Fi Q 18 Upgrade

[TheMonolith2001 0]

I have been running a Fi Q 18 tuned at 28Hz off 1500w RMS for a few years now and I love the way it sounds however, I think I want to upgrade to get more output. I will also be upgrading to 2000-2500w RMS. Honestly I really want more of what I have now in terms of sound because I love the way it sounds but I do not want to get a second one because I do not have the room and I do not want to upgrade to 3000-3500w RMS. I do not compete and I never will. I do not care what numbers I hit or what it sounds like outside the vehicle I just want loud good sounding music. I listen to almost strictly electronic music which to be honest is kind of all over the place in terms of frequencies but I can say my current setup handles it very well. I love the low bass. Should I just tune higher (33Hz?) and put 2K to the Q? It is fully loaded. I started looking at the BL/BTL and the XCON/ZCON. What would you guys recommend for me?

Thanks guys, I know you are probably tired of comparing subs but I hope I have at least described my goals clearly enough.

[Notorious97200 339]

1) If you have the room, a second one can be a good choice. You don't need to run full power to enjoy those subs !

But you won't find those Fi Q brandnew, there is a new line of Q  now.

2) 2 15"s on 2500 watts : that can be good too.

3) A single BTL or Zcon 18 should be an upgrade in my opinion.

I went from Icon, to Xcon, to Zcon ! It was always an upgrade in output, not in accuracy on music.

It's up to you, now !

[Liro213 36]

I have both xcon and zcon. Both subs are amazing and incredible. In terms of loudness and output , zcons take the cake. xcon doesn't fall too short behind in that segment. To my ears the xcon has more control and plays very smooth and accurate thruout the frequency band. They   could get very loud if you want them to. Def one of my favorite subs.. Zcon on other hand does almost the same only it Is much more brutal when volume is up, and bass is "thicker" when playing low. 

both subs can't be pinned against eachother, both do amazing depending on your goals.

[///M5 2,833]

2k won't buy you anything.

New box will.  Either in tuning or to house a larger driver.  Need to figure out how big it can/you want it to be.

[Infinite913 381]

On 1/13/2017 at 11:02 PM, ///M5 said:

2k won't buy you anything.

New box will.  Either in tuning or to house a larger driver.  Need to figure out how big it can/you want it to be.

This is truth. Box design could help alter what your hearing currently and gain some different frequency response but ultimately its what kinda gains your wanting to see.

[TheMonolith2001 0]

So I've been thinking about this for awhile and everything you guys have said so far makes sense but I am already at the 18 inch driver and 8 cubes. I was thinking about building a 33hz box instead of the 28hz I'm at now. Definitely the cheaper option! TBH I was thinking about tuning to 33hz AND getting a 2K amp just because I'm in the market for a new amp anyway and box rise is a thing. Plus then if I ever do decide to change my sub depending on what I get I can probably (hopefully) just drop it in the box. I don't really know that much about the SSAs because I've never used them but from what you have described it sounds like the XCon would be a good match for me. Being loud is super fun and all but so is turning it down to appreciate how good it sounds so I don't think I can dedicate myself to the loudest driver.

Should I go to the maximum 10 cubes? I ask because the easiest option by far would be to shorten the port in my current box and stay at 8 cubes. It's pretty well built (and heavy) being made out of birch with metal bracing/double baffle/etc. It is already the maximum dimension of my trunk though the only other direction I can build in is up. (hatchback) I will check how that effects port ratio tomorrow I'm getting a bit tired tonight.

[SpeakerBoy 64]

You will NOT hear a difference from 1500w to 2000w.

 

My box for my Fi 18 is 9.5cu@27hz and I'm very content with it on 1500rms. My next upgrade is going to be 7k rms in a smaller enclosure.

It takes a significant amount of power to hear a difference. In a perfect world, DOUBLE the power is +3db which is just enough to be able to even notice. You'd need 3k+ to do that. Build a new box, focus on a great huge ass port with  decent enclosure volume and that'll tell you whether it's time for a system upgrade or not.

Oh and, don't use the term box rise. It doesn't mean what you may think it does and isn't really relevant in this situation. You're playing music, every note is going to fluctuate impedance. If you were building a burp box for one frequency it'd be slightly more relevant to measure.

Edited January 24, 2017 by SpeakerBoy

[TheMonolith2001 0]

I know that the rule of thumb is double the power for +3dB increase but if I am buying an amp either way I figure why not get the 2K? I wanted to invest in a real nice Zapco that will last me a long time and possible future builds.

