SQ Steps

arun1963

Hi,

Looking for advise on sq enhancement from my set up.
hu: pioneer 880prs all settings at 0 eq settings largely at 0 some at +1 some at -1. Time alingment used.
Front : Polk 6.5 momo's tweets at -6 crossed over from hu at 63hz 12db/oct
Rear : momo 691 set at -3 gain from the hu crossover at 80hz 12db/oct
Sub: momo 2124
4 ch amp: pa500.4 front gain 11 o'clock rear at 9:30
Mono : 400.1 I know sub is under powered.

Have had this setup for abt a year now. Front doors deadened with dynamat. Basic 1 layer on outer skin of door, 2x12" behind each mid and sealed with one layer. My question is what should I do next to build sq?

1. How important are the cables that run up and down the length of the cabin and connect the amp to the crossovers? crossovers to speakers? hu to amp?

2.Is it better to take up one area at a time and focus on that or do a bit of everything and then come back to the doors? Value in deadening the floor wells and behind the dash?

I basically want to "hear" as close to the max potential of the speakers while setting up the base for an eventual upgrade to sr fronts and sub (momos will go to the back)

tks a ton

arun1963

....two other issues:

1. When I started using TA I measured the distance to each speaker from my driving position. I fed those actual figures in and listened. At these settings it always felt like the sound was comming from directly in front of me ie the right front tweeter was dominating (I am in India and we have right hand drive here). I then increased the distance on front left by 2" and reduced the distance on front right by 2" and reduced the eq setting for FR to -1 for 3.5 & 8khz. Bingo, the sound was now to my left ie the centre of the windscreen. Now how do I pus the sound outwards ie so that it comes from over the hood?

2. When parked I sometimes listen with the windows rolled down wow the sound is much more open....why? hy cant I get the same sound with the windows up?

tks

MacLeod

arun1963 wrote: »

1. How important are the cables that run up and down the length of the cabin and connect the amp to the crossovers? crossovers to speakers? hu to amp?

Not very important. As long as theyre not inducing any noise youre fine.

2.Is it better to take up one area at a time and focus on that or do a bit of everything and then come back to the doors? Value in deadening the floor wells and behind the dash?

Start with the doors first. Put as much on there as you can afford.

I basically want to "hear" as close to the max potential of the speakers while setting up the base for an eventual upgrade to sr fronts and sub (momos will go to the back)

If youre wanting the best SQ possible - ditch the rear speakers. All they do is interfere with your front speakers. Different speakers playing the same frequencies but hitting your ears at different times causes phase issues, cancellation and smearing detail not to mention pulling your soundstage to the rear instead of high and deep up on top of the dash where it should be.

1. When I started using TA I measured the distance to each speaker from my driving position. I fed those actual figures in and listened. At these settings it always felt like the sound was comming from directly in front of me ie the right front tweeter was dominating (I am in India and we have right hand drive here). I then increased the distance on front left by 2" and reduced the distance on front right by 2" and reduced the eq setting for FR to -1 for 3.5 & 8khz. Bingo, the sound was now to my left ie the centre of the windscreen. Now how do I pus the sound outwards ie so that it comes from over the hood?

Width and depth are dependent on speaker placement. Youll have to mount your speakers farther forward to achieve this.

2. When parked I sometimes listen with the windows rolled down wow the sound is much more open....why? hy cant I get the same sound with the windows up?

Reflection. With the windows up youve got waves bouncing around and interfering with one another. With the windows down those waves just cruise on out of the car. You can still get around this with not only Dynamating but also using foam stashed in strategic places.

cadenceclipse

12 gauge and nice rcas don't hurt, "behind the dash"? maybe for engine noise?, kick panels do it

MacLeod

Ideally you would pull out the entire interior and Dyanamt everything but thats pretty pricey and very time consuming. The doors are the most important part assuming thats where your speakers are but putting it anywhere helps.

arun1963

Thanks for the feedback Mac & Cadence. Here's what I'm going to do next sunday. I'm going to leave the cables alone for now and focus on the front doors. Would appreciate your opininon on the rambling below:

1. I will disconnect the rears and bi amp the momo's up front. Will connect the tweets to the front chanel with gain at 9 o'clock and the mids to the rear chanel gain at 11 o'clock (to start). Various threads have mentioned that bi amping gives greater flexibility while tunning. I assume this means you can play with the gains on tweets and mids to find the best balance.

2. I will work on the doors. Question: Once I have the door panel removed, I will need to need to take off the layer of dynamat that seals the door. Is this reusable ie will it stick properly again? If not can I use some super glue? Once the sealing layer is off, I will cover "EVERY" bit of exposed metal on the inside of the door with strips / cut outs of dynamat. We dont get foam here. Should I glue on some pollyfill (stuff used in pillows)? If so what are the critical areas where this needs to be done? I kknow each door is diff, but just some pointers would help. The mid bass is currently mounted on the door frame with the plastic ring supplied by polk. Should I ditch this and go with a mdf baffle? Currently I do hear vibrations occasonaly from the door panel. Any other suggestions?

Last night (I spend a couple of hours every night listening and tuning and floating in the music when I hit the sweet spot ) I turned off the sub, faded to the fronts just to hear what the fronts alone sound like (eq set to 0 for all frequencies). I think listening to only the fronts would give a good idea on how well dampended the doors are. The sound left a lot to be desired. Tinny, slightly harsh mids and lows. Hearing the fronts only, I dont expect bass punch, but I feel the 60-315hz range should atleast be solid and tight. It wasnt.

