Poor SQ

Ishouldbeworkin

My current setup does not sound as good as I feel it should on paper and I don’t know where I should continue my work to improve it.

My current setup:

Eclipse CD7200 MKII HU with 6 outputs that I have going separately into an AudioControl DQS (6 channel equalizer). From there, the highs and mids go into my amplifier (PA 500.4) which is powering my SR 5250’s (not using the crossovers that came with the package). My currently set HU crossover points , if I am remembering correctly,are around 5khz for the tweets /mids, and 50Hz for the mid/sub, though I will have to check what slopes I have them set at currently since I have messed with it a lot.

The tweeters and mids are located in the stock speaker locations in my 2003 G35 coupe. The SR 124DVC, which is located in the trunk, is powered by a PA 1200.1.

I will admit that I do not have well trained ears that can easily pick out exactly what the problems are, so I am basing the “poor sound” only on my feeling that it just isn’t that great. It really is not consistent in the ability to reproduce good sound from one artist to the next or one type of music to the next. I don’t think I should have to adjust bass/mid tweet/ levels for each song I want to play. Is it just wishful thinking to want to be able to put any CD I have in and have it sound naturally good, lol? I think that this issue should be addressed before worrying about other more technical things like imaging etc.

Additional notes: Prior to the install, I took over my friend's garage for a week and put as much sound dampening and insulation as I could stand (read “afford”) inside the whole car. The equipment install was done by a local car audio shop that I will not name because if I think too much about them I will get angry. I corrected the problems that they caused that were within my ability to fix and left it alone for quite some time because I was just fed-up with the situation.

I currently do not have a garage to work in and since I might lose my PhD funding in my 4th year, I don’t want to try any fixes which are expensive. Unfortunately, this college town is not really big on car audio and I don’t know where to go for good advice, or a good ear.

arun1963

Ishouldbeworkin wrote: »

My current setup does not sound as good as I feel it should on paper and I don’t know where I should continue my work to improve it.

The tweeters and mids are located in the stock speaker locations in my 2003 G35 coupe. The SR 124DVC, which is located in the trunk, is powered by a PA 1200.1.

What are the stock locations? Just curious for down the line.

Ishouldbeworkin wrote: »

I will admit that I do not have well trained ears that can easily pick out exactly what the problems are, so I am basing the “poor sound” only on my feeling that it just isn’t that great. It really is not consistent in the ability to reproduce good sound from one artist to the next or one type of music to the next. I don’t think I should have to adjust bass/mid tweet/ levels for each song I want to play. Is it just wishful thinking to want to be able to put any CD I have in and have it sound naturally good, lol? I think that this issue should be addressed before worrying about other more technical things like imaging etc.

As Dskip pointed out, cd's are recorded at different levels and with varying skill levels. However if you leave aside the really crappy recordings and assuming your setup is installed and tuned well, you should be able to go from cd to cd without requiring any major changes. A tweak here or there is always on though.

Ishouldbeworkin wrote: »

Additional notes: Prior to the install, I took over my friend's garage for a week and put as much sound dampening and insulation as I could stand (read “afford”) inside the whole car. The equipment install was done by a local car audio shop that I will not name because if I think too much about them I will get angry. I corrected the problems that they caused that were within my ability to fix and left it alone for quite some time because I was just fed-up with the situation.

Sounds like some install issues. We may have to go thru this issue step by step to check everything. The shop may have made a boo boo somewhere that you may not have caught.......and hence its still there and impacting your sound

Ishouldbeworkin wrote: »

I currently do not have a garage to work in and since I might lose my PhD funding in my 4th year, I don’t want to try any fixes which are expensive. Unfortunately, this college town is not really big on car audio and I don’t know where to go for good advice, or a good ear.

The one thing you will not need is to buy anything else. You have a great setp. We just need to run thru the install once and then get down to tuning. You won't be spending more money but you may have to devote a fair bit of time to get things right.

Can you post some pics of your install, door panels off would help. Are the speakers mounted securely, is the polarity of the connections good?

Pls make a note and share all your current settings. Gains, all amp settings, xover points and slopes, TA settings, eq settings....the whole lot. The basic idea is to first check your install and basic settings and then set the drivers in phase and achieve Left / Right balance for as many frequencies as you control.

http://www.polkaudio.com/forums/showthread.php?t=92872

http://www.polkaudio.com/forums/showthread.php?t=72504

http://www.polkaudio.com/forums/showthread.php?t=95557

Some threads that you may want to go through. Welcome to CP.

Ishouldbeworkin

First, thanks DSkip and arun1963 for your responses.

DSkip:
I dropped the crossover point on the tweets down to 4 kHz (@24db/octave) to start at the same reference point. With such a high slope, should both the mid’s high cutoff be at the same frequency and slope? The speakers have just over a year of time on them, which includes several long drives, so they should be well past the break-in period. I have no clue as to the actual number of hours, but a lot.

arun1963:

I attached an image showing the stock tweeter location.

