Punchy Subwoofer - Page 2

I listen to modern rock, classic rock, jazz and contemporary and it all sounds insanely clean and punchy with no distortion whatsoever. In fact, I've never heard either one of my X-Refs lose composure even when testing everything out below reference. They just kept on punching.

You keep repeating that the Emotiva emits "no distortion whatsoever."

This statement is totally untrue, but since you don't have the knowledge base or equipment to measure the amount of distortion, you resort to hyperbole to try to continue to justify your $1,200 purchase.

Even the servo controlled Velodyne DD and DD+ series generate distortion though it is limited by the user variable servo.

In this link:

http://www.hometheaterhifi.com/volum...03-part-2.html

Dr. Johnson shows a hand full of graphs measured at different frequencies:

Of course the $5,000 MSRP Velodyne is a much more capable sub than anything Emotiva sells, which is as it should be. The point is that great sub like the DD-18 still produces distortion.

At 15Hz and 100 db THD was 4%.
At 20Hz and 100 db THD was 2.5%
At 25Hz and 100 db THD was 2%

When the DD-18 was tested by Keith Yates, he was able to measure 10% THD at 20Hz and 115db.

All of these figures are extraordinary.

Again, the point is that given a lack of experience measuring distortion, you exaggerate the lack of distortion produced by the Emotivas. Of course Gene DellaSala talked about the overly steep 28db per octave LPF and the limiter in the Emotiva X-Ref 10. While the LPF and limiter do keep distortion relatively low, that comes at the expense of low frequency extension and output.

Isn't there a difference between measurable distortion and distortion you hear? I am talking about the distortion you hear. I dont doubt there is no measurable distortion. Kind of the same premise as higher quality speaker cables measuring better in terms of resistance but can the measurable difference actually be heard? I dont think so and neither do 99% of people who do double blind studies.

I dont hear any distortion no matter how loud Ive played the X-Refs. That's all that matters to me.

Couldn't tell yah. I've never heard the Epik Legend but I have heard good things about it.

The one and one of the most important types of distortion you're forgetting about is dynamic compression. No way will a single 12" keep up at reference levels and that is most certainly very audible. Even for 99% of the population. Those who don't are simply in denial.

The X-Ref's limiter prevents the driver from losing composure. Emotiva was pretty conservative when setting the point in which it kicks in. That being said, I am not sure what "Dynamic Compression" is and probably wouldn't even know what it sounded like. All I know is that the bass still sounded good when running at reference levels. I would never listen to anything at reference but I just wanted to hear what everything sounded like at reference. Lastly, I have two 12 inch subs. Maybe two keeps up at reference?

Here is a graph of Polk 505 showing compression:

http://www.hometheaterhifi.com/volum...er-4-2005.html

As sub volume is increased not all frequencies increase the same.

An example of severe dynamic compression can be seen in the top graph on this page.
http://www.audioholics.com/reviews/s...0-measurements

Note how the shape of the frequency response changes as the spl's are increased as seen in the yellow and blues sweep lines. This is what happens when a small sub cannot continue to maintain consistent low frequency output when higher levels are called for.

I see what your talking about but wouldn't this differ if measurements were done "In Room" rather than outdoors. I also see that the reviewer stated when the sub was being driven to max output the voltage limiter kicked in to protect the amplifier and kept the system from audibly distorting.

I am lead to believe, the dynamic compression you see in the charts is due to the limiter not kicking in fast enough for the sweep tones which is completely realistic and understandable.

Most importantly, after pushing the sub past its intended output range, it never misbehaved and all of the sweeps "sounded" clean with no sign of cabinet resonance or erroneous driver noises.

Same here, I have heard nothing but good things about the Epik's, Legend and Empire. Probably great musical subs.

Who listens at reference level other than a fool determined go deaf?

Dynamic compression is not something that would sound like bad noises. It simply means that the sub cannot put out deep bass in proportion to the rest of the frequencies as the sound levels go up.

That's what its really all about in audio. Can you hear it. Again, can you hear it. There is distortion and then there is audible distortion. How good are you ears? Can someone say DBT?

'Limiter' being the key word in here. I'm sure this sub is nice if you live in an apartment or don't like listening at levels that are somewhat 'spirited'.


You sir, are quite misinformed. Have you ever watched a movie at a ....movie theater? If you have then you should be deaf by about now.

