JBL's MS-8. What does it do?

[awehmeye]

I've received lots of PM and a bunch of questions about how this thing will work, so this is more for informative purposes than a shameless plug for our product...For those of you who may be wondering about this thing, Here's a description:

MS-8 comes with the pre-amp/amp, a small display, a wireless remote control, a binaural microphone and a setup CD.

MS-8 will have 8 speaker level inputs, 8 line level inputs and an iPod input. The inputs are summed to provide a full-range 2-channel signal. If 6 or fewer inputs are required, then the last 2 can be used for an additional aux input.

There are no digital inputs. Why? Because the real benefit of digital input is "no noise". The downside to providing one is that for 99 percent of users, it's more hassle than it's worth and will cause a great deal of confusion. Not too many people understand that the connector doesn't determine the signal. What I mean is, if we put a toslink input and a user hooks up a toslink output, it will only work is the signal is compatible. DVD-Audio isn't available on a digital output, DVD signals are 48k, PCM is 44.1, home-made digital audio can be anything. The signal from tuners is often only output on the RCAs. For the vast majority of users, there is no benefit and too much opportunity for disappointment. As far as noise goes, our inputs are differential, so the commoon mode noise rejection is super high. There won't be any noise.

There are 8 input channels, so the 8 speaker level inputs and 8 line level inputs are basically in parallel. You can use any combination.

Once the signals have been combined and un-EQed (for a flat 2-channel signal), the signal is processed with Logic7. That provides signal steering for a center channel (if you have one--if not, no problem) and processing for side and rear channels. L7 works on any 2-channel source and is our version is written for cars rather than live-in rooms, so it sounds MUCH better than any of the encoded formats in a car. The 2-channel downmix of any encoded DVD or DVD-A disc will play back in full surround. If good-old 2-channel is what you want, L7 is defeatable and the channels are fully configurable (there are 8 output channels and they can be pre-amp channels or powered channels--20W x 8 at 4 ohms, 30W at 2 ohms). You can have 3-way front, a center and a sub, 2-way front, rear and a sub...whatever you want to do.

The electronic crossover that's built in is fully configurable. You can assign any channel to be anything and it includes an EZ setup mode and an advanced mode. In EZ setup, you tell each channel the speaker location (front right, for example), then you tell it what speaker is connected (6" full-range). It sets the crossover point. In advanced mode, you tell the channel the location (right front) and then assign a filter type (HP, LP, BP) and then you set the filter frequency (you can assign any value between 20 at 20kHz) and the slope (1st-4th order).

After the crossover setup is completed, you move on to the EQ. You put on the microphones (they look like airline headphones but contain mics instead of speakers) and insert the CD. The display will give you some instructions to sit in the driver's seat and look at the left mirror and press "go". the unit will make a quick sweep of all 8 output channels. Then it will ask you to look forward and will make another sweep. Finally, it'll ask you to look to the right--another quick sweep. You can measure only the driver's seat or up to 4 seats. After the measurements are made (takes about 5 minutes) the unit will calculate the frequency response, level and arrival time for all 8 channels in each seat and crunch some numbers (another 30 seconds or so). It auto-tunes the car with 48 measurements per seat (up to 4 seats). It will output a tuning optimized for the driver, passenger, compromise between driver and passenger and one for the rear seats. If you use a center channel, both front seats will sound the same and the image will be great for rear seat passengers too.

After the auto-tuning is done, it will allow you to change the target curve. You can call up a 31-band EQ tool and make whatever changes you want. Unlike a regular EQ, you don't have to find an RTA and tune the car with the EQ, you just draw the curve you want to hear and press "go" and it does the work in implementing your curve. Then you can switch back and forth between your curve and the automatic one and continue making changes until you're satisfied. The curve you draw will always be adjusted in level so that the maximum number of bits are available to describe the signal (optimized for dynamic range). Once you save the curve, you can access any of the settings optimized for any seat using the remote control and the display.

You can turn Logic7 on and off, adjust the level of the center channel, use a balance control, fader, 3 or 11-band graphic EQ or adjust the level of the bass. THe bass control isn't a gain control for the subwoofer output, it's a filter that works with the crossover and applies the right amount of bass to ALL channels so the illusion of bass up front isn't destroyed when you turn up the bass.