3. The third issue concerns the sub. The 12" momo sub 2124 is currently enclosed in a ported encl 1.3 cuft. It is powered by the pa 400.1 mono amp. The polk dealer sold me this amp. Its basically my fault that I didnt do my homework. Anyway stuck with it for now. I know a sealed encl would give tighter bass. I am getting a sealed enclosure made 12"x12"x11" depth = 0.91cuft. Will 11" depth be sufficient? Getting the encl made in real wood and will line the inside with dynamat and wads of cotton wool. Currently if I cut out the front and rears and only hear the sub, there is a lot of resonance / disturbance at 50hz. I can run 20hz and 31.5hz at 0 on the eq without distortion. (sub cuts off at 63hz with a 18db/oct slope). Will I have the same prob with the sealed encl? I feel 50hz is critical as this gives the midbass solidity.

I use the TA to place the low freq from the sub on the mid bass. To give an example, hearing front mid bass only = full moon; getting the sub to cover the front mid bass = lunar eclipse. I have set up the sub distance so that I hear a 2/3-1/2 moon. This way the bass is up front but the mid bass has its own identity. Sorry about the half **s explanation. Based on this getting 50hz right is critical for me.

something tells me above is going to be a 2-3 sunday project

your inputs as always are greatly appreciated.

tks n rgds
arun

MacLeod

arun1963 wrote: »

1. I will disconnect the rears and bi amp the momo's up front. Will connect the tweets to the front chanel with gain at 9 o'clock and the mids to the rear chanel gain at 11 o'clock (to start). Various threads have mentioned that bi amping gives greater flexibility while tunning. I assume this means you can play with the gains on tweets and mids to find the best balance.

I would suggest setting the gain the same for both tweets and mids and control the output level with your HU. Bi-amping is absolutely the best way to go. It allows you to tune each driver independently.

2. I will work on the doors. Question: Once I have the door panel removed, I will need to need to take off the layer of dynamat that seals the door. Is this reusable ie will it stick properly again? If not can I use some super glue? Once the sealing layer is off, I will cover "EVERY" bit of exposed metal on the inside of the door with strips / cut outs of dynamat. We dont get foam here. Should I glue on some pollyfill (stuff used in pillows)? If so what are the critical areas where this needs to be done? I kknow each door is diff, but just some pointers would help. The mid bass is currently mounted on the door frame with the plastic ring supplied by polk. Should I ditch this and go with a mdf baffle? Currently I do hear vibrations occasonaly from the door panel. Any other suggestions?

An MDF baffle would be best. I use the plastic spacers that come with the Polks but I wrap them in Dynamat. I hate installing and can never get the MDF cut right to fit and the plastic ones fit perfectly so I use them. Once you peel the Dynamat off, you wont be able to reuse it. You can but it wont stick as well which defeats the purpose. Its meant to bond with whatever its applied to to add mass. Dont use foam or anything like it in the doors. It will soak up moisture and give you problems like rust or mildew.

Last night (I spend a couple of hours every night listening and tuning and floating in the music when I hit the sweet spot ) I turned off the sub, faded to the fronts just to hear what the fronts alone sound like (eq set to 0 for all frequencies). I think listening to only the fronts would give a good idea on how well dampended the doors are. The sound left a lot to be desired. Tinny, slightly harsh mids and lows. Hearing the fronts only, I dont expect bass punch, but I feel the 60-315hz range should atleast be solid and tight. It wasnt.

You can fix that with tuning once you get them hooked up. More than likely, the mid on your side is hot in the 250-400 Hz range and weak on the other side.

3. The third issue concerns the sub. The 12" momo sub 2124 is currently enclosed in a ported encl 1.3 cuft. It is powered by the pa 400.1 mono amp. The polk dealer sold me this amp. Its basically my fault that I didnt do my homework. Anyway stuck with it for now. I know a sealed encl would give tighter bass. I am getting a sealed enclosure made 12"x12"x11" depth = 0.91cuft. Will 11" depth be sufficient? Getting the encl made in real wood and will line the inside with dynamat and wads of cotton wool. Currently if I cut out the front and rears and only hear the sub, there is a lot of resonance / disturbance at 50hz. I can run 20hz and 31.5hz at 0 on the eq without distortion. (sub cuts off at 63hz with a 18db/oct slope). Will I have the same prob with the sealed encl? I feel 50hz is critical as this gives the midbass solidity.

The punch in the midbass is 50-63 Hz. Dont put Dynamat on the inside of the box. If you want to you can put it on the outside but honestly you dont need to use it at all if you use thick enough wood and your box is built properly. The sub will sound better in a sealed enclosure. Youll want to steepen the slope on the sub. 18 db is a little shallow and youre getting a lot of 100+ Hz which is very boomy.

I use the TA to place the low freq from the sub on the mid bass. To give an example, hearing front mid bass only = full moon; getting the sub to cover the front mid bass = lunar eclipse. I have set up the sub distance so that I hear a 2/3-1/2 moon. This way the bass is up front but the mid bass has its own identity. Sorry about the half **s explanation. Based on this getting 50hz right is critical for me.

Add delay to the front speakers and leave the delay at 0 for the sub. You get your imaging cues from what you hear last so by adding delay to the front stage, youll hear them AFTER you hear the sub. So the sub will kick and youll hear the imaging cues for the bass drum or whatever a slip second later from the mid's and your brain will put the bass up front.

arun1963

would suggest setting the gain the same for both tweets and mids and control the output level with your HU. Bi-amping is absolutely the best way to go. It allows you to tune each driver independently.

