WakeWorld - Line driver questions

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- - Line driver questions (http://www.wakeworld.com/forum/showthread.php?t=224885)

Was looking for some answers on line drivers ive read good things about them just unsure how to tie them into the system. If I have two amps running off two seperate pre amp out puts does that mean I need two line drivers one for each amp. Or is it better to find a eq with a line driver built in. Also can you send to much voltage to the amps by using a line driver? I hear of people using line drivers to up the signal of the ipod, is this done by running the ipod into the line driver into the aux inputs of the head unit? Is an eq with built in line driver and aux inputs for the ipod the best way to go wouldnt that take care of all of it? Sorry so many questions any help would be appreciated or any links that might help me out. Thanks

Justin, I have three line drivers on my system. I am running a Zapco amp to the tower Defcon's, another Zapco running the 4 MB's in the boat, and a 12" Eclipse sub. Also have an Ipod connection, XM, etc. The line drivers are the BEST part of my system. Once I have the stereo on, I adjust the volume on the Sony remote to about 30, and never touch the stereo the rest of the day. I have one line driver for the sub, one for the MB's in the boat, and one for the tower. It is so easy to adjust what speakers I want on. I never have to get into the stereo and adjust sub level, fader, etc. If I want more sub, I just turn a knob, if I drop a skier, I cut down the tower while I am turning around so I don't piss off the whole lake. If we are pulling a rider, and we want to talk in the boat, I turn down the boat speakers, and leave the tower going for the rider. Realy slick set-up. My stereo guys hooked up everything, and I am no audio whiz, I just listen to the tunes, but, as far as I can explain, the outputs from the stereo going to the amps, run through the line drivers first. The Ipod is connected directly to a hot wire, and to the aux inputs in the rear of the Sony head unit. I put the Ipod in the cradle, plug in one plug into the Ipod, and it is done, and not running off the Ipod battery, and do not have to adjust the volume on the Ipod. Very clean and easy set-up, especially for techno-challenged people like me. Hope this helps! <img src="http://www.wakeworld.com/MB/Discus/messages/65921/224899.jpg" alt="">

Hey Buzz :I dont think thoes are line driver's Do a search on line drivers.

Grant, Like I said in my post, I am no audio whiz, and may have my terminology wrong (probably not a good thing when I am trying to explain something). Thanks for jumping in and clarifying. I can always learn too. What I have in the pic are "Peripheral" "PCS1" rca level controls. Maybe these are refered to as "volume controls" and not line drivers. Probably my mistake. Are line drivers more of an equalizer-looking thing, with several volume controls? You got me. Anyway, hope you cal clarify (I am sure you can) so that Justin gets the right info. I was just trying to give him an idea what I have since I thought it was the same or similaras what he was asking about. Like I said, I just crank the tunes, I don't build or design the stuff. That's for the guru's like you!! Smokin work BTW! Take care! Buzz (BTW - I did not ride the short bus, but maybe should have!) jk

look at the audiocontrol gear..they have a speciific line driver for kicking up the voltage to 9v. you can also do the external crossover form them and it will kick up the voltage to 9v.. i really like the 24xs.. it has a phase control for sub intergation... check with a audiocotrol dealer- you should be able to use y adapters with it... i would try that between the head unit and amp before you add one to the ipod..

Im using the Audio Control unit and I like it <img src="http://www.wakeworld.com/MB/Discus/messages/65921/224930.jpg" alt="">

Buzz, No problem It didnt look like line driver adjustments, but who knos you could have had coustom ones made, I didnt know, The PAC line adjuster's work great for exactley what you described them for.

With multiple amps and the weak XMD3 head unit I decided that the signal would need a boost and some additional control. I wanted a non fading sub output and a aux input on the line driver/EQ/XO unit. One of the audiocontrol units offered the aux input a different unit offered the sub out but they didn't have a unit that offered both so I looked around and found a cheap Clarion unit and a cheap Soundstream unit. I bought the Soundstream unit and I have been happy with it's performance. It definately helps to have the control of the output levels. Now I use the deck's aux in for my XM radio and the EQ's aux in for the MP3 player. I feel the minimal investment really helps the system. It's really surprising that more people don't use these inexpensive devices to take control of the systems in their boats. <img src="http://www.wakeworld.com/MB/Discus/messages/65921/224944.jpg" alt="">

mike, that is a great unit(sounstream) and a slick install... you have me thinking now...

Thanks for the input guys

Mike I feel your pain on the Audio Control stuff i ran into the exact same problem the 4.1 has things the 3.1 dosent ect. Harrold just picked up a PPI unit that he realy like's

is there a line driver without the eq ?}

I've been looking at this one.. Audio Control Matrix <a href="http://www.mobileaudiocontrol.com/product.asp?Product_id=14164" target="_blank">http://www.mobileaudiocontrol.com/product.asp?Product_id=14164</a>

cj.... i have never seen that model.. WOW !!!! that beats out the regular line driver hands down.. have you deen a dash mounted preamp without the eq ? it would be cool to do the volume,fade, and have a extra input..