(1) As you can probably see (if attaching it worked), the driver side tweeter location is only about 6-8 inches from the cover over the instrument panel, which is very early in the path of the tweeter. The location of the tweet on the passenger side is identical without that same instrument panel obstruction. (I know this is most likely the 1st of several installation problems, but I wonder if this is something that will require too much compensation and should be changed before continuing…)

(2) Settings:
Crossover Points (set from HU): (high/mid) 4kHz @ 24db/octave
(mid/bass) 63Hz @ 18db/octave.
I am not sure how much overlap I should have in the crossover points so they are set the same to start.

TA Settings(ms): LH 1.72 RH 0.30 LM 1.20 RM 0.00

For the TA settings I used the formula suggested by my HU owner’s manual, which was:
A = (B-C)/34
A: Time delay (ms) B: Distance to furthest speaker(cm) C: Distance to speaker to be adjusted

( these settings are ignorant of the tweeter obstruction noted in (1) but I am unsure how to correctly compensate, so I am using the suggested TD settings as a baseline)

EQ Settings:
Here I wiped the slate clean today and set all EQ settings to zero, with all frequencies neither boosted nor attenuated.

Gain Settings: I am unsure how to measure/answer this point (“noobness” showing). Initially, when I was setting up my levels, I achieved the least noise or hiss with higher output settings from my HU and low gains from my amplifiers.

One thing strange that I noted was that the input level meter still barely reads any signal. I understand that most head units overrate their output voltage, but this head unit is supposed to have 8V pre outs.
Additionally, I had to change some jumpers inside the EQ to get rid of some bad engine noise I had just after the initial install.
There is also still an audible pop (not loud, but it’s there) when I turn the key and the system gets power as well as a very high pitched very dim oscillating sound that I can notice when the car is off( I ejected the CD and the sound remained. Pictures with the door panels off are still to come.

arun1963

Thats a common, stock location for the tweet. Remove the door panel and see if you can angle the tweets to fire up and forward a bit. There's a mounting ring that comes with the set, which allows you to do this.

The sub/mid xover point is ok for now. We'll try 50 later. For now, just put the sub on the steepest slope you have, e.g. 36db/oct. Put the mid on 24db/oct. You don't need overlap at the xover point.

One of the threads I linked earlier has a post on time aligning. Try it that way and see where you get to. Getting your speakers in phase is the first big jump. You will hear a big improvement in sq.

Can you set your eq separately for left and right channels? How many and which frequencies do you control?

Set the amp gains at around 10 o'clock. Keep the gains low. On both the 500.4 and 1200.1. I assume that you're running the sub at a 2ohm load.

You lost me on the 'input level meter' bit. What are you referring to?

Ishouldbeworkin

I am more than willing to admit the install is poor. I should have gone with my gut feeling and not let the place touch my equipment at the time, but I was too eager to hear the system and there was not a lot of places to choose from. I tried to help them by making line drawings of the installation connections so that there would be no confusion in what I wanted done.

I still ended up with them **** up basic things. I have a 4 channel amp for my highs/mids (PA 500.4), which they used the 2 channel instead of 4 channel setting for so they didn't realize they had the mid-range output going to the tweeters. Once i got home and tried to figure out what they did and I switched the amplifier to 4-channel, it was immediately apparent that they had reversed the wiring. Sure, it was only a matter of switching some cables but come on. They just told me it seems a lot of mids are playing though the tweets so I shouldn't turn it up until I adjust the EQ. I honestly blame myself a lot for it. Before I rant more, I had better take a break.

Btw....I am in Gainesville, FL...( about 5 hours from Atlanta and 5 hours from Miami if you only know big cities around north Florida. )

Ishouldbeworkin

arun1963 wrote: »

Thats a common, stock location for the tweet. Remove the door panel and see if you can angle the tweets to fire up and forward a bit. There's a mounting ring that comes with the set, which allows you to do this.

The sub/mid xover point is ok for now. We'll try 50 later. For now, just put the sub on the steepest slope you have, e.g. 36db/oct. Put the mid on 24db/oct. You don't need overlap at the xover point.

One of the threads I linked earlier has a post on time aligning. Try it that way and see where you get to. Getting your speakers in phase is the first big jump. You will hear a big improvement in sq.

Can you set your eq separately for left and right channels? How many and which frequencies do you control?

Set the amp gains at around 10 o'clock. Keep the gains low. On both the 500.4 and 1200.1. I assume that you're running the sub at a 2ohm load.

You lost me on the 'input level meter' bit. What are you referring to?

(1) I found an interesting post somewhere about a decent looking way to fabricate some speaker pods that looks doable. I am going to go ahead and at least paint and prepare them and see how they would look installed in my car before removing the tweets from their current locations. I am not sure how much of my adjustments will be messed up if the tweets will be moved.

(2) All slopes set to 24db/oct now.

(3) I am trying to work on the time alignment now. I used the baseline from the HU manual calculation, but as i adjust it, it is really difficult to tell the difference. ( It's like being at the optometrist and having him ask me which one's better ..this one?...this one?... they all look the same...but I sure as heck know when i put on the wrong pair of glasses. ) Perhaps there is a particular track/song that will make this easier to judge (say on the Chesky ultimate demonstration disk).

(4) Yes, I can eq separately for each speaker/channel. I am using the 6 outputs for my HU into the 6 inputs of the EQ.. which has 30 graphic equalization controls per channel. (althouggh i don't have to buy any new gear the wired remote to control the eq settings would be really nice for tuning...will stink to have to go to the trunk for every change ). On the good side though, I got a digital sound level meter 20 bucks cheaper than they listed online at "the shack" today:)

(5) the amp gains are both low, though I cant recall what they are at at the moment.