Will get it done from a professional installer. I am all thumbs and a technical idot to boot. Only saving grace are the ears.

You can fix that with tuning once you get them hooked up. More than likely, the mid on your side is hot in the 250-400 Hz range and weak on the other side.

WOW and mmmm in the same breath. Increased 200/315/500hz on the passenger side and reduced 3.15/5khz on my side....mmmmm

The punch in the midbass is 50-63 Hz. Dont put Dynamat on the inside of the box. If you want to you can put it on the outside but honestly you dont need to use it at all if you use thick enough wood and your box is built properly. The sub will sound better in a sealed enclosure. Youll want to steepen the slope on the sub. 18 db is a little shallow and youre getting a lot of 100+ Hz which is very boomy.

Ok no dynamat in the enclosure. Stuck with the 18db slope. If I use crossover from the amp I only get 12db. My HU allows max of 18db. This is why I set my sub at 63hz on 18db. I figure this way I will get upto 75-80hz which is ok. Fronts also at 63hz on a 12db slope, again this is the max I can do. 9887 scores over the 880 on this for sure.

Add delay to the front speakers and leave the delay at 0 for the sub. You get your imaging cues from what you hear last so by adding delay to the front stage, youll hear them AFTER you hear the sub. So the sub will kick and youll hear the imaging cues for the bass drum or whatever a slip second later from the mid's and your brain will put the bass up front.

This is how I have it set up. The fronts have added delay and the sub is at exact measuured distance.

One last issue before I go the re-jig. Currently tweeters are in stock location at the base of the windows. They are facing and firing at each other. I would like to mount them in a location that gives best stage and allows me to ppush the sound beyond the windscreen, but I dont want them very far from the mid...........any suggestions?

Tks for all yr help and will let you know how it sounds once the re-jig is done.

cadenceclipse

"professional" installer..good luk, i'd give your thumbs a try. those guys r few n far between. saving grace is your best weapon..ears and time. just a suggestion, maybe you tried, but thinking maybe 80hz on fronts. as far as tweets, could u angle them towards u? i have mine down low in kick panels and love them there.

MacLeod

Stick the tweeters in the A pillars about halfway up and firing at the opposite head rest then cross them over pretty high. This will let the mids carry more of the imaging cues and since theyre mounted further wide they will give the stage more width.

JoshParsons84

Hey Mac I've got kick panels should I keep my tweets in my kick panels or put them in my A-pillars?

candaddy

This is a great thread, lot's of good advice!

Aiming speakers (especially tweeters) is really a simple thing.

When the speaker is facing directly at you, it will be it's loudest (barring canceling reflections, etc). Because of this, the "crossfiring" configuration has become really popular because it aims the near side speaker away from you and the far side speaker (which is further and therefore not as loud generally speaking) right at you, hence the volume of each tends to even out.

The most common problem you have is the near side speaker is most noticeable and so you'll tend to want to aim it away (aim them more forward, or towards each other). If you have a kick panel setup with the tweeters down there, then sometimes the far side will sound louder and the speakers will have to be aimed more rearward (away from each other and more towards the back of the car).

With the momo tweeters you should be able to just swivel them in the cups far enough for the install you're talking about, it's free and should be mildly noticeable.

Mcleod is right about ditching the rear fill, that was going to be my first suggestion right off.

My experience with the momo set is that bi-amping them makes a noticeable difference. I never liked them with the -6 setting, I always used the -3 because the top end seemed to disappear with them at -6. Once you bi-amp though, I'd suggest setting the attenuation on the crossover to 0 instead and then use the amp gain (or the head unit as Mcleod suggested) to lessen the tweeters however you feel fit. You need to strive for a good match in volume at the crossover frequency for best phase coherency however. If it blends well there, but not elsewhere, don't cut or boost one driver or the other to try to even it out, use your eq instead.

My experience with the Momo's was that the tweeters have a reasonable response curve, but the mids had some dips in the response, so you end up with a couple holes in the midrange which kills some "clarity." I seem to recall that I had to cut 500hz by a lot but boost around 800 and 1600. I can't remember now, but playing with the eq above 300 hz and below the crossover frequency should help. Each install will be different, so my settings probably wouldn't work for you anyway.

The last thing I do with the eq is adjust each frequency band for proper left and right response. You can do that with an RTA very easily, but it's also possible to do it by ear with band limited pink noise. The Autosound 2000 test disk number 103 has 1/3 octave band limited pink noise and by listening to each band, you can adjust your eq such that the sound will be centered wherever you'd like (in front of you or in the middle of your dash, however you desire). As you do that, you'll probably find that each side needs to be tweaked left or right differently at different frequencies (McLeod is familiar with this one) and once you get them all dialed in, the soundstage improves dramatically.

I should also mention that at one point, reversing the phase of the tweeters helped a lot. If they are totally out of phase with the mids, you'll be able to tell exactly where they are. If they are in proper phase with the mids, then they will tend to disappear, which is obviously what we'd like to have happen. In my install, in-phase/out of phase made the difference between a left and right speaker each fighting for my attention and a coherent center image with no indication of where the speakers were.

arun1963

hey guys thanks for all the great advise. Responding to Mac and Candaddy.....

Stick the tweeters in the A pillars about halfway up and firing at the opposite head rest then cross them over pretty high.......

Thats where they will go. halfway up the the A pillars to the centre of the mid in my car is 22". The momo catalogue talks about using the mid range extension on the xover if the tweeter and mid are at a significant distance. Two questions: 1. Where is this mid range extension switch? The xover only has switches for tweeter level and input mode (single/dual, dual I assume is for bi-amping). 2. Do I need to use this extension?

