Need some advice....

[Fish Chris]

Okay, first off, I'm about a 60% SQ, 40% SPL kind of guy. Loud is great, as long as it's below 30hz.

Anyway, the thing I'm kind of locked into, is my power situation. {my old RF Power 1000, 5 ch. makes it really tough to switch. Great amp, but puts all your eggs in one basket }

So, I've got about 760wts (into 2 ohms) to play with. I could make 960wts into 1 ohm, but I really like the efficiency, and cleanness of my amp run into 2ohms vs. 1ohm.

As for space, I can easily build / fit an enclosure of 7 cubes, after port and speaker displacement. I might be able to squeeze 8 cubes, if that 1 extra cube would make a big difference.

I've been running two 12" eD 13Kv2's for about 3 years. They have done great. But I finally cracked one of the spiders, and so now it pops a little on fast hits.... + after 3 years, I'm just kind of board with them anyway.

So, I decided to go with two 15"s this time around. I think I probably got ahead of myself, and like a dumbass, I ordered a Dayton HO 15" yesterday morning (first of two)(they do offer a 45 day money back guarantee though). Of course I researched them, and everybody says they are fine SQ subs. Of course the price was not bad either...... But geeeez, not much of an X-max

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

So now I'm wondering if I should have spent a little more.... well, ($200 more for the pair) of Fi Q 15"s ???

Sorry for my long post, but if you read nothing else, the $10K question is >

Given the same 760 wt RMS, would I really see (hear) much difference, if any, between a pair of Dayton HO 15"s, and a pair of Fi Q 15"s ?

Thanks in advance,

Fish

PS, An even crazier (but possible) option, is that I could go with my same 760wts RMS, and all of the 7 to 8 cubes of space I have available, ran to just one 18" Fi Q ! Heck, that would cost about the same exact price as two Dayton HO 15"s, (a lot less than two 15" Fi Q's) and because of the huge difference in X-max, would (in theory) move twice as much air !

My only concern there is, I do "also" listen to a lot of old school stuff, with normal, slightly higher frequency, guitar and drum bass. Just not sure "how fast" an 18" can really be ?

[Fish Chris]

Oh hey, here's the totally dumbed-down version of my post above, for anybody that just doesn't care to know any of the other details, or is too lazy to read them...

> Given the same 760 wt RMS, would I really see (hear) much difference, if any, between a pair of Dayton HO 15"s, and a pair of Fi Q 15"s ?

Much thanks,

Fish

[bassrace]

The pair of qs prob need more powa but the single 18" should do the trick

[Fish Chris]

Thank you Bassrace.

One Fi Q 18" huh ?

Well check this out, I'm pretty good at math. I just sat down and calculated out the volume in liters, of air moved with the maximum stroke of my:

eD 13Kv2's (for two) = 2.19 liters

and a pair of the Dayton HO 15"s = 2.7 liters (only a 19% gain from my eD's )

and for a single Fi Q 18" = 4.5 liters !!! For a greater than 100% gain !

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So still, my only concern is whether the Fi Q 18" will be fast enough, and tight enough, to play nearly all of my music well..... and not "just" my techno bass stuff (no worries about this stuff.... I'm confident it will pound rediculously hard, and deep).

Hmmmmmm......

I have until Friday to decide whether I send the Dayton right back with Fed Ex, instead of accepting it.....

Peace,

Fish

The pair of qs prob need more powa but the single 18" should do the trick

[6berry]

what it will play is based heavily on the box that its in. use the right box and it can play whatever music you want

[kam311]

what it will play is based heavily on the box that its in. use the right box and it can play whatever music you want

X2!!! It's all in the box man

[Fish Chris]

Don't worry. The box will be spot-freaking-on. I'm totally anal about tweaking every dimension, calculating port areas, lengths, frequency of tuning, etc, etc. I just spent 2 hours tweaking over the RE box designer.... (BTW, I don't do drugs, in case you were wondering ... hard-core OCD sufferer though.

Anyway, this is what I came up with:

Box width 32"

Box height 30.5"

Box top depth 19.5"

Box bottom depth 27"

Wood thickness .75"

Sq port height 29"

Sq port width 4.25"

Sq port length 1 18.25"

Sq port length 2 16"

Total port length 41.375"

Sq port area 123.35 sq in

Box volume 8.167 cu ft

Tuned frequency 28.35 hz

I'm sure most of you guys have seen the RE program I was using.... This one > http://www.reaudio.com/LPort_Box_Calc.php

Only thing I'm not sure of, is whether it takes into account speaker displacement. I assume not, since they don't know what subs you will be using ? That's why I'm calling this box 8 cubes.

But hey now, I have heard a million X's, and said so quite a few X's myself, that "the box is everything"...... But is it literally "everything" ? No differences between a 12" and an 18" with SQ ??? Hmmmm.

Peace,

Fish

what it will play is based heavily on the box that its in. use the right box and it can play whatever music you want

X2!!! It's all in the box man

[shogen]

try using the Torres Calculator... See if those numbers generate the same results... I don't like RE for some reason, just doesn't seem right... Could be that I'm stoopid though...

[Fish Chris]

Shogun, thank you. I will look up the Torres Calculator now.

BTW though, have you ever seen, or heard of a port tuning nomogram ??? It's the actual graph that pretty much all of the modern box building programs are based on.

Here's what it looks like:

I could sit here and explain it, but you can probably figure it out on your own anyway.

I print up several of these for every box build, then, even if I have used a modern PC program to design the box, I go back and check everything with my old school port tuning nomogram

I already did this for the design above, which I ran in the RE program. Came out pretty much spot on

Peace,

Fish

Edit: Okay, so I downloaded the Torres program.... That thing is freaking awesome ! Only thing was, inputting all of the same numbers, it shows my box being a net of only 7 cubes, rather than the 8 cubes the RE program shows This sucks, because if this is true, I don't think I can squeeze 8 full cubes into my available space

Granted, it only brought my tuning up from 28hz, to 31hz.... But still, I want a low frequency monster ! Hmmmm.

I think I will sit down tonight and calculate out my exact cubes long hand, with pen, paper, and calculator.....

try using the Torres Calculator... See if those numbers generate the same results... I don't like RE for some reason, just doesn't seem right... Could be that I'm stoopid though...