thread Starter 
Quote:
Originally Posted by gpmbc View Post

So you are able to HEAR the distortion at 10hz?

Yes, I can. The harmonics at 20 and 30 hz are 110 dBs. Trust me, that is Audible. These drivers sound awful above 10% THD. I have enough of them that reference levels are well below 5% THD and they sound great for that.
post #172 of 249
Ah I get it now! The distortion down low influences higher up. I've heard the effect before but never really thought about the root of it.
post #173 of 249
Thread Starter 
Quote:
Originally Posted by gpmbc View Post

Ah I get it now! The distortion down low influences higher up. I've heard the effect before but never really thought about the root of it.

I have played my LFE 10 dBs hot before and no movie ever hit this loud. The bass in movies is just clean even at 5 dBs hot with boost down low. I have never had this much spl from any system before from 20hz and lower. The CHT and 190v2 systems had more 25hz and up. To compare my CHT's hit 122 dBs at 20hz and 121 dBs at 10hz with 10% THD measuring the same way. So even if the levels are off no matter what I have 9 dBs of more output. I can tell you for sure I have never had the bass that loud before from 10-20hz, ever. This is why I would never put 8 LMS 5400's in my room because I already have tons of headroom if needed. I would probably hit 137-140 dBs with them and never use that output.
post #174 of 249
I can't testify as to whether James' subs can hit 130db at 10hz since he didn't do those sweeps when I was there. We just didn't have time. I did go there to see if I could detect ULF and how noticeable it is. I see why many who have the capability, Bosso, MK, NOT, Ricci etc, tout its effects on a movie and listening experience and why if you can, get a system that can reproduce the full soundtrack. We watched WotW and the lightning strikes that have content below 10hz when they run in the house wobbled the chair and my body pretty good. The LotR with the Balrog was equally impressive and noticeable. We did play Bass I Love You and the 7hz note was played clean and loud as well.

The funny thing is it's hard to describe the feeling for me. I've seen some say its like being under water. There is a pressure, but to me it just feels like my whole body is tingling and the air in the room is pressing in on me. Every time I felt it I recognized it was ULF. No it's not all the time of course, but I would definitely spend whatever I could to achieve that feeling in my theater.

To me a massive screen and being able to play at or close to reference makes the experience like being in a movie theater. To have subs that can play as low as these guys' systems just completes the effect. IOW I gotta have it.

Here's a short video my friend made while we were there. He's a pro, but unfortunately James has a dark theater and we dragged a lamp in there just to get any shots.

Sorry I took so long James.

http://vimeo.com/53050429
post #175 of 249
Whoa, great vid, however.... all it did was wet my appetite for more!

I didn't note the running time prior to viewing.


"I did go there to see if I could detect ULF and how noticeable it is. I see why many who have the capability, Bosso, MK, NOT, Ricci etc, tout its effects on a movie and listening experience and why if you can, get a system that can reproduce the full soundtrack."

"but I would definitely spend whatever I could to achieve that feeling in my theater."

"To have subs that can play as low as these guys' systems just completes the effect. IOW I gotta have it."


cool.gif
post #176 of 249
Thread Starter 
FOH,
Yeah, the video is short but it gets a pic and an idea. My room is dark and since my lights above my speakers were put in before going BFM array crazy so the arrays cover the lights and makes the front stage dark. I wish they got a full view of the front stage but I will just take another pic for that. I am waiting for Madaeel to comment on the speakers because I think they made just as big of an impression. These little eD 13's put out more displacement than one might think, and having 12 makes things very easy. I built one sub for $500 total which included the EMF wood and dual drivers. I think they are a bargain at that price. I have done the same THD tests with my CHT subs and my cinema F-20's and these not only went much higher at lower THD, they made a big impression on my room during the tests. I have now found brand new rattles in a previously rattle free room.
post #177 of 249
Quote:
Originally Posted by FOH View Post

Whoa, great vid, however.... all it did was wet my appetite for more!
I didn't note the running time prior to viewing.
"I did go there to see if I could detect ULF and how noticeable it is. I see why many who have the capability, Bosso, MK, NOT, Ricci etc, tout its effects on a movie and listening experience and why if you can, get a system that can reproduce the full soundtrack."
"but I would definitely spend whatever I could to achieve that feeling in my theater."
"To have subs that can play as low as these guys' systems just completes the effect. IOW I gotta have it."
cool.gif

Yah sorry about that FOH. Eric wasn't too happy either. I guess until you see the video on the computer you can't get a good idea of how it'll look. He took plenty of video but it's pretty dark in there as James said. We'll probably head up again sometime and try to get some better footage. With James' consent of course.smile.gif

Eric isn't that much into audio as much as me and after watching a couple demos he looked at me and said "you gotta get this". That summed it up for me. I really can't wait to enjoy movies that way, and he can't wait for me to get a system that HE can enjoy that way. James' screen goes from the floor to the ceiling too so the effect is just perfect. A screen that is matched by the sound.

I do wish we could've changed the HPF setting to see how dramatic the change is when a sub is filtered at different frequencies, but we barely had enough time to watch what we did. All I know is it just takes movies to another level and I'll spend a large chunk of my budget to obtain it.
post #178 of 249
Quote:
Originally Posted by MKtheater View Post

I am waiting for Madaeel to comment on the speakers because I think they made just as big of an impression.

Ahhh yes. The DR-250's. Man I love those speakers. I wish I had more depth in my room so I could put them behind the screen. Actually I *might* be able to if I can put all the subs up front. It could happen.

I really don't understand why in that speaker shootout they didn't like them. I have NEVER listened to movies that loud and only once did it bother me and that was LOTR in DTS at reference. That is insane loud. I also think that movie is recorded very hot. Every other movie clip sounded amazing at or above reference. Never once did Eric or I think it was too bright or harsh. They just sounded nuetral. I wonder if maybe the amp/electronics they were paired with made them sound bad because for us it was a pleasure to hear them.

What's crazy is James had two of them for each LCR channel. One is plenty. They handled every thing with ease and could've easily gone louder.

I would put them in my room in a heartbeat if they weren't 22" deep. They're bulky but that's the only negative I can think of.
Edited by Madaeel - 11/26/12 at 11:16pm
post #179 of 249
Quote:
Originally Posted by Madaeel View Post

I really don't understand why in that speaker shootout they didn't like them. I have NEVER listened to movies that loud and only once did it bother me and that was LOTR in DTS at reference.

Something was wrong for sure, I couldn't even take the sound of those speakers at 30 under reference they were so painfully bright and I don't have a big sensitivity to supposedly "harsh" sounding speakers. We played with the eq but it didn't seem to matter. It would be great to be able to hear them in a treated room with the eq dialed in right. At our GTG they sounded like someone turned the eq up as high as possible between 2 and 4 khz, it was like a very sharp needle going into your brain.

There is NO way what you heard at MK's is what we heard in my room.

Awesome stuff guys, love that video - want to see more!
post #180 of 249
Thread Starter 
That is why I had no problem buying them, I knew how to dial them in and my room helps. You just need to time to adjust them and I finally got them perfect! I would have thrown them away on first listen. I told you guys I can listen at reference all day with these speakers. I mentioned putting ribbons in them and Madaeel said I would not change a thing.
New Posts  All Forums:Forum Nav:
  Return Home
  Back to Forum: DIY Speakers and Subs
AVS › AVS Forum › Audio › DIY Speakers and Subs › 6 DIY eD A7S-650 kits with FP14K clone