[kaigoss69]

The first crossover it asks for is the sub sonic. If you run a true subwoofer, this can be set very low, but in your case it needs to be set higher to protect the underseats from over excursion.

[squidlyboy]

Originally Posted by kaigoss69

The first crossover it asks for is the sub sonic. If you run a true subwoofer, this can be set very low, but in your case it needs to be set higher to protect the underseats from over excursion.

Odd that it only limits the freq range to only be from 20hz-100hz though

What if your two-way fronts are component mid (on its only channel), and the tweeter (also on its own channel)? A subsonic HP doesn't seem like it would make sense in that situation. Or at least the freq xo would be much higher for the high pass

[kaigoss69]

Originally Posted by squidlyboy

Odd that it only limits the freq range to only be from 20hz-100hz though

What if your two-way fronts are component mid (on its only channel), and the tweeter (also on its own channel)? A subsonic HP doesn't seem like it would make sense in that situation. Or at least the freq xo would be much higher for the high pass

If you have a system that requires a subsonic of over 100hz, then you won't be looking to upgrade it with a MS-8.

[jeffb335]

I think you are looking at the sub sonic filter wrong? Its a high pass filter that is set at the LOW end of the sub range....its purpose is to limit how low your system will go as to not waste power on frequencies that are lower than your system can produce AND to protect your drivers from over-excursion when playing extremely low frequencies.

subsonic filters are typically exactly that.....sub-sonic....in a properly set up system this is set below the lowest point at which your sub can go with authority, and typically corresponds to a point around which we can no longer hear it anyway, usually around 20-30hz in most systems, going any lower than that is just wasting power, causing distortion, making heat, roasting voice coils.....

This of course varies but since its the bottom of the sub range its always going to be pretty low. With a 10" or bigger sub, probably around 20-30hz, with the stock underseats maybe a bit higher, 40-50hz. Any higher than that though and the missing frequencies are going to start to be pretty audible....

[squidlyboy]

Are we talking about the same thing?

I'm not talking about setting up the 'Sub' (first one in Input Selection that is set up). I selected 'None' for that. For that, i know it mentions the sub-sonic frequency. That's not the one i'm referring to....

I'm talking about the Fronts. For this latest configuration, i chose a Front 2-way instead of one-way. For a front one-way, it doesn't ask me about any crossover freq. For the two-way, it starts by asking 'Front High/Low Crossover' and its this one that is pegged between 20hz-100hz. Why does it assume the cross-over freq between front high and front low would be down at that range? i.e. doesn't make sense in the case of a mid and tweeters running on separate channels...

[jeffb335]

yeah, maybe....

So I looked back at your post and everything looks right (or close enough) except the crossover in bold below:

Input Settings:
Sub - none
Front - 2-way (1st xo: 70hz/12, 2nd xo: 170hz/24)
Center - none
Side - 1-way (xo: 170hz/24)
Rear - none


Basically in the above configuration you are going to have little sound below 70hz.....thats ok if you are running a separate sub but you aren't....so you need the underseats to play much lower. Set it around 40hz but use a steeper slope like 18 or 24 and see how it sounds, depending on the music you listen to you could go lower and shallower with the slope but this is a good starting point. I ran mine in this configuration for a while when I had my sub out of the car and I was able to get fantastic results.

Also, about your volume level....after calibrating did you turn the MS-8 back up? While you might be calibrating it with it turned down, you should be running it around -6db to -12db for regular listening. Keep in mind you are also running everything through an amp....so you have the head unit volume (which the MS-8 will prompt you to set to the correct level when you start), the MS-8s output level, and the amps gain control. ALL of these must be set correctly in order to get a volume range that makes sense. If you are maxing out the head unit volume then either the MS-8 is still turned down, or the amp gains are not correctly set.

[kaigoss69]

I'm sure the difference in output volume has something to do with the fact that the HiFi HU outputs ~5V balanced and the MS-8 outputs ~2V unbalanced. But this is not a problem, because that's what you have adjustable amp gains for.

[kaigoss69]

... also, input voltage switch must be set to LOW.

