JLAudio Fathom f112/f113

[WmAx]

Chris(Wmax),

What are your thoughts on using the JL audio subs 12" and 13.5" with the EP2500? What about the fact that they are 3 ohms nominal 2.47 and 2.41 ohms(Re) DC resistance respectively? The EP2500 is only good to 4 ohms mono is it not? This was the issue I have run into in looking at constructing my own.

Let's assume you want to run the EP2500 in bridged mono. First, any good amplifier has to account for electrical phase angle changes in a loudspeaker, some of which are severe, otherwise the output devices (transistors) will self destruct from current overload. There is always a safety margin in a properly designed amplifier. Besides, as you should know, many speakers may claim a specific nominal impedance, but in reality, are much lower. Rarely does a well designed amplifier self-destruct in this case. The JL Audio products, however, are usually not far from specifications. As for personal experience, I have run drivers that are slightly under the rated loads many times in the past, with almost no failures. The one failure I have experienced was from running a 4 ohm subwoofer pair on a lower end line 8 ohm Pioneer receiver for several years in a bedroom speaker system. Also, the amount you drive the the subwoofer overall will also vary the probability of overload. As you drive the subwoofer harder, the voltage increases to the driver, and with that, current. I think that it is very unlikely that you will overload an EP2500 that can output 2000+ watts in home application. I doubt that you would use more than a few hundred watts, unless you were turning the subwoofer up to very high levels just to show off in order to try to knock pictures off the walls. The EP2500 has a very conservative self protection system, also. If you do approach overload, it's going to cut output automatically before you can damage it. Of course, realize, you are going to need a dedicated 20 amp line just for the EP2500 and subwoofer.

Now, let's assume you want to use just one channel of the EP2500. That's nearly 1000 watts RMS at 3 ohms. It's rated 2 ohm stable in stereo mode.

-Chris

 

[ssabripo]

What is different?

what do you mean? I already told you all the JL would care to share with the public. Different motor and motor characteristics, different suspension, etc.......they all lead to different T/S parameters, and ergo a likely different SQ. If you want exact numbers on how the Le or Qtc changed, you need to call JL themselves and perhaps you'll get lucky and they will share it with you.

Chris(Wmax),

What are your thoughts on using the JL audio subs 12" and 13.5" with the EP2500? What about the fact that they are 3 ohms nominal 2.47 and 2.41 ohms(Re) DC resistance respectively? The EP2500 is only good to 4 ohms mono is it not? This was the issue I have run into in looking at constructing my own.

just add to Chris' excellent post, I've used the EP2500 numerous times in my DIY subs. They great amps for the price, no doubt. However, as mentioned earlier, I would consider one of crown's or QSC's mid to higher end offerings if you going down this route.

The EP2500 is a cheap clone of the RMX, QSC are using better quality parts.

EP2500 pic
http://home.pacbell.net/lordpk/proamps/EP2500-1.jpg

RMX2450 pic
http://home.pacbell.net/lordpk/proamps/RMX2450-1.JPG

Which parts do you consider better quality?

re: transformer size. The newest pic of the EP2500 shows a transformer
size that appears to be the same as RMX2450. I had doubts last year because
I saw an older pic.

re: warranty
A good warranty and good service to repair your amps is a good thing.

Some will say you can almost get 2 EP for the price of one QSC that's right because you need a spare just because you are never sure when you gonna hit the power switch what gonna happen.

The EP and RMX will have the same chance of failure.

For the XLS series the picture are from the B series the new D series as real heatsink

Post a pic of the D series XLS guts I doubt Crown made any upgrades to
heatsinking because they *still* don't rate those amps for 2 ohm stereo
nor 4 ohm bridge mode, lol..... They could easily if they had any good heatsinking
inside. You'd think if they did heatsink upgrades they'd change their specs for
the better..

http://www.crownaudio.com/amp_htm/xlsspec.htm

XLS602 heatsinking. lol .. ware..da beef?
http://img337.imageshack.us/my.php?image=picture009gs9.jpg

which leads us to: What is the difference between the XLS 602A amp. and the XLS 602D amp?

Bridge-Mono switch, re-laid out circuit board, new front panel, more front panel metering and a little more output power.

