View Full Version : Setting up a JBL MS-8

06-28-2011, 11:10 AM
I am having some difficulty understanding what settings to use while setting up a new system.

Audison 5.1k amp
Kenwood 9980 head unit
Hertz Mile ML 280 tweeters
Hertz ML 1600 woofers
(optional) Hertz Crossover

The problem I am seeing is, you are suppose to keep the JBL at -21db if using a external amp source.

By doing this the volume output I am getting is lowered than if i were to just plug the rca's directly into the amp.

Also the slope and Xover as this is a new setup and not familiar to what to run these speakers at.

The tweeters are being ran off axis

06-28-2011, 12:00 PM
Don't know if you know about it or not but there's a fairly lengthy and in-depth thread over on the DIYMA forum about the MS-8 and the guys at JBL who are in charge of the product are very regular contributors on that thread. Andy, the main JBL guy, seems to be very helpful and open to answer any questions. Here's a direct link: JBL's MS-8 processor! - DIYMA.com - Scientific Car Audio - Truth in Sound Quality (http://www.diymobileaudio.com/forum/diyma-sq-forum-technical-advanced/8257-jbls-ms-8-processor.html). I hope that's OK to do here. I haven't been a part of this forum for very long. You should definitely check it out. It is very helpful. Lots of great discussion/answers on the MS-8.

Before you check out that forum, though, the way I understand it is that you do the calibration at -21db but after calibration you should jump the MS-8 level up to between -10db and -6db. Something about the calibration at that lower level gets better results but then listening levels can be higher. As far as slope and Xover settings for the speakers you are using, you should be able to get a better understanding of where to try them out after reading the MS-8 thread on DIYMA. When I had mine I used the defaults and then played from there just to see if there was any noticeable difference to me. Don't let this influence you at all, but I couldn't get it to sound as good as I wanted it to so I ended up removing it and selling it. I know a number of people that swear by the device, though.

Good luck!

06-28-2011, 03:27 PM
Here is what I have so far

Tweeters set to 45 HZ at 6db/oct "sounds not filled in"

Woofers set Lo/Hi Xover 80Hz "clipping at higher volumes" with 6 db/oct

Woofers at 100Hz and 12 db/oct still clipping.

Where do I need to go from here? Anyone?

06-28-2011, 03:29 PM
one of my friends who is all into going active all day every day with every last type of EQ out there had a hard time setting up the ms8...got rid of it after maybe 2 weeks

06-28-2011, 05:53 PM
"Tweeters should be high-passed somewhere around 3000 - 4000 Hz. Check the manual and find out what the passive x-over uses and start with that. Make sure you use a cap to protect them from turn-on and off thumps.

Woofers high-passed at around 40 - 60 Hz, depending on how low they can play and how low you want them to play. I would do 60 Hz to start with.

I would try 24dB/oct slopes to begin with."

Tried this and was not getting any mids where should I go from here?

06-29-2011, 10:50 AM

06-29-2011, 12:41 PM
Come to find out it was a switched rca cable.

07-04-2011, 04:30 AM
You want to have it at the lower volume level because it's supposed to be calibrated at 2volts of input. You can turn it back up after that. I got rid of it because I just didn't have the system for it, works best with rears and a center channel and I have neither.