Aiming speakers (especially tweeters) is really a simple thing........ you should be able to just swivel them in the cups far enough for the install you're talking about, it's free and should be mildly noticeable

Makes sense. In the current stock position, the near side tweeter is over bright in the 3.15-8khz range. Attenuating these frquencies for the near side tweet helps but it hurts the solidity of the sound. So its a gain some lose some kind of thing.

Mcleod is right about ditching the rear fill, that was going to be my first suggestion right off.

I have a four hour commute, 6 days a week, plus I spend a couple of hours most nights (after playing with my daughter and putting her to bed) just listening to music. This is when the music sounds the best, no road / wind / engine noise. Neighbours think I'm senile, wife is convinced I'm going thru a mid life crisis........Quote: "you know no other woman would tolerate you, so youre fixated on this SQ thing".....:D she's prob right abt the other woman bit. But seriously how come the SQ domain is so male centric? Dont women get moved by sound?

Sorry abt the rambling. Last couple of nights I have been listening to the setup playing only the momo's up front and the sub. There is a lot more detailing in the sound, the stage is more focused.......but the surround effect is lost. Its better in some ways but very different. I keep telling myself that improving the damping, biamping and putting the tweets on the a pillar, will do the following:
1. Sound will be richer
2. Mid bass wil be fuller
3. Mids and highs will be louder and clearer as each drive will prob get more power bi-amped.
4. Soundstage will be higher, more focused and will have greater depth.

Pls let me know if the above is correct.

My experience with the momo set is that bi-amping them makes a noticeable difference. I never liked them with the -6 setting..............
. If it blends well there, but not elsewhere, don't cut or boost one driver or the other to try to even it out, use your eq instead.

Currently the tweeters are at -6. The xovers are mounted behind the door panel and as such are inaccessable. A major PI the A. Is it ok to mount the xovers in the boot and the run the wires to the speakers? In stock locations the tweets are over bright at 0 and just abt ok at -3. Frankly I've got quite used to them at -6. But will try from 0 again once bi-amped.

My experience with the Momo's was that the tweeters have a reasonable response curve, but the mids had some dips in the response, so you end up with a couple holes in the midrange which kills some "clarity." I seem to recall that I had to cut 500hz by a lot but boost around 800 and 1600. I can't remember now, but playing with the eq above 300 hz and below the crossover frequency should help. Each install will be different, so my settings probably wouldn't work for you anyway.

My $0.02 on tuning the eq settings (playing front and sub only):

1. 20hz set at 0 L&R

2. 31.5hz set at 0 L&R

3. 50hz set at -1 L&R

4. 80hz set at +1 (front hpf at 63hz 12db/oct, sub at 63hz 18db/oct)

5. 125hz set at 0 L&R

6. 200hz set at +1 for L and 0 for R. Driver and steering are on the right in India.

7. 315hz set at +1 L&R, slope 6db/oct for left and 12db/oct for right.

8. 500 set at -1 L&R. I think 500 and 315 are linked. To boost 500 you have to boost 315 too, else sound gets a serrated edge.

9. 800hz set at +1 L&R. Boosting 800 is sweeter than boosting 500 but it increases the overall brightness. Hence you have to attenuate something in the 3.15 to 8khz (depends on the CD).

10. 1.25khz set at 0. 800 and 1.25 are inversely related if you raise one you have to lower the other.

11. 2khz. Set at +1. This frequency binds the mids. On CD's that have very bright mids, I set this to 0. Set at +1, it also tells me if I have overboosted the other mid frquencies. The sound looses its sweetness and becomes harsh.

12. 3.15khz set at 0 for left and -1 for right. This is a PIA frequency. Its good for the higher end of male vocals and guitars etc but it can also cause tinny sound, harshness etc. The jury is out on this one.....how do you'll handle this frequency?

13. 5khz set at either 0 or -1. Boosting this makes vocal hollow / echo'y its like taking the vocals and stretching them. I think setting this frequency at -1 or -2 and the xover at -3 i/o -6 would help.

14. 8khz set to +1. This adds overall brightness to the highs.

15. 12.5khz set to -1. There isnt much here in any case but setting it to -1 makes the highs softer and smoother.

16. 20khz set to 0. This gives the brightness to the very top end. If I find the highs getting over bright I keep this at and reduce some other high freq. I attenuate this only as a last resort.

Would love to hear about your views on the above.

The last thing I do with the eq is adjust each frequency band for proper left and right response. You can do that with an RTA very easily, but it's also possible to do it by ear with band limited pink noise.....you'll probably find that each side needs to be tweaked left or right differently at different frequencies (McLeod is familiar with this one) and once you get them all dialed in, the soundstage improves dramatically.

When tuning, i set everything to 0 and first set the TA, next I set the xover and slopes and the eq comes last. Whenever I have tried setting the L/R on each frequency it always ends up blowing holes into the sound balance. Is there a link to download the pink noise cd? Will try that.

One last question, the momo tweeter is crossed over at 2600hz factory setting. Can this be increased to say 3.5? I feel this would clean up the highs. If yes, how and would it affect the waranty? The momo's have a 3 year warranty and I'm half way thru.

ciao and look forward to your response.

cadenceclipse

cross tweeter at higher freq by disconnecting crossover, biamping, and using crossover on hu or amp

MacLeod

One last question, the momo tweeter is crossed over at 2600hz factory setting. Can this be increased to say 3.5? I feel this would clean up the highs. If yes, how and would it affect the waranty? The momo's have a 3 year warranty and I'm half way thru.