(6) I checked the driver's side door today and did a little more sound deadening at my friends house (his wife was gone for two days and he was allowed to play) and (also borrowed his camera) took some photos of it when he emails them to me.

arun1963

Ishouldbeworkin wrote: »

(1) I found an interesting post somewhere about a decent looking way to fabricate some speaker pods that looks doable. I am going to go ahead and at least paint and prepare them and see how they would look installed in my car before removing the tweets from their current locations. I am not sure how much of my adjustments will be messed up if the tweets will be moved..

Getting the tweets out of the sail panels and in pods on your dash, would give you the flexibility to play with the angles and axis.

Ishouldbeworkin wrote: »

(2) All slopes set to 24db/oct now.

Set you sub slope steeper if you can.

Ishouldbeworkin wrote: »

(3) I am trying to work on the time alignment now.........

You will find thousands of threads, across many forums, where this issue is hotly debated. There will be all sorts of calculations and scientific terms flying around that require an advanced understanding of physics and maths. Don't get caught up in all that junk. The fact that tens of thousands of people are hotly debating hunderds of theories, just means that none of them really works. Just remember you will never measure your way to good sound. You have to 'hear' your way there, while using all the tuning features at hand.

Time alignment is just another tuning feature, which you have to set by ear. The key to tuning is understanding how a feature (TA, Eq, xover point, slopes etc) works and then training your ear to use it properly. Perhaps the first step to tuning is just to listen to a good 2ch setup so your ears understand the concept of tonality, stage, image, height etc. However, thats a seperate exercise.

TA is basically ensuring that sound from speakers at different physical distances arrive at your ears at the same time. When this happens your brain locates the sound as coming from the front. Hence when you have set TA correctly it will feel like the sound is coming from the front, from your windshield. TA also allows you to set the sequence in which you hear the lows, mids and highs. Ideally, you want to hear the lows a fraction before you her the mids together, followed by the tweets together. Your brain derives height cues above 2khz. Hence, having the 2khz+ range physically higher (Dash/A-pillar mount, plus angling) and hearing it last, tricks the brain into thinking that the entire sound is from that height.

Let's set your TA by ear. Set your sub to 0. Now cut all drivers except your sub and the far mid. Delay your far mid till you hear the sub bass pouring out of your far mid. NOTE you should hear the sub bass while maintaining clarity in mid bass and mid range. You also want the sound at more or less dash level if not higher. The further you delay the mid, the higher you will percieve the sound location. BUT you will start losing sub bass presence. You want to hit the point where you have all three, clarity in all three ranges, height and sub bass presence. Delay the far mid to about 4.5ms, now play around in the 4.5-5.25ms range. Lets say that you set 5ms as the ideal point.

Now, cut the sub and play only your L&R mid range drivers. Keeping your far side value fixed at 5ms delay your near side driver to within 0.7-1.25ms of the far side delay. I.E. the range to play around in for the near mid would be 3.25-3.8ms. When you have the two mids in phase, you will hear the sound from the front as opposed to hearing it from your drivers. Also ensure that height from which youre hearing the sound is level across left and right side. Hence if the sound is higher(height) at the far side add more delay to the near mid. If its higher at the near side, reduce the delay on the near mid. Lets say you settle on a delay of 3.5ms for the near mid.

Hence the delay between the two mids is 1ms, 4.5ms-3.5ms. Now, set your far side tweet at 3.5ms and the near side tweet to 2.5ms. You're done with TA for now. As you get comfortable with the tuning functions you will learn to use them all together. TA is just another tuning feature. As you tweak the other features, so too for TA. Don't over complicate it.


I will come back to your points 4-6 later this evening. Try the TA bit, I would really like to hear your feedback once you have played with it a bit as suggested.

arun1963

arun1963 wrote: »

Hence the delay between the two mids is 1ms, 5ms-3.5=1.5msms. Now, set your far side tweet at 3.5ms and the near side tweet to 2ms.

Corrections in red.

arun1963

Ishouldbeworkin wrote: »

(4) Yes, I can eq separately for each speaker/channel. I am using the 6 outputs for my HU into the 6 inputs of the EQ.. which has 30 graphic equalization controls per channel. (althouggh i don't have to buy any new gear the wired remote to control the eq settings would be really nice for tuning...will stink to have to go to the trunk for every change ). On the good side though, I got a digital sound level meter 20 bucks cheaper than they listed online at "the shack" today:)

+1 for the remote. You're going to go nuts without it. The 31 frequencies are great. I'm wondering though, if this setup just fell into place, or if it was carefully put together for a purpose .

When you set your eq, with the test tones, this is one way you can go about it. Set eq at 0 for L/R at all frequencies. Play the tones for left side first and note the db reading for all frequencies. Then do it for the right side. First balance each frequency for left right and then level match across mid bass, midrange, upper mids and highs.

Ishouldbeworkin wrote: »

5) the amp gains are both low, though I cant recall what they are at at the moment.

Keep these around 10 o'clock.