Answers to some likely questions:

1. You don't have to use the unit's volume control. You can use the one in the head-unit if you want to.
2. Maximum input voltage on the RCAs is 2V and 15V on the speaker level inputs. The signal is converted directly into digital after the preamp buffer, so a high signal level is far less important in this device than in conventional ones. The input is fully differential, so there won't be noise. I suggest speaker level connections because they are COMPLETELY isolated from ground.
3. The automatic EQ isn't exactly parametric or graphic. It's a very powerful algorithm that works on the impulse response to adjust both time and frequency response. It's amazing and does in about 30 seconds what I can do with an 80 band parametric EQ, crossover, time alignment and a serious analyzer in about 3 days.
4. The display doesn't have to be mounted. If you don't want iPod control or the ability to adjust after setup, you can unplug the display and use MS-8 as a "black box".
5. The unit is small--about 8.5" x 11" x 2.5"
6. Price will be about $800...TBD
7. The software is updatable via USB and a PC.

It does what all other OEM integration tools do and what every other DSP (EQ, Crossover, Time alignment, 7.1) processors do, but it sounds better, is easier to use, is less expensive and is far more advanced in terms of DSP power. Best of all, it's a tool you can be successful with, rather than a whiz-bang collection of filters and adjustment possibilities that require a PhD in acousitcs to use.

[Jason Ewing]

Who thinks we need a group buy???? HINT HINT Andy

[Matt_Sibley]

Andy,

From what I read in this post the center is almost a necessity to make the processor perform to its full potential. Gary said that he has had this processor in his Regal since 2005 doing some prototype testing for you guys. I know Gary didnt run a center channel and his car sounded great from either the driver or passenger position.

Perhaps you and some of the others on here can help me and make some recommendations for my setup. I have a 1997 Ford F150 and will be getting a 2007 or 2008 Tahoe within a year or so. Either vehicle has a rather large dash, high seating position and is somewhat wide.

I'm looking at running Focal 100KP's(4'' and tweeter) with the 165KBE(6.5'' bass extension kit) and then using another 100KP as a center. The amplifiers I plan to use if I do the center and use this processor are 2 McIntosh MCC404M's. One will be used as a 2-channel 400x2@4ohm on the left and right 3 ways, the front channels of the other will be used on the center and the rear channels used in stereo on a set of rear speakers(400x1, 100x2). I also plan to use the MCC301M for a single 27V2 subwoofer. The 4'' and tweets will be in the Apillars with the 6.5'' midbass drivers in the kickpanels. I am going to rework the dash and attempt to get the center in there as well as the sub.

My main question is: Will the center and rear speakers provide a huge benefit? Or would it be better to just run the 3 ways and a sub and scratch the center and rear speakers?

Another question I haven't seen that has sparked my interest: After the phase correction/auto eq portion has taken place, one is allowed to go in and manually change the eq curve. Upon changing this curve can you rerun the phase correction processing to correct for any phase issues the manual eq adjustment may have caused? Thanks for your help!

[Matt_Sibley]

Originally Posted by Matt_Sibley

Andy,

From what I read in this post the center is almost a necessity to make the processor perform to its full potential. Gary said that he has had this processor in his Regal since 2005 doing some prototype testing for you guys. I know Gary didnt run a center channel and his car sounded great from either the driver or passenger position.

Perhaps you and some of the others on here can help me and make some recommendations for my setup. I have a 1997 Ford F150 and will be getting a 2007 or 2008 Tahoe within a year or so. Either vehicle has a rather large dash, high seating position and is somewhat wide.

I'm looking at running Focal 100KP's(4'' and tweeter) with the 165KBE(6.5'' bass extension kit) and then using another 100KP as a center. The amplifiers I plan to use if I do the center and use this processor are 2 McIntosh MCC404M's. One will be used as a 2-channel 400x2@4ohm on the left and right 3 ways, the front channels of the other will be used on the center and the rear channels used in stereo on a set of rear speakers(400x1, 100x2). I also plan to use the MCC301M for a single 27V2 subwoofer. The 4'' and tweets will be in the Apillars with the 6.5'' midbass drivers in the kickpanels. I am going to rework the dash and attempt to get the center in there as well as the sub.