Yes, this can be increased. This wont hurt the warranty as it would actually be easier on the tweeter.

JoshParsons84 wrote: »

Hey Mac I've got kick panels should I keep my tweets in my kick panels or put them in my A-pillars?

/QUOTE]

Its a personal preference. By keeping the tweeters in the kicks, you may get a little bit better tonality by having the mids and tweets so close to each other and not being interfered with. However, the bulk of your stage will be coming from the floor or rainbowing at best.

I prefer the tweeters in the A pillars as the tonal drawbacks can be overcome by tuning.

arun1963

cross tweeter at higher freq by disconnecting crossover, biamping, and using crossover on hu or amp

Pls tell me if my understanding is correct as under:

1. Disconnect the crossover and remove from the set up.
2. Run speaker wires from front left chanel on amp to front left tweeter, FR on amp to FR tweeter. Rear left from amp to Left midbass and RR from amp to right midbass.
3. On the amp set the front crossover to HPF, but the dial adjustment for the xover point runs from 50hz to 250hz only, how would I set it at 3.5khz?
4. Set the rear HPF at 63-80hz for the mids........

For bi-amping I will need 4 sets of cables running from the amp to the comps. Currently I have the two sets that came with the speakers. My istaller is urging me to ditch these and go for better cables. His logic - the resistance in the two polk cables and the two additional that I have to buy will be different. Any merit in this?
3.

cadenceclipse

3. use hpf on prs

what cables? speaker wire or rca?

candaddy

You can mount the crossovers in the trunk if you like, that won't hurt anything. The speaker wires that polk uses are totally adequate, I highly doubt you could ever hear a difference between a larger sized wire and that which comes with them. I guess I'm suggesting that you won't have to buy more wire than you need.

I ran mine actively crossed at 3200hz for awhile and the tweeters really didn't sound much different. Once you bi-amp the crossovers, then you will find that there is a better quality to the sound. I think you might be hearing the inter-modulation distortion from the crossover with the single amp source. I ran mine both with the single input and bi-amped using a variety of different amps, and they always sounded best bi-amped with the stock crossovers. I've heard very knowledgeable people state that bi-amping is a waste of amplifiers, but in doing my own open-minded testing, it just always sounded best bi-amped, so I stuck with what worked.

The manual talks about a frequency extension switch that doesn't exist, so you can ignore that option.

If your head unit doesn't have enough outputs and crossover functions to give you a high, mid and low output, then you'll have to retain the standard crossovers that came with the speakers or you'll have to buy an active crossover or head unit, etc.

Mounting the tweeters up high will bring the stage up and may make it seem wider and more spacious. I suspect that with the fronts dialed in, you will like the sound better than with the rear speakers playing at the same time. I would suggest you get a lot of speaker wire and play with different mounting positions. Assuming you cannot time-align the tweeters to the mids electronically, you'll have to measure their distance from you and do the best you can. What the means is that the right side tweeter should measure the same distance to you as the right side mid. If you can achieve that end, then you will have good phase coherency at the crossover frequency and around it. The same is true of the left side where you'd like the left side tweeter and mid to measure the same physical distance from your head. I use a tape measure to do this and it will make an audible difference. Once I got this right in my install I was able to correct the polarity at the crossover back to how it is supposed to be and that was much better than when I had it reversed with my tweeters at the wrong distance relative to my mids.

I got that test CD from Crutchfield, it's the Autosound 2000 test CD number 103 "My Disk." The other one I use a lot is the 102 which has a lot of good sound stage information on it. I think you'd like them both.

I suggested 0 on your tweeter attenuation with the bi-amping because once you bi-amp you can set the gain up or down on the tweeter channels to get them where they blend best with the mids. Setting them to -3 or -6 would mean you're wasting electricity heating up a resistor in the crossover for no reason. That won't really hurt anything, but it's also unlikely to help.

OH, and if you do bi-amp with the supplied crossovers as we've been talking, set the tweeter channels on your amp to HPF at the highest setting (250hz), this will lessen the amount the amp has to try to amplify for no reason and will also lessen the amount the crossover will have to absorb (so to speak), it's just more efficient and may increase the sound quality slightly.

cadenceclipse

candaddy, second paragraph u mention crossovers. u mean the supllied crossovers that came with the speakers? your saying to keep them or to go all active if possible, and ditch the crossovers, say, if using active hu? thinking bout bi-amping w/ cd7200, wondering if i should keep or ditch the supplied crossovers. sounds like u kept em..

arun1963

You can mount the crossovers in the trunk if you like, that won't hurt anything. The speaker wires that polk uses....... I'm suggesting that you won't have to buy more wire than you need.

Was examining the connections / wiring tonight. The guy who did the install seems to have done a real hack job. For the rears, there is a splice&join between amp and crossover on both L&R channels. There is a 10" wire that comes from the amp terminals and this is spliced and joined to the polk speaker wire connected to the xover. Moreover the the two 10" sections (L/R) channels, are different type of wires!! The spk wires running to the fronts do not have joints, but these are not the polk supplied wires. These are multi strand copper coloured wires encased in transparent plastic covering. I doubt they are pure copper, prob just copper plated. However the twisted core is thicker than the polk wire. So what did he do with the spk cables that came with the momo's?? Now when I bi-amp is it ok to connect the tweeters with one type of wire and the mids with another.......based on your suggestion above the ans would be yes?

The manual talks about a frequency extension switch that doesn't exist, so you can ignore that option.

Tks. I wreaked my head over that one for long time.