MacLeod

Actually those SR5250's can go up to 5 KHz. Try that and see if it makes any difference.

To set the time alignment, dial in an AM talk radio station (AM is mono, thats what you want) and turn off the tweeters. Listen to the voice and add delay to the left speaker until the voice centers up. Turn off the mids and the tweeters on then do the same thing with the tweeter channels delay. If you get the Chesky disc, I use Track #1 for this. Put it on repeat and dial it in.

24 db/oct is a good slope. Try 30 if you want to but going too steep makes the blending of the mid and tweet too unnatural.

You DEFINITELY need a CD with filtered pink noise in 1/3 octave intervals. Autosound 2000 disc has these or you can get one from here. Turn on the mids only and play the test tracks on left side only then right side only and boost or cut as needed to get these leveled out. Then turn on the tweeters only and do the same. Getting things properly level matched is super important to getting things sounding their best.

Ishouldbeworkin

arun1963 wrote: »

Let's set your TA by ear. Set your sub to 0. Now cut all drivers except your sub and the far mid. Delay your far mid till you hear the sub bass pouring out of your far mid. NOTE you should hear the sub bass while maintaining clarity in mid bass and mid range. You also want the sound at more or less dash level if not higher. The further you delay the mid, the higher you will percieve the sound location. BUT you will start losing sub bass presence. You want to hit the point where you have all three, clarity in all three ranges, height and sub bass presence. Delay the far mid to about 4.5ms, now play around in the 4.5-5.25ms range. Lets say that you set 5ms as the ideal point.

Now, cut the sub and play only your L&R mid range drivers. Keeping your far side value fixed at 5ms delay your near side driver to within 0.7-1.25ms of the far side delay. I.E. the range to play around in for the near mid would be 3.25-3.8ms. When you have the two mids in phase, you will hear the sound from the front as opposed to hearing it from your drivers. Also ensure that height from which youre hearing the sound is level across left and right side. Hence if the sound is higher(height) at the far side add more delay to the near mid. If its higher at the near side, reduce the delay on the near mid. Lets say you settle on a delay of 3.5ms for the near mid.

I tried messing around with the TA some today after I finished adding still more vibration dampening around the speaker mounts inside the doors. Anyhow, I was looking at what you had wrote and was curious why you were suggesting that the far mid have more delay than the near one...Wouldn't a further speaker already be delayed by the greater distance, so the near one should have the larger delay setting? ...or am I missing something?

Ishouldbeworkin

MacLeod wrote: »

Actually those SR5250's can go up to 5 KHz. Try that and see if it makes any difference.

To set the time alignment, dial in an AM talk radio station (AM is mono, thats what you want) and turn off the tweeters. Listen to the voice and add delay to the left speaker until the voice centers up. Turn off the mids and the tweeters on then do the same thing with the tweeter channels delay. If you get the Chesky disc, I use Track #1 for this. Put it on repeat and dial it in.

I got the Chesky disk from itunes and was wondering if the compression from itunes when burned directly to CD is the same as the store-bought version.

24 db/oct is a good slope. Try 30 if you want to but going too steep makes the blending of the mid and tweet too unnatural.

No real choice here for me, my HU's crossover maxes out at 24db/oct.

You DEFINITELY need a CD with filtered pink noise in 1/3 octave intervals. Autosound 2000 disc has these or you can get one from here. Turn on the mids only and play the test tracks on left side only then right side only and boost or cut as needed to get these leveled out. Then turn on the tweeters only and do the same. Getting things properly level matched is super important to getting things sounding their best.

I remember reading a post about SR tuning where you described using some tracks on a demonstration CD to get things to gel-up or something prior to level matching both sides. I don't know what I should be targeting during this process. For example, on Spanish Harlem, are you comparing it to the memory of the instrument/vocal relative levels that you know from some reference system, or is it just by feel?

MacLeod

Ishouldbeworkin wrote: »

I got the Chesky disk from itunes and was wondering if the compression from itunes when burned directly to CD is the same as the store-bought version.

Its probably not as good as the original CD but it doesnt matter cause you so long as you burned to an AUDIO CD and NOT MP3's and its a quality burner, you want hear a difference.

No real choice here for me, my HU's crossover maxes out at 24db/oct.

Thats fine. No need to go steeper than that anyway except maybe for the sub.

I remember reading a post about SR tuning where you described using some tracks on a demonstration CD to get things to gel-up or something prior to level matching both sides. I don't know what I should be targeting during this process. For example, on Spanish Harlem, are you comparing it to the memory of the instrument/vocal relative levels that you know from some reference system, or is it just by feel?

What I do is I put the 1st track on repeat and listen to it. Its simple a male narrator's voice. I set my EQ to control both left and right together then start at 63 Hz and turn it all the way up then all the way down and leave it where it sounds right. I move all the way up the band doing this. Ill go up to 1 octave above the crossover point on the mids and 1 octave below on the tweeters with the EQ'ing.

After I get his voice sounding right Ill go to Spanish Harlem. I use the first 3 notes of the standup bass but YOU SHOULD NOT! If you get these notes nice and smooth youll KILL any midbass and punch you have in rock or metal. Unless you listen to Jazz and clean acoustic music, keep the 3rd note in Harlem boomy. Listen to her voice adjust the EQ in the 315-2500 Hz range and dial it in some.