[vithy]

kaigoss69,

My JL XD700/5 arrived yesterday. And installed it. But now just running the SUB L/R (MS8 channels 7/8).

I was planning to setup of 1/2 channels (MS8 Ch. 1/2) for Front doors, 3/4 (MS8 Ch. 5/6) for underseats, SUB L/R (MS8 Ch. 7/8) for the trunk sub and run the read door with MS8 channels 3/4.

Question is I have.
1) I turned off all Filters on JL (All channels) My understanding is, since my crossovers are going to be done by MS8, I can turn them off right?

2) How do I determine the gains for all channels? Which position do I leave it at?

3) Do I have to level match between MS8 channels and JL channels?

Please let me know.

Thanks
Vithy

[kaigoss69]

Originally Posted by vithy

kaigoss69,

My JL XD700/5 arrived yesterday. And installed it. But now just running the SUB L/R (MS8 channels 7/8).

I was planning to setup of 1/2 channels (MS8 Ch. 1/2) for Front doors, 3/4 (MS8 Ch. 5/6) for underseats, SUB L/R (MS8 Ch. 7/8) for the trunk sub and run the read door with MS8 channels 3/4.

Question is I have.
1) I turned off all Filters on JL (All channels) My understanding is, since my crossovers are going to be done by MS8, I can turn them off right?

2) How do I determine the gains for all channels? Which position do I leave it at?

3) Do I have to level match between MS8 channels and JL channels?

Please let me know.

Thanks
Vithy

Vithy, yes you turn all the amp crossovers to the off position. I am not a fan of mixing ms-8 and aftermarket amp channels exactly due to the point you already made.

The processor likes to hear roughly the same volume from all channels, so if the fronts are way higher, then it will try to boost the rears too much.

Better way to do it is you level match. Start with all amp gains at minimum (all the way counterclockwise). Listen for respective sweep volumes during calibration and make adjustments if necessary, then recalibrate. Best way to do it is using hidden menu and output identification test. This requires you to read and understand the procedure before you do it, since you can damage your speakers if you are not careful. Also requires a way to measure the tones with your smartphone. Plenty of info over at Diyma.

You may get this to work or you may get frustrated as hell. If you ask me forget about the sides and just run the front speakers and the trunk sub. It sounds the best.

[squidlyboy]

sorry.. been slammed with work today, then dinner with the wifey tonight - just getting back to it now

Originally Posted by jeffb335

Input Settings:
Sub - none
Front - 2-way (1st xo: 70hz/12, 2nd xo: 170hz/24)
Center - none
Side - 1-way (xo: 170hz/24)
Rear - none

Basically in the above configuration you are going to have little sound below 70hz.....thats ok if you are running a separate sub but you aren't....so you need the underseats to play much lower. Set it around 40hz but use a steeper slope like 18 or 24 and see how it sounds, depending on the music you listen to you could go lower and shallower with the slope but this is a good starting point. I ran mine in this configuration for a while when I had my sub out of the car and I was able to get fantastic results.

Yup much better!

Originally Posted by jeffb335

Also, about your volume level....after calibrating did you turn the MS-8 back up? While you might be calibrating it with it turned down, you should be running it around -6db to -12db for regular listening. Keep in mind you are also running everything through an amp....so you have the head unit volume (which the MS-8 will prompt you to set to the correct level when you start), the MS-8s output level, and the amps gain control. ALL of these must be set correctly in order to get a volume range that makes sense. If you are maxing out the head unit volume then either the MS-8 is still turned down, or the amp gains are not correctly set.

Funny... when i was getting out of my car this morning at work, just before heading into the building, i thought about this for awhile, and realized there was no reason to leave the volume at the calibration level, so i quickly shot it up to 0db. I still had my amp gains set to minimum though. When i left work today and listened for the first time to this change, wow.. it was like my old system had returned

Originally Posted by kaigoss69

I'm sure the difference in output volume has something to do with the fact that the HiFi HU outputs ~5V balanced and the MS-8 outputs ~2V unbalanced. But this is not a problem, because that's what you have adjustable amp gains for. ... also, input voltage switch must be set to LOW.

i doubled checked and yes, set to low.