IIRC the Jester has said he can't use a true deep bass sub because he lives in an apartment, and not a single house. So he has said he has no use for strong output to 20Hz because of his neighbors.

Seems to me that even 30Hz at a significant volume will travel through walls and upset neighbors. The question becomes are the neighbors the kind that will complain or not. I don't buy my subs based on what the neighbors might hear, but that's only my way doing things.

I don't live in an Apartment and have never said so. I live in a end of group town house with one neighbor who lives to the left of me. My sound room is my basement which is 90% under ground and surrounded by concrete except for the shared wall which consists of 2 layers of dry wall with a fire wall in the middle. When I first set everything up, I asked my neighbor if I could come inside of his house with my system cranked. The first time I did, you could hear a lot of bass inside of his house but no high frequencies. I then rearranged the subs and put them on the other side of the room where the wall is not shared being how I live in a end of group. On this side of the room, the walls consist of a outer layer of concrete, then insulation, then foam board and then dry wall. After I moved the subs to this side, you could still hear a tiny bit of bass in his house with my system sitting at about 5db under reference. The bass at this point was only heard every once in a while, and you almost had to really listen for it. My neighbor told me that if he hadn't known what we were listening for, he probably wouldn't even hear it. I have been told that the wall construction on the end side of the house is probably doing a good job soaking up the bass.

So now, I hope you understand where I'm coming from and that yes, 20Hz at high volume levels would be MORE audible to my neighbor than 30Hz at high volume levels. Stop acting like you know everything because you didn't even know what type of house I lived in. You know nothing about my living situation. Next time you talk about me, at least get your facts straight.

Chuff Chuff Chuff

I mainly listen to Jazz and Contemporary but I do mix in some classic rock. I have pretty much listened to everything except Opera and Country. I still have yet to find anything that sounds bad through these subs. It also amazes you just how much output such a small cube can throw out. Like I said before in other posts, I haven't heard any type of distortion come out of it nor have I heard it lose composure. There is only one thing you don't get with this sub and that is flat extension down to 20Hz. You do however get high output, clean tight bass and a very accurate sound. You can't really expect a sub this size to get down to 20Hz flat while only costing $600. Just remember, there is no perfect sub in this price range. You just have to decide what your willing to give up.

Yea man, I heard that was a bad ass sub.

What a limiter does IS dynamic compression. The limiter keeps the system from responding fully to the increased input levels. Usually to keep the driver, not the amp, under control. If the limiter was too slow, the system would get pushed into greater distortion or other undesirable characteristics.

There's nothing wrong with the design choices apparent in the Emotiva. The reason it doesn't distort when driven past its capability is that the limiter keeps the sub from going past its limits. So it's clean but quieter than it "ought" to be. It's not performing miracles, though, just operating in accordance with its design, which holds the output down to keep things under control.

The room will dominate any in room measurements. To compare subs, one measures in conditions that are not distorted by the room. Then a purchaser who knows their room can determine what will work best for their needs or desires in their room.

Thank you for the information. It completely makes sense.

No sir you are misinformed.

http://www.dangerousdecibels.org/edu.../hearing-loss/

Please read so you can understand. Also, leaving a movie theater with your ears ringing is not a good thing.

Makes complete sense. Over the years, many retired firefighters from busy fire departments (like mine) will go deaf at a early age due to constantly having to listen to the siren. Particularly, the ones fire trucks use which are the loudest vehicular sirens available. They draw 280 amps so smaller vehicles can not power them. I don't know if you have ever heard of the Federal Q but it is very effective. The only down fall it has is that it is so effective, the noise in the cab is just as loud as outside of the cab when you have the windows down. The Federal Q's are designed to throw out square sound waves at 125 decibels. According to study's, a blast of 130 decibels can cause immediate hearing damage. Anything over 110 which is the sound of a train passing by can cause hearing loss over time as well.

I would never want to listen at levels over 100db for a long period of time or often.

as the pot calls the kettle black...

Your 100% right. I'm not in the least afraid to admit I have acted immature. However, I'm not going to sit back while people assume things and talk ****.

I'm done though. Arguing that is

Haha....I f'ing love subwoofer threads. I should buy stock in Orville Redenbacher.

It is pretty fun. I know I've had fun.