Next Ill go to Track 5 and listen to the trumpet. If it sounds like a kazoo, youre too hot in the upper midrange. Listen to her voice and dial in some more.

Track #9 has some good sub bass (20-31 Hz) and a good male voice. Tweak on this.

If you listen to rock and metal, go to Track #17 and dial in your midbass and sub bass. If you get this track rocking, youll be way to hot for the stand up bass tracks like 3 or 27 but youll be fine for "real world" listening.

After youve done this, then you level match. After youve level matched you go back thru and fine tune with the tracks I just listed.

After youre done, save this tune to a preset. Go in the house. Now the next day live with this tune while you drive around and pick out the things you dont like. That night try to fix those things. Once you go thru and fix what you think you didnt like, save that to a preset. Now compare them both. A/B them and see what you think.

This is an endless process by the way.

What I use is my ears. Ive been listening to every stinking detail of that CD for the 5 years Ive been competing in MECA so I know it inside and out and have heard it on a million different systems. If I were you Id hunt down or put together a quality home setup and use that as your reference. A lot of competitors invest in some high quality headphones and use that.

arun1963

MacLeod wrote: »

This is an endless process by the way..

and it can eat up a ton of mind space, even when youre not in the car.

MacLeod wrote: »

What I use is my ears. Ive been listening to every stinking detail of that CD for the 5 years Ive been competing in MECA so I know it inside and out and have heard it on a million different systems. If I were you Id hunt down or put together a quality home setup and use that as your reference. A lot of competitors invest in some high quality headphones and use that.

Damn, I wish the meca cd was available here. I use downloaded focal cd's. One of the cd's that has only music, has Spanish Harlem. The sr's really sing on that one. How about some of the special effects on the focal cd? I like the single stroke bike, drawing the circle and the bulb breaking.

Ishouldbeworkin wrote: »

I tried messing around with the TA some today after I finished adding still more vibration dampening around the speaker mounts inside the doors. Anyhow, I was looking at what you had wrote and was curious why you were suggesting that the far mid have more delay than the near one...Wouldn't a further speaker already be delayed by the greater distance, so the near one should have the larger delay setting? ...or am I missing something?

Saw your post, but things have been crazy all around.

Yes, the further the speaker the less you want to delay it. I had converted my settings in inches to ms. On my p-880, TA is in inches. You set the distance of each driver and the deck plays the furthest speaker first and the nearest, last. When you TA in ms, the hu plays the driver with the least time delay first and the one with most delay is played last. From my example, your near mid could be at 4.5ms and the far mid at 3.5ms. The tweets would be swapped too. The rest remains the same

That said, there is little or no correlation, between the settings that sound good and the actual measured distances. So none of the formulas are going to work. Just stop thinking about them and start listening to see if its working.

In my car the physical distance vs TA distance of the drivers is, far mid 48" actual/68" TA, near mid 32"/55", far tweet 45"/55", near tweet 28"/42" and the sub is at 62"/130" with phase reversed. When I tweak everything, I play with TA a bit too, but within an inch or two of these distances, moving all drivers together.

With TA, you're basically doing two things. Making sure your drivers fire in the correct sequence and getting your speakers in phase. Here, I get the drivers in phase, two at a time. First the sub and the far mid. One of the benefits of this is that it sets up good stage width. Next cut the sub and do the two mids, tweaking only your near mid. I don't really hear my tweets to TA them. I just set the far tweet to the same distance as the near mid so that the two fire together and seperate the tweets by the same distance as the tweets. This works great. The tweets play 3khz and above, this range is not affected by phase difference but more by left / right intensity, which is an eq function. However, if I don't set the tweets like I described they never sound right.

Listening to a good 2ch setup is great for learning and to have a ref point. Try visiting some high end audio stores. Some of the good ones will let you sit and listen for a few hours. Carry different material that you normally hear.

Ishouldbeworkin

MacLeod wrote: »

After youve done this, then you level match. After youve level matched you go back thru and fine tune with the tracks I just listed.

After youre done, save this tune to a preset. Go in the house. Now the next day live with this tune while you drive around and pick out the things you dont like. That night try to fix those things. Once you go thru and fix what you think you didnt like, save that to a preset. Now compare them both. A/B them and see what you think.

This is an endless process by the way.

Well, I spent some time yesterday and today EQing. I am not quite going in the order suggested because i don't yet have the remote to adjust the EQ without going into my trunk. So, I started with level matching. ( Luckily the process is an endless loop so starting in the middle shouldn't hurt too much, hehe )

Yesterday was my first attempt going through all channels independently and using my digital SPL meter to check output levels with 1/3 octave pink noise. After adjusting EQ levels I listened to it in the car today. It sounded sooo bad, totally off balance.

I though that perhaps when I had taken my first sets of measurements there could have been too much ambient sound distorting my readings. So, I went to the park to take another set today and adjusted again. It is starting to sound a little better now.

My HU (Eclipse CD7200 mkII)about got thrown through my window though when it decided to loosen and send nothing but bass blaring through my sub when it had been completely turned down, then taunting me by refusing to snap back into place. The face keeps popping off also, sometimes it is just sitting half way off when i get into the car.(Wish I still had the box and receipt from a year ago.)