Originally Posted by kaigoss69

Ok squidly, do this:

- set the front as 2-way, no sub
- subsonic 50hz 24db/oct, low/hi 200/24
- sides 100/24
- set all xd gains at 12 o'clock (for now)
- calibrate at -35db (if sweeps seem louder than conversation volume, adjust lower and recalibrate)
- Only run sweeps for drivers seat
- unplug mic before you select "done"

Let me know how it sounds. You may have to play with the amp gains for the underseats to get it dialed in correctly.

This is the best configuration yet! Seems like setting the front's as 2-ways, proper cross-overs for the fronts, and xd gains higher than minimum has done the trick. I was wondering why you all calibrate at such low levels, but when i put my xd gains at 12 o'clock, i had to push my calibration level down to -45db to get it to conversation level haha. Man... I feel like NOW i can start to do fine tuning, using this base setup as my starting point! THANKS SO MUCH FOR YOUR VALUABLE INPUT!!!

Results/Observations
1. i feel like my old system(with just the xd800) has returned and is slightly better. since i just got it dialed in tonight, its hard for me to quantify and articulate right now "how" better. I'll need a week to process all of this and do some fine tuning. But initial impressions - there's a sense that the the music is "deeper" and i feel more enveloped in it... all around. Its really a pleasure to listen to

2. for kicks i also calibrated the passenger side afterwards, and did a quick A-B comparison back and forth sitting in the driver's seat listening to both. i can experience now how the balancing works as the ms-8 calibrates for where the listener is sitting. Listening to the passenger setting in the driver's side, i can sense the shift in the tone ranges and it definitely feels more lopsided and unbalanced, esp the vocals. It feels like its right in my face. Then switching back to the driver settings, all the balance and imaging comes back in a real natural way. Very cool.

3. I'm still at a loss for why deleting the center channel makes such a huge difference. With it in during calibration, the result was AM clock radio sound. With it out, the bass was back ... a little overbearing, but back. I will do more testing with it back in tomorrow to see what can be done about adding it back. I know most people hate the thing, but i would like to see if adding a tweeter to might enhance the sound. I would really hate to lose it, esp since i spent good money upgrading it to the BSW S-1 mid.

4. In the coming days, i'll probably do some RTA to see if i have the dreaded mid-bass hole in the FR.

5. After calibrating at -45db (and having the amp gains all at 12 o'clock), i notice post-calibration i have to bring the ms-8 system volume to around -20db to -15db get to the volume levels to same place as before with just the xd800 - i.e. HU volume set to 50% . But when i set the ms-8 to those levels, a very noticeable hiss gets introduced into the system. i have to leave the ms-8 at around -25db to get rid of it. i'll probably play with the combo over the weekend to keep the noise floor low enough.

---

All this has put a big smile back on my face. I wasn't ready to accept the fact that an extra $300 in audio equipment was going to make it sound worse. I will be looking to upgrade the underseats later with some SWS-8's or better and hope i can start with this base config and add to it without major upheaval.

I'm still on the fence about a trunk sub. I hear lots of folks have to put down their ski doors in order to hear it. That just sounds weird to me to have to go through that level of hassle to hear your music. If i can't get good returns leaving the back seats in place, i'm going to drop the trunk sub idea. Would love to hear any inputs on that.

[vithy]

I guess you don't regret the investment on MS8, as you though you might have earlier. Trust me MS8 brings better imaging and EQ to the overall sound. I don't think just adding an AMP is enough.. but thats just me...

I was on the fence like you on the Trunk SUB. Again trust me, do it!!!.... You will gain the LO's that you lack from underseat woofers. With 3 way front setup, you can make your underseats mid/sub sound better. You can sort of blend the sound with your trunk SUB. And yet keep the OEM underseat woofer. If and when you calibrate it properly you don't need to open up your "ski doors". I don't even feel like I have a sub in the turnk, but yet they do work and blend well. Do what kaigoss69 suggested on the underseat woofers. Reverse the polarity on them and add the trunk sub, you wont even feel the trunk sub.

Originally Posted by squidlyboy

sorry.. been slammed with work today, then dinner with the wifey tonight - just getting back to it now


Yup much better!