My main question is: Will the center and rear speakers provide a huge benefit? Or would it be better to just run the 3 ways and a sub and scratch the center and rear speakers?

Another question I haven't seen that has sparked my interest: After the phase correction/auto eq portion has taken place, one is allowed to go in and manually change the eq curve. Upon changing this curve can you rerun the phase correction processing to correct for any phase issues the manual eq adjustment may have caused? Thanks for your help!

Bump...

[Slick]

A center channel isn't necessary with the MS-8, it's helpful if you want the same soundstage from both seats, without the center there will be some compromise in one seat or the other but it's not necessary (I would assume most will make the drivers seat the first choice and compromise on the passenger seat).

[Matt_Sibley]

I guess I"m new to the forum and just slightly confused. It appears that most of this topic is also under Richard Clark on Audio but that forum is archived and will not let me post. However, certain people have replied to it there that haven't here. Am I doing something wrong?? Thanks.

[Rob M]

Originally Posted by Matt_Sibley

I guess I"m new to the forum and just slightly confused. It appears that most of this topic is also under Richard Clark on Audio but that forum is archived and will not let me post. However, certain people have replied to it there that haven't here. Am I doing something wrong?? Thanks.

I copied this thread over from the archived RC on Audio forum, all the replies there should be in this thread, too. Are there any in particular you found missing?

[Matt_Sibley]

I just saw where Andy had replied to most of the posts there but I didnt see my post directed toward him in that part of the forum. But I assume we should use this part now? THanks.

[awehmeye]

The center is necessary to provide correct imaging in all seats simultaneously IF the pathlengths are not equidistant. I definitely recommend a big cnter channel speaker. I also recommend using rear and side speakers, but only rear or side is probably sufficient for most systems and the benefit of the additional pair is very subtle. IF you want to build a 5.1 system with a bi-amped front stage, MS-8 has enough channels to support it. If you want a full 7.1 with a bi-amped or tri-amped front, then send the outputs that you designate as front from MS-8 to an additional crossover or amplifiers with crossovers built in to divide the signal for the front speakers.

The sub DOES NOT NEED TO BE INSTALLED IN THE FRONT! Put it in the back and focus on the center channel.

Finally, yes, you can re-EQ after MS-8 has done its work. You get a 31-band drawing tool to make a new curve. MS-8 takes care of the rest.

[Ge0]

Originally Posted by awehmeye

The center is necessary to provide correct imaging in all seats simultaneously IF the pathlengths are not equidistant. I definitely recommend a big cnter channel speaker. I also recommend using rear and side speakers, but only rear or side is probably sufficient for most systems and the benefit of the additional pair is very subtle. IF you want to build a 5.1 system with a bi-amped front stage, MS-8 has enough channels to support it. If you want a full 7.1 with a bi-amped or tri-amped front, then send the outputs that you designate as front from MS-8 to an additional crossover or amplifiers with crossovers built in to divide the signal for the front speakers.

The sub DOES NOT NEED TO BE INSTALLED IN THE FRONT! Put it in the back and focus on the center channel.

Finally, yes, you can re-EQ after MS-8 has done its work. You get a 31-band drawing tool to make a new curve. MS-8 takes care of the rest.

Andy,

This is my first post on this forum but have been lurking for weeks reading up on anything regarding the MS-8. I was brought to this forum from ECA for this exact reason.

I've been following all threads I can find regarding this product and cannot find my answer.

You recommend using a BIG center channel. Please elaborate.

I am like numerous potential customers. I will implement this processor to improve a factory system. The reason being that I want to keep the factory head (contains navigation, vehicle control and info, etc..). I want to keep the vehicle as stock looking as possible. This is a daily driver that for my own reasons can't trick out with gear and custom install. So, I don't want to cut a big hole in my dash to place a center channel speaker. However, I do want to utilize the logic7 processor.

What are the requirements for a center channel to make logic7 work? Say I wanted to hide a small speaker somewhere in the center dash console? Will a simple tweeter work to some degree of satisfaction? A small midrange? What is the low frequency limit cut-off? What type of power do I need to supply to it in relation to the fronts and rears? Could the MS-8 power this speaker?

It would be helpful to me, and many others, to go into some detail.

Thanks,

Ge0