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2011 Evora NA 6sp
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Discussion Starter #1
So I have this fancy radio n I have no clue how to use it. I'm not a crazy audio person(hell, I just installed the factory amp n sub n it actually works) just wanna know what to set to to have good sound and not blow the amp up
1257092
1257093


It's a kenwood dmx905s
Alpine 6.5" r speakers
Stock sub and amp

Thanks.
 

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He's on fire!
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I do not have an evora but...

Set the equalizer however you like the sound. Any head unit should have presets so you don't have to tune each band.

Generally speaking you probably want a HPF threshold of 80 - 100hz for those alpine speakers. Typically you try and set it as low as you can for a "max" listening volume- ie if you turn up the volume and the speakers crash out with a HPF of 80 hz, try 100hz.

You set your LPF of the sub to be the same frequency as the HPF for your fronts.

You can treat the "gain" like a spike in the EQ graph- if you find you've maxed out the 62.5 bar, want more bass, and your subwoofer can support it, increase the gain on the sub (and probably lower the EQ boost for 62.5)
 
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Well I (famously?) have an Evora and I contend I am smart about audio. If I'm honest, I'll admit only that I was smart enough to make a living at it....there are plenty smarter, especially when it comes to 12V but I can tell you the general rules of eq and X-over set up.

First about EQ: It is generally considered good practice to use your filters in cut mode only (for system tuning) for a variety of reasons. I will defend this comment if necessary but if you will grant that to me, I can tell you where I'd take it from there. A caveat is that as long as you leave the stock speakers as they are whatever you do with the head end is going to be as much or more about what feature set you have as making big improvements in sound quality.

I use eq to help control resonances inherent in the system and to make, to the extent possible, the response where I am sitting as smooth as possible. Best tune is technically possible in only one spot. There is little possibility to actually create objectively measurable flat/accurate sound in the Evora but it can be improved or worsened according to set up.

Remember in boosting any given frequencies (and more so at the extremes) that you are demanding more power in direct proportion to how much boost you add. That's one of the reasons why it's important to be judicious in adding boost. There are others, including sound degradation due to the way filters interact.

So the lesson is to use as little eq as you need to get the job done and typically it's best and easiest to pull down peaks rather than boost holes in the reponse curve. If you wanted to really get into this there are a number of measurement programs you can load on a tablet or phone (I find iOS the better platform) for cheap or free but using them to advantage requires some understanding of how it all works.

The advice you got about selecting crossover frequencies is correct. Selecting exactly where to cross over is an experience thing (and dependent on speaker parameters as well) but can be done by cut and try. I think keeping the crossover legs symmetrical as described by Mr. ads above is a good starting point and is usual practice anyway for electronic crossovers.

I could say more (or could have said less) but tuning a system is a mix of understanding the basics (means you have to get into it a bit) coupled with experience and knowing what good sound is.....or what you think good sound is. I prefer to think there is "better sound" and "worse sound" but even among experts there are preferences for what sounds balanced to the individual and what qualities one seeks: clarity (intelligibility), balance and transparency vs. texture, impact and tone. It's hard to pull it all together, especially in a car. Although I'm comfortable tuning relatively complex systems and have 40 years in professional audio I find car audio offers challenges that other 'venues' don't and I have heard far more abortions (by my reckoning) than good executions in car audio, including many upgraded factory systems.

Opinions offered here by me or anybody else are usually worth what you pay for them, but since discussion is free I suggest you experiment within the broad parameters I just laid out and we can talk about your results. Others will provide better info on actual 12V practice but I've got a reasonable understanding of the electro-acoustics involved.

Or so I claim.
 

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2011 Evora NA 6sp
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Discussion Starter #4
Think you just melted my brain. I messed around with the settings I think it sounds ok. I pulled some EQ settings from a post that apparently lotus wants you to set with the stock unit. Don't know how good it is with the upgrades speakers.

My biggest concern is blowing out the stock subwoofer or killing the amp(since apparently they are known to?). I'll take pictures hopefully Monday or Tuesday of what it's set to.
 

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Acme Super Moderator ** The Enforcer **
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I'll explain what an equalizer is for, without getting too technical.

First of all, all speaker systems (and listening environments) have frequencies that are louder or softer than what is perfectly "flat". An equalizer can be used to produce a flatter response across the spectrum of frequencies for both a speaker system and a listening environment. A good equalizer with a pink noise generator, a lab-grade microphone and frequency spectrum display can be used to "tune" both the speaker system and listening area to achieve a fairly flat response across the spectrum of frequencies. We'll get into pink noise in a minute, but for now I'll keep this simple.