If your head unit doesn't have enough outputs and crossover functions to give you a high, mid and low output, then you'll have to retain the standard crossovers that came with the speakers or you'll have to buy an active crossover or head unit, etc.

HU is a pioneer 880prs. Yes it has seperate xover settings for bass / mid / high and Time Alignment.

Mounting the tweeters up high will bring the stage up and may make it seem wider and more spacious. I suspect that with the fronts dialed in, you will like the sound better than with the rear speakers playing at the same time....... What the means is that the right side tweeter should measure the same distance to you as the right side mid. If you can achieve that end, then you will have good phase coherency at the crossover frequency and around it. The same is true of the left side where you'd like the left side tweeter and mid to measure the same physical distance from your head. I use a tape measure to do this and it will make an audible difference. Once I got this right in my install I was able to correct the polarity at the crossover back to how it is supposed to be and that was much better than when I had it reversed with my tweeters at the wrong distance relative to my mids.

I love this thread. There is so much collective knowledge here. In my stock locations there is only an 9" seperation between the tweeter and mid on each side. The stock location for the mids is high up on the door panel. I thus set my time alignment from the tweeters. Like you, I use a tape and measure the distance the front L&R tweeter from the tip of my nose. Measured distance is 28" to the tweeter on my side and 45" to the one on the passenger side. The sub is in the boot facing and near the trunk lid at a distance of 76.5".

When I listen to it at this setting, the stage is dead centre in front but the sound is almost claustrophobic very tight. In order to open the sound up, I add TA to the fronts. One trick that seems to work while adding TA: front left measured = 45" front right measured =28". 45/28=1.60. Now when I increase the TA front right from 28' to 30", I increase the front left by 2"x1.6=3.2" so either 3 or 3.5" ie 48" or 48.5". This keeps the stage centred, opens out the sound and brings the bass from the sub upfront. I discovered this thru trial and error. Mac gives the scientific explanation for this earlier in the thread.

I suggested 0 on your tweeter attenuation with the bi-amping because once you bi-amp you can set the gain up or down on the tweeter channels to get them where they blend best with the mids. Setting them to -3 or -6 would mean you're wasting electricity heating up a resistor in the crossover for no reason. That won't really hurt anything, but it's also unlikely to help.

OH, and if you do bi-amp with the supplied crossovers as we've been talking, set the tweeter channels on your amp to HPF at the highest setting (250hz), this will lessen the amount the amp has to try to amplify for no reason and will also lessen the amount the crossover will have to absorb (so to speak), it's just more efficient and may increase the sound quality slightly.

gr8 and practical advise. Will do. For the last two days I have been only listening to the fronts and sub. I figured may as well get my ears and mind used to listening this way. At first it was so so and I kept going back to adding soundfill from the rears. Tonight I decided to re tune from scratch. For tuning my reference cd is Roger Waters - Amused to Death. Apart from the brilliant content and excellent recording, it has some amazing passages.

I set the eq flat and did the TA as mentioned above. Once the sound stage was centred, I came back to the eq and tweaked one or two frequencies each for low / mid / high. (-1 on 50hz, +1 on 315, +1 on 800, +1 on 3.5kz +1 on 8khz and -1 on 12.5kz). The sound improved but the stage was diffused. The sound balance had shifted to the right. Back to TA and reduced the TA for front right. The sound came back to the centre. The vocals, chorus and most instruments were centred, however the very high frequencies (12.5 & 20khz were still located on the tweeters. To overcome this I set 12.5khz to -2 for right and -1 for left and 20hz at 0 for right and -1 for left. Kept alternating between TA and setting L / R frequencies, till something strange happened. The sound suddenly bacome quieter. I mean the sound level fell by a few decibels, the music was quiter but a little muffled. I reduced the TA on the sub ie changed the distance from 76.5" to 75.5".

BANG! It was like going to a new level of sound. Crystal clear sound, focused stage. I have never reached this level while running the rears. Never heard this quality of sound. If bi-amping and changing the placement of the tweeters can improve this further, I am at a loss for words. I have great sound now and great stage. Only issue is that if I close my eyes the sound seems centred on the centre third of the windsceen. I would like this stage to cover 2/3 of the windscreen at least. But boy oh boy!!!!

I now understand why both mac and you insisted that the rears should be ditched!! Another thing.....based on the quality of install mentioned earlier there is no way I am going to let any installer touch the set up for the bi-amp till I know exactly what needs to be done. Which wire goes where which switch to be flipped, connections etc. I dont have the capability or tools to do it myself, but if i know enough about it I will get it done in front of me. Kind of like being at work :-)

MacLeod

Thats the one thing I dont like about Pioneer head units - their time alignment features. Having to input inches hurts my brain. I like the Alpines that add delay in .05 miliseconds. Much easier to dial it in for me.

Try adding delay to everything EXCEPT the sub. This will help keep the sub bass imaging up front because youll hear the sub first and the imaging cues from the mids last and that is what your brain will lock onto and youll hear it up front.

I've heard very knowledgeable people state that bi-amping is a waste of amplifiers

Anybody that says that is not knowledgeable at all. Having the ability to independently tune each driver is essential in dialing in your system for the best SQ. Thats an excellent use of an amplifier.

exalted512

MacLeod wrote: »

Thats the one thing I dont like about Pioneer head units - their time alignment features. Having to input inches hurts my brain. I like the Alpines that add delay in .05 miliseconds. Much easier to dial it in for me.

Try adding delay to everything EXCEPT the sub. This will help keep the sub bass imaging up front because youll hear the sub first and the imaging cues from the mids last and that is what your brain will lock onto and youll hear it up front.