Funny... when i was getting out of my car this morning at work, just before heading into the building, i thought about this for awhile, and realized there was no reason to leave the volume at the calibration level, so i quickly shot it up to 0db. I still had my amp gains set to minimum though. When i left work today and listened for the first time to this change, wow.. it was like my old system had returned


i doubled checked and yes, set to low.



This is the best configuration yet! Seems like setting the front's as 2-ways, proper cross-overs for the fronts, and xd gains higher than minimum has done the trick. I was wondering why you all calibrate at such low levels, but when i put my xd gains at 12 o'clock, i had to push my calibration level down to -45db to get it to conversation level haha. Man... I feel like NOW i can start to do fine tuning, using this base setup as my starting point! THANKS SO MUCH FOR YOUR VALUABLE INPUT!!!

Results/Observations
1. i feel like my old system(with just the xd800) has returned and is slightly better. since i just got it dialed in tonight, its hard for me to quantify and articulate right now "how" better. I'll need a week to process all of this and do some fine tuning. But initial impressions - there's a sense that the the music is "deeper" and i feel more enveloped in it... all around. Its really a pleasure to listen to

2. for kicks i also calibrated the passenger side afterwards, and did a quick A-B comparison back and forth sitting in the driver's seat listening to both. i can experience now how the balancing works as the ms-8 calibrates for where the listener is sitting. Listening to the passenger setting in the driver's side, i can sense the shift in the tone ranges and it definitely feels more lopsided and unbalanced, esp the vocals. It feels like its right in my face. Then switching back to the driver settings, all the balance and imaging comes back in a real natural way. Very cool.

3. I'm still at a loss for why deleting the center channel makes such a huge difference. With it in during calibration, the result was AM clock radio sound. With it out, the bass was back ... a little overbearing, but back. I will do more testing with it back in tomorrow to see what can be done about adding it back. I know most people hate the thing, but i would like to see if adding a tweeter to might enhance the sound. I would really hate to lose it, esp since i spent good money upgrading it to the BSW S-1 mid.

4. In the coming days, i'll probably do some RTA to see if i have the dreaded mid-bass hole in the FR.

5. After calibrating at -45db (and having the amp gains all at 12 o'clock), i notice post-calibration i have to bring the ms-8 system volume to around -20db to -15db get to the volume levels to same place as before with just the xd800 - i.e. HU volume set to 50% . But when i set the ms-8 to those levels, a very noticeable hiss gets introduced into the system. i have to leave the ms-8 at around -25db to get rid of it. i'll probably play with the combo over the weekend to keep the noise floor low enough.

---

All this has put a big smile back on my face. I wasn't ready to accept the fact that an extra $300 in audio equipment was going to make it sound worse. I will be looking to upgrade the underseats later with some SWS-8's or better and hope i can start with this base config and add to it without major upheaval.

I'm still on the fence about a trunk sub. I hear lots of folks have to put down their ski doors in order to hear it. That just sounds weird to me to have to go through that level of hassle to hear your music. If i can't get good returns leaving the back seats in place, i'm going to drop the trunk sub idea. Would love to hear any inputs on that.

[vithy]

kaigoss69,

Finally setup the amp for the front stage and MS8 for rear doors.

I followed JL's advice on Gain Setting

"Simplified Gain Setting: This XDv2 Series amplifier makes setting the gain level of the amp via the input sensitivity control very simple. All you need is Digital AC Voltmeter and a CD Test Disc with a sine-wave test-tone recorded at 0 dB reference level in the frequency range to be amplified for that set of channels (50 Hz for subwoofers, 1 kHz for a midrange application). Each pair of inputs has a separate Input Sensitivity control."

Used 17V for the doors/underseat and 26V for SUB gain as per recommendation for 4 ohm speakers.

