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Discussion Starter · #1 ·
CDT ES-02 "Tweeters" (250-20kHz)
Rainbow Sound line 6.5" Midbass' (50-4250Hz)
Ported 12W6v2
No rear fill
Fully active w/ a BitTen D
50W per front driver, 500W to Sub (Alpine MRP)

Tweeters are mounted in on axis pvc end caps where the dash and A-pillars meet, mids off axis low in the doors.

Ive been playing around with different crossover points with this setup for a while and just can't seem to get it right, especially in the mid bass department. If i recall correctly I've got highs crossed at 600Hz 24db Linkwitz, mids from 80-1000Hz 24db Butterworth, sub at 80Hz 24db Butterworth.

Any suggestions/advice to achieve better blending and imaging I'm all ears!

Thanks in advance
 

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Why doesn't it sound right? Too harsh, not enough mid bass or highs or sub? I think your right it just sounds like a tuning issue. How have you tuned it? Did you use a oscope or a Rta? 600hz seems odd crossover point for the highs, very low, if that's the tweeters you are talking about then up towards 2-3-4k would be more suitable. I'd try crossing the mids a wee bit lower 70-60 hz. To get better imaging try a steeper slope on the transition between the mids and tweeters. It would sound like you have a huge issue with the mids and tweets since the tweeters are that low.
If you have access to a Rta I'd highly recommend looking at the Rta to give you a look at what the speaker is doing and where it dips/peaks. Use a pink noise track with a mic, if u can.
 

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Discussion Starter · #3 ·
Why doesn't it sound right? Too harsh, not enough mid bass or highs or sub? I think your right it just sounds like a tuning issue. How have you tuned it? Did you use a oscope or a Rta? 600hz seems odd crossover point for the highs, very low, if that's the tweeters you are talking about then up towards 2-3-4k would be more suitable. I'd try crossing the mids a wee bit lower 70-60 hz. To get better imaging try a steeper slope on the transition between the mids and tweeters. It would sound like you have a huge issue with the mids and tweets since the tweeters are that low.
If you have access to a Rta I'd highly recommend looking at the Rta to give you a look at what the speaker is doing and where it dips/peaks. Use a pink noise track with a mic, if u can.
Sorry, should have went into more detail on this since its such a broad question. I used a RTA to tune it a few times, i managed to get it fairly flat too, which I think is the strange part. 24db is the steepest slope available to me through the BitTen. The reason I have the highs crossed so low is because I am trying out those wideband tweeters/midranges from CDT that can even go down to 250Hz. Im having a hard time blending the midrange with midbass if that makes sense, I usually end up concluding with a need for more midbass response. Im sealing up my doors tomorrow so that should help a little bit i would think. Im suspecting my time alignment could use some tweaking as well.

Im also unhappy with how my sub blends with the mid bass. I can't seem to get that even close to how i think it should be.

Im chalking all this up mostly to user error on my part haha
 

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Sealing the doors should make a huge difference in midbass, that should help with blending the sub. Since you are using 6.5 mids and not larger woofers like 8" or 10" you shouldn't expect them to be real beasts below 80Hz or so, let the subwoofer handle that stuff. I'd also raise the crossover on the "tweeters" even though the are widebanders I'd try with a HPF of about 1,000Hz.
 

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Discussion Starter · #5 ·
Sealing the doors should make a huge difference in midbass, that should help with blending the sub. Since you are using 6.5 mids and not larger woofers like 8" or 10" you shouldn't expect them to be real beasts below 80Hz or so, let the subwoofer handle that stuff. I'd also raise the crossover on the "tweeters" even though the are widebanders I'd try with a HPF of about 1,000Hz.
Sounds good to me, Ill change them after I finish the doors and post back.
Thanks
 