Anybody that says that is not knowledgeable at all. Having the ability to independently tune each driver is essential in dialing in your system for the best SQ. Thats an excellent use of an amplifier.

Or you can get a tape measure?

Im curious who told you bi-amping is a waste of an amp?
-Cody

arun1963

Try adding delay to everything EXCEPT the sub. This will help keep the sub bass imaging up front because youll hear the sub first and the imaging cues from the mids last and that is what your brain will lock onto and youll hear it up front.

The last thing I do while tuning is to actually 'reduce' the gain by 0.5" on the sub.This quietens the subs a bit when everything else is dialed in and prevents the sub frequencies from bearing down on the mids and highs, while still keeping the bass upfront.

arun1963

For a novice like me, I would prefer to TA in inches. Simply becoz my ears are not at a level yet where I can time align based on my ears While going back and forth between TA and EQ settings its easy to lose the stage and in the search to get it back you can easily go further away. Its important for me to have an anchor point to back. Hence prefer 'inches' on the prs.

candaddy

I didn't totally follow your wiring info, but any wire AWG16 or better (lower number) is going to be pretty adequate. Ideally you'd want something like an oxygen free copper with many strands. This increases the conductivity and flexibility, which makes it easy to route. Speaker wire is one of those "mystic" audio subjects that really isn't much of a deal. I will say that if the wire is way too small, you will notice a lack of low-end from mids or especially subs, but 16 gauge or better is usually more than enough for mids and highs. That is roughly what comes with the kit. For subs I recommend 14 gauge or 12 gauge. It can't hurt to go bigger, but its usually just not necessary. The higher the frequency, the less wire size you need because this is an AC signal, not a DC signal, so losses are much lower at higher frequencies. It's kind of like how you run a 1 gauge wire to power your amps in your car (12 volt DC) and a 16 gauge cord to power your tuner/amp in your house (110volt AC). That statement of course assumes you're not as serious about home audio as with your car, but you get my drift.

For now, I'd say to stick with the supplied crossovers and once you've maxed that out you can start playing with the idea of using your head unit to electronically cross your speakers and eliminate the passive units from the kit.

To answer Cadenceclipse, I've run the Momo's both ways and they will sound very good either way. I feel they sound best electronically crossed, but the difference was not as large as some might lead you to believe. What electronically crossing them allows you to do, is play with the frequency at which they crossover and possibly the slopes and/or alignment if you have that capability with the electronics you might have available to you. This increases your tuning options and may increase the quality of sound for you.

I would say however that a good passive setup and a good electronic setup will not sound too much different. Most all high-end home audio setups still use passive crossover networks (albeit likely more complex ones). In my case I took the time with the install to make each system work well for me and I can't say that the electronic version was so much better that I wouldn't consider going with passives again. I've got my old Momo set up for sale right now, but I did seriously consider running them in my truck with the passives in place for awhile. If I weren't greedy for optimizing my car setup (which requires more funds :rolleyes:) I'd definitely do that, they'd be perfect for it.

arun1963 wrote: »

I love this thread. There is so much collective knowledge here. In my stock locations there is only an 9" seperation between the tweeter and mid on each side. The stock location for the mids is high up on the door panel. I thus set my time alignment from the tweeters. Like you, I use a tape and measure the distance the front L&R tweeter from the tip of my nose. Measured distance is 28" to the tweeter on my side and 45" to the one on the passenger side. The sub is in the boot facing and near the trunk lid at a distance of 76.5".

When I listen to it at this setting, the stage is dead centre in front but the sound is almost claustrophobic very tight. In order to open the sound up, I add TA to the fronts. One trick that seems to work while adding TA: front left measured = 45" front right measured =28". 45/28=1.60. Now when I increase the TA front right from 28' to 30", I increase the front left by 2"x1.6=3.2" so either 3 or 3.5" ie 48" or 48.5". This keeps the stage centred, opens out the sound and brings the bass from the sub upfront. I discovered this thru trial and error. Mac gives the scientific explanation for this earlier in the thread.

Mcleod has a lot more experience with time alignment than I do, so when he speaks about it, I listen. I'll tell you what I know about the underlying principals of it though.

There are two uses for time alignment, both are pretty similar, but for the sake of conversation we'll separate them into two. One is time alignment between drivers on one channel (right side for instance) and the other is time alignment between the two channels (right and left). For now we'll ignore the subwoofer because you seem to have a good handle on that already.

The tweeter and mid on the right side need to either be the exact identical distance from your nose to their center as possible, or they need to be time aligned somehow electronically. The same can be said for the left side, but let's stick with the right for simplicity of conversation. If you take your tape measure again and check how far the right side mid is from your nose, it should be the same 28" distance as for the tweeter on that side. If it is not, then you will not likely find that the tweeter and mid "blend" well near or on either side of the crossover frequency. This will be true no matter weather you use the passives or do it electronically. If you crossed the mid to tweeter via an active setup (like a head unit) and that active setup had time alignment, and the distance was not the same, you could correct that distance electronically and it would be as good, or nearly as good as having the two individual drivers be at the same distance. Personally, I like to get it right physically if possible rather than to rely on the electronics to band-aid it, but either way can have good results. I hope the above was clear enough and that I'm not writing it redundantly, but it sounded like you might have confused what I was talking about earlier, which is as written above.

