Help me upgrade my diy.

jonone

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So I have been enjoying my diy td15h+, I'm primarily a music listener and this driver is super clean and and music sounds deep fast and accurate, definitely an upgrade from my bk xxls400.
I kind of stumbled upon this diy setup after being slightly pushed into the driver and cab size etc, and I can't quite help but think I'm missing out a little, the driver does roll off slightly at the bottom end and because of the vented phase plug you get a little chuffing below 25hz by this is only noticeable playing a 20hz test tone, it's not a real world problem per say as you don't hear it in films or music.
But it's like the ultimate bass/mid bass driver in fact it's killer in this sense, but I can't help feeling it's not a true sub in the 30hz and below sense.
So the av15h has been released and I've also talked to nick about about a hst15.
My box size is 17.5" cube so I roughly make it 45l with my 950w plate amp and a driver, or about 50l if I get rid of the plate amp which means I can get have more power in the sense of getting somthing like a inuke3000.
I would like to retain that clean musical which I get from the td15 so the av15 appeals, I wonder if the higher le of the hst is noticable real world?
So would one of you guys help me out and model the above against my td15h+ I would really appreciate it.
 
Hst
Re: 3.6 Ohms

Fs: 16.6 Hz

Qes: 0.34

Qms: 6.02

Qts: 0.32

Le: 3.6

Sd: 117.85 in^2

Vas: 141.6 L

BL: 24.5

Mms: 527 g

Sensitivity: 85 dB (1W/1M)

Sensitivity: 88 dB (2.83V/1M)

--------------
Nick
 
I may add that John didn't seem to think in my enclosure there is much difference between the av and td as the bottom end is determined by the enclosure size, so to take advantage of the xmax it seems all I can do is add more power if I want to keep my existing cab size, but how much is to much for the av15/ hst?
 
I can try and model it later anyway. There's been quite a bit of debate on how best to model a high Le driver though (based on reducing motor strength) so I'm not entirely sure how accurate that will be.

The key point I will make though is that the subwoofer is just the 1st way in a system so you can't design a sub in isolation of the rest of the system. I would say this is especially true when comparing a wide bandwidth woofer like the AE drivers against a sub only driver like the HST. I'm pretty sure John @ AE would say something like use the HST to 50-60Hz only for example. A reasonable design might be a beefy sub to handle the lows and then crossing to a high quality woofer. Lots of ways to do this obviously.
 
Thanks matt, legend as always!
I was also thinking in an ideal world I could keep the td15 and almost use it like a midbass unit and have another sub like the hst from 40hz an down. Hsu recommend of somthing like this, but they say to have the sub up front and the midbass behind you.
I experimented with two bk 4oo in this way to try and get rid of my dip around 200hz by having one right by the side of me like a coffe table(I'm limited by position) but if the xo was to high it more became localised with volume and kind of ruined the sound stage as it pulled it away from the front.
I don't know if this was down to the xxl400 I should try the td15 in that position?
So I was thinking I could put the sub nearfield maybe an hst12 or 15 and keep the td15 up front.... but it's extra expense and I think my wife would kill me!
 
experimentation is good, it keeps you off the streets after all :D

I don't really know how to compare these 2 drivers though as they're so different, for the sake of argument I have put them in the same box and given the same power

upload_2015-5-12_23-47-21.png


black is the HST and grey is the AE

all this really shows is the increased sensitivity of the AE though

if you swap to rated power handling (1500 vs 800W) then you see the HST start to pull ahead below 30-40Hz as you'd expect

upload_2015-5-12_23-49-21.png


I haven't tried to look at excursion here at all

To cut a long story short, I think you need to be able to design this yourself in order to make a sensible decision. There are just too many variables for someone else to be able to optimise remotely.
 
Thanks matt!
The thing is to much experimentation will get me kicked out onto the streets! :D
Im going to forget two subs for now it's not going to happen, so it's down to if I upgrade to the av15h or not.
Can you do me a last favour and model the av vs the td in 45l with 950w.

then finally the av15 in 50l with an inuke3000, I would like to see what happens with xmax if that's ok.
Thanks dude! :)
 
In my Op I would look at a better amp to run the ae or run the nu3000 bridged,
 
Can you do me a last favour and model the av vs the td in 45l with 950w.
looks almost identical to me under 70Hz in output terms when each is given rated power, the TD has a lot more above 70Hz though. The difference is that the AV15X is ~3-5mm within xmax all the way down to 10Hz whereas the TD hits xmax at 20Hz. I don't see that as particularly meaningful though tbh as targeting serious sub 20Hz output from a single 15" seems unwise.

Obviously the AV is within xmax at rated power though so there's the q of whether you can eke a bit more out of it by giving it more power (we're talking the odd dB here though so doesn't seem a big deal to me).
 