The problem with the above scenario is that if we tune the speaker system and listening room to be flat at a certain volume level, it doesn't remain flat at a higher or lower volume, at least to our ears. Our ears perceive different frequencies differently, and then change additionally (on top of that) at different volume levels. This is denoted in an equal-loudness curve, which I'll add a link to below. This is why we use pink noise to tune our speaker system and listening area, as pink noise is all frequencies generated at a level that will appear flat to our ears using the Fletcher-Munson curve (superseded by more modern curves).

So, when listening to low volume sound, our ears tend to not hear low and high frequencies as easily. This is why you have a loudness button, just for low volume compensation, and where you don't have an equalizer to do the job more eloquently. At low volume levels the equalizer curve tends to resemble a sine wave, where at higher volume levels the equalizer curve tends to be flatter. Then of course the equalizer curve also has peaks and valleys for the speaker system and listening area. All speaker systems and listening areas will be different, unless we're using an anechoic chamber, used for testing speaker systems, missiles, fighter jets and a lot of other things.

One last thing. Perfectly flat systems don't always sound good. They're certainly better than an untuned system, but they need a little warmth, and that's a personal thing. A good sound engineer can really make a huge difference. Alan Parsons is not only a musician, he's a very good sound engineer. Good sound engineers make "clean" music, no matter the genre. Ideally, I like my equalizer at the optimum listening point, so I can adjust it as necessary. I used to have mine built below my coffee table where I could adjust it from my couch.

I hope this helps while staying simple. Audio gets very complex fast, just like almost anything else. The more you know, the more you realize how little you know.




San
 

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Think you just melted my brain. I messed around with the settings I think it sounds ok. I pulled some EQ settings from a post that apparently lotus wants you to set with the stock unit. Don't know how good it is with the upgrades speakers.

My biggest concern is blowing out the stock subwoofer or killing the amp(since apparently they are known to?). I'll take pictures hopefully Monday or Tuesday of what it's set to.

If you are satisfied with the sound and have not reduced the speakers to ash, that's a fine start. I am mostly interested in convincing you how to adjust your system safely. The audible results you achieve are another story. I'll just try to keep you safe from worry. I'll also try to make something relatively complex into something simple. I will likely fail!

Every time you boost a given part of the spectrum 3dB, you ask the amp to deliver twice the power in that region. Consequently you run out of juice rather quickly if you try to bring up the power in any given band by a significant amount. If you boost adjacent bands, there is another down side: the interaction of the filters (each band is a filter) will introduce additional distortions in the form of ringing and phase anomalies.

Above theory now turned to practice: Try to use the eq as a cut only device to the extent you can. It helps to visualize the response curve as a series of hills and valleys. Don't try to fill the valleys to get a flatter response. You can't anyway....phase cancellations ("negative" holes in the acoustic response caused by the space itself) are impossible to correct with boost. Instead, remove the excess energy from the hills.

What oldmansan is telling you is that shooting for a perfectly flat response (impossible in practice anyway) doesn't necessarily result in the best listening experience. The phenomena he mentions regarding how we hear frequency extremes is called the "Fletcher Munson Equal Loudness Curve" in the trade. Let's spare you that part of the discussion and simply suggest that you use boost moderately and use cut to make the larger adjustments wherever possible. You may wish to make your adjustments at a level that you will actually be listening to in the car. In the trade, eq adjustments for room response are typically made at a specific reference level (often referenced to 1kHz...sort of midband. By being judicious with boost, you will reduce your power requirements at the extremes thus reducing the chance you'll drive the system into distortion which will reduce or eliminate the possibility of frying your transducers (speakers). Again, explanations upon request.

Theory reduced to practice:
Make small adjustments to start. Do not drive the system into audible distortion and try to avoid significant boosting in the bass/treble regions. BTW the plot you have put up shows exactly the sort of curve you typically don't want to equalize to. If you hear the rig starting to sound bright/piercing in the high end and/or producing unusual noises in the low end, (clacking, flapping, quacking noise or other nasties) you must back off the level. This level of distortion means the amp is trying to deliver more energy than it has to give. This tends to flatten the waveform at the clipping point (where the amp runs out of steam). Clipping produces a ton of dirty energy (distortion) that WILL blow your speakers, even if the amp is technically incapable of producing the rated power handling of the speaker.

The topic is complex enough to make getting somebody up to speed about how this is properly done impossible to accomplish in short order on a car forum!! There are a lot of specialized physics to get your arms around so Lesson Number 1 is: Feel free to experiment, don't feel free to allow the system to go into distortion (clipping). That should keep you safe for now.

Wish you were here, system alignment a specialty.:).
 
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