After first calibration, used the Test Menu on MS8 to level match my front stage with rear doors. Did a re-calibration as 3 way. And everything worked fine... I also reversed the underseat polarity and proper polarity on the trunk sub. Additional power by external amp definitely helps bring out the potential of the the underseat woofers, They sound so much better. Lots of punch without any distortion/boomynes. Wow... I never imagined OEM speakers could ever bring this much detail. I'm even thinking not to upgrade them but add an after market tweeter and crossover to the system (we'll see. I sure i will upgrade)

For some reason I didn't like the xover of the trunk sub at 24db/oct, I tried 18 and 12. Finally decided on 12db/oct for the trunk sub.


Thank you kaigoss69 for all your advice and help.

Originally Posted by kaigoss69

Vithy, yes you turn all the amp crossovers to the off position. I am not a fan of mixing ms-8 and aftermarket amp channels exactly due to the point you already made.

The processor likes to hear roughly the same volume from all channels, so if the fronts are way higher, then it will try to boost the rears too much.

Better way to do it is you level match. Start with all amp gains at minimum (all the way counterclockwise). Listen for respective sweep volumes during calibration and make adjustments if necessary, then recalibrate. Best way to do it is using hidden menu and output identification test. This requires you to read and understand the procedure before you do it, since you can damage your speakers if you are not careful. Also requires a way to measure the tones with your smartphone. Plenty of info over at Diyma.

You may get this to work or you may get frustrated as hell. If you ask me forget about the sides and just run the front speakers and the trunk sub. It sounds the best.

[kaigoss69]

Squidly, if you get hiss your amp gains are probably too high. In the end you want to keep the MS-8 volume at a constant -6db, and just use the HU volume. Set the amp gains such that you will get the loudest volume level you would ever want to listen to at 75% HU volume. So reduce amp gains (all by the same amount), recalibrate, set MS-8 volume to -6db and turn up HU to 75%. If it is too loud, and you have hiss, turn amp gains down again and recalibrate, and repeat procedure as often as you need to find the perfect balance.

[kaigoss69]

Vithy, if it sounds better leave it there but be aware that a 12db crossover will let the underseats play a LOT more low frequency content than a 24db crossover and you could be overpowering them at high volume levels, so be careful!

[vithy]

Yes. I will try to bump it up to 18 and see. If not switch it back to 24 and increase the SUB gain. I think i just got used to a little bit of thump the last few weeks while I had the system unproperly configured. I think I will get used to it at 24.

Do you recommend upping the SUB gain? or does it mess up the EQ?

Thanks

Originally Posted by kaigoss69

Vithy, if it sounds better leave it there but be aware that a 12db crossover will let the underseats play a LOT more low frequency content than a 24db crossover and you could be overpowering them at high volume levels, so be careful!

[squidlyboy]

Originally Posted by vithy

I guess you don't regret the investment on MS8, as you though you might have earlier. Trust me MS8 brings better imaging and EQ to the overall sound. I don't think just adding an AMP is enough.. but thats just me...

Thanks vithy .. for referring me over to this thread and for everyone's great input, esp kaigoss

Originally Posted by vithy

I was on the fence like you on the Trunk SUB. Again trust me, do it!!!.... You will gain the LO's that you lack from underseat woofers. With 3 way front setup, you can make your underseats mid/sub sound better. You can sort of blend the sound with your trunk SUB. And yet keep the OEM underseat woofer. If and when you calibrate it properly you don't need to open up your "ski doors". I don't even feel like I have a sub in the turnk, but yet they do work and blend well. Do what kaigoss69 suggested on the underseat woofers. Reverse the polarity on them and add the trunk sub, you wont even feel the trunk sub.

One thing about this reverse polarity thing still confuses me though.. I didn't think it was needed anymore since he applied the Andy W trick of attaching the sub to the front as a 3-way so that it is included in the T/A. I read through the Scooby-Do thread and he said this halfway down:

Originally Posted by kaigoss69

"To achieve seamless integration between speakers in adjacent passbands, they MUST be phase aligned at the crossover frequency. The easiest, and most accurate way of achieving this is through time alignment."

From what i understand now, T/A achieves the same thing as reverse polarity by delaying the sound waves so that they arrive at the same time. Its just a more sophisticated way of doing it - e.g. DSP instead of swapping +/- wires. Plus switching speaker wires (reversing polarity) will only always shift phase exactly 180 degrees, while DSP T/A algorithm is (should be) able to fix any arbitrary phase shift for optimal phase alignment, correct?

