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Discussion Starter #1
With the added listeing time today and tweaking stages still, i've noticed that the accuracy that i have with my tempest, Sealed 4.5cf box seems so accurate that it could almost be too accurate for my tastes, but mabey i'm just not used to it yet. But the sub does sound awesome, and i'm loving it, still trying to decide if i need to port it or whatnot, because i think i'm used to a little higher internal delay, whereas my Sealed box has <8ms delay straight down to 20hz, not sure if thats good but seams that way. Its almost too accurate for my tastes.

Now i've been trying to level match it with my front stage and such, and some songs it matches very well, others it really dosent match that great, what songs and such should i use to specifically work on midbass/sub xover, i have them right now at 63hz and it sounds good, but some times the sub is overempasized or the midbass is over emphasized, i can't get it right on. Xover b/w the midbass/tweets are very good right now.

Only problem is midbass and sub, conversion, and sub level matching.

Opinions, suggestions?
 

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maybe find the freq. area your sub is more pronounced and decrease it using the parm. eq and q narrow near it , you will also need a captain crunch decoder ring to understand what i just wrote! sorry its past my bed time
 

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Too much accuracy??? That's a horrible problem to have! j/k lol Is that huge box in your TC?!!? Just got in from a late night out and my mind is still racing, so this will be a long one, ha ha!

TUNING

Regarding tuning your Subwoofer & Mid-bass transitions: I would start by using the Autosound 2000 Test CD #101 or the Sheffield/Autosound 2000 "My Disc" Tracks #59-62 to determine the overall frequency response of your sub and mid-bass in your vehicle. Chesky also has some great Test CDs and there are sites where you can download test tones as well. As far as musical tracks, recently, I’ve been using the Diana Krall “Love Scenes” CD to dial in my sub and mid-bass just because it’s a familiar recording, but there are so many others that obviously will work well.

The Autosound 2000 Test CDs have slow & fast Frequency Sweeps from 20Hz-20kHz and Progressive individual tones from 10Hz and up of 5 seconds or so each to determine the response of your system. It's pretty obvious just by listening to the Sweeps for the peaks and dips in your car’s response, but it would be best to have an SPL meter or an RTA. You’ll hear areas where you may have cancellations as well, and the SPL at any given frequency may shift from Left to Right due to Phase interactions and cancellations. This will really help to smooth out your response and let you know where you have problem areas that may not be able to be fixed with EQ due to the phase cancellations/interactions.

For the Sub-to-Mid-bass transition, you may find that you can use the Crossovers and Slopes in your 8053 to smooth out the response. I’m sure you know that all vehicles have natural resonance’s or “cabin gain” usually in the 40-80Hz area and usually again in the 150-350Hz range. If you have a peak in one or both of these areas, use the XO to smooth them out. For example, instead of having your Sub-to-mid bass transitions (LP on the Sub & HP on the mid-bass) BOTH set at 63Hz with a steep slope, try setting the LP on the sub at 45Hz with a 12dB per octave slope, and the HP on the Mid-bass driver at 80-100Hz with a 6dB per octave slope.

Of course, your settings also will be determined by the usable range of each driver. Sometimes you’ll find that you can actually have the HP on your Mid-basses/Mid-range driver at 350Hz or even higher with a 1st or 2nd order slope! I’m pretty sure that this was the case in Scott Buwalda’s 240SX IIRC. These are just examples.

I've used the EQ/Analyzer in the Behringer DEQ2496 Ultra Curve Pro with great success. For the cost, it's about the most accurate and least expensive tool available for this. The Behringer mic works great with this unit and has a very wide and flat frequency response. I’ve used these mics to make some incredible recordings as well!

I’ve also found that having an independent subwoofer level control/knob up front is a great advantage, especially for day-to-day listening while driving. For Competition, you can leave it centered or at a specific, marked setting and tune to the appropriate organization’s Test Disc, which should give you consistent results.