Did you model the av15x or h matt? ( sorry to sound picky I thought h was for a smaller cab?)
So are you saying my td15h+ hits xmax at 20hz in 45l with 950w but the av15h will be about 20mm down to 10hz, If so then it's pretty much taking advantage of both the drivers?
The plus is I wouldn't get the chuffing below 30hz with the av15 even if there isn't a big spl advantage, like you say your not going to get that with a single 15 anyway.
I would rather not use an external amp so if there is only a small spl advantage than its probably not worth it for me.
Thanks again!
 
Did you model the av15x or h matt?
both, the H uses a touch more excursion down low to deliver the same output.

So are you saying my td15h+ hits xmax at 20hz in 45l with 950w but the av15h will be about 20mm down to 10hz, If so then it's pretty much taking advantage of both the drivers?
yes though I didn't fiddle with anything to do with box stuffing, this was just a quick comparison. I'm not sure what you mean by the last statement.

are you sure the chuffing is because of the phase plug btw? sample thread - http://www.avsforum.com/forum/155-diy-speakers-subs/1347410-those-ae-td-woofers.html
 
What I mean is John was saying I'm not using the full xmax of the td15 in my box with my power, but you seem to say I am? We have had this before haven't we! : )
Ive read that thread, interesting....when I put the chuffing question forward to John he just said "sorry about that and he hadn't tested them in small sealed enclosures" ?
Thinking about it, it's better described as a fluttering, so when you get past 30hz roughly where you can actually hear, the fluttering is louder then the test tone, but like I say this is playing a pure 20hz test tone not real world listening.
Do you think I might be past xmax would this account for the noise? I also run the 25hz lift function of my antimode as the sub rolls of after 25hz, this gives it a kind of house curve by dropping the overall volume but lifting the bottom end could this cause over excursion?
 
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In my Op I would look at a better amp to run the ae or run the nu3000 bridged,
I tried to use an online modeling program and it says the av15h will just be in xmax with 2500w (3000 bridged) in 50l, what do you think scott?
 
I also looked at matts guide to the 3000 bridged power and it says it goes down to 1200w so do you model for that?
 
There are a few questions there; can the driver take that sort of sustained power without melting the coil? Do you actually need that much power to deliver the output you want? Is it a good thing to drive a sub all the way to xmax?

I suspect the answers are no, no and no :)
 
Ha ha, I'm sure you probably right.....I think I'm just getting carried away!
I would rather stay with my plate amp anyway , I have a young child,so I need simplicity in my life at the moment.
So if I fancied a change to the av with my current setup do you think the x or h works better in the 45l with the supposed 950w?
 
I'm back :rolleyes: I've also ordered a av15h :)
I'm thinking of keeping the td15h+ up front and using the av15h near field crossed over quite low circa 40-60hz so I don't need to boost the low end of the td15 and means I keep the 10hz signal the the antimode discards when the filter is in use.
Planning on giving it the recommend 1000w via the new bk plate amp, so just the cab size to sort out. Do I model to be just within xmax at 10hz?
Here is the online calculator I use with 95l, can someone please check it as there always seems to be a discrepancy with the one matt uses and I think it might be over xmax?
image.jpg1_zpsdyqfu9ab.jpg
 
That bottom graph looks to be within XMax - I'm not familiar with that program, though!
 
It's a free online program, I've got a Mac.
I wouldn't mind someone checking though as when matts helped me in the past his program seems to model differently and it's normally over xmax
Thanks, jon.
 
a lightly stuffed sealed AV15H in 95L given 1000W monsters through xmax at ~25Hz according to WinISD

upload_2015-6-23_17-59-26.png


I think the box is too big tbh, the step response you've shown looks overdamped to me. I would take it down to 50-60L max.
 
This is what I mean!....thanks matt!
Can I ask what it looks like in 60l? I take it thats 60l not including the driver?
What does the driver take up? 5l? And can I ask the amount of stuffing I should use!
Sorry dude, I appreciate all your help, you will be rewarded in your next life. :)
 
Can I ask what it looks like in 60l?
this gave a Q of a ~0.6 IIRC, basically you lose ~1dB off max output at 20Hz which is pretty much irrelevant.

I take it thats 60l not including the driver?
What does the driver take up? 5l? And can I ask the amount of stuffing I should use!
tbh I don't think it matters, the actual driver will measure differently to this model anyway so just treat the model as something to get you into the right ballpark. This means something in the region of 60L exc the driver is probably as big as you should go. The ideal way to fill is to take impedance sweeps as you go but otherwise the rule of thumb is something like 0.25kg per ~28L, aka just ram it in there til it is pretty full but the stuff isn't really compressed. Alternatively, for a sub, you can just line the cabinet appropriately.
 

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