Now the second use is how you are already using it by your description. This use will be most effective with the mids. Right/Left time alignment will do less good for the tweeters because our brains do not recognize phase with frequencies that high. That does not mean you should NOT time align tweeters (it will shift your stage around), just an interesting fact, because... The lower the frequency, the more important the left/right phase relationship becomes. The best way to get strong mid-base transients and really strong bass output from your mids, is going to be by time-aligning them as you are already doing. In other words, you need to have a mono sound emitted from them arrive at your ears at the identical time. If that does not occur, your brain will not pay attention to the sound that arrives later and it will ignore it. This is one other reason a near side speaker can sound more prevalent than a far side speaker and one reason mid-bass can end up sounding pretty weak in some cases where the distances between right/left are not close enough to equal. I.E. you will only be registering in your brain the first speaker you heard = 3db less aural input.

arun1963 wrote: »

I set the eq flat and did the TA as mentioned above. Once the sound stage was centred, I came back to the eq and tweaked one or two frequencies each for low / mid / high. (-1 on 50hz, +1 on 315, +1 on 800, +1 on 3.5kz +1 on 8khz and -1 on 12.5kz). The sound improved but the stage was diffused. The sound balance had shifted to the right. Back to TA and reduced the TA for front right. The sound came back to the centre. The vocals, chorus and most instruments were centred, however the very high frequencies (12.5 & 20khz were still located on the tweeters. To overcome this I set 12.5khz to -2 for right and -1 for left and 20hz at 0 for right and -1 for left. Kept alternating between TA and setting L / R frequencies, till something strange happened. The sound suddenly bacome quieter. I mean the sound level fell by a few decibels, the music was quiter but a little muffled. I reduced the TA on the sub ie changed the distance from 76.5" to 75.5".

BANG! It was like going to a new level of sound. Crystal clear sound, focused stage. I have never reached this level while running the rears. Never heard this quality of sound. If bi-amping and changing the placement of the tweeters can improve this further, I am at a loss for words. I have great sound now and great stage. Only issue is that if I close my eyes the sound seems centred on the centre third of the windsceen. I would like this stage to cover 2/3 of the windscreen at least. But boy oh boy!!!!

I now understand why both mac and you insisted that the rears should be ditched!! Another thing.....based on the quality of install mentioned earlier there is no way I am going to let any installer touch the set up for the bi-amp till I know exactly what needs to be done. Which wire goes where which switch to be flipped, connections etc. I dont have the capability or tools to do it myself, but if i know enough about it I will get it done in front of me. Kind of like being at work :-)

Ahhh, so we've seen the light! LOL

If your stage is perfectly centered, it would never sound wider than twice the distance the right side speaker is offset from center. I don't think there is much you can do about that (possibly by controlling reflections as has already been brushed upon earlier in the thread). In my car the center of the dash is about the limit of my far-side stage. The test CD's I mentioned previously have good tracks to accurately place drum beats, voices, etc. Like I say, if you can get them shipped to where you are, it'll be worth it to you.

I think that's enough for this post, I'll be getting carpel tunnel syndrome before long if I keep this up! LOL

cadenceclipse

i never used my TI mainly b/c, isn't it biased for seating position? sure its my system, i put all the time and $$ into it and most likely appreciate it more than my passengers, but won't that make it even worse for them? maybe i need not worry bout them or maybe optimum is having two settings on memory, or driver seat on memory and turned off when passengers are in....thanks for all the useful info dady, specially TI on mids, sounds quite tempting. take it easy for a while. u paid your dues...: )
good luk getting it done in front of u, arun. its pretty simple stuff, couple wire connections, main thing is tuning b/c of higher power u don't want to overcrank something but i'd trust u w/ no experiance over some installer who probably just wants to crank em anyway so when they blow they can say polks suk and to purchase their cheap a$$ speakers. just keep gains down till u know crossovers r set and move up slowly. i'm sure every1 else agrees...

MacLeod

Time alignment can also be used to adjust phase.

The best way I found to adjust TA is by a speaking male voice. A typical male voice runs the frequency gambit pretty wide, usually 63-5000 Hz can be easily heard.

If you dont have a good CD track of a male narrator then flip to an AM talk radio station. Turn off the tweeters and sub and tweak on the left mid's delay til the image is not only centered right but it focuses up well. It wont be perfect because each side will have some frequencies stronger than the other. Youll only be able to fix this with EQ'ing but you can get it close with TA.

After you get the mids set and if youve got your tweeters mounted away from the mids, turn off the left mid and tweet and tune the delay of the right tweeter until you hear the voice focus up and image up high. Next do the left side. Now after this is done, you play all 4 drivers and fine tune it.

Next you find something with a good fat kick drum. Metallica's And Justice for All is a good one. Listen to the initial slap on the drum and the BOOM from the sub. Add delay to ALL front speakers until this starts to image up front. Use the same delay for all 4. For instance add .5 ms to all 4 then 1.0 then 1.5 and so on.

For example, my TA settings are:

Left Tweeter - 5.80 Right Tweeter - 4.65
Left mid - 4.65 Right Mid - 3.50
Sub - 0

So my tweeters are delayed 1.15 ms from my mids and all 4 drivers are delayed 3.5 ms from the subs.

cadenceclipse

why 3.5 mac?

MacLeod

Thats what worked best. Anything more than that and it started getting into a little cancellation. Any less and it didnt sync up with the front stage as well.

eprater1

ok so i could be missing everything here but if our ultimate goal is to make it sound like the sound is coming from in front of us why not just put one mid and one tweet in the center of the dash firing straight back just as if there was a persons head on the dash singing to us???

MacLeod

Woulndt have much of a stereo effect with only one speaker. Yeah youd have a great center image but youd have no width, left or right stage.