I mainly mentioned that because I might upgrade my HU(though i am not sure to which one yet). Feature wise, I like my HU, it has 6 pre-outs, 3 way crossover, time alignment controls. The Alpine CDA-9886 seems to have similar features but I am not sure of what other HU's are in this class currently.

MacLeod

Level matching can make a HUGE difference so if thats all you can do right now thats fine.

Try this approach. Take the filtered pink noise and your SPL meter and after you level match, go thru each one with all drivers playing and look for any dips and peaks. You want to get them all within 2 db of each other ideally. There will be some you cant fix due to phase issues and such but try to get them close.

Once youve got things relatively flat then you can change things to suit your music better.

Remember, the main purpose for an EQ is to correct for things that crap up your speakers sound like windshields, seat cushions and so on.

Mac, do you have pics of your install? IIRC, I remember you saying you wanted to fire them into the windshield. I'm just curious on what you decided worked best as far as location.

I left them in the corners firing up into the windshield. They are angled slightly back tho. Im not using the SR tweeters anymore. Since theyve been discontinued I cant get any spares and I cant go to big competitions without spare drivers. Im currently using Morel home audio tweeters (MDT12).

arun1963

DSkip wrote: »

.....

(which btw is going to be a boy! )

Another polkie on the way. Congrats. Get ready to have your world as you know it, turned on its head. Mac can help you on that as well.

DSkip wrote: »

My one concern is I'm not getting the "envelope" experience like I was.... are there ever moments where it sounds like somethings happening behind you, or in a far corner?

Yes and yes. But its going to happen a bit down the road. The more you stick at it, the better the sound will get over a period of time. Its a slowish process. To get the 'experience', you will have to take out 30-40% out of the sound that you have right now. The impact will come from removing the impurities in the sound.

Once you've set the TA and done the balancing for L/R, you will have to take this 30-40% out during level matching with your spl meter and while dialing in tonality across the sound ranges. With that in mind over the medium term think about cutting before you think of boosting.

Some basic stuff to remember, when adjust for L/R balance where the left side hotter by 5db, cut the near side by 3db and boost the far side by 2. When youre level matching, cut or boost both L & R side together, so that you maintain the l/r balance.

Break the sound into ranges, mid bass 80-200hz, midrange 300-1kz, upper mids 2-5khz and then your highs 5khz and higher. Attenuate eveything except the range you're level matching (say midrange) and then try to diial in tonality within this range. Its easier to level match over 2-3 octaves at a time rather than all 10. This will also give you an idea on what the part of the sound this range is. Note the settings that sound best tonally in this range and try doing the same over another range, say your mid bass.

Now play both the ranges and see how they shape up together. You may find that something that you boosted while doing a range now needs to be attenuated and vice versa...:). Now do another range and try and merge that.

DSkip wrote: »

arun - you were saying something about actual/TA distances. How do you come up with the TA number?

By ear. I don't have a formula for it . I just gave the numbers to show how the physical distance and TA distances are not really connected. So you have to do it by ear. How do you time align? In inches or ms?

The frequencies that are most affected by phase shift are your mid bass and mid range. 80-200hz is about 70% phase and 30% balancing for L/R. 300-800hz is about 50/50 and above 1khz its largely about L/R intensity. So when youre setting TA you may want to cut everything except the 80-500 range and then set the TA.

arun1963

What I love about cp is that a thread like this is not jumped on by a horde of proof seekers who want evidence that can be measured and calculated. That's partly due to the fact that we don't get as many hits as some of the other forums.

The other part I guess is Mac. It's tough to argue with subjectivity that has the stamp of ultimate objectivity.

I hope this one goes on for a bit.

Ishouldbeworkin

MacLeod wrote: »

Try this approach. Take the filtered pink noise and your SPL meter and after you level match, go thru each one with all drivers playing and look for any dips and peaks. You want to get them all within 2 db of each other ideally. There will be some you cant fix due to phase issues and such but try to get them close.
Once youve got things relatively flat then you can change things to suit your music better.

I used all speakers to take some readings through the whole frequency range today and already see some obvious problems (such as having virtually nothing 16kHz and above). Some things should be intuitive and relatively simple to fix, such as the peak around 1kHz or the general level of the sub bass freqs. However, some I am not sure what to do with my peak at 5kHz. I am not sure about this one mainly because this is the point at which I currently have my mids/highs crossed, so I don't know if I should attenuate it on the mids(rear channel on my eq) or my tweets( front channel on my EQ) or both. Is there a general rule for this, or is it one of those things that depends on the vehicle?

I created a spreadsheet graph and uploaded my readings today so you could see where I am currently.

Ishouldbeworkin

arun1963 wrote: »

Another polkie on the way. Congrats. Get ready to have your world as you know it, turned on its head. Mac can help you on that as well.

Some basic stuff to remember, when adjust for L/R balance where the left side hotter by 5db, cut the near side by 3db and boost the far side by 2. When youre level matching, cut or boost both L & R side together, so that you maintain the l/r balance.