David Glass
Applications Support Engineer
IQ Systems/Engineered Systems/Touring
Crown International

http://www.crownaudio.com/forums/index.php?showtopic=1429

**************************************************************
XLS402A: Stereo Mode Power Rating: 8 ohms: 260 watts, 4 ohms: 400 watts, 2 ohms: 570 watts, Bridged Mono Power Rating: 8 ohms: 800 watts.

XLS402D: Stereo Mode Power Rating: 8 ohms: 300 watts, 4 ohms: 450 watts, Bridged Mono Power Rating: 8 ohms: 900 watts.
**************************************************************

Interesting that the original was rated for 2 ohms/ch, but not 4 ohms bridged.
Someone must have made a marketing error.



so what does all this mean? It means that the EP2500 is a fantastic amp at $300, and should be in your list of amps to make this fathom clone. However, to really push the 13W7, if you can muster the cost, there are better options in Crown and QSC.

 

[WmAx]

Which parts do you consider better quality?

You can not tell from the pictures. And the pictures are a little unfair, as in the EP2500 pic, the perspective has the transformer in the back, making it look smaller, while the RMX amp has an almost direct above top shot. I have an EP2500, and it's a recent one. I have not seen the old one in person, opened up. But the current one, I don't see where they could get a larger transformer inside. It has maybe an inch or little more clearance from the nearest internal objects.

But what parts are supposedly worse? The Behringer even uses the standard high grade circuit boards with redundant double-soldered side traces for durability reasons, according to the Behringer site.

Just trying to stand back as a 3rd party observing the claims; I don't know if their is *any* substantial quality difference, as I have not seen anyone substantiate this common claim with credible data/facts. What would help is to list specific parts, their specs, and the relevance according to the specific circuit and actual applied usage as it relates to the specs, so that I (and others) have a realistic perspective of this quality difference.

-Chris

 

[WmAx]

**************************************************************
XLS402A: Stereo Mode Power Rating: 8 ohms: 260 watts, 4 ohms: 400 watts, 2 ohms: 570 watts, Bridged Mono Power Rating: 8 ohms: 800 watts.

XLS402D: Stereo Mode Power Rating: 8 ohms: 300 watts, 4 ohms: 450 watts, Bridged Mono Power Rating: 8 ohms: 900 watts.
**************************************************************

Interesting that the original was rated for 2 ohms/ch, but not 4 ohms bridged.
Someone must have made a marketing error.

Are these rated 2 ohm stable in bridged mono? If not, how are they a better choice than the EP2500?

-Chris

 

[nasd90]

Umm... I thought we were talking about JLAudio.

In any case, I was down in the St. Petersburg area of Florida for my best friends wedding where I was fortunate enough to be the best man... and I went to a place called 'Sounds Terrific' which is an extremely high end audio dealer, including JL Audio... Well, I had a chance to demo the JL Audio Fathom F112 and was blown away, even with this entry level SUB in the JL-Line... So, I bought it and it's sitting in the back of our SUV waiting to be taken back to Tallahassee tomorrow.

All I have to say that it's... no joke.

We also got the opportunity to check out this Sonus Faber 7.1 system running a Randy Travis Live Cd. When my friend and I left the store, we literally, for the 1st time in our lives, were Country Music fans.

Cheers,

Nick

 

[enviro-pestcontrol]

JL Fathom-13

Just recieved my JL-13 All I can say is this thing is a beast, I just sold a DD-18 I had for a few weeks here and it was noticably lighter than the JL Fathom. Hooked it up sending signal from my Denon 5803 Reciever / Amp And a Denon 3910 DVD player. Watched Nemo with my 4-yr old for the 1000-Th time , But like never before. The DD-18 Was nice and my SVS PB2- Plus2 where great! , But this Fahtom-13 brings Bass Fidelity to the next levels. My Dedicated Theatre Room " Sound Proofed " 16-Long 12- Wide and 8- Feet High. The sound presure was clean and the Bass was sooo Crisp. Amazing form such a small Box it Fits so nicely in my Room And Takes up so much Less space. Front Controls What a Concept!
Now I am considering picking up another before they raise the prices.

 

[mike c]

i'll wait to get to know you better first before I remove the great big chunk of salt that I took with your "comment"

 

[Warpdrv]

i'll wait to get to know you better first before I remove the great big chunk of salt that I took with your "comment"

Good one Mike, I agree its all in what you find value in...