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Yeah it sounds like a tuning issue. Firstly, since you have access to a Rta that should help lots. Check your deck for distortion and flatten everything out, 0 bass boost/treble etc. then double check your gains on your amp(s) too.
Now I think you will need to re-assess your crossover points, you should get a pink noise track and play it with a mic in the car (drivers seat headrest usually) this will be testing your frequency response. Use the RTA with the pink noise track. This step is crucial to making a system sound really good.
So study the Rta and write down any dips or peaks on each driver. You will optimally find what frequencies the speaker will play the most efficiently without any dips/peaks etc.
Then set your crossover points for your filters on the bit ten, a good starting point is 80 hertz for the LPF And around 3k HPF or so for the tweeters. What will dictate this, is what you find with the RTA and pink noise first, where the speaker plays the best (frequencies).
Then eq it. Try to flatten out the signal, DON'T boost any frequency if you have a big peak. Try to get it sounding a bit better with the first tune, then analyse it again and then go back to the Rta and re EQ it. You could take up to 3+ tunes to get it sound perfect. The bit ten has the ability to make it sound realy good if your install and crossover points are correct.
Try not to over or under Lap the crossover points too much, I would try a lower LPF around 60 hz. I'd keep with 24db slope to keep it safe as that's the steepest the bit ten allows.
Do you know the fs of the tweeters? Usually have your hpf one octave above the fs of the tweeter, I'd go 3k to stay safe.
So get your crossover points correct first, then eq it 2+ times.
 

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Discussion Starter · #8 ·
Yeah it sounds like a tuning issue. Firstly, since you have access to a Rta that should help lots. Check your deck for distortion and flatten everything out, 0 bass boost/treble etc. then double check your gains on your amp(s) too.
Now I think you will need to re-assess your crossover points, you should get a pink noise track and play it with a mic in the car (drivers seat headrest usually) this will be testing your frequency response. Use the RTA with the pink noise track. This step is crucial to making a system sound really good.
So study the Rta and write down any dips or peaks on each driver. You will optimally find what frequencies the speaker will play the most efficiently without any dips/peaks etc.
Then set your crossover points for your filters on the bit ten, a good starting point is 80 hertz for the LPF And around 3k HPF or so for the tweeters. What will dictate this, is what you find with the RTA and pink noise first, where the speaker plays the best (frequencies).
Then eq it. Try to flatten out the signal, DON'T boost any frequency if you have a big peak. Try to get it sounding a bit better with the first tune, then analyse it again and then go back to the Rta and re EQ it. You could take up to 3+ tunes to get it sound perfect. The bit ten has the ability to make it sound realy good if your install and crossover points are correct.
Try not to over or under Lap the crossover points too much, I would try a lower LPF around 60 hz. I'd keep with 24db slope to keep it safe as that's the steepest the bit ten allows.
Do you know the fs of the tweeters? Usually have your hpf one octave above the fs of the tweeter, I'd go 3k to stay safe.
So get your crossover points correct first, then eq it 2+ times.
My source is digitally connected to my bit so no distortion there :) and my gains are set using a SMD DD-1. I have a pink noise generator on my phone that I use for rta along with truerta and a measurement mic in the drivers headrest. So good to know I'm doing that part right haha. I'll retune it tomorrow and find the parameters of my tweeters and mids to see if I can dial in some good crossover points, then EQ a couple more times. I'll also redo my TA and correct any phase issues/level match if need be. Didn't know about the fs in relation to hpf point. Thanks!
 

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Discussion Starter · #10 ·
"Fairly flat"... with RTA/pink noise?

You don't want that. Lows should be at least +10dB with rolloff to "0dB" at 160-200Hz, at ~1kHz you want a ~3dB/oct rolloff to 20kHz (or so).

Sent from my Samsung Galaxy 3 via Tapatalk.
Interesting, I've always just gone for a flat response with the idea that would sound the most accurate
 

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"Fairly flat"... with RTA/pink noise?

You don't want that. Lows should be at least +10dB with rolloff to "0dB" at 160-200Hz, at ~1kHz you want a ~3dB/oct rolloff to 20kHz (or so).

