posted
I would go with an Alpine 701. It is easy to control from outside the vehicle. Since you will be getting tested with you out of the vehicle, you don't want to set the RTA in the vehicle. Go with a digital EQ also it will make tuning 100% easier. the 701 is by far the cheapest. You will have to buy it used since Alpine stopped making it.
The 701 will give you time alignment, phase, crossover (with multiple slopes) and a graphic EQ for the front, rear and subwoofer. All these will be used to maximize an RTA score.
The key will be control and the 701, F1 and Zapco DSP 6 will be the best in that area.
*free unsolicited advice from an SQ guy who has had to do RTA most of his competing life*
I'm assuming you can make changes between SPL and RTA measuring.
Cross your subs over low. Like 40hz or lower. It is MUCH harder to control the cone of a subwoofer than it is a midbass driver. Use your midbass driver to play from about 40hz up to about 1khz. Then let a midrange play from 1khz up to about 6khz or so. Then the tweeter up from there. Don't get real agressive on the low end of anything other than the midbass or you will smoke something at that level with pink noise.
From the way I read the rules, the best way to hit the cap is to do a ski slope. Let your subbass in the sub 40hz range hit the cap, and then do a gentle slope down to about 500hz or so, and then flatten it out to 20khz. Don't make the slope to big or the bottom will fall off the screen and you will get killed on the score.
When you are tuning--take a tape measure and measure where the mic is in relation to the steering wheel and the door jamb. Mark it on the tape measurer (you can get free ones at fabric stores). Then put a dot on your door jam and on the steering wheel. Measure from there when they set the mic up. A movement of one inch in any direction can GREATLY change your score. so getting the mic in the EXACT location of where you tested is the most important thing. Other thing is to use as few speakers as you need to hit the cap. the more speakers you have the harder it is to control and the more reflections you have. The 701 will allow you to turn off individual speakers. So you may need two midbass drivers but only one midrange driver and one tweeter.
posted
Thats good info for people just starting out on using EQ's. Anyone else chime in theres alot of people looking at doing this class have no idea what EQ's are out there or where to get them.
I will probably do an online tutorial when I get to setting my PPI up.
-------------------- -Donald Hebig -All Out S.P.L. Saskatchewan's dB Drag event promoter -Check the Termpro homepage partners for the companies I support. Posts: 2600 | From: Borden, Saskatchewan. Canada | Registered: Feb 2000
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posted
Its basically hit and miss for what available with eq nowadays. I own a PPI deq230 (2 actally)..one just sourced from ebay recently. Audio control and Phoenix Gold made pretty decent gear back in the day in this catagory (audio control eqt/eql and the digital models now..phoenix with the eq 215 and 230) Ironically enough there was a Phoenix gold digital eq on ebay today. Other vendors are Kicker with the 5 band a nd 30 band eq and well as RF sixty.2.
You may also come across the older rack style or "RANE" gear that was modded for car use. i don't know if Speakerworks still makes their version. I know Crossfire did a version as well (wish I would have kept the set I acquired)
Hope this helps someone.
-------------------- Chuck Whitney Jr. '95 VW Jetta III 2008: World Finals:Street Stock A - 4th place Regional 2009: New Season..New Class..getting back to basics
posted
Andy I have a question; How would an older alpine pxa-h510 (701 predecessor) do in this category.
-------------------- Chuck Whitney Jr. '95 VW Jetta III 2008: World Finals:Street Stock A - 4th place Regional 2009: New Season..New Class..getting back to basics
posted
Audiocontrol eqt 30 is the chit. nif they still make them.
-------------------- TEAM XTREME LOUD AUDIO THE LOUD CROWD Team Dc Sound Labs. Posts: 2789 | From: Springfield Ma | Registered: Apr 2004
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posted
What I know of the 510 is that it isn't very flexible.
When RTA matters, I would not use any analog EQ's. Analog is to hard to tune with. If you have a decent curve and make a change with the EQ and it doesn't work---you will spend 20 or 30 minutes trying to get back where you were before that change. With a digital EQ you just hit a button and you are back where you were. Go digital on the EQ.
You also want an EQ that either has center points the same as the measuring device (which generally means 1/3 octave) or you want a huge number of parametric bands. If you are not familiar with using an EQ, then skip using a parametric. It is much more complicated to set up correctly.
I have no doubt that with an Alpine 701 and an active system I can maximize the RTA portion of this class. Unfortunately, I'm an SPL moron, so I have no idea what to do for that section. Install also isn't that hard.
If anyone is in my area and wants some help with RTA just let me know. I have an Audio Control RTA and will soon have a TrueRTA--and those will get us close. To get a perfect score though we will need the Termlab RTA. It should only take a few hours to lock it down
posted
Dont forget about the audison bit one. 1/3 octave time allinement for each channel digital with wired remote of tuning via laptop. can save different curves for rta spl daily driving etc. sold 2 of them but no chance to play with them. customer used them to replace alto mobile and audio control pieces
-------------------- One 220 amp alt, soon to be a 240 adj regulated One 15" sub 2000 watts 2 batteries an unfinished wall and a 150
06 Meca finalist M1 Posts: 579 | From: IN | Registered: Nov 2004
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Audio control will not be flexible enough. You will want time alighnment. Before you ever get to EQ you will use, crossover points, phase control and time alignment to smooth out the frequency response. EQ will be last.
The Audison will work great from what I've seen.
I havent played withe Arc piece. No idea what it does, but Fred Lynch of Arc has the Audison piece in his car, so that tells me it is more flexible. I will look at the Arc piece though.
posted
If you choose an EQ that does not come with time alignment (such as the Audio Control DQXS) you can get a head unit that utilizes it... Kenwood makes a few. It's all about the total package not just this or that component.
-------------------- 100% of life is not what you have, but rather what you do with it. The will to win is not enough, one must posses the will to prepare to beat the best. There is no such thing as luck. Posts: 17 | From: Roanoke, VA | Registered: Jul 2008
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posted
And to Mr. Jones I would like to inquire about the offer to smooth out the RTA curve... I will be in TN for about 6 months starting in May and am very interested in this format.
-------------------- 100% of life is not what you have, but rather what you do with it. The will to win is not enough, one must posses the will to prepare to beat the best. There is no such thing as luck. Posts: 17 | From: Roanoke, VA | Registered: Jul 2008
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posted
^the only problem with using a HU and a processor is that you have to go to 2 different places to get stuff done. it works, but is cumbersome.
I would really stick to an all in one unit. The 701 can be had for around $400. That isn't bad at all. The DSP 6 is going to be more. The Bit One is also around $400 I believe.
Let me know when you are in Tennessee and we can meet up somewhere. If you have a termlab with the RTA bring it. If you don't I'll bring my Audio Control and my TrueRTA (I will have it by then). Those two combined should get you close, but having the actual termlab RTA will be needed to nail it.
posted
AWESOME!!! er, Andy . I will keep in contact for sure. Thanks.
-------------------- 100% of life is not what you have, but rather what you do with it. The will to win is not enough, one must posses the will to prepare to beat the best. There is no such thing as luck. Posts: 17 | From: Roanoke, VA | Registered: Jul 2008
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