Every recording engineer and music artist has different tastes, and obviously, different CDs have different EQ curves, etc. I loved my old Sony ES CDX-C910 head unit and the XDP-210EQ and XDP-4000 EQs because you could dial in the EQ levels for a specific CD and every time you put that CD in, it would change the EQ settings to what you had programmed for that disc! I believe it was called “Disc Memory”! I wish the P9 and 8053 setup had that!

Well, I’m not a professional musician anymore, but I used to play drums/percussion and alto/tenor sax for about 13 years before I gave it up and transitioned into photography. I define "accuracy" as faithfully reproducing the recording or live performance exactly as the musicians and/or recording engineer intended. If it doesn't match this, then it is not accurate. Of course, you need an "accurate" and consistent reference to determine this, so it's almost impossible to achieve especially since "accuracy" can be so subjective with our different perceptions. What I believe to be accurate may not be what you believe to be accurate. We all "hear" a little bit differently. It makes it a bit of a challenge! With my test CDs, I use a good set of headphones as a reference (mostly for tonality.)

A recording of a live performance that you have been to (especially at the same venue repeatedly) is one of the best references, but still far from being a perfect reference. Why? Because there are so many variables, even at a live performance. #1. You can't replay the actual live performance over and over to log it permanently into your aural memory. Unfortunately, our aural memory is very short term! Obviously, active musicians have an advantage here. #2. What you hear is usually very dependent on where you are located at the performance! I may hear the horn section with perfect detail in one area, but move to another location in the "house" and they may seem muffled or diffuse, or overpowering, etc. #3 The sound can vary even at the same performance from night to night. The engineer may change XO settings on the stage speakers to dial things in from night to night. Or he may change the instrument or vocal microphones/locations, or have to replace a faulty piece of equipment, etc. If it’s a purely acoustic, non-amplified performance, the hall or venue itself will sound different depending on how many people are in attendance! Obviously, playing in an empty hall sounds VERY different than when that same hall is filled with people and hot air! Even the weather can affect the sound! Dry and Cold or Hot & Humid, the sound or response will change! There are obviously some very good, and some very bad concert halls, stages, venues, etc. Some have predictably good and consistent sound from almost any location, but most do not. So many variables, so much fun!

Whew! Hope that wasn't too much! Just my .02 FWIW. Anyway, I hope this info is useful. Happy tuning!
 

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Discussion Starter #4
Bud that was one hell of a packed post, i dunno what you did tonight but you seemed on fire in that post lol. I've been tuning some alot lately with the focal #4 disk, and some other random CD's that just have pretty a pretty heafty range on them, some i can get to sound awesome, others are sorta bla.
 

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LOL! I've always wanted to get my hands on those Focal Test CDs! Are the ones you have the "Disc du Demonstration" or something else? Where did you get yours? I've got just about everything else, but I've gotta get those!
 

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Discussion Starter #6
Well i've got the Focal #4 and #6, thats it, I really want to get some of the sheffield labs and Autosound cd's, but dunno where to get them. I got mine a month or so ago when someone had hosted them and put the link's up here on a thread, search for them, they may still be active but i doubt it.

Really want to get ahold of lots of test cd's, i have probobly 5x as many bass test cd's than actual SQ cd's, and i've got a SQ system, so time to rack up on the test cd's.

The focal disks are just a mix of some dynamic and SQ oriented songs, thats it really, no phase tests, stage tests, or anything......
 

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maybe your midbasses just aren't punchy enough....
 

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demon2091tb said:
Well i've got the Focal #4 and #6, thats it, I really want to get some of the sheffield labs and Autosound cd's, but dunno where to get them.
Tell you what, I have the Autosound cds #102 and #104. Lets say I designate you as my friend who will "hold my backup copy" for me in case of a fire, and I do the same for you with the Focal cds....that way we both make out, sound good? If so, PM me and I will back them up tonight and get them in the mail to you first thing Monday AM.
 

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Discussion Starter #10
Aight good deal, heading to work right now, so when i get home tonight i'll make some "back ups" for you, and i'll PM you then, ok.
 
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