Yeah, congrats! My brother has a boy on the way too. Being an uncle is great;)

I started to adjust levels with this combination of both attenuation and boost after my first try was a train wreck. It seems my EQ boosts/cuts more than the digital readout would have me believe. It is going to take a while. Today the weather stinks, so I will probably have to wait until tomorrow to do more adjustments. (40's and raining out...so much for sunny north Florida! )

MacLeod

Ishouldbeworkin wrote: »

I used all speakers to take some readings through the whole frequency range today and already see some obvious problems (such as having virtually nothing 16kHz and above). Some things should be intuitive and relatively simple to fix, such as the peak around 1kHz or the general level of the sub bass freqs. However, some I am not sure what to do with my peak at 5kHz. I am not sure about this one mainly because this is the point at which I currently have my mids/highs crossed, so I don't know if I should attenuate it on the mids(rear channel on my eq) or my tweets( front channel on my EQ) or both. Is there a general rule for this, or is it one of those things that depends on the vehicle?

I created a spreadsheet graph and uploaded my readings today so you could see where I am currently.

Looking at your readings, theyre pretty normal. Dont worry about the 16 and 20 KHz numbers. They drop off in every car Ive ever seen. If you had one of those $1500 Audiocontrol RTA's to play with you would see they dont drop off as much as you think. The problem here is your $50 microphone versus a $1500 microphone.

Save your current settings for now as a baseline.

Bump up 125 a notch or two. This frequency gives a fatter sound to the midbass. Makes the male voice sound more unnatural but makes kick drums and rock sound better.

250-400 needs to come down, especially 315. These frequencies give a more "cardboard" sound to vocals. Kinda like youre listening to them thru a wall.

800-1000 is more of an echoy or reverby type sound. Both of those need to come down and be more in line.

Bring 1.6 down. This is the start of the sibilance.

5 - 6.3 do look too hot so you should experiment with these however Ive found that SPL readings on the 5-8 K range are deceiving. Try cutting them one at a time but dont be surprised if it doesnt sound right to you. If thats the case, leave them. But Id bet youll need to cut them some especially if you listen to any music with heavy guitars. These frequencies can become fatiguing.

Remember, its YOUR ears that matter. If you do the adjustments I told you and you think they sound like crap, then they do. The ears are the final judge and you cant tune a car without hearing it so just take this as ballpark starting points.

Ishouldbeworkin

I went and made some of the adjustments and spent some time just listening to a few CD's. I will probably wait a bit more before doing another measurement and see how much I can adjust by feel.


Had another HUGE spike of bad sound....like taking two wires and rubbing them together in a speaker circuit...it was very loud and scared the heck out of me, both out of surprise and out of worry for my poor SR's. I don't know if the problem is my loose faceplate, or a bad ground somewhere. Shortly after the spike, I turned the engine on to save my battery and when I did...the sound cut completely off...It was strange..the head unit spectrum display still showed music playing from the CD, but no sound. Turned the car off, no sound still. A few minutes later after fidgeting with the faceplate and turning the car on/off I finally got music playing again. Sigh.

MacLeod

That sounds like either a ground or a power wire is shorting out. Possible the power wire as a loose ground normally doesnt cause a loud crack thru the speakers.

Id check all your wiring and make sure its all terminated properly and make sure you didnt accidentally screw something down and into the insulation of a wire somewhere or something else like that.

arun1963

Ishouldbeworkin wrote: »

I created a spreadsheet graph and uploaded my readings today so you could see where I am currently.

There is practically no information in the 16-20khz range. But it does impact the 1-12khz range. Like Mac said 5-6 looks peaky and 2-4khz is a pronounced dip.

MacLeod wrote: »

Ill go up to 1 octave above the crossover point on the mids and 1 octave below on the tweeters with the EQ'ing.

That right there, may be your solution. You're crossing at 5khz, go back to scratch and reset 2.5khz to 10khz for all four drivers. First measure each driver in this range, then balance for left / right, do the mids first then the tweets. When balancing a frequency for L/R, try to balance either around the lower number or between the two readings.

Now go back and take a reading in this range with both mids playing. Plot this. Now do the same for your tweets. You should see a pattern in the plots. The one fr the mid should rolling off from about 2-3khz and the one for the tweet should be rolling off around 6khz and lower. These are just rough numbers for you to explain the point.

From 2.5-4khz you want the mids to be louder than your tweets and from 6khz upwards your tweets should be taking over from your mids. It wont be a perfect slope either ways, thats fine. The trend should be visible. Now play all four drivers and take a reading across this range. You may find that you now have a slight dip at 5khz, that may need correction.

More importantly how does it sound now? I'm afraid that we're getting trapped with numbers. You have to go out hear a good 2ch, then hear your setup and describe where you think you're lacking. How about a post describing what you like and dislike about the sound that you have currently?

Ishouldbeworkin

arun1963 wrote: »

More importantly how does it sound now? I'm afraid that we're getting trapped with numbers. You have to go out hear a good 2ch, then hear your setup and describe where you think you're lacking. How about a post describing what you like and dislike about the sound that you have currently?

I agree that this could be a problem. Of course, since I am working on a graduate degree in economics, I know how much numbers can fool you:)
You might have missed it, but I mentioned that I will probably wait a bit more before doing another measurement and see how much I can adjust by feel.