Sent from my Samsung Galaxy 3 via Tapatalk.
Yeah it all depends on the tune. I don't have heaps of tuning experience but know quite a bit and know because I've done it wrong before and know how to tune well. I usually try to get it flat (ish). I fix any peaks by only cutting peaks/dips to flatten it out. Then tighten up the eq curve to what sounds good, then eq it to boost the sub range and roll it off to the mid. The hardest part is around the 1-6khz range because it's the most sensitive noticeable range to music. Everyone is different though, when I tuned someone's system I didn't boost much when I eqed and changed it slightly from there. And it's important not to over EQ. other wise you could [email protected] your tune, I I write down my first tune and the frequency response results.
 

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I have a similar setup w/ tweeters on axis and have spent a countless amount time getting everything to blend well considering I don't have a RTA to take full advantage of the Bit One EQ
What I can say is that time alignment is key
So far this is where i'm at...

Substage: 80hz @ 18db
Midrange: 80hz-2500hz @18db
Tweeters: 2500hz-20,000hz @24db

Hope that helps a little
 

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Rta Flat, is flat out wrong. It's one of the biggest car audio myths. Do you want it to measure right or sound right? It's your choice.
 

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Rta Flat, is flat out wrong. It's one of the biggest car audio myths. Do you want it to measure right or sound right? It's your choice.
Yes ^^

RTA flat using pink noise is not "accurate". The response must be tilted downwards in order to get it to sound somewhat balanced in a car...

Sent from my Samsung Galaxy 3 via Tapatalk.
 

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Interesting, I've always just gone for a flat response with the idea that would sound the most accurate
Right, I have done it both ways. RTA flat tune to start out, then adjust to my liking. After measuring again I end up with something like Hanatsu is describing. So about a month ago I decided to do it his way and I haven't looked back. Right now I am playing on the steepness of the roll off, Hanatsu's roll off is a bit too steep for my taste so my tuning is a little less steep. There is another thread where this is discussed in more details and RTA curves you can use as a reference.

Also, I do not like to have too much overlap between crossover points (signal summimg = more EQ) and I prefer to crossover my tweeters much higher than the way you have them (2.5k).
 

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you should have aprox 20 db decrease from 20Hz to 20kHz on RTA.
Try to use 12 dB/oct filter slope for midbass lowpass and the same slope for high pass for tweets and if possible not lower than 4-5kHz. Usually it is hard to get exelent blending between drivers with steep slopes if drivers dont match quite good.
 

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Discussion Starter · #18 ·
I have a similar setup w/ tweeters on axis and have spent a countless amount time getting everything to blend well considering I don't have a RTA to take full advantage of the Bit One EQ
What I can say is that time alignment is key
So far this is where i'm at...

Substage: 80hz @ 18db
Midrange: 80hz-2500hz @18db
Tweeters: 2500hz-20,000hz @24db

Hope that helps a little
Thanks! I don't have a "real" RTA so i kinda set up my own. Download TrueRTA and buy a measurement mic and your set for way less than a real RTA setup.
 

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Discussion Starter · #19 ·
Rta Flat, is flat out wrong. It's one of the biggest car audio myths. Do you want it to measure right or sound right? It's your choice.
When you put it that way, i feel like an idiot haha that makes sense.

you should have aprox 20 db decrease from 20Hz to 20kHz on RTA.
Try to use 12 dB/oct filter slope for midbass lowpass and the same slope for high pass for tweets and if possible not lower than 4-5kHz. Usually it is hard to get exelent blending between drivers with steep slopes if drivers dont match quite good.
So a shallow slope could potentially blend the two together better at a higher high pass point? Ill try that too, good to know because these drivers for sure do not match haha.
 

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Here are some things for you to try.

1. The sub to mid xover at 80 is ok for now. Cross the mid and tweet ~ 3khz. Try both at 12db/oct and 24db/oct, see which sounds better.

2. If you had setup a flattish overall response, that will change once you change the xover points. Measure and try to flatten it out again. Now play the pink noise tracks from 400hz to 5khz. Since it measures flat they should all sound about equally loud, right? Listen to them, do they sound equally loud to you?
 
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