I have the audiocontrol matrix. You can find them new for about $200. I got a used via ebay for 120. I am running three sets of 2 V RCA's to it: front/rear/sub. It is installed close to the head unit, and then long rca's run to my amps. My amp specs say they can handle 8V, but I am using about 6 leaving from the matrix, according to the led lights on the matrix. Since I have three outputs from my head unit, I can use the fader controls to control the tower speakers. I've thought about using just one of outputs on my head unit and adding in an eq/with aux inputs. I would then use the eq to fade the tower and subs. I looked for a six-channel input line-driver with aux-inputm but could not find one. That would have been perfect.

If you mean a multichannel dash mounted line driver, I'm almost to the point of building one. I don't think there is one on the market. I think that us boat guys want features that the car guys don't need. I've been thinking about taking the Matrix and building a face panel with remote mounted pots for each control that I want. It could have jacks for ins and outs too. It would void the hell out of the warrantee, oh well. I'd start from scratch but the higher end heads have outputs over 2.9vdc which would require a +/- 15 vdc switching supply, a pain to design and make quiet and small. That's why I'm thinking of bastardizing a Matrix.

what do think about using it with pac lc-1's to a faceplate ( like buzz's) and connect it with rca's ? if i remember, i think zapco built a pre-amp only unit.. (early 90's)... i wil check around, i really like this idea a lot..

That will work, but you will lose some fidelity, i.e. volume and highs because it is a passive device. It is probably a 10k-25K dual ganged pot in a little box. At FULL volume, there is basically a 10k or 25k resistor grounding the preamp output of your head. Whatever is left goes to the amp. The resistor is always in there. As you turn down the volume, highs shunt to ground more than lows. This can be helped by bypassing the pot with a small capacitor. I bought a David Navone level control, it wasn't bypassed and the pot was linear taper, not audio taper. That means that at half turn, the volume is not at half, and it changes drastically as you turn it past a certain position. The parts used in that device were super low quality, I trashed it. I paid a lot for my head unit, amps and RCA interconnects. I don't want to compromise the entire system with a volume control that I know for a fact will have a detrimental effect on the sound. Nothing against the PAC LC-1, it does what it says it will do and is an inexpensive, easy fix for a complex problem. You can make one yourself for a few bucks. Probably not worth it as LC-1's are only 12$ The problem is that it compromises the high input impedance of your expensive amp by essentially shorting the input with a resistor. On the other end of the cable, most head unit RCA's have about a 40k output impedance, a 10k pot loads them too much. If you use a high value pot, like say 250k, you get into noise problems because it acts like a radio antenna. In boats, we do things that car guys don't. We have long RCA cable runs that filter highs because of their inherent capacitance. We also run multiple amps at very different volumes that we need to change all the time while out on the lake. We need sturdy construction, shielding, and corrosion protection for a boat. I think we need something that doesn't yet exist. What I want to try to build is a 6 channel high fidelity buffer/preamp/line driver with faceplate controls. It would have to be able to handle large input signals without distortion (500k input impedance), and be able to drive long cable runs with an output impedance of 100 ohms or so with enough gain to put out a 9V output if you need it. That means that you won't lose highs or volume through long RCA cable runs. If your head unit had a standard line level output (.1 to 1.5vac)you could boost it and get less cable loss and less noise from your amp. It would have to have a pot for each pair of channels, and simple indicators that are visible in daylight. Maybe a mute button for each channel. The circuit board should be conformal coated so that it does not corrode. I'd use top quality parts like Bourns pots instead of third world junk. You can do the same thing with the fader controls on the head unit, but it sure can be a pain to get to them while you are slowing down and trying to not run over the rider, the rope, not spill your beer, etc. I know it is not going to be worth it for most people, but I get worked up about little things sometimes, hence my screen name<IMG SRC="http://www.wakeworld.com/MB/Discus/clipart/happy.gif" ALT=":-)" BORDER=0> I doubt I could build one better than the Matrix, so I'm thinking about modding one to do what I want.

cj- know what you mean about passive lc-1.. there is a frequency rolloff that worsens with increased cable length... here are a couple suggestions that might work.. 1- here a remote volume for the audiocontrol line driver <a href="http://www.mobileaudiocontrol.com/product.asp?Product_Id=28476&d_Id=8138&l1= 8138&l2=" target="_blank">http://www.mobileaudiocontrol.com/product.asp?Product_Id=28476&d_Id=8138&l1= 8138&l2=</a> 2. i think you could use the the pac lc-1 and the audiocontrol driver IF.... drumroll please !!!! the pac 1 was used right out the back of the audiocontrol line driver (plug it in with male rca or very short lengths) or use a audiocontrol 4i and redo the faceplate.. i agree with you, it is hard to beat the audiocontrol matrix..its would be hard to come up with a in dash face