I don't have access to a good 2 channel setup at the moment, but use my simple Bose computer speakers as a kind of reference point.(still reading, lol?) I got the chance to just listen a bit from several different albums and have a few impressions that I can share:

- I found the music to be a bit suffocating, or forced onto me, rather than me just observing the sound in a room where it happens to be playing. I am not sure about how else exactly I should describe it.

- The mid ranges seemed overpowering as well, especially electric guitars, although acoustic guitars sounded better than I can recall in the past.

- Some vocals felt strained, as if it was like the speaker was just about to distort.

I have been exploring records to die for (r2d4) to get more informed about albums, from artists I already like, that were recorded well. To be honest, I had previously not paid any attention to who recorded an album or if it was a remastered version.
Also there are some artists that I would have never known about prior to this process that I found I enjoy listening to, such as Rebecca Pidgeon (Spanish Harlem, of course, but I ended up liking several songs on "The Raven").
With that said, hopefully my collection of music that is good to use for reference will be increasing and I will be able to give improved assessments.

jay27

I left them in the corners firing up into the windshield. They are angled slightly back tho. Im not using the SR tweeters anymore. Since theyve been discontinued I cant get any spares and I cant go to big competitions without spare drivers. Im currently using Morel home audio tweeters (MDT12).

Does this mean you will soon switch midbass drivers too since Polk isn't making the SR line anymore?

MacLeod

Yup. Sucks but thats life I suppose. Doubt itll be for a while. Ive got a couple spare SR 6.5" mids so I should be ok. Ill use them as long as they play. I still think theyre among the best mids on the market.

arun1963

DSkip wrote: »

What other ones compare to the SR? I'm curious because I went on some other car-audio dedicated forum and polk got constant bashing. I read a few posts that even commented on a lack of detail in the SR, which blew me away. I would like to know what they are comparing it to that makes the SR sound so bad.

Folks who have spent 2x $$'s in buying the scans, dyns, morels et al, would have problems accepting that a $500 speaker can keep up with their stuff. Don't worry, Polk gets rough handled on a lot of forums. These are people who believe that more money is better sound.

Linked to the above is the fact that 99% of the people on these forums have no clue about tuning. So they dont understand how tuning can get the best out of any speaker.

That said, there are some excellent speakers out there. Top end Morel elate and supremo, Hetz Mille (ML2), are a couple that I have heard. The scans which I havent heard are also there. But these are in the 1.5-2x range when compared to the SR's. Are they better than the SR's? Yes in some respects. Is that gain, worth the extra $$ for me? Since I'm not competing, no.

arun1963

Ishouldbeworkin wrote: »

I agree that this could be a problem. Of course, since I am working on a graduate degree in economics, I know how much numbers can fool you:)

So was it an economist who said something like 'Numbers are like a bikini. They reveal a lot, while hiding the critical stuff'. Poor joke but apt in a twisted way.

Ishouldbeworkin wrote: »

might have missed it, but I mentioned that I will probably wait a bit more before doing another measurement and see how much I can adjust by feel.

You're right I missed it. If I had picked it, I would have said this earlier. I also wouldn't have worried about spending too much time on numbers.

If your basic settings of TA or the way you have corrected for L/R balance are out, all the level matching you try will only take you around in circles. Trust me, I've been there and done that. I spent 2 months trying to level match with my base settings out and I got nowhere.

Set the eq to 0 for all frequencies then measure one driver at a time. Do your mids from like 20-10khz and your tweets from 800-20khz. Put the raw data on a format like the one attached (can't upload an excel file). Lets look at it and see if we can get better balance. Before you do this, make sure your meter works properly. Go back and forth between any two frequencies and test each 3-4 times. Does the meter give consistent results or does it vary from reading to reading?

Ishouldbeworkin wrote: »

don't have access to a good 2 channel setup at the moment, but use my simple Bose computer speakers as a kind of reference point.(still reading, lol?) I got the chance to just listen a bit from several different albums and have a few impressions that I can share:

- I found the music to be a bit suffocating, or forced onto me, rather than me just observing the sound in a room where it happens to be playing. I am not sure about how else exactly I should describe it.

- The mid ranges seemed overpowering as well, especially electric guitars, although acoustic guitars sounded better than I can recall in the past.

- Some vocals felt strained, as if it was like the speaker was just about to distort.

You're right about Bose being a poor ref point. All three issues you mentioned, are linked to your peak at 5-6.3 range, to varying degrees.

MacLeod

DSkip wrote: »

What other ones compare to the SR? I'm curious because I went on some other car-audio dedicated forum and polk got constant bashing. I read a few posts that even commented on a lack of detail in the SR, which blew me away. I would like to know what they are comparing it to that makes the SR sound so bad.

Theyre not comparing them to anything other than what they "think" Polk is. Polk is a maintstream speaker company and has mainstream outlets like Circuit City and Crutchfield as distributors. In small minds, this automatically means its crap. Only some special hand made speaker from some far off country can sound good.

I think Ive proven that to be a load of bull over the passed 5 years. With the Polk SR's, Ive competed and beaten pretty much every brand of speaker out there.

arun1963

MacLeod wrote: »

I think Ive proven that to be a load of bull over the passed 5 years. With the Polk SR's, Ive competed and beaten pretty much every brand of speaker out there.

This is exactly why I bought the SR's over the Mille's.