EndersShadow

Got testing with JTR imminent too.

HOT DAMN.... GOODY!!!!!!!!!!!!

This is me jealous of your access to a CNC router to build stuff..... .

Looking good, looking forward to seeing graphs.

Awesome!  I'm glad some of these tests were useful.

 

There's a lot of debate about how or even if these tests translate to real world use, but regardless of that one of my main goals was to test all the amps under the same conditions for comparisons sake. 

 

Before I tested the Crest CC amps I knew their 10hz and below performance was sub-par based on experience with sealed subs and real content.  This amp testing confirmed my findings. 

 

There are many other examples of this but bottom line I've found how the amps perform during this testing to correlate very nicely to real world use. 

Yes, my concern was the sub 20hz Crown debate which you put to rest.

Once I get things settled a bit my goal is to purchase a Balanced MiniDSP and play around with a low shelf filter to bring up the bottom end, so I needed to make sure the amp had "somewhat adequate" power below 20hz to accomplish my goal.

With a single sealed 18 I get tons of bass, still not enough for my personally, but the point of this is that I want to try my best to even out the SPL of the bass given the Equal Loudness curve and I think the shelf filter will help with that a bit.

When I add it, I will also evaluate just how much if any of the sub 10hz stuff I can actually feel with my large room and potentially then add a highpass to ensure I dont clip the amp with that content, given how much the wattage drops below that point, and by doing so potentially gain some ability to crank it above 10hz more.

Luke, wanted to thank you for this thread.

As a result of your testing I bought a secondhand XLS 2000 to drive my Ultimax 18 in a 4 cubic foot flatpack (which I bought after extensive research on this site and looking at the drivers available in my price range).

First one is done.

Springtime I will buy the second kit and another XLS2000 to drive it, and will have both Crowns on a dedicated 20amp circuit .

It should be close enough to not matter. Not sure if the bracing or driver cut-out will work without modification though.

Thanks..... turned out that didn't happen, and may not ever happen, but I did get to play with the ported Chane sub, and MAN does that thing hammer.......

I cant WAIT to get my hands on my 18" ultimax box in the next week or so.......

Hey Ricci... thought you might like to know I may soon be in possession of that Chane SB-113 box and use it for a dual Ultimax 18 build......

You don't happen to have written down what the actual internal cubic footage is of that box?  I see it appears to have a 2" front baffle with the rest of the box being 1" thick.  Dimensions are 22.5 Tall x 20 Wide x 20 Deep.

I care because I just got the Denovo Audio Flatpack w UM18 kit, which measures 23 Tall x 20 wide x 20 deep and uses a 1.5" baffle and the rest of the box is .75" thick.

My thinking is save some cash and buy just the enclosure (buddys re-using the driver in a diff box) and stick another Ultimax driver in it and have it match the box I have.

But I'm not sure how much interior space there is once you account for the difference in box thickness and bracing....

Indeed it is.  

Looks like thats the amp I'm gonna try and snag here soon then.

Get it for my current ported stuff and then start saving to go sealed in my room with a couple 18" subs and try to get more ULF.

WOW, that XLS2500 is still a good performer down to 10hz it looks like...........

Absolute worst case those XLS numbers may be 45-50w high. 

Yeah... since I need 200-400 wpc max @ 8 ohm from the entire amp (ie bridged) I'm not worried....

I am thinking about a 2500 later on to maybe a HST-15 or 18 or some other larger sub in a sealed box trying to enter the depths of ULF but thats likely a pipe dream till my new home pipedream materializes.

Those tests are good.  The "High-Resolution" thing did lower the voltage a bit, but for the voltages the XLS was putting it was probably only ~2v. 

 

For the CEA burst stuff I just tested, those are the starting resistances, and with a reactive load like my subs the resistance will go up with more power.  Think of those CEA numbers as a best case number. 

 

Maybe I should get some heater elements and a bucket!  That's was nice about a non-reactive load, the impedance doesn't change with frequency. 

Ok, thanks.  I was mainly making sure the XLS stuff was "close" since your testing somewhat invalidates the whole subsonic filter debate. For the sub I'm building now its ported too so it will need a subsonic filter, but I'm using EQ that would potentially go lower than 20hz

Luke... does this mean the testing you did with the Crown XLS was flawed?  I'm a bit over my head here so wanted to just double check if that was the case.

Posting from the car sucks lol...

Ignore me

^yeah he sent me pictures of em later that day.

He's got em sanded down and repainted already lol...

I will prob be headed down there in a few weeks myself for a unrelated sub project and look forward to seeing/hearing them!

PS I'm currently passing through Louisville ironically enough

No worries mate. I'm slightly jealous of my buddy for getting them lol.

I take it they got picked up today?

Ricci I need your contact info. I know a guy in Eberfeld IN who will take both your Chanes and your JL sub.

He will contact you and make arrangements to have hen picked up tomorrow

Thank you sir! So looks like about 700 wpc @ 10hz if not bridged.

Makes me think this could be viable amp for a set of dual UM18s

As for which frequencies to test, I'm thinking 10, 20, and 40hz?

 

Think 5hz is also worth while?

May as well, doubt the output will be that much, but then you wont get asked later on for that number.  I'd also do 60 and 80 just to be safe on the top end too.  Mainly so you've got a decent test of what most AVR's can crossover at for the LFE of a sub.  I'd guess output should be about what the spec's is give or take, but again I'd just bench it once with a decent set of frequencies to satisfy as many folks as you can.

If its a pain to test at all those frequencies then I'd not worry about it, I just haven't seen near the bench test spec's for the XLS stuff I've seen for the iNukes like the 6000 which is what this is mainly compared to/competing with...

Also not sure how much its worth testing it at 8, 4 & 2 ohms for each.  I'd maybe see what spec's are out there for the iNuke 6000 and try to get the specs of the 6000 at the same ohm/frequency so you can do as close to a direct compare as you can.

Personally I am not planning on running it at 2 ohms as I figure if I run 2 subs at 4 ohms, there will be sections it will dip below, and since its rated for 2, it means it should handle those dips without a issue, whereas a 2 ohm load dipping may trigger protection...

So not sure how worth it a 2 ohm load specs is v a 4 and 8... but I'm not nearly as smart as 99.9% of the guys here so I defer to you or others on that call.

I'll test the XLS 2500 first and try to get it done by this weekend.  

No worries mate, I'm in no rush on my end as I haven't made any purchases just yet (and it still may be a month or two), but hope to have solid proof one way or the other so the issue can be put to rest.

I hope it goes the way I want as the Crowns fans aren't as bad as the iNukes .

Nice setup man.  I cant wait till whenever you get back to testing amps with your new setup.... I've been waiting for someone to bench the Crown XLS models to look at the sub 20hz stuff and put an end to the subsonic filter "Is it or Isnt it" an issue question.

I'm just hoping that whenever the Crown XLS amp gets tested we can put to rest this 20hz highpass thing and see in the real world what effect if any it has on the SPL of a sub.

I've also got a Dayton UM18-22 for grabs. Brand new, the box has never even been opened.

 

$240 shipped.

Am I missing something or does this driver graph better than the HST-18 on your compared graphs? Both in 4 cubic square foot boxes...

Hmmm...... anything else on that list a page back your selling Ricci lol......

Your close enough for a daytrip for me lol......

I'd love a Gjallarhorn  if I had room for it and my wife wouldn't kill and stuff me in it lol......