If so, why would you still need to do it?

Thats like asking folks to remove the leaves from the branches first before you plan on chopping down the tree anyways

And besides... reversing polarities will fix the problem perfectly only if you happen to be exactly 180 degrees out of phase. If you are only 90 degrees out of phase, you will still be 90 degrees out of phase after swapping.

[squidlyboy]

Originally Posted by kaigoss69

Squidly, if you get hiss your amp gains are probably too high. In the end you want to keep the MS-8 volume at a constant -6db, and just use the HU volume. Set the amp gains such that you will get the loudest volume level you would ever want to listen to at 75% HU volume. So reduce amp gains (all by the same amount), recalibrate, set MS-8 volume to -6db and turn up HU to 75%. If it is too loud, and you have hiss, turn amp gains down again and recalibrate, and repeat procedure as often as you need to find the perfect balance.

Thanks... thats perfect. With just the XD800 in place previously, 75% HU was about the place where it started the headache-inducing volume :-) so this is what i'm used to previously. For the hiss, i'll bring the xd800 amp gains lower to like 9 o'clock like what they were previously so that i can push the ms-8 volume higher. Makes sense.

[jeffb335]

Yes, to minimize noise you always want to start at the source and maximize the distortion free output of each device as you move downstream....roughy 75% is the rule of thumb on most head units, -9db on the MS-8 is JBLs recommendation as I recall (although anywhere between -6db and -12db is probably fine), then set the amp gain to wherever it needs to be to reach a reasonable "maximum" listening level....on that amp that will be a pretty low gain setting. In this configuration the amp will be amplifying mostly signal, not noise floor.

FYI, in my car the noise floor is inaudible....Dynavin N6 headunit>MS-8>amps.

[squidlyboy]

BTW... what calibration apps and other rta/audio tool apps do you all recommend? I took a look at the JL Audio Tools, which apparently used to be free, but now its $25.

The JL Audio Tool package seemed pretty cool as it had an SPL meter, speaker polarity test, along with all the normal RTA stuff. Seeing if there is an equivalent for free before i pull the trigger on this ...

[squidlyboy]

Originally Posted by jeffb335

Yes, to minimize noise you always want to start at the source and maximize the distortion free output of each device as you move downstream....roughy 75% is the rule of thumb on most head units, -9db on the MS-8 is JBLs recommendation as I recall (although anywhere between -6db and -12db is probably fine), then set the amp gain to wherever it needs to be to reach a reasonable "maximum" listening level....on that amp that will be a pretty low gain setting. In this configuration the amp will be amplifying mostly signal, not noise floor.

FYI, in my car the noise floor is inaudible....Dynavin N6 headunit>MS-8>amps.

Thanks! thats the "picture" i was looking for :-) its crystal now

[vithy]

So with 3 way front setup, T/A is achieved for SUB on Lo's? I didn't know what.

Well. I still think you should go for a trunk SUB and keep the underseat OEM woofers, instead of swapping them.

Originally Posted by squidlyboy

Thanks vithy .. for referring me over to this thread and for everyone's great input, esp kaigoss



One thing about this reverse polarity thing still confuses me though.. I didn't think it was needed anymore since he applied the Andy W trick of attaching the sub to the front as a 3-way so that it is included in the T/A. I read through the Scooby-Do thread and he said this halfway down:



From what i understand now, T/A achieves the same thing as reverse polarity by delaying the sound waves so that they arrive at the same time. Its just a more sophisticated way of doing it - e.g. DSP instead of swapping +/- wires. Plus switching speaker wires (reversing polarity) will only always shift phase exactly 180 degrees, while DSP T/A algorithm is (should be) able to fix any arbitrary phase shift for optimal phase alignment, correct?

If so, why would you still need to do it?

Thats like asking folks to remove the leaves from the branches first before you plan on chopping down the tree anyways

And besides... reversing polarities will fix the problem perfectly only if you happen to be exactly 180 degrees out of phase. If you are only 90 degrees out of phase, you will still be 90 degrees out of phase after swapping.