Why would box rise not be relevant? I'm not saying I don't believe you I just want to learn why. If your impedence is different at difference frequencies wouldn't a 2K amp basically help more at some frequencies than others? I was going to try and make sure it was always getting at least 1500 RMS at full tilt and then eq down the frequencies where it was getting more. I can do that somewhat with the gear I have now but a processor is in the near future as well.

If doing this really is a waste of time that actually works out better for me because I can go for the 1700ish RMS A/B instead of the 2000  RMS D class. I know that is a whole argument in itself but to me there is a big SQ difference that is worth the extra power draw. My ears may be more sensitive than most. My family is made up of musicians and sound technicians! Depending on the frequency I can usually notice a difference of 2dB. None of us have much experience with speaker building though.

As for the box I have right now at 8 cubes if I knock out one of the port extensions it brings me to 34.56Hz tuning. Port would end up being 20.5 tall X 5.375 wide X 17.125 deep. Does that seem like a solid plan or should I go for the 10 cubes?

[Jay-C76 333]

More power would not necessarily mean larger net volume internally. I have built many, I mean many test enclosures for the icons I have and it yielded different results almost every time to the ear. To some people they can hear very minor variances in output and tuning with design & materials. However this does involve wasting a buttload of materials scrapping old ideas. That's why a well designed and built enclosure can trump more power almost every time.

[///M5 2,833]

On 1/24/2017 at 1:07 PM, TheMonolith2001 said:

Why would box rise not be relevant? I'm not saying I don't believe you I just want to learn why.

The first answer is the obvious one.  There is no such thing as box rise.  The box will surely have an impedance curve but this means a rise and a fall.  While this curve will definitely mean your amp is delivering different amounts of power along the curve it is not rise.

It is really sad this is a misnomer in the car audio world.  Stems from some history in single note competition.  A fart box will surely also have a curve.  When playing a single note you are only concerned with the impedance at that note in that particular install.  That isn't rise either, but it is higher than nominal in almost every fart box so some moron keyed the term box rise and started to mislead noobs all over the internet.

Beware of nonsense spewed at other forums.  They are full of people who repeat what they have heard and state "rules of thumb" which none of are correct in car audio.  The exception being that as a rule of thumb you can discount everything you read on other car audio sites.

[TheMonolith2001 0]

Okay so I guess I had accepted "box rise" as the slang term for impedance curve of a box but I shouldn't. Fair enough. It is true I had never heard the term before car audio forums. I thought it was assumed that it was a curve and the rise part was just referring to how you might go from 1 to 1.5 ohms at some point for example. I have definitely noticed the regurgitating of "facts" you speak of as well.

I happen to have a large amount of extra 3/4 MDF lying around. I guess I'll just try some stuff and remake it in birch when I like it. It just kind of sucks to have to do it this way instead of being able to somehow arrive at what amount of port area/tuning/cubes I should be aiming for. I guess screw around in WinISD some more? There is definitely a difference in sound with the materials used. Look at all the different woods and processes used to make drums to get different sounds. A drumhead in a drum/speaker in a box are both moving/vibrating membranes moving air in an enclosure really.

Let me ask you this as well: When I am messing around with time alignment/leveling/eq if I for example lower the volume of my front right tweeter by 1dB and I notice a significant change in soundstage to the left does this mean I have some kind of super hearing?

[///M5 2,833]

Depends on what your system is playing.  Area under the curve is the sound.  Ie, on music that change should be noticeable. 

[TheMonolith2001 0]

So I got myself a Zapco ZX500.2 and I gotta say the hype is real. Worth every penny. I like old school amps so I'm skeptical of anything new and I have to admit my Q has never sounded so good or loud. I don't think I'm going to change anything else at this point substage wise the max volume is just unnecessary. (yeah yeah said that before lol) I wired it at 4 ohms bridged which is 1750ish watts. I wonder what the explanation for this is? Crazy slew rate? I don't know what the Zapco is rated at but one of my other amps was rated at >50 V/µS and the other two don't say. 

Now I just have to get some distribution blocks so I can redo my mids/tweets. I have a Pioneer PRS-D800 on the mids and the tweets off the head unit. I'm going to switch it over to a PPI PC2300 Chrome and PPI Art A300. Should be a pretty cool looking amp rack and its all A/B! RIP electrical haha.