I can't wait to see and hear an SVS Ultra for 1/2 the price, yes its significantly larger in size, but hey....

 

[nasd90]

Now here's a guy, who puts his heart on his sleeve and tells you about the wonderful time he had with his 4 year old and his incredible experience with the JLAudio Fathom, one of his first posts, and you've got to bring him down. Come on, be an adult. Now, cost aside... because that seems to be everyone's little 'comment' about the Fathom.

Have you heard a JLAudio Fathom ?

Don't let these Player Haters bring you down Enviro-... I for one own a Fathom and love it. I tested out a few of the other high-end subs, but wasn't impressed. Most are ported and just don't do it. There's a reason there's a PATENT on their product fella's. It took about 5 seconds listening to the Fathom and I was done.

You're right, it is a beast.

Nick

 

[mike c]

exactly the reason I have my doubts. first post ...

guerilla marketing anyone?

 

[nasd90]

You think I work for JLAudio... haha... Nope, I'm a computer geek, working at a Fortune 200 Advertising Conglomerate.

It's not marketing on my end, they don't need it.

Once again, have you ever heard a JLAudio Fathom 12 or 13 ??

You seem to be quite the sub expert... Must have taken you some time to get all those little jpeg's together to create one line of subs... and you even put the 'x2' in there. You have some serious photoshop skills.


Nick

 

[mike c]

You think I work for JLAudio... haha... Nope, I'm a computer geek, working at a Fortune 200 Advertising Conglomerate.

It's not marketing on my end, they don't need it.

Once again, have you ever heard a JLAudio Fathom 12 or 13 ??

You seem to be quite the sub expert... Must have taken you some time to get all those little jpeg's together to create one line of subs... and you even put the 'x2' in there. You have some serious photoshop skills.


Nick

huh? you realize I wasn't talking about you when I said guerilla marketing?
a bit defensive are you now.

no, I haven't listened to any JL's because there's no one selling JL's here. and the ones trying to sell to me "internationally" is selling it at 3300 USD plus shipping via FEDEX.

I am no sub expert, and I'm shitty at photoshop or any graphics software (I used corel draw btw) ... but your point is?

 

[nasd90]

My point is:

1. Let someone praise JLAudio without nonsense

and

2. Wut's up with all the subs in your sig ?




It's cool man, I'm just bustin' your ballz.

N

 

[mike c]

My point is:

1. Let someone praise JLAudio without nonsense

and

2. Wut's up with all the subs in your sig ?




It's cool man, I'm just bustin' your ballz.

N

alright, let's chalk this up to a misunderstanding.

1. it'd be cool if it was a real person, not some guy registering multiple usernames and just plain marketing. that's why I said I'd wait to get to know him first, he had the benefit of the doubt.

2. the first three are what I have already, the last four (the ones with x2) I have on order.

 

[Warpdrv]

I personally love the JL113, but the price is not what I feel is worth it...

Now owning a couple of SVS's already, I know they will really have something to measure up to the JL...

I auditioned the JL locally and was very impressed. Then I was in a home theater that had 4 of them in the same room... Dam basketball players...

Now that was something to behold.

 

[mike c]

if the 113 was truly 2600$ like the AVS thread says ... I'd have ordered one already. but for 3300 plus 500 bucks shipping, I'd gladly order a second DD18 ...

but I'm going to try some other brands first before double dipping. I thought I was gonna fix up my dedicated HT #2 into a 3500 cu.ft. room, I didn't anticipate it to be 4200-4500 cu.ft. I wonder if I will still get the pressure I'm getting in my current 2600 cu.ft. room.

 

[Warpdrv]

Plus the fact that they are raising the prices too boot....

I was talking to the dealer and he was blabbering something to the effect that the Gotham is $9K now, and it will be going up to $11K...

 

[billy p]

Then

Plus the fact that they are raising the prices too boot....

I was talking to the dealer and he was blabbering something to the effect that the Gotham is $9K now, and it will be going up to $11K...

indeed, it's a good time to buy. Lets face it these subs aren't for the common man.

 

[ParadigmDawg]

It still cracks me up how a bunch of intelligent men argue over subwoofers.

 

[Warpdrv]

It still cracks me up how a bunch of intelligent men argue over subwoofers.

Somehow you have been led to believe that I am an intelligent man...